CYCLOHEXANE

SYNONYMS:Cyclohexane; CYCLOHEXANE; Hexamethylene; Hexanaphthene; Hexahydrobenzene; 110-82-7; Cyclohexan; Cykloheksan; Cicloesano; Cyclohexaan;Benzene, hexahydro-; Polycyclohexane; Benzenehexahydride; hexahydro-Benzene; Poly(cyclohexane); Cyclohexaan; Cyclohexan; Cicloesano; Cykloheksan; ; Cyclohexane, oxidized,non-volatile residue; Ciclohexano; Zyklohexan; cyclo-hexane; Cyclohexane,oxidized; Cyclohexane, homopolymer; siklohegzan; siklohekzan; siklohegsan; sikloheksan; siklo hegzan; siklo hekzan; siklo hegsan; siglo heksan;CYCLOHEXANE

Cyclohexane is an alicyclic hydrocarbon comprising a ring of six carbon atoms; the cyclic form of hexane, used as a raw material in the manufacture of nylon.

It has a role as a non-polar solvent. It is a cycloalkane and a volatile organic compound. Cyclohexane appears as a clear colorless liquid with a petroleum-like odor. Used to make nylon, as a solvent, paint remover, and to make other chemicals. Flash point -4°F. Density 6.5 lb / gal (less than water) and insoluble in water. Vapors heavier than air.

Cyclohexane is a cycloalkane with the molecular formula C6H12. Cyclohexane is non-polar. Cyclohexane is a colourless, flammable liquid with a distinctive detergent-like odor, reminiscent of cleaning products (in which it is sometimes used). Cyclohexane is mainly used for the industrial production of adipic acid and caprolactam, which are precursors to nylon.[5]

Cyclohexyl is the alkyl substituent of cyclohexane and is abbreviated Cy

Preferred IUPAC name: Cyclohexane

Other names: Hexanaphthene (archaic

CAS Number: 110-82-7

What is Cyclohexane?

Cyclohexane (also known as CYX, hexamethylene, hexahydrobenzene, hexanaphthene, and benzenehexahydride) is a colourless, volatile, and flammable liquid with the formula C6H12.

It has a mild odour and is insoluble in water but soluble in alcohol, ether, acetone, benzene, and ligroin.

Cyclohexane occurs naturally in petroleum crude oil, volcanic gases and cigarette smoke.

How is it produced?

Industrial cyclohexane can be produced by two methods. The first is the catalytic hydrogenation of benzene using rhodium on carbon, and the second method is via fractional distillation of petroleum.

How is it stored and distributed?

Cyclohexane has a specific gravity of 0.78 and a flashpoint of -20° C and is highly flammable. It should be stored in a cool, dry, and well-ventilated area which is free from the risk of ignition. For transportation purposes, it is classified as hazard class 3 and packing group II and is should be labelled as an irritant, and harmful if swallowed or inhaled.

What Cyclohexane used for?

The remaining 10% is used both as a solvent for paints, resins, varnish and oil, and as a plasticiser.

Cyclohexane can also be used as an intermediate in the manufacture of other industrial chemicals such as cyclohexanone and nitrocyclohexanone.

Cyclohexane [ACD/Index Name] [ACD/IUPAC Name] [Wiki]

110-82-7 [RN]

1900225 [Beilstein]

203-806-2 [EINECS]

Cicloesano [Italian]

cyclohexaan [Dutch]

Cyclohexan [German] [ACD/IUPAC Name]

Cyclohexane [French] [ACD/Index Name] [ACD/IUPAC Name]

Cykloheksan [Polish]

MFCD00003814 [MDL number]

12217-02-6 [RN]

203-806-2MFCD00003814

Acid red 300

Benzene hexahydride

Benzene, hexahydro-

benzenehexahydride

Cyclohexane 100 Âµg/mL in Methanol

Cyclohexane 2000 Ã‚Âµg/mL in Methanol

Cyclohexane 2000 Âµg/mL in Methanol

Cyclohexane GC, for residue analysis

Cyclohexane, 99%

Cyclohexane, ACS Grade

Cyclohexane, GlenDry, anhydrous

Cyclohexane, GlenPure, analytical grade

hexahydrobenzene

http://www.hmdb.ca/metabolites/HMDB0029597

https://www.ebi.ac.uk/chebi/searchId.do?chebiId=CHEBI:29005

InChI=1S/C6H12/c1-2-4-6-5-3-1/h1-6H2

L6TJ [WLN]

Zyklohexan [German]

环己烷 [Chinese]

CYCLOHEXANE

110-82-7

Hexamethylene

Hexanaphthene

Hexahydrobenzene

Cyclohexan

Cykloheksan

Cicloesano

Cyclohexaan

Benzene, hexahydro-

Benzenehexahydride

Polycyclohexane

hexahydro-Benzene

Poly(cyclohexane)

RCRA waste number U056

Cyclohexaan [Dutch]

Cyclohexan [German]

Cicloesano [Italian]

Cykloheksan [Polish]

Caswell No. 269

cyclo-hexane

UNII-48K5MKG32S

HSDB 60

NSC 406835

CCRIS 3928

Cyclohexane, oxidized, non-volatile residue

EINECS 203-806-2

cyclohexane density

cyclohexane vs benzene

cyclohexane structure

cyclohexane uses

cyclohexane structural formula

cyclohexane boiling point

cyclohexane polar or nonpolar

cyclohexane sds

ciclo-hexano (pt)

cicloesano (it)

ciclohexan (mt)

Ciclohexan (ro)

ciclohexano (es)

cikloheksan (hr)

cikloheksan (sl)

cikloheksanas (lt)

cikloheksāns (lv)

ciklohexán (hu)

cyclohexaan (nl)

cyclohexan (da)

Cyclohexan (de)

cyclohexane (fr)

cykloheksan (no)

cykloheksan (pl)

cyklohexan (cs)

cyklohexan (sv)

cyklohexán (sk)

Sykloheksaani (fi)

Tsükloheksaan (et)

κυκλοεξάνιο (el)

циклохексан (bg)

CAS names

Cyclohexane

IUPAC names

cyclehexane

cyclohaxane

Cyclohexan

CYCLOHEXANE

Cyclohexane

cyclohexane

Cyclohexane

cyclohexane

cyklohexan

Hexahydrobenzene, Hexamethylene, Naphthene

110-82-7; Hexamethylene; Hexanaphthene;

