HYPOPHOSPHOROUS ACID (HPOFOSFRZ AST)
SYNONYMS
Hypophosphorous acid ; Hypophosphorous asid ; Hypophosphorous Asit ; HYPOPHOSPHORUS ACID; HYPO PHOSPHORUS ACID; HYPOPHOSPORUS ACID ; HPOFOSFORUS; HYPOFOSFORUS AST; OKS AST; OXYACID; FOSFORUS; FOSFORUS ACID; HPOFOSFORUS; Hydroxy(oxo)-λ5-phosphane; hydrophosphorous acid; Hydroxy-λ5-phosphanone; Oxo-λ5-phosphanol; Oxo-λ5-phosphinous acid; Phosphonous acid (for minor tautomer); PHOSPHINIC; ACID; hypophosphorous; Dihydroxyphosphine; HYPOPHOSPHORIC ACID; HYPOPHOSPHORUS ACID; phosphinic acid 50%; HYPOPHOSPOROUS ACID; Hypophoaphoeous acid; HYPOPHOSPHOROUS ACID; Diphosphoric(IV) acid; H3PO2 ; CHEBI:29031; Hypophosphorous acid (NF); Hypophosphorous acid [NF]; Phosphinic Acids; Phosphinicacid; hydrophosphorous acid; hydroxyphosphine oxide; hypo phosphorous acid; hypo-phosphorous acid; hydroxy(oxo)phosphanium; Phosphonous acid (VAN); DEA Code 6797; hydrophosphorous acid; dihydridodioxophosphoric acid; H2PO(OH); Hypophosphorous acid (VAN); dihydridohydroxidooxidophosphorus; EINECS 228-601-5; hydrogen dihydridodioxophosphate(1-); MFCD02183592; NSC 41904; Hypophosphorus acid; hypophosphorous acid; oxyacid; oxygen acidor; thophosphorous acid; phosphorous acid; 50% w/w aqueous solution; Hypophosphorous acid ; Hypophosphorous asid ; Hypophosphorous Asit ; HYPOPHOSPHORUS ACID; HYPO PHOSPHORUS ACID; HYPOPHOSPORUS ACID ; HPOFOSFORUS; HYPOFOSFORUS AST; OKS AST; OXYACID; FOSFORUS; FOSFORUS ACID; HPOFOSFORUS; Hydroxy(oxo)-λ5-phosphane; hydrophosphorous acid; Hydroxy-λ5-phosphanone; Oxo-λ5-phosphanol; Oxo-λ5-phosphinous acid; Phosphonous acid (for minor tautomer); PHOSPHINIC; ACID; hypophosphorous; Dihydroxyphosphine; HYPOPHOSPHORIC ACID; HYPOPHOSPHORUS ACID; phosphinic acid 50%; HYPOPHOSPOROUS ACID; Hypophoaphoeous acid; HYPOPHOSPHOROUS ACID; Diphosphoric(IV) acid; H3PO2 ; CHEBI:29031; Hypophosphorous acid (NF); Hypophosphorous acid [NF]; Phosphinic Acids; Phosphinicacid; hydrophosphorous acid; hydroxyphosphine oxide; hypo phosphorous acid; hypo-phosphorous acid; hydroxy(oxo)phosphanium; Phosphonous acid (VAN); DEA Code 6797; hydrophosphorous acid; dihydridodioxophosphoric acid; H2PO(OH); Hypophosphorous acid (VAN); dihydridohydroxidooxidophosphorus; EINECS 228-601-5; hydrogen dihydridodioxophosphate(1-); MFCD02183592; NSC 41904; Hypophosphorus acid; hypophosphorous acid; oxyacid; oxygen acidor; thophosphorous acid; phosphorous acid; 50% w/w aqueous solution; Hipofosfor asit; Hipofosfor asidi; Hipofosfor Asit; HPOPOSFORUS AST; HPER PHOSPHORUS AST; HPOPOSFORUS AST; HPOFOSFORUS; HPOFOSFORUS AST; OKS AST; oxyacid; FOSFORUS; FOSFORUS ACID; HPOFOSFORUS; Hidroksi (okso) -λ5-fosfan; hidrofosfor asit; Hidroksi-λ5-phosphanone; Okso-λ5-phosphanol; Oxo-λ5-fosfinik asit; Fosfor asidi (küçük tatomerler için); fosfnik; AST; hipofosfor; Dihydroxyphosphine; HPOFOSFORK AST; HPOPOSFORUS AST; fosfinik asit% 50; HPOFOSPOROUS AST; Hipofosfor asit; HPOFOSFOROUS AST; Difosforik (IV) asit; H3P02; Chebi: 29031; Hipofosfor asit (NF); Hipofosfor asit [NF]; Fosfinik Asitler; Phosphinicacid; hidrofosfor asit; hidroksifosfin oksit; hipo fosfor asidi; hipo-fosfor asidi; hidroksi (okso) phosphanium; Fosfor asidi (VAN); DEA Kodu 6797; hidrofosfor asit; dihidridodioksifosforik asit; H2Po (OH); Hipofosfor asit (VAN); dihydridohydroxidooxidophosphorus; EINECS 228-601-5; hidrojen dihidridodioksofosfat (1-); MFCD02183592; NSC 41904; Hipofosfor asidi; hipofosfor asit; oxyacid; oksijen asidi; tofosfor asit; fosfor asidi; % 50 a / a sulu çözelti; hipofosfor. Hypophosphorus acid, 50% w/w aqueous solution Phosphinic acid, for synthesis, 49.5-50.5%; Hypophosphorous acid solution, 50 wt. % in H2O; J-521481; Phosphinic acid, puriss. p.a., 49.5-50.5% (alkalimetric); Hypophosphorous acid solution, SAJ first grade, 30.0-32.0% in H2O; Phosphinic acid, puriss., meets analytical specification of NF, 30-32%; HPOFOSFOROS AST; InChI=1S/HO2P/c1-3-2/h(H,1,2); GQZXNSPRSGFJLY-UHFFFAOYSA-N; hipofosföröz acit; hipofosföröz acide; hipofosforoz