Hexahydrobenzene; Cyclohexan; Cykloheksan; Cicloesano; Cyclohexaan;Benzene, hexahydro-; Benzenehexahydride; Polycyclohexane; hexahydro-Benzene; Poly(cyclohexane); SKLOHEKZAN; SKLOHEGZAN; siklohexan; SiklohegzanRCRA waste number U056; Cyclohexaan[Dutch]; Cyclohexan [German]; Cicloesano [Italian]; Cykloheksan [Polish]; Caswell No. 269; UNII-48K5MKG32S; HSDB 60; NSC 406835; CCRIS 3928; EINECS 203-806-2; UN1145; RCRA waste no. U056; EPA PesticideChemical Code 025901 ; AI3-08222; Cyclohexane, oxidized, non-volatile residue; 48K5MKG32S; CHEBI:29005; XDTMQSROBMDMFD-UHFFFAOYSA-N; MFCD00003814; Cyclohexane, ACS reagent; Cyclohexane, 99+%, pure; Ciclohexano; Cyclohexane, 99.5%, extra pure; Cyclohexane, 99.8%, for HPLC; Cyclohexane, 99.5%, for analysis; Cyclohexane, ACS reagent, >=99%; Cyclohexane, 99+%, for spectroscopy; Cyclohexane, for HPLC, >=99.7%; Cyclohexane, 99+%, for spectroscopy ACS; Cyclohexane, for pesticide residue analysis; Cyclohexane, 99.5%, Extra Dry, AcroSeal(R); cylcohexane cylohexane; Cyclohexane, puriss. p.a., CYCLOHEXANE; CYCLOHEXANE; HEXAMETHYLENE; HEXANAPHTHENE; HEXAHYDROBENZENE; 110-82-7; CYCLOHEXAN;CYKLOHEKSAN; CCLOESANO; CYCLOHEXAAN;BENZENE, HEXAHYDRO-;POLYCYCLOHEXANE; BENZENEHEXAHYDRDE; HEXAHYDRO-BENZENE; POLY(CYCLOHEXANE); CYCLOHEXAAN; CYCLOHEXAN; CCLOESANO; CYKLOHEKSAN; ; CYCLOHEXANE, OXDZED,NON-VOLATLE RESDUE; CCLOHEXANO; ZYKLOHEXAN; CYCLO-HEXANE;CYCLOHEXANE,OXDZED; CYCLOHEXANE, HOMOPOLYMER; SKLOHEGZAN; SKLOHEKZAN; SKLOHEGSAN; SKLOHEKSAN;ACS reagent, >=99.5% (GC); Zyklohexan; cyclo-hexane; Cyclohexane, 99.5%, Extra Dry over Molecular Sieve, AcroSeal(R); EINECS 270-147-5Cyclohexane HPLC grade; Cyclohexane, for HPLC; Cyclohexane, homopolymer; Cyclohexane, ACS Grade; ACMC-1BUC3; CYCLOHEXANE- D12; DSSTox_CID_1923; bmse000545; Cyclohexane, 99% 1L; WLN: L6TJ; EC 203-806-2; EC 270-147-5; AC1L1Q7Q; DSSTox_RID_76404; DSSTox_GSID_21923; ghl.PD_Mitscher_leg0.242; Cyclohexane, LR, >=99%; KSC176E2J; CHEMBL15980; Cyclohexane, JIS special grade; Cyclohexane, analytical standard; Cyclohexane, p.a., 99.0%; DTXSID4021923; CTK0H6224; Cyclohexane, anhydrous, 99.5%; Cyclohexane, AR, >=99.5%; KS-00000WCC; MolPort-001-785-799; Cyclohexane, reaction product with oxygen, nonvolatile residue; BCP08072; ZINC1532203; Tox21_201087; ANW-56408; LS-516;NSC406835; STL283116; Cyclohexane, >=99.5%, PRA grade; Cyclohexane, for HPLC, >=99.9%; AKOS000119975; Cyclohexane, HPLC grade, >=99.9%; ZINC100503963; CYCLOHEXANE, HPLC/SPECTRO GRADE, MCULE3136361765, NSC-406835; UN 1145; Cyclohexane 2000 microg/mL in Methanol; NCGC00248918-01; NCGC00258639-01; 25012-93-5; 68411-76-7; AN-22625; CAS-110-82-7; CJ-24168; Cyclohexane, puriss., >=99.5% (GC)KB-76252; Cyclohexane [UN1145] [Flammable liquid]; Cyclohexane, SAJ first grade, >=99.0%; Cyclohexane, Laboratory Reagent, >=99.8%; Cyclohexane, p.a., ACS reagent, 99.0%, TR-002195; TX-017501;Cyclohexane [UN1145] [Flammable liquid];Cyclohexane, UV HPLC spectroscopic, 99.5%; Cyclohexane [ACD/Index Name] [ACD/IUPAC Name] [Wiki];110-82-7 [RN]; 1900225 [Beilstein]; 203-806-2 [EINECS]; Cicloesano [Italian]; cyclohexaan [Dutch]; Cyclohexan [German] [ACD/IUPAC Name]; Cyclohexane [French[ACD/Index Name] [ACD/IUPAC Name]; Cykloheksan [Polish]; MFCD00003814 [MDL number];CYCLO; HEXANE; HEXAN; HEKSAN; SKLO; SKLO HEGZAN; SKLO HEKZAN; SKLO HEGZAN ; SIKLO; SIKLO HEKZAN; SIKLO HEGZAN; SKLOHEGZAN;SIKLOHEKZAN; SIKLOHEGZAN; SKLOHEGZEN; SKLO HEGZEN; SIKLO HEGZEN; SIKLOHEGZEN; CYCLOHEXAN; CYCLOHEKSAN; CLYCLO HEKSAN; CYCLOXANE; CYCLO HEKSAN; CYCLOHEKZEN; CYCLO; HEKSEN;HEKSN ; HEGZN; CCYLO; SKLO; SIKLOHEGZN; SIKLOHEGZN; SKLO HEGZN;UN 1145; Benzene hexahydride; Benzene, hexahydro-; benzenehexahydride; hexahydrobenzene; L6TJ [WLN]; Zyklohexan; Hexahydrobenzen; Hexamethylene; Naphthene; cyclo; hexane; hexan; heksan; siklo; siklo hegzan; siklo hekzan; siklo hegzan ; sklo; sklo hekzan; sklo hegzan; siklohegzan; sklohekzan; sklohegzan; siklohegzen; siklo hegzen; sklo hegzen; sklohegzen; cyclohexan;cycloheksan; clyclo heksan; cycloxane; cyclo heksan; cyclohekzen; cyclo; heksen; heksin ; hegzin; cicylo; siklo; sklohegzin; sklohegizin; siklo hegzin; sklo ; hekzin;hegizin; cyclohexane; ; Cyclohexane, analytical standard; Cyclohexane, p.a., 99.0%; DTXSID4021923; CTK0H6224; Cyclohexane, anhydrous, 99.5%; Cyclohexane, AR,>=99.5%; KS-00000WCC; MolPort-001-785-799; Cyclohexane, reaction product with oxygen, nonvolatile residue; BCP08072; ZINC1532203; Tox21_201087; ANW-56408; LS-516;NSC406835; STL283116; Cyclohexane, >=99.5%, PRA grade; Cyclohexane, for HPLC, >=99.9%; AKOS000119975; Cyclohexane, HPLC grade, >=99.9%; ZINC100503963; CYCLOHEXANE, HPLC/SPECTRO GRADE, MCULE-3136361765, NSC-406835; UN 1145; Cyclohexane 2000 microg/mL in Methanol; NCGC00248918-01; NCGC00258639-01; 25012-93-5; 68411-76-7; AN-22625; CAS-110-82-7; CJ-24168; Cyclohexane, puriss., >=99.5% (GC)KB-76252; Cyclohexane [UN1145] [Flammable liquid]; Cyclohexane, SAJ first grade, >=99.0%; Cyclohexane, Laboratory Reagent, >=99.8%; Cyclohexane, p.a., ACS reagent, 99.0%, TR-002195; TX-017501;Cyclohexane [UN1145] [Flammable liquid];Cyclohexane, UV HPLC spectroscopic, 99.5%; Cyclohexane [ACD/Index Name] [ACD/IUPAC Name] [Wiki];110-82-7 [RN]; 1900225 [Beilstein]; 203-806-2 [EINECS]; Cicloesano [Italian]; cyclohexaan [Dutch]; Cyclohexan [German] [ACD/IUPAC Name]; Cyclohexane [French] [ACD/Index Name] [ACD/IUPAC Name]; Cykloheksan [Polish]; MFCD00003814 [MDL number];CYCLO; HEXANE; HEXAN; HEKSAN; SKLO; SKLO HEGZAN; SKLO HEKZAN; SKLO HEGZAN ; SIKLO; SIKLO HEKZAN; SIKLO HEGZAN; SKLOHEGZAN;SIKLOHEKZAN; SIKLOHEGZAN; SKLOHEGZEN; SKLO HEGZEN; SIKLO HEGZEN; SIKLOHEGZEN; CYCLOHEXAN; CYCLOHEKSAN; CLYCLO HEKSAN; CYCLOXANE; CYCLO HEKSAN; CYCLOHEKZEN; CYCLO; HEKSEN; HEKSN ; HEGZN; CCYLO; SKLO; SIKLOHEGZN; SIKLOHEGZN; SKLO HEGZN;UN 1145; Benzene hexahydride; Benzene, hexahydro-; benzenehexahydride; hexahydrobenzene; L6TJ [WLN]; Zyklohexan; Hexahydrobenzen; Hexamethylene; Naphthene; cyclo; hexane; hexan; heksan; siklo; siklo hegzan;siklo hekzan; siklo hegzan ; sklo; sklo hekzan; sklo hegzan; siklohegzan; sklohekzan; sklohegzan; siklohegzen; siklo hegzen; sklo hegzen; sklohegzen; cyclohexan;cycloheksan; clyclo heksan; cycloxane; cyclo heksan; cyclohekzen; cyclo; heksen; heksin ; hegzin; cicylo; siklo; sklohegzin; sklohegizin; siklo hegzin; sklo ; hekzin;hegizin; cyclohexane; siklohegzan; siklo hegzan; cyclo hexan; cyclo hexane

Cyclohexane is an alicyclic hydrocarbon comprising a ring of six carbon atoms; the cyclic form of hexane, used as a raw material in the manufacture of nylon. It has a role as a non-polar solvent. It is a cycloalkane and a volatile organic compound.Cyclohexane appears as a clear colorless liquid with a petroleum-like odor. Used to make nylon, as a solvent, paint remover, and to make other chemicals. Flash point -4°F. Density 6.5 lb / gal (less than water) and insoluble in water. Vapors heavier than air.Cyclohexane is a colorless liquid. It has a pungent, petroleum-like odor. It is slightly soluble in water. USE: Over 98% of the cyclohexane produced is used to make nylon intermediates. It is used as a solvent for lacquers, resins and synthetic rubber. It can also be used as paint and varnish remover. It is present in all crude oils. It can be released in volcanic emissions, tobacco smoke and plant volatiles. EXPOSURE: People that work in industries where products containing cyclohexane are used will have the highest exposure. Nylon industry workers are the most likely to be exposed. Other industries could include shoe and leather factories, printing plants, and furniture and mechanical industries. The general population may be exposed to cyclohexane from tobacco smoke, gasoline fumes or smog. Cyclohexane can be found at low levels in surface, ground and drinking waters. It can also be found in air. It breaks down in air by reaction with other chemicals. It is expected to rapidly evaporate from soil and water surfaces. Cyclohexane that remains in soil or water may be slowly broken down by microorganisms. It is expected to build up in aquatic organisms. RISK: Cyclohexane can depress the central nervous system in humans. This can cause headache, dizziness, narcosis, and death at high levels of exposure. Dry throat and eye irritation have been reported by people breathing air concentrations of 250 ppm for 4 hours. In laboratory animals, central nervous system depression has been observed in rats and mice breathing high air concentrations. No birth defects or abortions were found in pregnant rats breathing very high air concentrations. No effects on the ability to produce offspring were found in two generations of rats breathing very high air concentrations. The potential for cyclohexane to cause cancer in humans has not been assessed by the International Agency for Research on Cancer or in the U.S. National Toxicology Program Twelfth Report on Carcinogens. The U.S. EPA IRIS Program determined that data are inadequate for an assessment of human carcinogenic potential of cyclohexane. The IRIS document noted that no human data and no adequate studies of cancer in laboratory animals were located. Benzene can be hydrogenated catalytically to cyclohexane in either the liquid or the vapor phase in the presence of hydrogen. Several cyclohexane processes, which use nickel, platinum, or palladium as the catalyst, have been developed. Usually, the catalyst is supported, e.g., on alumina, but at least one commercial process utilizes Raney nickel.Campbell ML; Cyclohexane. Ullmann’s Encyclopedia of Industrial Chemistry 7th ed. (1999-2014). NY, NY: John Wiley & Sons. Online Posting Date: October 15, 2011.from HSDB.Occurs in petroleum (0.5-1.0%). Obtained in the distillation of petroleum … In distillation of petroleum the C4-400 °F boiling range naphthas are fractionated to obtain C5-200 °F naphtha containing 10-14% cyclohexane which on superfractionation yields an 85% concentrate (which is sold as such); further purification /of 85% concentrate cyclohexane/ necessitates isomerization of pentanes to cyclohexane, heat cracking for removing open chain hydrocarbons and sulfuric acid treatment to remove aromatic compounds.Cyclohexane is a cycloalkane with the molecular formula C6H12. Cyclohexane is a colourless, flammable liquid with a distinctive detergent-like odor, reminiscent of cleaning products (in which it is sometimes used). Cyclohexane is mainly used for the industrial production of adipic acid and caprolactam,Although rather unreactive, cyclohexane undergoes catalytic oxidation to produce cyclohexanone and cyclohexanol. The cyclohexanone-cyclohexanol mixture, called “KA oil”, is a raw material for adipic acid and caprolactam, precursors to nylon. Several million kilograms of cyclohexanone and cyclohexanol are produced annually.[9]

Laboratory solvent and other niche uses.It is used as a solvent in some brands of correction fluid. Cyclohexane is sometimes used as a non-polar organic solvent, although n-hexane is more widely used for this purpose. It is frequently used as a recrystallization solvent, as many organic compounds exhibit good solubility in hot cyclohexane and poor solubility at low temperatures.