asde; hipofosforoz acid; hipofosforoz ast; hipofosforoz asit; hipofosforos asit; hipofosforos asit; 238U65NZ04; 8B1RL9B4ZJ; hipofos acide; hipofösförös asit; hipoföphosphenous acid; Hypophosphorus acid; UNII-238U65NZ04; 238U65NZ04; Phosphinic acid, ion(1-); hydroxyphosphanone; EINECS 270-204-4; INECS 270-206-5; Oxo-|E5-phosphanol; HOSPHINYLOXY; Hydroxidooxidophosphorus; Perfluoroalkyl (C6-C12) phosphonic acid; Diperfluoroalkyl (C6-C12) phosphinic acid; Hydroxy-|E5-phosphanone; AC1L2KHN; Oxo-|E5-phosphinous acid; dihydridodioxophosphate(1-); Phosphonic acid, perfluoro-C6-12-alkyl derivs; ACMC-1B7H2; Hypophosphorous acid solution; Hydroxy(oxo)-|E5-phosphane; dihydridodioxidophosphate(1-); [P(O)OH]; Phosphinic acid, bis(perfluoro-C6-12-alkyl) derivs; DTXSID4043808; CHEBI:29198; CHEBI:36363; NOCAS_43808; ACVYVLVWPXVTIT-UHFFFAOYSA-M; GQZXNSPRSGFJLY-UHFFFAOYSA-N; MolPort-009-199-230; NSC41904; PH2O2(-); MFCD02183592; NSC-41904; Hypophosphorous Acid, Phosphinic Acid; KOS028110018; [PH2O2](-); RL04397; RTR-021708; 68412-68-0; 68412-69-1; IN016101; KB-52532; SC-26114; TR-021708; FT-062644sförös acide; hipofösförös acid; hipofözföröz asit; hipofözföröz; Hypophosphorous acid solution; Synonym: Phosphinic acid; Linear Formula: H3PO2; Molecular Weight: 66.00; CAS Number: 6303-21-5; Hypophosphorous acid solution; 50 wt. % in H2O; Hypophosphorous acid-d3 solution; XRBCRPZXSCBRTK-CBYSEHNBSA-N; Hypophosphorous acid; 104633; H3O2P; 65.987068 Da; Hypophosphorous acid [NF] [Wiki]; 6303-21-5 [RN]; Acide phosphinique [French]; ACD/IUPAC Name]; H2PO(OH) [Formula]; Hypophosphorous acid (VAN); PH2(OH)O [Formula]; PH2O(OH) [Formula]; Phosphinic acid [ACD/Index Name] [ACD/IUPAC Name]; Phosphinsäure [German] [ACD/IUPAC Name]; [PH2(OH)O]; [PH2O(OH)]; dihydridodioxophosphoric acid; dihydridohydroxidooxidophosphorus; dihydroxyphosphanium; dihydroxyphosphonium; H3PO2; HPA; hydrophosphorous acid; Hypophosphorous acid solution; UNII:8B1RL9B4ZJ; UNII-8B1RL9B4ZJ; 次磷酸 [Chinese]; Hypophosphorous acid; hypophosphorous; PHOSPHINIC ACID; Dihydroxyphosphine; HYPOPHOSPHORIC ACID; HYPOPHOSPHORUS ACID; phosphinic acid 50%; HYPOPHOSPOROUS ACID; Hypophoaphoeous acid; HYPOPHOSPHOROUS ACID; Diphosphoric(IV) acid; CBNumber:CB6130318; Hypophosphorous acid solution 50wt. % in H; Hypophosphorous acid, 50% w/w aq. soln.; Acide phosphinique; Acido fosfinico; Dihydroxyphosphine; Hydroxyphosphine oxide; Hypophosphorous acid; Phosphine oxide, hydroxy-; Phosphinic acid; Phosphinsaure; Phosphonous acid; DIHYDROXYPHOSPHINE; HYDROXYPHOSPHINE OXIDE; HYPOPHOSPHOROUS ACID; PHOSPHINE OXIDE, HYDROXY-; PHOSPHONOUS ACID; Hypophosphorus acid; (Phosphonic acid) (6303-21-5); Hypophosphorous acid; Hypophosphorous acid 50%; extra pure; Hypophosphorous acid, 50 wt.% solution in water; Hypophosphorous Acid pure, 30-32% in water; Phosphinic acid; Phosphinic Acid; 次磷酸; Acide phosphinique (French); Phosphinsäure (German); ácido fosfínico (Spanish); DEA Code 6797; Phosphinic acid; hypophosphoric; hypophosphoric acid; hypophosphorous; hypophosphorous acid; hypophrygian; hypophyge; hypophysectomy; 60062-19-3; ECHA EINECS; REACH Pre-Reg:228-601-5; FDA UNII: 8B1RL9B4ZJ; MDL:MFCD02183592; XlogP3-AA:-0.70 (est); Molecular Weight:63.98013200; Formula:HO2 P; phosphenous acid; phosphine oxide, hydroxy-; phosphinic acid; phosphonous acid; CHEBI:8138; CHEBI:26042; dihydridodioxophosphoric acid; dihydridohydroxidooxidophosphorus; hydrogen dihydridodioxophosphate(1-); [PH2(OH)O; [PH2O(OH)] IUPAC; H2PO(OH) IUPAC; H3PO2 ChEBI; HPA; ChEBI; HPH2O2IUPAC; hydrophosphorous acid; ChEBI; Hypophosphorous acid; KEGG COMPOUND; Phosphinic acid; InChI=1S/H3O2P/c1-3-2/h3H2,(H,1,2); InChIKey; ACVYVLVWPXVTIT-UHFFFAOYSA-N; SMILES; [H]OP([H])([H])=O; hipofosforoz asit; asit; hipofosforoz; hipofösföröz; hipofosoforos;HIPOFOSFOROS; ASTE; HPOFÖSFÖRÖZ AST; HPOFÖSFÖRÖZ; hipopopfosforosasit; hipofosoforosacide; fosforosacid
HPOFOSFÖRÖZ AST, renksiz bir yal sv veya çözünen kristallerdir eki bir kokudur.
Younluk 1.439 g / cm3.
Erime noktas 26.5 ° C.
Inhalasyon buharlar solunum yollarn tahri eder veya yakar. Sv ve buhar tahri edebilir veya gözleri ve cildi yakabilir.
HPOFOSFÖRÖZ AST fosforik asit ve kendiliinden yanc fosfine stldnda ayrr. HPOFOSFOR ACT Sülfürik asit ile kükürt dioksit ve kükürt braklarak oksidize olur. HPOFOSFOR AST Cva (II) oksit ile patlayc bir reaksiyon gösterir Cva (II) nitratla iddetli reaksiyon gösterir. Egzotermik reaksiyonlarda bazlar nötralize eder.
Hipofosforöz asit, “hipofosfit” olarak da bilinir. Renksiz bir yadr veya Karm kristali, önemli bir ince kimyasal üründür. Ana reçinelerin renklenmesini önleyen fosforik, elektroliz kaplama için indirgeyici ajan olarak kullanlr, ayrca esterifikasyon reaksiyonu katalizörü, soutucu, özellikle yüksek saflkta ürün sodyum hipofosfit üretimi için de ullanlabilir. Hazrlama için çeitli yöntemler vardr, ortak endüstriyel üretim yöntemi iyon deiim reçine yöntemi ve elektrodiyaliz yöntemidir. Hipofosforöz asidin kimyasal özellikleri, kullanmlar, toksisitesi ve üretim yöntemleri Chemicalbook tarafndan düzenlenmitir.
Kimyasal özellikler
Hypophosphorous acid, delikatif kristaller veya renksiz bir yadr.
Erime noktas: 26.5 ?.
Nispi younluk (özgül arlk): 1.439 (kat, 19 ° C).
Hipofosfor asit, su, etanol ve eterde çözünür ve hipofosfor asidi, su, etanol, aseton ile herhangi bir oranda kartrlabilir.
Havada, hipofosforöz asit, uruplu svya kolaylkla karr ve Sulu Solüsyon asidiktir.
Hipofosfor asit monobazik asit, sulu çözelti halinde, hipofosforik asit güçlü asit, Ka = 10-2 (25 ° C); Hipofosfor asit nispeten oda Scaklnda kararl; orantszlama reaksiyonu 130 ° C’de balayabilir, Fosfin ve fosfor asidine ayrr:
2H3PO2 = H3PO4 + PH3
Hipofosforöz asit güçlü indirgeme özelliine sahiptir, ar metal tuzu Çözeltisi
Cu2 +, Hg2 +, Ag + gibi metallere geri döndürülür, örnein:
4AG + H3PO2 + 2H2) = 4AG + H3PO4 + 4H +
Hipofosforöz asit zayf oksitleyici, hipofosforöz asit indirgenebilir Fosfin, güçlü indirgeme ajan ile karlatnda fosfindir. Serbest hipofosforik asit, H3PO2, sulu çözeltilerin Hipofosfit iyonlarnn çözeltileri, H2PO2-. Örnein, kalan çözüm fosfin, beyaz fosfor ve bir bazn reaksiyonundan hazrlandnda H2PO2 iyonunu içerir. Eer baz olarak baryum hidroksit (BaOH) kullanlrsa ve solüsyon sülfürik asit, baryum sülfat, BaS04 ile asitletirilir, çökelir ve sulu bir hipofosforöz asit solüsyonu oluur.
Ba2 + + 2H2PO2- + 2H3O + + SO42- › BaS04 + 2H3PO2 + 2H2O
Saf asit, sadece suyun buharlamasyla izole edilemez, Hipofosforöz asidin fosforik oksit haline kolaylkla okside olmas nedeniyle asitler (ve elemental fosfor) ve fosfine orantszlamas ve fosfor asididir. Saf asit, sulu solüsyonunun dietil eter, (C2H5) 20 ile ekstraksiyonu ile elde edilebilir. Saf hipofosforöz asit, 26.5 ° C’de (79.7 ° F) eriyen beyaz kristalleri oluturur. Hipofosforöz asidin elektronik yaps oksijene bal yalnzca bir hidrojen atomuna sahip olduu eklindedir ve bu nedenle monoprotik bir oksiasittir. Hipofosforöz asit, zayf bir asittir ve sadece bir dizi tuz oluturur. Sulu sodyum hipofosfit, NaH2PO2 · H2O, endüstriyel özellikle metallerin ve ametallere nikelin elektrolizsiz kaplamas içindir.
KULLANIMLARI
1. Hipofosforos asit, elektroliz kaplama için indirgeyici ajan olarak kullanlr.
2. Hipofosforos asit, fosforiklerin renk deiimini önlemek için kullanlabilir asit reçinesiDR.
3. Hypophosphorous asit esterifikasyon katalizörü, soutucu olarak Kullanlr.
4. Hypophosphorous asit hipofosfit, sodyum tuzlar, manganez tuzlar, demir tuzlar genellikle besleyici maddeler olarak kullanlr.
5. Tbpte ve indirgeyici ajan olarak hipofosfor asit kullanlr; arsenik, tellüryum ve tantal, niyobyum ve dier reaktifler.
6. Hypophosphorous asit güçlü indirgeyici ajan, sodyum hipofosfit, kalsiyum fosfat ve dier hipofosfitlerin hazrlanmasdr.
7. Kaplama banyosu için hipofosforöz asit kullanlabilir.
8. Hypophosphorous asit güçlü indirgeyici ajan, yapmnda kullanlabilir sodyum hipofosfit, kalsiyum fosfat ve dier hipofosfittir.