Cyclohexane is also used for calibration of differential scanning calorimetry (DSC) instruments, because of a convenient crystal-crystal transition at -87.1 °C.[14]

Cyclohexane vapour is used in vacuum carburizing furnaces, in heat treating equipment manufacture. which are precursors to nylon.On an industrial scale, cyclohexane is produced by hydrogenation of benzene in the presence of a Raney nickel catalyst.[7] Producers of cyclohexane account for approximately 11.4% of global demand for benzene.[8] The reaction is highly exothermic, with ΔH(500 K) = -216.37 kJ/mol). Dehydrogenation commenced noticeably above 300 °C, reflecting the favorable entropy for dehydrogenation.[9]Catalytic hydrogenation of benzene to cyclohexane with a raney-nickel catalyst.The 6-vertex edge ring does not conform to the shape of a perfect hexagon. The conformation of a flat 2D planar hexagon has considerable angle strain because its bonds are not 109.5 degrees; the torsional strain would also be considerable because all of the bonds would be eclipsed bonds. Therefore, to reduce torsional strain, cyclohexane adopts a three-dimensional structure known as the chair conformation, which rapidly interconvert at room temperature via a process known as a chair flip. During the chair flip, there are three other intermediate conformations that are encountered: the half-chair, which is the most unstable conformation, the more stable boat conformation, and the twist-boat, which is more stable than the boat but still much less stable than the chair. The chair and twist-boat are energy minima and are therefore conformers, while the half-chair and the boat are transition states and represent energy maxima. The idea that the chair conformation is the most stable structure for cyclohexane was first proposed as early as 1890 by Hermann Sachse, but only gained widespread acceptance much later. The new conformation puts the carbons at an angle of 109.5°. Half of the hydrogens are in the plane of the ring (equatorial) while the other half are perpendicular to the plane (axial). This conformation allows for the most stable structure of cyclohexane. Another conformation of cyclohexane exists, known as boat conformation, but it interconverts to the slightly more stable chair formation. If cyclohexane is mono-substituted with a large substituent, then the substituent will most likely be found attached in an equatorial position, as this is the slightly more stable conformation.

Cyclohexane has the lowest angle and torsional strain of all the cycloalkanes; as a result cyclohexane has been deemed a 0 in total ring strain.. Solid phases

Cyclohexane has two crystalline phases. The high-temperature phase I, stable between 186 K and the melting point 280 K, is a plastic crystal, which means the molecules retain some rotational degree of freedom. The low-temperature (below 186 K) phase II is ordered. Two other low-temperature (metastable) phases III and IV have been obtained by application of moderate pressures above 30 MPa, where phase IV appears exclusively in deuterated cyclohexane (application of pressure increases the values of all transition temperatures.The cyclohexane oxidation plant shown in Fig. 2.55 consisted of a train of six reactors in series in which cyclohexane was oxidized to cyclohexanone and cyclohexanol by air injection in the presence of a catalyst. The reactions are exothermic. The feed to the reactors was a mixture of fresh cyclohexane and recycled material. The product from the reactors still contained approximately 94% of cyclohexane. The liquid reactants flowed from one reactor to the next by gravity. In subsequent stages, the reaction product was distilled to separate the unreacted cyclohexane, which was recycled to the reactors, and the cyclohexanone and cyclohexanol, which were converted to caprolactam. The operating conditions in the reactor according to the design were 8.8 bar (g) and 155°C.The cyclo-hexane oxidation plant shown in Figure 2-55 consisted of a train of six reactors in series in which cyclo-hexane was oxidized to cyclo-hexanone and cyclo-hexanol by air injection in the presence of a catalyst. The reactions are exothermic. The feed to the reactors was a mixture of fresh cyclo-hexane and recycled material. The product from the reactors still contained approximately 94 percent of cyclo-hexane. The liquid reactants flowed from one reactor to the next by gravity. In subsequent stages, the reaction product was distilled to separate the unreacted cyclo-hexane, which was recycled to the reactors, and the cyclo-hexanone and cyclo-hexanol, which were converted to caprolactam. The operating conditions in the reactors according to the design were 8.8 bar(g) and 155°C.The cyclohexane/benzene/hydrogen system involves the reversible reaction at atmospheric pressure in the temperature range of 478-589K. Both endothermic dehydrogenation and exothermic hydrogenation reactions are catalytic reactions. The enthalpy of the reaction is very large. Moreover, the technology for the hydrogenation of benzene has already been formed on the industrial scale [47], which will promote the potential application of the cyclohexane/benzene/hydrogen system for chemical reaction heat storage. Therefore, this reversible reaction is considered as a promising candidate for chemical reaction heat storage. The existence of impurities in reagents may incur a side reaction. It is important to pretreat the reagents to eliminate impurities. Cacciola et al. [48] investigated the interrelationship between the COP and various influential factors for the cyclohexane/benzene/hydrogen system. For a dehydrogenation temperature of 473K and hydrogenation temperature of 573K, both thermal energy storage density and the COP reached the highest value when reaction conversions of the dehydrogenation and hydrogenation reactions were 30% and 70%, respectively.The feed contains cyclohexane, benzene, toluene and o-xylene. Water and acetone are added as extraction solvents. In the first and second column (C1 and C2) the high boiling components (o-xylene (3) and toluene (6)) are removed as bottom products. Subsequently, benzene (9) and cyclohexane (12) are captured as distillate fraction. Benzene and cyclohexane are forming an azeotrope and have close boiling points. Benzene is separated from cyclohexane in C3 by adding acetone (7) which forms an azeotrope with cyclohexane at around 70 wt.-% acetone. Finally, cyclohexane is removed from acetone in an extraction stage (E1) by adding water (14) as a solvent. Stream 11 contains water, acetone and traces of cyclohexane and is separated at column C5. The solvents acetone (13) and water (14) are recycled.

Sikloheksan, alt karbon atomlu bir halka içeren bir alisiklik hidrokarbondur; naylon üretiminde bir hammadde olarak kullanlan, hekzan siklik formu. Polar olmayan bir çözücü olarak bir rolü vardr. Bir sikloalkan ve uçucu bir organik bileiktir. Sikloheksan, petrol benzeri bir kokusu olan berrak, renksiz bir sv halinde görünür. Naylon, çözücü olarak, boya sökücü ve dier kimyasallar yapmak için kullanlr. Parlama noktas -4 ° F. Younluk 6,5 lb / gal (sudan az) ve suda çözünmez. Havadan ar buharlar. Sikloheksan renksiz bir svdr. Keskin, petrol benzeri bir kokuya sahiptir. Suda az çözünür. KULLANIM: Üretilen sikloheksann% 98’inden fazlas naylon ara ürünler yapmak için kullanlr. Lak, reçineler ve sentetik kauçuk için çözücü olarak kullanlr. Boya ve vernik sökücü olarak da kullanlabilir. Tüm ham yalarda bulunur. Volkanik emisyonlarda, tütün dumannda ve bitki uçucu maddelerinde serbest braklabilir. MARUZ KALMA: Sikloheksan içeren ürünlerin kullanld endüstrilerde çalan insanlar en yüksek düzeyde maruz kalacaklardr. Naylon endüstrisi çalanlarnn maruz kalmas en muhtemel olandr. Dier endüstriler arasnda ayakkab ve deri fabrikalar, matbaa tesisleri ve mobilya ve mekanik endüstrileri yer alabilir. Genel popülasyon sikloheksana tütün duman, benzin duman veya smogdan maruz kalabilir. Sikloheksan, yüzey, yer alt ve içme sularnda düük seviyelerde bulunabilir. Havada da bulunabilir. Dier kimyasallarla reaksiyona girerek havay bozar. Toprak ve su yüzeylerinden hzla buharlamas beklenir. Toprakta veya suda kalan sikloheksan, mikroorganizmalar tarafndan yavaça bozulabilir. Su organizmalarnda birikmesi bekleniyor. RSK: Sikloheksan insanlarda merkezi sinir sistemini durdurabilir. Bu, yüksek maruziyet seviyelerinde ba ars, ba dönmesi, narkoz ve ölüme neden olabilir. Kuru boaz ve göz tahrii, 4 saat boyunca 250 ppm’lik hava konsantrasyonlarn solan insanlar tarafndan bildirilmitir. Laboratuar hayvanlarnda, farelerde ve yüksek hava konsantrasyonlar soluyan farelerde merkezi sinir sistemi çökmesi gözlenmitir. Çok yüksek hava konsantrasyonlar soluyan gebe sçanlarda doum kusurlar veya düükler bulunmad. Çok yüksek hava konsantrasyonlar soluyan iki kuak sçanda yavru üretme kabiliyeti üzerinde bir etki bulunmad. Sikloheksann insanlarda kansere neden olma potansiyeli, Uluslararas Kanser Aratrma Ajans veya ABD Ulusal Toksikoloji Program Onikinci Raporunda Kanserojenler Raporu’nda deerlendirilmemitir. ABD EPA IRIS Program, sikloheksann insan kanserojen potansiyelinin deerlendirilmesi için verilerin yetersiz olduunu belirledi. IRIS belgesinde, hiçbir insan verisinin olmad ve laboratuar hayvanlarnda yeterli kanser çalmasnn bulunmad belirtildi. Benzen, hidrojenin varlnda sv veya buhar fazndaki sikloheksana katalitik olarak hidrojenlenebilir. Katalizör olarak nikel, platin veya paladyum kullanan birkaç sikloheksan ilemi gelitirilmitir. Genellikle, katalizör, örnein alümina üzerinde desteklenir, ancak en az bir ticari ilem Raney nikel kullanr. Sikloheksan. Ullmann Endüstri Kimyas Ansiklopedisi 7. basm. (1999-2014). NY, NY: John Wiley ve Oullar. Online Gönderme Tarihi: 15 Ekim 2011, HSDB’den. Petrol petrol fiyatlar (% 0,5-1,0). Petrolün damtlmasnda elde edilir … Petrolün damtlmasnda c4-400 ° F kaynama aral naftalar fraksiyonlanr,% 10-14 sikloheksan içeren C5-200 ° F nafta elde edilir ve süperfraksiyon ileminde% 85 konsantre olur (satlr) gibi); daha fazla saflatrma /% 85 konsantre sikloheksan / pentanlarn sikloheksana izomerletirilmesini, açk zincirli hidrokarbonlarn çkarlmas için s krlmasnn ve aromatik bileiklerin çkarlmas için sülfürik asit muamelesinin yaplmasn gerektirir. Cikloheksan, C6H12 moleküler formülüne sahip bir sikloalkandr. Sikloheksan, temizlik ürünlerini hatrlatan (bazen içinde kullanld), belirgin bir deterjan benzeri kokusu olan renksiz, yanc bir svdr. Sikloheksan esas olarak adipik asit ve kaprolaktamn endüstriyel üretimi için kullanlr, ancak tepkisiz olmasna ramen, sikloheksan sikloheksanon ve sikloheksanol üretmek için katalitik oksidasyona urar. “KA ya” ad verilen sikloheksanon-sikloheksanol karm, naylonun öncüsü olan adipik asit ve kaprolaktam için bir hammaddedir. Ylda birkaç milyon kilogram sikloheksanon ve sikloheksanol üretilmektedir. [9]

Laboratuar çözücüsü ve dier ni kullanm alanlar. Baz düzeltme svs markalarnda çözücü olarak kullanlr. Sikloheksan bazen polar olmayan bir organik çözücü olarak kullanlr, bununla birlikte n-heksan bu amaç için daha yaygn olarak kullanlr. Pek çok organik bileik, scak sikloheksan içinde iyi çözünürlük ve düük scaklklarda zayf çözünürlük sergilediinden, sklkla yeniden kristalletirme çözücüsü olarak kullanlr.