9. Hipofosforöz asit, indirgeyici ajan, Ag, Cu, Ni, Hg ve dier metaller ilgili metale indirgenir, Nb, Ta ve dier ayraçlar olarak, Hipofosforöz asit, Na, K, Ca, Mn, Fe ve dier hipofosfit tiplerinin hazrlanmasdr.
Uygulamalar
Hypophosphorous asit öncelikle elektroliz nikel kaplama için kullanlr. Arenediazonyum tuzlarnn azaltlmasyla ilgilidir. Fischer esterifikasyon reaksiyonlarnda katk maddesi olarak ilev görür. Ayrca, nötrletirici bir ajan, antioksidan, polimerizasyon ve poli younlama katalizörü ve slatc ajan olarak görev yapmaktadr. Ayrca farmasötiklerin formülasyonunda, polimerlerin renk bozulmalarnda, suyun artlmasnda ve deerli veya demirsiz metallerin geri kazanlmasnda kullanlr. Buna ek olarak, kimyasallar ve birkaç plastik üretiminde plastik, sentetik elyaf, renk giderici ajan ve renk stabilizasyonu için aartma maddeleri olarak kullanlr.
HYPOPHOSPHOROUS ACID is a colorless oily liquid or deliquescent crystals with a sour odor. Density 1.439 g / cm3. Melting point 26.5°C. Inhalation of vapors irritates or burns the respiratory tract. Liquid and vapors may irritate or burn eyes and skin.
HYPOPHOSPHOROUS ACID decomposes when heated into phosphoric acid and spontaneously flammable phosphine. HYPOPHOSPHOROUS ACID Is oxidized by sulfuric acid with release of sulfur dioxide and sulfur. HYPOPHOSPHOROUS ACID Reacts explosively with mercury(II) oxide Reacts violently with mercury(II) nitrate. Neutralizes bases in exothermic reactions. Hypophosphorous acid (H3PO2) is also named dihydridohydroxidooxidophosphorus, phosphinic acid, or more commonly “HPA”. Our production is made by reacting sodium hypophosphite with sulphuric acid. Hypophosphorous acid (H3PO2) is sold as a 50% wt aqueous solution. It is a clear and colourless liquid which is a powerful reducing agent very used in the chemical industry.
Hypophosphorous acid is used in a wide range of applications such as the formulation of pharmaceuticals, discoloration of polymers, water treatment, retrieval of precious or non-ferrous metals, for instance. Its main use is for electroless plating, i.e. deposition of metal films from solutions.
Hypophosphorous acid is also known as “hypophosphite” It is colorless oil or deliquescence crystal , it is an important fine chemical product. The main use is as reducing agent for electroless plating, phosphoric prevent discoloration of resins, it can also be used in the esterification reaction catalyst, the refrigerant, in particular for the production of high purity product sodium hypophosphite. There are several methods for preparation, the common industrial method for producing is ion exchange resin method and electrodialysis method. The chemical properties of hypophosphorous acid, uses, toxicity, and production methods are edited by andy of Chemicalbook.
Chemical properties
Hypophosphorous acid is deliquescent crystals or colorless oil.
Melting point: 26.5?.
The relative density (specific gravity): 1.439 (solid, 19?).
Hypophosphorous acid is soluble in water, ethanol and ether, and Hypophosphorous acid can be mixed in any proportion with water, ethanol, acetone.
In the air, Hypophosphorous acid easily deliquesce to syrupy liquid, and the aqueous solution is acidic.
Hypophosphorous acid is monobasic acid, in aqueous solution, Hypophosphorous acid is strong acid, Ka = 10-2 (25?); Hypophosphorous acid is relatively stable at room temperature; disproportionation reaction can proceed at 130?, decompose into phosphine and phosphorous acid:
2H3PO2=H3PO4+PH3
Hypophosphorous acid has strong reduction, heavy metal salt solution can be restored to metals such as Cu2 +, Hg2 +, Ag +, such as:
4Ag+H3PO2+2H2)=4Ag+H3PO4+4H+
Hypophosphorous acid is weak oxidizer, Hypophosphorous acid can be reduced to phosphine, phosphine when encounters strong reducing agent.
Free hypophosphorous acid, H3PO2, is prepared by acidifying aqueous solutions of hypophosphite ions, H2PO2-. For example, the solution remaining when phosphine is prepared from the reaction of white phosphorus and a base contains the H2PO2- ion. If barium hydroxide (BaOH) is used as the base and the solution is acidified with sulfuric acid, barium sulfate, BaSO4, precipitates, and an aqueous solution of hypophosphorous acid results.
Ba2+ + 2H2PO2- + 2H3O+ + SO42- › BaSO4 + 2H3PO2 + 2H2O
The pure acid cannot be isolated merely by evaporating the water, however, because of the easy oxidation of the hypophosphorous acid to phosphoric acids (and elemental phosphorus) and its disproportionation to phosphine and phosphorous acid. The pure acid can be obtained by extraction of its aqueous solution by diethyl ether, (C2H5)2O. Pure hypophosphorous acid forms white crystals that melt at 26.5 °C (79.7 °F). The electronic structure of hypophosphorous acid is such that it has only one hydrogen atom bound to oxygen, and it is thus a monoprotic oxyacid. hypophosphorous acid is a weak acid and forms only one series of salts, the hypophosphites. Hydrated sodium hypophosphite, NaH2PO2 · H2O, is used as an industrial reducing agent, particularly for the electroless plating of nickel onto metals and nonmetals.