Sikloheksan ayrca, -87.1 ° C’de uygun bir kristal-kristal geçii nedeniyle, diferansiyel taramal kalorimetri (DSC) cihazlarnn kalibrasyonu için kullanlr. [14]

Sikloheksan buhar, vakumla karbürletirme frnlarnda, sl ilem ekipman imalatnda kullanlr. naylonun öncüleridir. Endüstriyel bir ölçekte, bir Raney nikel katalizörü varlnda benzenin hidrojenlenmesi ile sikloheksan üretilir. [7] Sikloheksan üreticileri, benzen için küresel talebin yaklak% 11,4’ünü oluturmaktadr. [8] Tepkime (H (500 K) = -216,37 kJ / mol) ile oldukça ekzotermiktir. Dehidrojenasyon, hidrojen giderme için elverili entropiyi yanstan 300 ° C’nin üzerinde gözle görülür bir ekilde balamtr [9] Benzen-nikel katalizörü ile benzenin sikloheksana katalitik olarak hidrojenlenmesi. 6-köe kenar halkas mükemmel bir altgen ekline uymamaktadr. Düz bir 2D düzlem altgenin ekillenmesinde önemli aç gerginlii vardr, çünkü balar 109.5 derece deildir; burulma gerinimi de kayda deer olacaktr, çünkü bütün balar kapatlm balar olacakt. Bu nedenle, burulma gerilimini azaltmak için, sikloheksan, bir sandalye örtüsü olarak bilinen bir ilem vastasyla oda scaklnda hzl bir ekilde birbiriyle iç içe geçen, sandalye konformasyonu olarak bilinen üç boyutlu bir yapy benimser. Sandalye çevirme srasnda, karlalan dier üç ara konformasyon vardr: en dengesiz konformasyon olan yarm sandalye, daha stabil bot konformasyonu ve tekneyle daha stabil fakat yine de daha az sabit olan döner bot sandalyeden daha kararl. Sandalye ve büküm botu enerji minimumdur ve bu nedenle uyumludur, yarm sandalye ve tekne geçi durumudur ve enerji maksima’sn temsil eder. Sandalye konformasyonunun, sikloheksan için en stabil yap olduu fikri ilk önce Hermann Sachse tarafndan 1890 gibi önerildi, ancak daha sonra yaygn bir ekilde kabul gördü. Yeni konformasyon karbonlar 109,5 ° ‘lik bir açyla yerletirir. Hidrojenlerin yars halkann düzleminde (ekvator), dier yars da düzleme dik (eksenel). Bu konformasyon, en stabil sikloheksan yapsna izin verir. Bir baka sikloheksan konformasyonu, bot konformasyonu olarak da bilinir, ancak biraz daha kararl sandalye oluumuna dönüüm salar. Eer sikloheksan büyük bir sübstitüent ile mono sübstitüe edilmise, sübstitüent ekvator pozisyonunda eklenmi olarak bulunur, çünkü bu biraz daha kararl bir konformasyondur.

Sikloheksan, tüm sikloalkanlarn en düük açsna ve burulma suuna sahiptir; sonuç olarak, sikloheksann toplam halka geriliminde 0 olduu kabul edildi. Kat fazlar

Sikloheksann iki kristal faz vardr. 186 K ve erime noktas 280 K arasnda sabit olan yüksek scaklk faz I, plastik bir kristaldir, bu da moleküllerin dönme serbestlik derecelerini koruduu anlamna gelir. Düük scaklk (186 K alt) faz II sipari edilir. Dier iki düük scaklk (kararllkta olabilir) faz III ve IV, 30 MPa’nn üzerindeki orta basnçlarn uygulanmasyla elde edilmitir, burada faz IV sadece deuterated sikloheksanda ortaya çkar (basnç uygulamas tüm geçi scaklklarnn deerlerini arttrr. Sikloheksan oksidasyon tesisi, gösterilen ekil 2.55, bir katalizör mevcudiyetinde hava enjeksiyonu ile sikloheksann sikloheksanona ve sikloheksanole oksitlendii seri halinde alt reaktörden oluan bir trenden olumutur, tepkimeler ekzotermiktir, reaktörlere besleme taze bir sikloheksan ve geri dönütürülmü malzeme karmdr. Reaktörlerden gelen ürün hala yaklak% 94 orannda sikloheksan içermekte olup, sv reaktantlar bir reaktörden dierine yerçekimi ile akmaktadr, sonraki aamalarda, reaksiyon ürünü reaktörlere geri dönütürülmü olan reaksiyona girmemi sikloheksan ayrmak için damtlmtr ve Kaprolaktata dönütürülen sikloheksanon ve sikloheksanol, reaktördeki çalma koullar tasarm, 8.8 bar (g) ve 155 ° C idi. ekil 2-55’te gösterilen siklo-heksan oksidasyon tesisi, siklo-heksann siklo-heksanona ve siklo-heksanole oksitlendii seri halinde alt reaktörden oluan bir trenden oluuyordu. bir katalizör varlnda hava enjeksiyonu ile. Tepkimeler ekzotermiktir. Reaktörlere besleme, taze bir siklo-heksan ve geri dönütürülmü malzeme karmyd. Reaktörlerden gelen ürün hala yaklak yüzde 94 orannda siklo-heksan içermektedir. Sv reaktifler bir reaktörden dierine yerçekimi ile akmtr. Takip eden aamalarda, reaksiyon ürünü reaktörlere geri dönütürülen reaksiyona girmemi siklo-heksan ve kaprolaktam’a dönütürülen siklo-heksanon ve siklo-heksanolü ayrmak için damtld. Tasarma göre reaktörlerde çalma koullar 8,8 bar (g) ve 155 ° C idi. Sikloheksan / benzen / hidrojen sistemi, atmosferik basnçta 478-589K scaklk aralnda geri dönüümlü reaksiyonu içerir. Hem endotermik dehidrojenasyon hem de ekzotermik hidrojenasyon reaksiyonlar katalitik reaksiyonlardr. Reaksiyonun entalpisi çok büyük. Ayrca, benzenin hidrojenasyonu için teknoloji, kimyasal reaksiyon s depolamas için sikloheksan / benzen / hidrojen sisteminin potansiyel olarak uygulanmasn tevik edecek endüstriyel ölçekte [47] oluturulmutur. Bu nedenle, bu geri dönüümlü reaksiyon, kimyasal reaksiyon s depolamas için umut verici bir aday olarak kabul edilir. Reaktiflerdeki safszlklarn varl, bir yan reaksiyona neden olabilir. Safszlklar gidermek için reaktifleri ön ilemden geçirmek önemlidir. Cacciola ve di. [48], COP ve sikloheksan / benzen / hidrojen sistemi için çeitli etkili faktörler arasndaki ilikiyi aratrdlar. 473K’lk bir hidrojen giderme scakl ve 573K’lk hidrojenasyon scakl için, hem termal enerji depolama younluu hem de COP, hidrojen giderme ve hidrojenasyon reaksiyonlarnn reaksiyon dönüümleri srasyla% 30 ve% 70 olduunda en yüksek deere ulamtr. Besleme, sikloheksan, benzen, toluen içerir. ve o-ksilen. Ekstraksiyon çözücüleri olarak su ve aseton eklenir. Birinci ve ikinci sütunda (C1 ve C2), yüksek kaynama noktal bileenler (o-ksilen (3) ve toluen (6)), alt ürünler olarak çkarlr. Daha sonra, benzen (9) ve sikloheksan (12) distilat fraksiyonu olarak yakalanr. Benzen ve sikloheksan azeotrop oluturuyor ve yakn kaynama noktalarna sahip. Benzen, sikloheksan ile arlkça yaklak% 70 asetonda bir azeotrop oluturan aseton (7) eklenerek sikloheksandan ayrlr. Son olarak, bir çözücü olarak su (14) ilave edilerek sikloheksan bir ekstraksiyon aamasnda (El) asetondan uzaklatrlr. Ak 11 su, aseton ve sikloheksan izlerini içerir ve C5 sütununda ayrlr. Solventler aseton (13) ve su (14) geri dönütürülür.

Üretim

Modern üretim

Endüstriyel ölçekte, sikloheksan, benzenin hidrojenlenmesi ile üretilir. Sikloheksan üreticileri küresel benzen talebinin yaklak% 11,4’ünü oluturmaktadr. Reaksiyon, ΔH (500 K) = -216,37 kJ / mol) ile yüksek oranda ekzotermiktir. Dehidrojenasyon, dehidrojenasyon için elverili entropiyi yanstan 300 ° C’nin üzerinde belirgin bir ekilde balad.

Tarihsel yöntemler

Benzenin aksine, sikloheksan kömür gibi doal kaynaklarda bulunmaz. Bu nedenle, erken aratrmaclar sikloheksan örneklerini sentezledi.

Erken baarszlklar

1867’de Marcellin Berthelot yüksek scaklklarda hidrojeni asit ile benzen azaltmtr.

1870 ylnda, Adolf von Baeyer, reaksiyonu tekrarlad ve ayn reaksiyon ürünü “heksahidrobenzen” i ilan etti.

1890’da Vladimir Markovnikov, ayn bileii Kafkasya petrolünden damtp, onun karmn “hekzanaften” olarak adlandrdn düünüyordu.

artc bir ekilde sikloheksanlar, heksahidrobenzen veya heksanaftene göre 10 ° C daha yüksek kaynamaya balad, ancak bu bilmece 1895 ylnda Markovnikov, NM Kishner ve Nikolay Zelinsky tarafndan çözüldü, metilcyclopen “un” rejenere edilmesinin yeniden reaksiyona girmesiyle “heksahidrobenzen” ve “heksanaften” yeniden birletirildiinde, çözüldü. .

Tepkiler ve kullanmlar

Reaktif olmamakla birlikte, sikloheksan, sikloheksanon ve sikloheksanol üretmek için katalitik oksidasyona urar. “KA ya” ad verilen sikloheksanon-sikloheksanol karm, naylonun öncüsü olan adipik asit ve kaprolaktam için bir hammaddedir. Ylda birkaç milyon kilogram sikloheksanon ve sikloheksanol üretilir.

Laboratuar çözücüsü ve dier ni kullanmlar

Baz düzeltme svs markalarnda çözücü olarak kullanlr. Sikloheksan bazen polar olmayan bir organik çözücü olarak kullanlr, bununla birlikte n-heksan bu amaç için daha yaygn olarak kullanlr. Pek çok organik bileik, scak sikloheksan içinde iyi çözünürlük ve düük scaklklarda zayf çözünürlük sergilediinden, sklkla yeniden kristalletirme çözücüsü olarak kullanlr.