Hypophosphorous acid is the phosphorus oxo acid or hydroxy phosphine oxide, with monobasic character. The term phosphinic acid is for the descriptive presentation of derivatives or salts which hydrogen atoms bound to phosphorus are replaced by organic groups, called phosphinates. The term hypophosphite is also used for any salt, ester or anion derived from the name of hypophosphorous acid. Hypophosphorous acid is a low-melting point compound soluble in water. It is a powerful reducing agent. Hypophosphorous acid and its sodium salt (sodium hypophosphite) are used as powerful reducing agents in various field. (Hypophosphorous acid has an advantage of easy implementation in solution.)
USES
1. Hypophosphorous acid is used as reducing agent for electroless plating;
2. Hypophosphorous acid can be used to prevent discoloration of phosphoric acid resin;
3. Hypophosphorous acid is used as esterification catalyst, the refrigerant;
4. Hypophosphorous acid is used to produce hypophosphite, sodium salts, manganese salts, iron salts are generally used as nourishing substances;
5. Hypophosphorous acid is used in medicine and as reducing agent, the determination of arsenic, tellurium and separation of tantalum, niobium and other reagents.
6. Hypophosphorous acid is strong reducing agent, It can be used for the preparation of sodium hypophosphite, calcium phosphate and other hypophosphite.
7. Hypophosphorous acid can be used for the plating bath. Pharmaceuticals. reducing agent. general reagents.
8. Hypophosphorous acid is strong reducing agent, it can be used in making sodium hypophosphite, calcium phosphate and other hypophosphite.
9. Hypophosphorous acid is widely used as reducing agent, Ag, Cu, Ni, Hg and other metals are reduced to the corresponding metal, for the verification of As, Nb, Ta and other reagents, Hypophosphorous acid can be used for the preparation of Na, K, Ca, Mn, Fe and other types of hypophosphite.
Applications
Hypophosphorous acid is primarily used for electroless nickel plating. It is involved in the reduction of arenediazonium salts. It acts as an additive in Fischer esterification reactions. Also, it serves as a neutralizing agent, antioxidant, catalyst in polymerization and poly condensation, and wetting agent. Further, it is used in the formulation of pharmaceuticals, discoloration of polymers, water treatment and retrieval of precious or non-ferrous metals. In addition to this, it is used as bleaching agents for plastics, synthetic fibers, decolorizing agent and for color stabilization during the manufacture of chemicals and several plastics.
Hypophosphorous Acid is used in the production of Hypophosphite Salts (i.e., Calcium, Magnesium, Manganese, Potassium, Iron, and Ammonium) which are in turn used in synthetic fibers as wetting dispersing, emulsifying, and anti-static agents
Chemical Intermediate
Used in organic synthesis and organo phosphinic acid production
Neturalizing Agent
Used as a moderately strong monobasic acid
Catalyst
Used as a polymerization and polycondensation catalyst
Wetting Agent
Used as a wetting, dispersing, or emulsifying agent in electroplating
Reducing Agent
May be used for its strong but slow reducing action
Antioxidant
Hypophosphorous Acid may be used as an antioxidant
Pharmaceutical
HPA may be used as a stimulant in pharmaceuticals
Hypophosphorous acid (HPA), or phosphinic acid, is a phosphorus oxyacid and a powerful reducing agent with molecular formula H3PO2. It is a colorless low-melting compound, which is soluble in water, dioxane, and alcohols. The formula for this acid is generally written H3PO2, but a more descriptive presentation is HOP(O)H2, which highlights its monoprotic character. Salts derived from this acid are called hypophosphites.[3]
HOP(O)H2 exists in equilibrium with the minor tautomer HP(OH)2. Sometimes the minor tautomer is called hypophosphorous acid and the major tautomer is called phosphinic acid.
Contents
1 Preparation and availability
2 Reactions and uses
3 Organic chemistry
3.1 DEA List I chemical status
4 Organophosphinic acids (Phosphinates)
5 Inorganic derivatives
6 Sources
7 References
Preparation and availability
Hypophosphorous acid was first prepared in 1816 by the French chemist Pierre Louis Dulong (1785-1838).[4]
The acid is prepared industrially via a two step process: Firstly, hypophosphite salts of the alkali and alkaline earth metals result from the reaction of white phosphorus with hot aqueous solution of the appropriate hydroxide, e.g. Ca(OH)2.
P4 + 4 OH- + 4 H2O → 4 H
2PO-
2 + 2 H2
The salt is then treated with a strong, non-oxidizing acid to give the free hypophosphorous acid:
H
2PO-
2 + H+ → H3PO2
HPA is usually supplied as a 50% aqueous solution. Anhydrous acid cannot be obtained by simple evaporation of the water, as the acid ready oxidises to phosphorous acid and phosphoric acid and also disproportionates to phosphorous acid and phosphine. Pure anhydrous hypophosphorous acid can be formed by the continuous extraction of aqueous solutions with diethyl ether.[5]
Reactions and uses
Its main industrial use is for electroless nickel plating (Ni-P), although it is primarily used as a salt (sodium hypophosphite).[6]
Organic chemistry
In organic chemistry, H3PO2 can be used for the reduction of arenediazonium salts, converting ArN+
2 to Ar-H.[7][8][9] When diazotized in a concentrated solution of hypophosphorous acid, an amine substituent can be removed from arenes.
Owing to its ability to function as a mild reducing agent and oxygen scavenger it is sometimes used as an additive in Fischer esterification reactions, where it prevents the formation of colored impurities.