Sikloheksan ayrca, -87.1 ° C’de uygun bir kristal-kristal geçii nedeniyle diferansiyel taramal kalorimetri (DSC) cihazlarnn kalibrasyonu için kullanlr.

Ana madde: Sikloheksan konformasyonu

6 köeli kenar halkas, mükemmel bir altgen ekline uymuyor. Düz bir 2D düzlem altgenin yaps, balar 109.5 derece olmad için önemli bir aç gerginliine sahiptir; burulma gerilimi de kayda deer olurdu, çünkü bütün balar kapatlm balar olacakt. Bu nedenle, burulma gerilimini azaltmak için, sikloheksan, bir sandalye örtüsü olarak bilinen bir ilem vastasyla oda scaklnda hzl bir ekilde iç içe geçen, sandalye konformasyonu olarak bilinen üç boyutlu bir yapy benimser. Sandalye çevirme srasnda, karlalan dier üç ara konformasyon vardr: en dengesiz konformasyon olan yarm sandalye, daha stabil bot konformasyonu ve tekneyle daha stabil fakat yine de daha az sabit olan döner bot sandalyeden daha kararl. Sandalye ve büküm botu enerji minimatdr ve bu nedenle uyumludur, yarm sandalye ve bot geçi durumlardr ve enerji maksimasn temsil eder. Sandalye konformasyonunun, sikloheksan için en salam yap olduu fikri ilk önce Hermann Sachse tarafndan 1890 gibi önerildi, ancak daha sonra çok yaygn bir ekilde kabul gördü. Yeni konformasyon karbonlar 109.5 ° ‘lik bir açyla koyar. Hidrojenlerin yars halkann düzleminde (ekvator), dier yars da düzleme dik (eksenel). Bu konformasyon, en stabil sikloheksan yapsna izin verir. Bir tekne konformasyonu olarak bilinen bir baka sikloheksan yaps vardr, ancak biraz daha stabil sandalye oluumuna dönüüm salar. Eer sikloheksan büyük bir sübstitüent ile mono sübstitüe edilmise, sübstitüent ekvatorel bir konumda eklenmi olarak bulunacaktr, çünkü bu biraz daha kararl bir konformasyondur.

Sikloheksan tüm sikloalkanlarn en düük açsna ve burulma suuna sahiptir, sonuç olarak sikloheksan toplam halka suunda 0 olarak kabul edilmitir.

Kat fazlar

Sikloheksann iki kristal faz vardr. 186 K ve erime noktas 280 K arasnda sabit olan yüksek scaklk faz I, plastik bir kristaldir; bu, moleküllerin dönme serbestlik derecesini koruduu anlamna gelir. Düük scaklk (186 K alt) faz II sipari edilir. Dier iki düük scaklk (kararllkta) faz III ve IV, 30 MPa’nn üzerindeki orta basnçlarn uygulanmasyla elde edilmitir; burada faz IV, sadece deuterated sikloheksan içinde ortaya çkar (basnç uygulamasnn tüm geçi scaklklarnn deerlerini arttrdna dikkat edin).

Sanayi Kullanm Alanlar

Tarmsal kimyasallar (böcek ilac olmayan)

Korozyon inhibitörleri ve kireç önleyici maddeler

Yaktlar ve yakt katk maddeleri

Fonksiyonel svlar (kapal sistemler)

Ara ürünler

Laboratuar kimyasallar

Yalayclar ve yalayc katk maddeleri

Bilinmiyor veya makul ekilde tespit edilebilir

Dier kategorilerde tanmlanmayan boya katklar ve kaplama katklar

Solventler (ürün formülasyonunun veya karmnn bir parças haline gelir)

Tüketici Kullanmlar

Yaptrclar ve szdrmazlk maddeleri

Tarm ürünleri (haere ilac olmayan)

Baka hiçbir yerde kapsanmayan yap / inaat malzemeleri

Yaktlar ve ilgili ürünler

Mürekkep, toner ve renklendirici ürünler

Yalar ve gresler

Bilinmiyor veya makul ekilde tespit edilebilir

Boya ve kaplama

Petrokimya

kolej ve üniversite laboratuvar aratrmalar, dier kimyasal preparatlar, laboratuvar kullanm, Farmasötik preparat ve laboratuvar kullanm.

Güvenlik ve Tehlikeler

Tehlike TANITIMI

GHS Snflandrmas

GHS02: AlevlenirlerGHS07: Tahri ediciGHS08: Salk Tehlikesi, kanserojen, mutajenite, üreme toksisitesi, hedef organ toksisitesi, aspirasyon tehlikesiGHS09: Çevre, sucul toksisite

Sinyal: Tehlike

GHS Tehlike Beyanlar

Tehlike beyannamesi kodu olan 3406 irketin 3405’i tarafndan salanan 42 bildirimin:

H225 (% 100): Yüksek Alevlenir sv ve buhar [Tehlike Alevlenir svlar]

H304 (% 100): Yutulduunda ve hava yollarna girerse ölümcül olabilir [Tehlike Aspirasyon tehlikesi]

H315 (% 100): Cilt tahriine neden olur [Uyar Cilt anmas / tahrii]

H336 (% 99,32): Uyuuklua veya ba dönmesine neden olabilir [Uyar Belirli hedef organ toksisitesi, tek maruz kalma; Narkotik etkiler]

H400 (% 99.94): Sudaki yaam için çok toksik [Uyar Sudaki çevre için tehlikeli, akut tehlike]

H410 (98.68%): Uzun süreli etkilerle sudaki yaam için çok toksik [Uyar Sudaki çevre için tehlikeli, uzun süreli tehlike]

Bilgi kirliliklere, katk maddelerine ve dier faktörlere bal olarak bildirimler arasnda deiebilir. Parantez içindeki yüzde deeri, tehlike kodlar salayan irketlerden bildirilmi snflandrma orann gösterir. Sadece% 10’un üzerinde yüzde deerine sahip tehlike kodlar gösterilmektedir.

Konformasyon yaps

Hermann Sachse basit bir asistand. Çok iyi bir kimyac deildi ve iyi tannmyordu. Ancak, sikloheksann yapsn belirlemek için bir formül gelitirdi. Ancak zamannn kimyagerleri, imdi sandalye konformasyonu olarak bilinen bu yapy anlayamadlar. 31 yan altnda, fikirleri gülünç olduu için öldü. 25 yl boyunca bilim adamlar fikirlerinin meru olduunu kefettiler. Günümüzde sandalye düzenlemeleri, 6 üyeli halkalarn konformasyonunu göstermenin en kesin yoludur.

Sikloheksan Yaps ve Formülü

Sikloheksan, C6H12 kimyasal formülüne sahiptir. Bir halka oluturur, bu yüzden hiçbir CH3 ucu yoktur, bunun yerine her karbon bir CH2’ye balanr. Sikloheksan çekmenin en basit yolu basitçe altgen çizmektir. Bu formata göre, her nokta tamamen doymu (hidrojen atomlu) bir karbonu gösterir. Sikloheksan bu ekilde gösterildiinde, her bir karbon atomu ve her bir hidrojen atomu tamamen ayn görünür.

Siklohekseksan genellikle düz altgen eklinde çizilir.

Düz sikloheksan

Sikloheksan Konformasyonu

Hermann Sachse’nin gelitirdii konformasyona bugün sandalye konformasyonu denir. Sk sk düz bir altgen olarak sikloheksan çizmemize ramen, bu teknik olarak doru bir konformasyon deildir. Karbon atomlar 109.5 derecelik ba açlar oluturmay sever. Bu ba açs karbon atomlarn birbirine karmadan mümkün olduunca yakn tutar. Fakat eer sikloheksan düz altgen olsayd, ba açs 120 derece olurdu. Çarpk bir altgen oluturarak, ba açlar ideal 109.5 derece olur.

Hidrojen Atomlar

Tipik olarak altgen veya herhangi bir düz moleküle ikame maddeleri çizdiimizde, ikame edicinin aaya iaret ettiini belirtmek için noktal çizgiler kullanrz ve yukar dönük olduunu göstermek için kamalar kullanrz. Bu sandalye konformasyonunda noktal çizgiler ve kamalar kullanlmaz. Bunun yerine bir çizgiyi yukar bakacak ekilde, ikame edicinin yukary gösterdiini gösterirken aaya doru iaret eden bir satr aaya dönük olduunu gösterir. Oldukça yalndr. Ancak, her bir yer sadece yukar veya aa konuma sahip deildir, ayn zamanda ekvatoral veya ekseneldir. Ekvator, çizdiimiz orijinal çizgilere diktir ve eksenel açldr. Hem ekvator hem de eksenel ya yukar ya da aa olabilir, aslnda sandalyenin etrafnda ileri geri geçi yaparlar.

Açklama

Bu bileik, selüloz eterleri, cilalar, reçineleri, yalar, vakslar, yalar, bitümleri ve ham kauçuu çözmek için bir çözücü olarak kullanlr. Parfüm imalatnda, yüzey kaplama ilemleri srasnda (vernik), naylon 66 ve mühendislik plastikleri üretimi için adipik asit sentezinde, naylon 6’da kaprolaktam sentezi srasnda, boya ve vernik sökücüsünde, uçucu yalarn çkarlmasnda, moleküler arlk tayinleri için analitik kimyada, adipik asit, benzen, sikloheksil klorür, nitrosikloheksan, sikloheksanol ve sikloheksanon imalatnda, kamp sobalar için kat yakt üretiminde, fungisidal formülasyonlarda (hafif mantar öldürücü etkiye sahiptir) Steroidler, organik sentez, yeniden kristalize orta cam ikameleri, kat yaktlar, analitik kimyada ve yaptrclarn imalatnda.

Sikloheksann Yaplar

Sikloheksan için düzlemsel bir yap açkça imkanszdr. Ba açlar mutlaka ideal tetrahedral açsndan 120º, 10.5º daha büyük olacaktr. Ayrca, böyle bir yapdaki her karbon-karbon ba tutulur. Elde edilen aç ve tutulma sular bu yapy ciddi ekilde dengesizletirir. Alt üyeli halkann kar taraflarndaki iki karbon atomu halka düzleminden kaldrlrsa, aç gerginliinin büyük ksm elimine edilebilir.

Bu tekne yapsnn hala iki kapal ba ve teknenin “yay” ve “kç” nda iki hidrojen atomunun ar sterik kalabal vardr. Bu sterik kalabala genellikle sterik engel denir. Tekne konforunu bükerek, sterik engel ksmen giderilebilir, ancak döner bot conformer hala tekne conformer’ karakterize eden baz sular tutar. Son olarak, bir karbonu halka düzleminin üstüne ve dier düzlemin altna kaldrarak nispeten gergin bir ‘sandalye’ konformeri oluur. Bu, sikloheksan molekülleri tarafndan benimsenen baskn yapdr.