It is used to prepare phosphinic acid derivatives.[10]
DEA List I chemical status
Because hypophosphorous acid can reduce elemental iodine to form hydroiodic acid, which is a reagent effective for reducing ephedrine or pseudoephedrine to methamphetamine,[11] the United States Drug Enforcement Administration designated hypophosphorous acid (and its salts) as a List I precursor chemical effective November 16, 2001.[12] Accordingly, handlers of hypophosphorous acid or its salts in the United States are subject to stringent regulatory controls including registration, recordkeeping, reporting, and import/export requirements pursuant to the Controlled Substances Act and 21 CFR §§ 1309 and 1310.[12][13][14]
Organophosphinic acids (Phosphinates)
Main article: Phosphinate
Organophosphinic acids have the formula R2PO2H. The two hydrogen atoms directly bound to phosphorus in phosphinic acid are replaced by organic groups. For example, formaldehyde and H3PO2 react to give (HOCH2)2PO2H. Similarly, phosphinic acid adds to Michael acceptors, for example with acrylamide it gives H(HO)P(O)CH2CH2C(O)NH2. The Cyanex family of dialkylphosphinic acids are used in hydrometallurgy to extract metals from ores.
Inorganic derivatives
Few metal complexes have been prepared from H3PO2, one example is Ni(O2PH2)2.Free hypophosphorous acid, H3PO2, is prepared by acidifying aqueous solutions of hypophosphite ions, H2PO2-. For example, the solution remaining when phosphine is prepared from the reaction of white phosphorus and a base contains the H2PO2- ion. If barium hydroxide (BaOH) is used as the base and the solution is acidified with sulfuric acid, barium sulfate, BaSO4, precipitates, and an aqueous solution of hypophosphorous acid results.
Ba2+ + 2H2PO2- + 2H3O+ + SO42- → BaSO4 + 2H3PO2 + 2H2O
The pure acid cannot be isolated merely by evaporating the water, however, because of the easy oxidation of the hypophosphorous acid to phosphoric acids (and elemental phosphorus) and its disproportionation to phosphine and phosphorous acid. The pure acid can be obtained by extraction of its aqueous solution by diethyl ether, (C2H5)2O. Pure hypophosphorous acid forms white crystals that melt at 26.5 °C (79.7 °F). The electronic structure of hypophosphorous acid is such that it has only one hydrogen atom bound to oxygen, and it is thus a monoprotic oxyacid. It is a weak acid and forms only one series of salts, the hypophosphites. Hydrated sodium hypophosphite, NaH2PO2 · H2O, is used as an industrial reducing agent, particularly for the electroless plating of nickel onto metals and nonmetals.
Hypophosphorous Acid Uses
Bleaching Agent
Hypophosphorous Acid is used as a bleaching or decolorizing agent for plastics, synthetic fibers, and chemicals
Color Stabilizer
HPA is used as a decolorizing agent and for color stabilization during the manufacture of chemicals and several plastics including: nylon fibers, polyamides, polyester fiber, polyacrilonitrile, alkyd rsins, epoxies, fatty acid esters, and glycerols.
Hypophosphite Salts
Hypophosphorous Acid is used in the production of Hypophosphite Salts (i.e., Calcium, Magnesium, Manganese, Potassium, Iron, and Ammonium) which are in turn used in synthetic fibers as wetting dispersing, emulsifying, and anti-static agents
Chemical Intermediate
Used in organic synthesis and organo phosphinic acid production
Neturalizing Agent
Used as a moderately strong monobasic acid
Catalyst
Used as a polymerization and polycondensation catalyst
Wetting Agent
Used as a wetting, dispersing, or emulsifying agent in electroplating
Reducing Agent
May be used for its strong but slow reducing action
Antioxidant
Hypophosphorous Acid may be used as an antioxidant
Pharmaceutical
HPA may be used as a stimulant in pharmaceuticals
Hypophosphorous acid Chemical Properties,Uses,Production
Outline
Hypophosphorous acid is also known as “hypophosphite” It is colorless oil or deliquescence crystal , it is an important fine chemical product. The main use is as reducing agent for electroless plating, phosphoric prevent discoloration of resins, it can also be used in the esterification reaction catalyst, the refrigerant, in particular for the production of high purity product sodium hypophosphite. There are several methods for preparation, the common industrial method for producing is ion exchange resin method and electrodialysis method.
The chemical properties of hypophosphorous acid, uses, toxicity, and production methods are edited by andy of Chemicalbook. (2016-12-04)
Chemical properties
It is deliquescent crystals or colorless oil. Melting point: 26.5℃. The relative density (specific gravity): 1.439 (solid, 19℃). It is soluble in water, ethanol and ether, and it can be mixed in any proportion with water, ethanol, acetone. In the air, it easily deliquesce to syrupy liquid, and the aqueous solution is acidic.
Hypophosphorous acid is monobasic acid, in aqueous solution, Hypophosphorous acid is strong acid, Ka = 10-2 (25℃); it is relatively stable at room temperature; disproportionation reaction can proceed at 130℃, decompose into phosphine and phosphorous acid:
2H3PO2=H3PO4+PH3
It has strong reduction, heavy metal salt solution can be restored to metals such as Cu2 +, Hg2 +, Ag +, such as:
4Ag+H3PO2+2H2)=4Ag+H3PO4+4H+
It is weak oxidizer, it can be reduced to phosphine, phosphine when encounters strong reducing agent.
Uses
1. Hypophosphorous acid is used as reducing agent for electroless plating;
2. It can be used to prevent discoloration of phosphoric acid resin;
3. It is used as esterification catalyst, the refrigerant;
4. It is used to produce hypophosphite, sodium salts, manganese salts, iron salts are generally used as nourishing substances;
5. Hypophosphorous acid is used in medicine and as reducing agent, the determination of arsenic, tellurium and separation of tantalum, niobium and other reagents.
6. It is strong reducing agent, It can be used for the preparation of sodium hypophosphite, calcium phosphate and other hypophosphite.
7. It can be used for the plating bath. Pharmaceuticals. reducing agent. general reagents.
8. It is strong reducing agent, it can be used in making sodium hypophosphite, calcium phosphate and other hypophosphite.
9. This product is widely used as reducing agent, Ag, Cu, Ni, Hg and other metals are reduced to the corresponding metal, for the verification of As, Nb, Ta and other reagents, it can be used for the preparation of Na, K, Ca, Mn, Fe and other types of hypophosphite.
Toxicity
It is non-combustible. But when contacts with the hole H agent, it will cause fire. When meets oxidizing agent, violent reaction and combustion can proceed. When it is heated to high, it can decompose into highly toxic phosphine gas, or even explode. It is corrosive. Hypophosphorous acid is often added into soft drinks, and because it is not absorbed. So the risk is small, but particularly strong hypophosphite hurt gastrointestinal. Accidentally it splashes into the eyes or contacts skin, plenty of water is used to washed. Production operators should wear protective clothing and other protective clothing. Production equipment should be sealed, workshop should be ventilated well.
HAZARDS IDENTIFICATION
Hazard statement:
Causes severe skin burns and eye damage.
Causes serious eye damage
Precautionary statements:
Do not breathe dust/fume/gas/mist/vapors/spray.
Wash thoroughly after handling.
Wear protective gloves and eye/face protection.
IF SWALLOWED: Rinse mouth. Do NOT induce vomiting.
IF ON SKIN (or hair): Remove/Take off immediately all contaminated clothing. Rinse skin with water/shower.
IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if
present and easy to do. Continue rinsing.
IF INHALED: Remove victim to fresh air and keep at rest in a position comfortable for breathing.
Immediately call a POISON CENTRE or doctor/physician.
Store locked up.
Dispose of this material and its container to hazardous or special waste collection point.
Preparation method
1. Phosphorus and barium hydroxide solution is heated, barium salt Ba (H2PO2) 2 • 2H2O can generate, sulfuric acid is added into hypophosphorous acid barium solution, Ba2+ can precipitate:
Ba(H2PO2)2+H2SO4=BaSO4+2H3PO2
Hypophosphorous acid can be obtained by evaporating under reduced pressure and low temperature crystallization. Due to in this process, the solubility of the barium salt is small, so the concentration of obtained Hypophosphorous acid is not high, industrial product should be purified by recrystallization.
2. the barium oxide (or lime) and solution of white phosphorus is heated together to form secondary barium phosphate (or calcium), and then reacts with sulfuric acid, it is filtered, concentrated to obtain product, or sodium hypophosphite solution proceeds H-type ion exchange resin can derive product. This method requires a large amount of resin, and resin regeneration and washing step is cumbersome, it generally costs more than $ 7 per pound, it is only suitable for small batch production, and not suitable for large-scale industrial applications.
3. Hypophosphorous acid is prepared by electrodialysis method, wherein the electrodialysis cell divides into three parts, they are anode chamber, raw material chamber and cathode chamber, the intermediate is separated by anionic membrane and cationic membrane, between two membranes sodium hypophosphite solution is placed (concentration of 100g/L~500g/L), anode chamber is dilute solution of Hypophosphorous acid 5g/L, anode chamber is dilute sodium hydroxide solution ( 5g /L), between the poles DC (3V~36V) is passed, anode releases oxygen, and generates secondary product of Hypophosphorous acid; cathode emits hydrogen, and generates secondary product of sodium hydroxide, the reaction time is 3~21h. The reactions of anode chamber and cathode chamber are as follows:
anode chamber:
H2O==H++OH-
2OH-==O2+2H2O+4e
H++H2PO2-==H3PO2
cathode chamber:
H2O==H++OH-
2H++2e==H2
Na++OH-==NaOH
Electrodialysis method of preparation Hypophosphorous acid is simple and equipment investment is small, it is suitable for mass production.
4. Starting from the industrial grade sodium hypophosphite, Cl-, SO42-anions which affect the quality indicators of Hypophosphorous acid are removed by precipitation, heavy metal ions are removed from the solution by forming sulfide, and then using strong acid cation exchange resin to obtain sodium secondary phosphate, high purity grade product can obtain. The process can produce high-grade secondary phosphate, technically is feasible, the process is simple, easy operation, good product quality, it can meet the needs of the electronics industry, defense industry and other high-tech fields.
Production Process of Hypophosphorous Acid from Industrial Sodium Hypophosphite
figure 1 Production Process of Hypophosphorous Acid from Industrial Sodium Hypophosphite.
5. Ion exchange resin method: about 70g of cation exchange resin wetted with water is packed into a glass tube with 5 mol/L hydrochloric acid circulating about 15min, after thoroughly washed with water, high purity aqueous sodium hypophosphite aqueous solution (15 g/60 ml H2O) flows through it, the resin column is first washed with 50 ml, then with 25 rnl distilled water. The effluent acid and washing is combined, it is concentrated by evaporation in water bath. The concentrated acid is placed in high vacuum with P205 dryer for dehydration, cooling and crystallization, filtration, recrystallization, to obtain hypophosphorous acid product.
Production method
Ion exchange resin method: put about 70 g water-soluble cation exchange resins to fill into a glass tube. Circulate with 5 mol/L hydrochloric acid for about 15 min and wash sufficiently with water. Have a high aqueous sodium hypophosphite solution (15 g/60 ml H2O) to flow through the resin column, followed by being washed first with 50 ml water, and then rinsing with 25 rnl distilled water. The effluent acid and the washings were combined and concentrated by evaporation on a water bath. The concentrated acid is send to the highly vacuum, P205 dryer for dehydration, followed by cooling crystallization, filtration and recrystallization to obtain the finished product of hypophosphorous acid.
Description
Hypophosphorous acid is a powerful reducing agent with a molecular formula of H3PO2. Inorganic chemists refer to the free acid by this name although its IUPAC name is dihydridohydroxidooxidophosphorus, or the acceptable name of phosphinic acid. It is a colorless low-melting compound, which is soluble in water, dioxane, and alcohols. The formula for hypophosphorous acid is generally written H3PO2, but a more descriptive presentation is HOP(O)H2 which highlights its monoprotic character. Salts derived from this acid are called phosphinates (hypophosphites).