Sikloheksann konformasyonu ile ilgili aratrmalar, H. Sachse (1890) ve E. Mohr (1918) tarafndan balatlmtr, ancak 1950 ylna kadar, dönüümlü sandalye uyumlatrclarnn manifold sonuçlarnn tam bir muamelesinin ve askda kalan tahvillerin farkl yönelimlerinin açkland görülmemitir DHR Barton (Nobel Ödülü 1969, O. Hassel ile birlikte). Aadaki tartma bu konformasyonel analizin baz temel özelliklerini sunmaktadr.

Bir sandalyenin sikloheksan konformasyonunun dikkatlice incelenmesi üzerine, on iki hidrojenin yapsal olarak edeer olmadn tespit ettik. Bunlardan alt tanesi karbon halkann çevresine yerletirilmi ve ekvator olarak adlandrlmtr. Dier alt halka yüzüün yaklak düzleminin yukarsna ve altna (her bir konumdaki üç) yönlendirilir ve yüzüün simetri eksenine paralel olarak hizalandndan eksenel olarak adlandrlr.

FZKSEL VE KMYASAL BLGLER

Fiziksel durum; Görünüm

KARAKTERSTK KOKULU, RENKSZ SIVI.

Fiziksel tehlikeler

Buhar havadan ardr ve zeminde hareket edebilir; uzak tutuma mümkün. Ak, çalkalama vb. Bir sonucu olarak, elektrostatik yükler üretilebilir.

Kimyasal tehlikeler

Istma iddetli yanma veya patlamaya neden olabilir. Güçlü oksidanlarla reaksiyona girer.

Formül: C6H12

Moleküler kütle: 84.2

Kaynama noktas: 81 ° C

Erime noktas: 7 ° C

Bal younluk (su = 1): 0,8

Suda çözünürlük, g / 100ml, 25 ° C: 0.0058 (çok zayf)

Buhar basnc, 20 ° C’de kPa: 10.3

Bal buhar younluu (hava = 1): 2.9

Buhar / hava karmnn 20 ° C’de nispi younluu (hava = 1): 1.2

Parlama noktas: -18 ° C c.c.

Kendiliinden tutuma scakl: 260 ° C

Patlayc limitler, havadaki% hacim: 1.3-8.4

Log olarak oktanol / su ayrlma katsays Pow: 3.4

Viskozite: 26 ° C’de 1,26×10-6 mm² / s

MARUZ KALMA VE SALIK ETKLER

Maruz kalmann yollar

Bu madde buharnn solunmas ve yutulmas ile vücuda absorbe edilebilir.

KISA SÜREL MARUZ KALMA ETKLER:

Bu madde gözleri, cildi ve solunum sistemini hafifçe tahri eder. Bu madde merkezi sinir sistemini etkileyebilir. Bu sv yutulursa, akcierlere aspirasyon kimyasal pnömoniye neden olabilir. Maruz kalma bilinç kaybna neden olabilir.

Soluma riski

Bu maddenin 20 ° C de buharlamas üzerine havann zararl bir kirlenmesine çok hzl bir ekilde ulalabilir.

UZUN SÜRE VEYA TEKRARLAMALI MARUZ KALMA ETKLER:

Ciltle tekrar tekrar veya uzun süreli temas kurulua ve çatlama ve dermatite neden olabilir.

SPILLAGE DISPOSAL SINIFLANDIRMA VE ETKETLEME

Tehlikeli bölgeyi boaltn! Bir uzmana dann! Tüm ateleme kaynaklarn uzaklatrn. Kiisel korunma: kendi kendine yeten solunum cihaz. Havalandrma. Bu kimyasaln çevreye girmesine izin vermeyin. Szan ve dökülen svy mümkün olduu kadar szdrmaz kaplarda toplayn. Kalan svy kumda veya inert emici olarak eminiz. Ardndan yerel düzenlemelere göre saklayn ve atn. Kanalizasyona ykamayn.

BM GHS Kriterlerine Göre

flam; flameexcl mark; warncancer; salk hazenviro; aqua

TEHLKE

Yüksek derecede yanc sv ve buhar

Göz tahriine neden olur

Hafif cilt tahriine neden olur

Uyuuklua ve ba dönmesine neden olabilir

Yutulduunda ve hava yollarna girerse ölümcül olabilir.

Sucul ortamda uzun süre kalc, çok toksik etki.

tamaclk

BM Snflandrmas

BM Tehlike Snf: 3; BM Paket Grubu: II

DEPOLAMA

Yanmaz. Yangn söndürme ileminden kaynaklanan atk sular içeren hükümler. Güçlü oksidanlardan ayr depolaynz. Kanalizasyon veya kanalizasyon eriimi olmayan bir alanda saklayn.

LK YARDIM

GÖZLER: Önce kurban kontak lensleri açsndan kontrol edin ve varsa çkarn. Hastane gözlerini suyla veya normal tuzlu su çözeltisiyle 20 ila 30 dakika ykayn ve ayn anda bir hastane veya zehir kontrol merkezini arayn. Bir doktorun özel bir talimat olmadan kurbann gözlerine merhem, ya veya ilaç koymayn. HEMEN Herhangi bir semptom (kzarklk veya tahri gibi) olumasa bile, gözü ykadktan sonra kurban hastaneye götürün.

CLT: HEMEN bulam cildi suyla ykarken tüm kirli giysileri çkarr ve izole eder. Etkilenen tüm cilt bölgelerini nazikçe sabun ve suyla ykayn. Kzarklk veya tahri gibi semptomlar ortaya çkarsa, HEMEN bir doktora bavurun ve kurban tedavi için bir hastaneye nakletmeye hazr olun.

Teneffüs: HEMEN kirli bölgeyi terk edin; derin temiz hava al. Semptomlar (örnein hlma, öksürme, nefes darl veya azda, boazda veya göüste yanma gibi), bir doktora bavurun ve kurban hastaneye götürmek için hazrlkl olun. Bilinmeyen bir atmosfere giren kurtarclara uygun solunum korumas salayn. Mümkün olduunda, Müstakil Solunum Cihaz (SCBA) kullanlmaldr; mevcut deilse, Koruyucu Giysiler kapsamnda tavsiye edilenden daha büyük veya ona eit bir koruma kullann.

YUTMA: Kusturmaya ÇALIMAYIN. Uçucu kimyasallar, kusma srasnda tbbi sorunlar arttran kusma srasnda kurbann cierlerine aspire olma riski tamaktadr. Eer madur bilinçliyse ve sarslmazsa, kimyasallar seyreltmek için 1 veya 2 bardak su verin ve HEMEN bir hastane veya zehir kontrol merkezi arayn. HEMEN kurban hastaneye götür. Eer kurban sarslyorsa veya bilinçsizse, az yoluyla herhangi bir ey vermeyin, kurbann hava yolunun açk olduundan emin olun ve kurban bann vücudundan daha alçakta yanna koyun. Kusmaya karar vermeyin. HEMEN kurban hastaneye götür. (NTP, 1992)

Kimyasal formül:

C6H12

Parlama Noktas: -4 ° F (NTP, 1992)

Alt Patlama Snr (LEL):% 1.3 (NTP, 1992)

Üst Patlayc Snr (UEL):% 8,4 (NTP, 1992)

Kendiliinden tutuma scakl: 518 ° F (USCG, 1999)

Erime Noktas: 43.7 ° F (NTP, 1992)

Buhar Basnc: 68 ° F’de 95 mm Hg; 77.9 ° F’de 100 mm Hg (NTP, 1992)

Buhar Younluu (Havaya Göre): 2.9 (NTP, 1992)

Özgül Arlk: 68 ° F’da 0,779 (USCG, 1999)

Kaynama Noktas: 760 mm Hg’de 177.3 ° F (NTP, 1992)

Moleküler arlk: 84.16 (NTP, 1992)

Suda Çözünürlük: 63 ° F’da 1 mg / mL’den az (NTP, 1992)

yonlama Potansiyeli: 9.88 eV (NIOSH, 2016)

IDLH: 1300 ppm Düük patlayc limitinin% 10’una dayanarak

Yangnla Mücadele Tedbirleri

Ate:

Parlama noktas: -18C (0F) CC

Kendiliinden tutuma scakl: 245C (473F)

Hacimce% havadaki yanc limitler:

1: 1.3; uel: 8.0

Son derece yanc.

Patlama:

Parlama noktasnn üstünde, buhar-hava karmlar yukarda belirtilen yanc snrlar içinde patlaycdr. Buharlar, uzak tutuma kaynana ulamak için yüzeyler boyunca akabilir ve geri tepebilir. Kapal kaplar stldnda patlayabilir. Güçlü oksitleyicilerle temas yangna neden olabilir. Statik boalmaya kar duyarldr.

Yangn Söndürme Ortam:

Kuru kimyasal, köpük veya karbondioksit. Su etkisiz olabilir. Yangna maruz kalan kaplar souk tutmak, dökülmeleri yanmaz karmlara seyreltmek, sznty durdurmaya çalan personeli korumak ve buharlar datmak için su spreyi kullanlabilir.

Özel bilgi:

Yangn çkmas durumunda, tam bir koruyucu kyafet ve basnç talebinde veya dier pozitif basnç modunda çaltrlan tam ön cepheli NIOSH onayl bamsz solunum cihaz kullann. Bu yüksek derecede yanc sv, kvlcmlardan, açk alevden, scak yüzeylerden ve tüm s ve tutuma kaynaklarndan korunmaldr.

Kazalara KARI ALINACAK ÖNLEMLER

Sznt veya dökülme alann havalandrn. Tüm tutuma kaynaklarn uzaklatrn. Bölüm 8’de belirtilen uygun kiisel koruyucu ekipman kullann. Tehlike alann izole edin. Gereksiz ve korunmasz personelin girmesini önleyin. Mümkünse svy aln ve geri kazann. Kvlcm çkarmayan aletler ve ekipman kullann. Svy uygun bir kapta toplayn veya inert bir materyalle (örn., Vermikülit, kuru kum, toprak) absorbe edin ve kimyasal bir atk kabna yerletirin. Testere tozu gibi yanc malzemeler kullanmayn. Kanalizasyona ykamayn! Bir sznt veya dökülme tutumamsa, buhar datmak, sznty durdurmaya çalan personeli korumak ve dökülmeleri pozlardan uzak tutmak için su spreyi kullann. ABD Düzenlemeleri (CERCLA) bildirilebilir miktarlar aan topraa, suya ve havaya sznt ve salnmlarn bildirilmesini gerektirir. ABD Sahil Güvenlik Ulusal Müdahale Merkezi’nin ücretsiz numaras (800) 424-8802.

TAIMA VE DEPOLAMA

Fiziksel hasara kar koruyun. Serin ve kuru, iyi havalandrlan bir yerde, yangn tehlikesinin akut olabilecei yerlerden uzakta saklayn. Dta veya ayrk depolama tercih edilir. Uyumsuzluklardan ayr tutunuz. Statik kvlcm olumamas için transferler birletirilmeli ve topraklanmaldr. Depolama ve kullanm alanlar sigara içilmez alan olmaldr. Patlamaya dayankl havalandrma dahil, kvlcm çkarmayan tipte araç ve gereç kullann. Bu malzemenin kaplar, ürün kalntlarn (buharlar, svlar) tuttuklar için bo olduklarnda tehlikeli olabilir; Ürün için listelenen tüm uyar ve önlemlere uyun.

Maruz kalma kontrolleri / kiisel korunma

Havadaki Maruz Kalma Snrlar:

-OSHA zin Verilen Maruz Kalma Snr (PEL): 300 ppm (TWA)

-ACGIH Eik Snr Deeri (TLV): 100 ppm (TWA)

Havalandrma sistemi:

Çalanlarn Havadaki Maruz Kalma Snrlarnn altnda kalmas için yerel ve / veya genel bir egzoz sistemi önerilir. Yerel egzoz havalandrmas genellikle tercih edilir çünkü kirletici maddenin emisyonlarn kaynanda kontrol ederek genel çalma alanna yaylmasn önler. Lütfen ayrntlar için ACGIH belgesine baknz, Endüstriyel Havalandrma, Tavsiye Edilen Uygulamalar El Kitab, en son basm.

Kiisel Solunum Maskeleri (NIOSH Onayland):

Maruz kalma snr alrsa ve mühendislik kontrolleri uygun deilse, organik buhar kartulu tam yüz maskesi, maruz kalma limitinin 50 katna veya uygun düzenleyici kurum veya solunum cihaz tedarikçisi tarafndan belirtilen maksimum kullanm konsantrasyonuna (hangisi en düükse) kadar giyilebilir. Maruz kalma seviyelerinin bilinmedii acil durumlar veya durumlar için, tam yüz pozitif basnçl, hava beslemeli bir solunum cihaz kullann. UYARI: Hava temizleyici solunum aygtlar, çalanlar oksijensiz ortamlarda korumaz.

Cilt koruma:

Deri temasn önlemek için uygun ekilde botlar, eldivenler, laboratuvar önlüü, önlük veya tulumlar dahil koruyucu giysiler giyin.

Göz korumas:

Sçramann mümkün olduu yerlerde kimyasal güvenlik gözlükleri ve / veya tam yüz korumas kullann. Çalma alannda göz ykama çemesini ve hzl kaz tesislerini koruyun.

Cyclohexane is a cycloalkane with the molecular formula C6H12. Cyclohexane is mainly used for the industrial production of adipic acid and caprolactam, which are precursors to nylon. Cyclohexane is a colourless, flammable liquid with a distinctive detergent-like odor, reminiscent of cleaning products (in which it is sometimes used).

Cyclohexane is a cycloalkane with the molecular formula C6H12. Cyclohexane is a colourless, flammable liquid with a distinctive detergent-like odor, reminiscent of cleaning products (in which it is sometimes used). Cyclohexane is mainly used for the industrial production of adipic acid and caprolactam, which are precursors to nylon.

Production

Modern production

On an industrial scale, cyclohexane is produced by hydrogenation of benzene. Producers of cyclohexane accounts for approximately 11.4% of global demand for benzene. The reaction is highly exothermic, with ΔH(500 K) = -216.37 kJ/mol). Dehydrogenation commenced noticeably above 300 °C, reflecting the favorable entropy for dehydrogenation.

Historical methods

Unlike benzene, cyclohexane is not found in natural resources such as coal. For this reason, early investigators synthesized their cyclohexane samples.

Early failures

In 1867 Marcellin Berthelot reduced benzene with hydroiodic acid at elevated temperatures.

In 1870, Adolf von Baeyer repeated the reaction and pronounced the same reaction product “hexahydrobenzene”

in 1890 Vladimir Markovnikov believed he was able to distill the same compound from Caucasus petroleum, calling his concoction “hexanaphtene”.

Surprisingly their cyclohexanes boiled higher by 10 °C than either hexahydrobenzene or hexanaphtene but this riddle was solved in 1895 by Markovnikov, N.M. Kishner, and Nikolay Zelinsky when they reassigned “hexahydrobenzene” and “hexanaphtene” as methylcyclopentane, the result of an unexpected rearrangement reaction.

Reactions and uses

Although rather unreactive, cyclohexane undergoes catalytic oxidation to produce cyclohexanone and cyclohexanol. The cyclohexanone-cyclohexanol mixture, called “KA oil”, is a raw material for adipic acid and caprolactam, precursors to nylon. Several million kilograms of cyclohexanone and cyclohexanol are produced annually.

Laboratory solvent and other niche uses

It is used as a solvent in some brands of correction fluid. Cyclohexane is sometimes used as a non-polar organic solvent, although n-hexane is more widely used for this purpose. It’s frequently used as a recrystallization solvent, as many organic compounds exhibit good solubility in hot cyclohexane and poor solubility at low temperatures.

Cyclohexane is also used for calibration of differential scanning calorimetry (DSC) instruments, because of a convenient crystal-crystal transition at -87.1 °C.

Conformation

Main article: Cyclohexane conformation

The 6-vertex edge ring does not conform to the shape of a perfect hexagon. The conformation of a flat 2D planar hexagon has considerable angle strain because its bonds are not 109.5 degrees; the torsional strain would also be considerable because all of the bonds would be eclipsed bonds. Therefore, to reduce torsional strain, cyclohexane adopts a three-dimensional structure known as the chair conformation, which rapidly interconvert at room temperature via a process known as a chair flip. During the chair flip, there are three other intermediate conformations that are encountered: the half-chair, which is the most unstable conformation, the more stable boat conformation, and the twist-boat, which is more stable than the boat but still much less stable than the chair. The chair and twist-boat are energy minima and are therefore conformers, while the half-chair and the boat are transition states and represent energy maxima. The idea that the chair conformation is the most stable structure for cyclohexane was first proposed as early as 1890 by Hermann Sachse, but only gained widespread acceptance much later. The new conformation puts the carbons at an angle of 109.5°. Half of the hydrogens are in the plane of the ring (equatorial) while the other half are perpendicular to the plane (axial). This conformation allows for the most stable structure of cyclohexane. Another conformation of cyclohexane exists, known as boat conformation, but it interconverts to the slightly more stable chair formation. If cyclohexane is mono-substituted with a large substituent, then the substituent will most likely be found attached in an equatorial position, as this is the slightly more stable conformation.

Cyclohexane has the lowest angle and torsional strain of all the cycloalkanes, as a result cyclohexane has been deemed a 0 in total ring strain.

Solid phases

Industry Uses

Agricultural chemicals (non-pesticidal)

Corrosion inhibitors and anti-scaling agents

Fuels and fuel additives

Functional fluids (closed systems)

Intermediates

Laboratory chemicals

Lubricants and lubricant additives

Not known or reasonably ascertainable

Paint additives and coating additives not described by other categories

Solvents (which become part of product formulation or mixture)

Consumer Uses

Adhesives and sealants

Agricultural products (non-pesticidal)

Building/construction materials not covered elsewhere

Fuels and related products

Ink, toner, and colorant products

Lubricants and greases

Not known or reasonably ascertainable

Paints and coatings

Petrochemicals

college and university laboratory research, other chemical preparation, laboratory use, Pharmaceutical prep and laboratory use.

Safety and Hazards

Hazards Identification

GHS Classification

GHS02: FlammablesGHS07: IrritantGHS08: Health Hazard, carcinogen, mutagenicity, reproductive toxicity, target organ toxicity, aspiration hazardGHS09: Environment, aquatic toxicity

Signal: Danger

GHS Hazard Statements

Aggregated GHS information provided by 3406 companies from 43 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Reported as not meeting GHS hazard criteria by 1 of 3406 companies. For more detailed information, please visit ECHA C&L website

Of the 42 notification(s) provided by 3405 of 3406 companies with hazard statement code(s):

H225 (100%): Highly Flammable liquid and vapor [Danger Flammable liquids]

H304 (100%): May be fatal if swallowed and enters airways [Danger Aspiration hazard]

H315 (100%): Causes skin irritation [Warning Skin corrosion/irritation]

H336 (99.32%): May cause drowsiness or dizziness [Warning Specific target organ toxicity, single exposure; Narcotic effects]

H400 (99.94%): Very toxic to aquatic life [Warning Hazardous to the aquatic environment, acute hazard]

H410 (98.68%): Very toxic to aquatic life with long lasting effects [Warning Hazardous to the aquatic environment, long-term hazard]

Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown.

Conformation Structure

Hermann Sachse was a simple assistant. He wasn’t a great chemist and he wasn’t well known. But he developed a formula to determine the structure of cyclohexane. But chemists of his time just couldn’t understand this structure, which is now known as the chair conformation. He died at the young age of 31, with his ideas being ridiculed. It wasn’t for another 25 years that scientists discovered that his ideas were legitimate. Today chair conformations are the most precise way for depicting the conformation of 6-membered rings.

Cyclohexane Structure and Formula

Cyclohexane has the chemical formula of C6H12. It forms a ring, so there are no CH3 ends, instead each carbon is attached to a CH2. The simplest way to draw cyclohexane is simply draw a hexagon. According to this format, each point depicts a fully saturated (with hydrogen atoms) carbon. When cyclohexane is depicted this way, each carbon atom and each hydrogen atom appears exactly the same.

Cyclohyexane is often drawn as a flat hexagon

Flat cyclohexane

Cyclohexane Conformation

The conformation that Hermann Sachse developed is today called the chair conformation. Although we often draw cyclohexane as a flat hexagon, this isn’t the technically correct conformation. Carbon atoms like to form bond angles of 109.5 degrees. This bond angle keeps the carbon atoms as close as possible without them interfering with each other. But if cyclohexane were in a flat hexagon the bond angle would be 120 degrees. By forming a warped hexagon, the bond angles become the ideal 109.5 degrees.

Hydrogen Atoms

Typically when we draw substituents on the hexagon, or any flat molecule, we use dotted lines to indicate the substituent is pointing down, and we use wedges to indicate it is pointing up. On this chair conformation, the dotted lines and wedges aren’t used. Instead a line pointing up indicates the substituent is pointing up, while a line pointing down indicates it is pointing down. Pretty straight forward. But each location doesn’t only have an up or down position, it is also either equatorial or axial. Equatorial is perpendicular to the original lines we drew while axial comes at an angle. Both equatorial and axial can be either up or down, in fact they alternate back and forth around the chair.

Description

This compound is used as a solvent to dissolve cellulose ethers, lacquers, resins, fats, waxes, oils, bitumen and crude rubber. It is also used in perfume manufacturing, during surface coating operations (lacquers), in synthesis of adipic acid for production of nylon 66 and engineering plastics, during synthesis of caprolactam in nylon 6, paint and varnish remover, in the extraction of essential oils, in analytical chemistry for molecular weight determinations, in the manufacturing of adipic acid, benzene, cyclohexyl chloride, nitrocyclohexane, cyclohexanol and cyclohexanone, in the manufacturing of solid fuel for camp stoves, in fungicidal formulations (possesses slight fungicidal action) in the industrial recrystallising of steroids, organic synthesis, recrystallising medium glass substitutes, solid fuels, in analytical chemistry and in manufacturing of adhesives.

Substance details

Substance name: Cyclohexane

CASR number: 110-82-7

Molecular formula: C6H12

Synonyms: hexamethylene; hexanaphthene; hexahydrobenzene, benzenehexahydride

Physical properties

Cyclohexane is a colourless, mobile liquid with a mild, sweet odour. It is slightly soluble in water and soluble in alcohol, acetone, benzene, ethanol, ethyl ether, olive oil, and carbon tetrachloride.

Melting Point: 6.47°C

Boiling Point: 80.7°C

Specific Gravity: 0.779

Vapour Density: 2.98

1 ppm = 3.44 mg/m3

Formula weight 84.161

Chemical properties

Cyclohexane is a flammable, non-corrosive liquid.

Further information

The National Pollutant Inventory (NPI) holds data for all sources of cyclohexane emissions in Australia.

Cyclohexane

Cyclohexane (also known as CYX, hexamethylene, hexahydrobenzene, hexanaphthene, and benzenehexahydride) is a colourless, volatile, and flammable liquid with the formula C6H12. It has a mild odour and is insoluble in water but soluble in alcohol, ether, acetone, benzene, and ligroin. Cyclohexane occurs naturally in petroleum crude oil, volcanic gases and cigarette smoke.

Cyclohexane

Production

Industrial cyclohexane can be produced by two methods. The first is the catalytic hydrogenation of benzene using rhodium on carbon, and the second method is via fractional distillation of petroleum.

Storage and Distribution

Uses

Cyclohexane is used predominately in the nylon industry where approximately 90% of it is consumed in the industrial production of adipic acid and caprolactam, which are themselves used to generate nylon6 and nylon6.6. The remaining 10% is used both as a solvent for paints, resins, varnish and oil, and as a plasticiser. Cyclohexane can also be used as an intermediate in the manufacture of other industrial chemicals such as cyclohexanone and nitrocyclohexanone.

Conformations of Cyclohexane

A planar structure for cyclohexane is clearly improbable. The bond angles would necessarily be 120º, 10.5º larger than the ideal tetrahedral angle. Also, every carbon-carbon bond in such a structure would be eclipsed. The resulting angle and eclipsing strains would severely destabilize this structure. If two carbon atoms on opposite sides of the six-membered ring are lifted out of the plane of the ring, much of the angle strain can be eliminated.

This boat structure still has two eclipsed bonds and severe steric crowding of two hydrogen atoms on the “bow” and “stern” of the boat. This steric crowding is often called steric hindrance. By twisting the boat conformation, the steric hindrance can be partially relieved, but the twist-boat conformer still retains some of the strains that characterize the boat conformer. Finally, by lifting one carbon above the ring plane and the other below the plane, a relatively strain-free ‘chair’ conformer is formed. This is the predominant structure adopted by molecules of cyclohexane.

Investigations concerning the conformations of cyclohexane were initiated by H. Sachse (1890) and E. Mohr (1918), but it was not until 1950 that a full treatment of the manifold consequences of interconverting chair conformers and the different orientations of pendent bonds was elucidated by D. H. R. Barton (Nobel Prize 1969 together with O. Hassel). The following discussion presents some of the essential features of this conformational analysis.

On careful examination of a chair conformation of cyclohexane, we find that the twelve hydrogens are not structurally equivalent. Six of them are located about the periphery of the carbon ring, and are termed equatorial. The other six are oriented above and below the approximate plane of the ring (three in each location), and are termed axial because they are aligned parallel to the symmetry axis of the ring.

PHYSICAL & CHEMICAL INFORMATION

Physical State; Appearance

COLOURLESS LIQUID WITH CHARACTERISTIC ODOUR.

Physical dangers

The vapour is heavier than air and may travel along the ground; distant ignition possible. As a result of flow, agitation, etc., electrostatic charges can be generated.

Chemical dangers

Heating may cause violent combustion or explosion. Reacts with strong oxidants.

Formula: C6H12

Molecular mass: 84.2

Boiling point: 81°C

Melting point: 7°C

Relative density (water = 1): 0.8

Solubility in water, g/100ml at 25°C: 0.0058 (very poor)

Vapour pressure, kPa at 20°C: 10.3

Relative vapour density (air = 1): 2.9

Relative density of the vapour/air-mixture at 20°C (air = 1): 1.2

Flash point: -18°C c.c.

Auto-ignition temperature: 260°C

Explosive limits, vol% in air: 1.3-8.4

Octanol/water partition coefficient as log Pow: 3.4

Viscosity: 1.26×10-6 mm²/s at 26°C

EXPOSURE & HEALTH EFFECTS

Routes of exposure

The substance can be absorbed into the body by inhalation of its vapour and by ingestion.

Effects of short-term exposure

The substance is mildly irritating to the eyes, skin and respiratory tract. The substance may cause effects on the central nervous system. If this liquid is swallowed, aspiration into the lungs may result in chemical pneumonitis. Exposure could cause lowering of consciousness.

Inhalation risk

A harmful contamination of the air can be reached rather quickly on evaporation of this substance at 20°C.

Effects of long-term or repeated exposure

Repeated or prolonged contact with skin may cause dryness and cracking and dermatitis.

SPILLAGE DISPOSAL CLASSIFICATION & LABELLING

Evacuate danger area! Consult an expert! Remove all ignition sources. Personal protection: self-contained breathing apparatus. Ventilation. Do NOT let this chemical enter the environment. Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations. Do NOT wash away into sewer.

According to UN GHS Criteria

flam;flameexcl mark;warncancer;health hazenviro;aqua

DANGER

Highly flammable liquid and vapour

Causes eye irritation

Causes mild skin irritation

May cause drowsiness and dizziness

May be fatal if swallowed and enters airways

Very toxic to aquatic life with long lasting effects

Transportation

UN Classification

UN Hazard Class: 3; UN Pack Group: II

STORAGE

Fireproof. Provision to contain effluent from fire extinguishing. Separated from strong oxidants. Store in an area without drain or sewer access.

First Aid

EYES: First check the victim for contact lenses and remove if present. Flush victim’s eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim’s eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. If symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be prepared to transport the victim to a hospital for treatment.

INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. If symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop, call a physician and be prepared to transport the victim to a hospital. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing.

INGESTION: DO NOT INDUCE VOMITING. Volatile chemicals have a high risk of being aspirated into the victim’s lungs during vomiting which increases the medical problems. If the victim is conscious and not convulsing, give 1 or 2 glasses of water to dilute the chemical and IMMEDIATELY call a hospital or poison control center. IMMEDIATELY transport the victim to a hospital. If the victim is convulsing or unconscious, do not give anything by mouth, ensure that the victim’s airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital. (NTP, 1992)

Above flash point, vapor-air mixtures are explosive within flammable limits noted above. Vapors can flow along surfaces to distant ignition source and flash back. Sealed containers may rupture when heated. Contact with strong oxidizers may cause fire. Sensitive to static discharge.

Fire Extinguishing Media:

Dry chemical, foam or carbon dioxide. Water may be ineffective. Water spray may be used to keep fire exposed containers cool, dilute spills to nonflammable mixtures, protect personnel attempting to stop leak and disperse vapors.

Special Information:

In the event of a fire, wear full protective clothing and NIOSH-approved self-contained breathing apparatus with full facepiece operated in the pressure demand or other positive pressure mode. This highly flammable liquid must be kept from sparks, open flame, hot surfaces, and all sources of heat and ignition.

Accidental Release Measures

Ventilate area of leak or spill. Remove all sources of ignition. Wear appropriate personal protective equipment as specified in Section 8. Isolate hazard area. Keep unnecessary and unprotected personnel from entering. Contain and recover liquid when possible. Use non-sparking tools and equipment. Collect liquid in an appropriate container or absorb with an inert material (e. g., vermiculite, dry sand, earth), and place in a chemical waste container. Do not use combustible materials, such as saw dust. Do not flush to sewer! If a leak or spill has not ignited, use water spray to disperse the vapors, to protect personnel attempting to stop leak, and to flush spills away from exposures. US Regulations (CERCLA) require reporting spills and releases to soil, water and air in excess of reportable quantities. The toll free number for the US Coast Guard National Response Center is (800) 424-8802.

Handling and Storage

Protect against physical damage. Store in a cool, dry well-ventilated location, away from any area where the fire hazard may be acute. Outside or detached storage is preferred. Separate from incompatibles. Containers should be bonded and grounded for transfers to avoid static sparks. Storage and use areas should be No Smoking areas. Use non-sparking type tools and equipment, including explosion proof ventilation. Containers of this material may be hazardous when empty since they retain product residues (vapors, liquid); observe all warnings and precautions listed for the product.

Exposure Controls/Personal Protection

Airborne Exposure Limits:

-OSHA Permissible Exposure Limit (PEL): 300 ppm (TWA)

-ACGIH Threshold Limit Value (TLV): 100 ppm (TWA)

Ventilation System:

A system of local and/or general exhaust is recommended to keep employee exposures below the Airborne Exposure Limits. Local exhaust ventilation is generally preferred because it can control the emissions of the contaminant at its source, preventing dispersion of it into the general work area. Please refer to the ACGIH document, Industrial Ventilation, A Manual of Recommended Practices, most recent edition, for details.

Personal Respirators (NIOSH Approved):

If the exposure limit is exceeded and engineering controls are not feasible, a full facepiece respirator with organic vapor cartridge may be worn up to 50 times the exposure limit or the maximum use concentration specified by the appropriate regulatory agency or respirator supplier, whichever is lowest. For emergencies or instances where the exposure levels are not known, use a full-facepiece positive-pressure, air-supplied respirator. WARNING: Air purifying respirators do not protect workers in oxygen-deficient atmospheres.

Skin Protection:

Wear impervious protective clothing, including boots, gloves, lab coat, apron or coveralls, as appropriate, to prevent skin contact.

Eye Protection:

Use chemical safety goggles and/or a full face shield where splashing is possible. Maintain eye wash fountain and quick-drench facilities in work area.

CYCLOHEXANE

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