Description
This acid has the general formula ofH4P2O6 and differs from the other oxy-phosphorous acids. It has many peculiarities. It is formed along with phosphorous and phosphoric acids, when phosphorus is oxidized by moist air. If white phosphorus is exposed to air, and sodium acetate is addedto the liquidwhich forms, the somewhat insoluble sodium hypophosphate,Na2H2P2O6·6H2Oseparates. The sodium hypophosphate monohydrate, however, is very soluble and deliquescent at ～98.7 g/100 ml.
Chemical Properties
colourless liquid
Uses
Preparation of hypophosphites, electroplating baths.
Definition
ChEBI: A phosphorus oxoacid that consists of a single pentavalent phosphorus covalently bound via single bonds to two hydrogens and a hydroxy group and via a double bond to an oxygen. The parent of the class of phosphinic acids.
Definition
A white crystalline solid. It is a monobasic acid forming the anion H2PO2 – in water. The sodium salt, and hence the acid, can be prepared by heating yellow phosphorus with sodium hydroxide solution. The free acid and its salts are powerful reducing agents.
General Description
Colorless oily liquid or deliquescent crystals with a sour odor. Density 1.439 g / cm3. Melting point 26.5°C. Inhalation of vapors irritates or burns the respiratory tract. Liquid and vapors may irritate or burn eyes and skin.
Air & Water Reactions
Deliquescent. Water soluble.
Reactivity Profile
HYPOPHOSPHOROUS ACID decomposes when heated into phosphoric acid and spontaneously flammable phosphine. Is oxidized by sulfuric acid with release of sulfur dioxide and sulfur. Reacts explosively with mercury(II) oxide [Mellor, 1940, Vol. 4, 778]. Reacts violently with mercury(II) nitrate [Mellor, 1940, Vol. 4, 993]. Neutralizes bases in exothermic reactions.
Hazard
Fire and explosion risk in contact with oxidizing agents.
Health Hazard
TOXIC; inhalation, ingestion or skin contact with material may cause severe injury or death. Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution.
Fire Hazard
Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated.
Purification Methods
Phosphorous acid is a common contaminant of commercial 50% hypophosphorous acid. Jenkins and Jones [J Am Chem Soc 74 1353 1952] purified this material by evaporating about 600mL in a 1L flask at 40o, under reduced pressure (in N2), to a volume of about 300mL. After the solution was cooled, it was transferred to a wide-mouthed Erlenmeyer flask which was stoppered and left in a Dry-ice/acetone bath for several hours to freeze (if necessary, with scratching of the wall). When the flask was then left at ca 5o for 12hours, about 30-40% of it liquefied, and was again filtered. This process was repeated, then the solid was stored over Mg(ClO4)2 in a vacuum desiccator in the cold. Subsequent crystallisations from n-butanol by dissolving it at room temperature and then cooling in an ice-salt bath at -20o did not appear to purify it further. The free acid forms deliquescent crystals m 26.5o and is soluble in H2O and EtOH. The NaH2PO2 salt can be purified through an anion exchange resin [Klement Z Anorg Allgem Chem 260 267 1949.]
Hypophosphorus acid is a colorless, oily liquid or absorbant crystals. Hypophosphorus acid mixes easily with water. It is a US Drug Enforcement Administration (DEA) Schedule I Controlled Substance. USE: Hypophosphorus acid is used as a bleaching agent, in electroplating baths and to make other chemicals, including the illicit drug methamphetamine. EXPOSURE: Workers that use hypophosphorus acid may breathe in vapors or have direct skin contact. The general population is not likely to be exposed to hypophosphorus acid. Limited exposure will occur to those using hypophosphorus acid when manufacturing illegal drugs. If hypophosphorus acid is released to the environment, it is uncertain if the vapors will or will not be broken down in air. It is not known if it will be broken down by sunlight. It will not move into air from moist soil and water surfaces. It is expected to move quickly through soil. It is not expected to build up in fish. RISK: Hypophosphorus acid is corrosive to human skin in concentrated and dilute solutions. Additional data on the potential for hypophosphorus acid to produce toxic effects in humans were not available. Data on the potential for hypophosphorus acid to produce toxic effects in animals were not available. Data on the potential for hypophosphorus acid to cause cancer, birth defects or reproductive effects in laboratory animals were not available. The potential for hypophosphorus acid to cause cancer in humans has not been assessed by the U.S. EPA IRIS program, the International Agency for Research on Cancer, or the U.S. National Toxicology Program 14th Report on Carcinogens. Based on a classification scheme(1), a measured Koc range of 3.7 to 15 for the analogous sodium hypophosphite (which dissociates into the hypophosphorus acid ion in water)(2) indicates that hypophosphorus acid is not expected to adsorb to suspended solids and sediment(SRC). The pKa of hypophosphorous acid is 2.27(3), indicating that this compound will exist almost entirely in ionized form in the environment(SRC). Since ionized forms do not volatilize, volatilization from water surfaces is not expected to be an important fate process(SRC). According to a classification scheme(4), an estimated BCF of 3(SRC), from an estimated log Kow of -1.72(5) and a regression-derived equation(5), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Biodegradation data in water were not available(SRC, 2017). Based on hydrolysis results for sodium hypophosphite(2), hypophosphorus acid is stable to hydrolysis in water.According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), hypophosphorus acid, which has a vapor pressure of 0.00323 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase hypophosphorus acid may be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); however, the half-life for this reaction in air can not be estimated appropriately with current estimation methods since hypophosphorus acid in an inorganic compound(3). Hypophosphorus acid is miscible in water(4), therefore, atmospheric hypophosphorus acid may dissolve in precipitation, cloud or fog water and be removed from air via wet deposition(SRC).Sodium hypophosphite dissociates into hypophosphorus acid ions in water(1). Using OECD Guideline 111 (Hydrolysis as a Function of pH), sodium hypophosphite showed very minor hydrolytic degradation at pH values of 4.0, 7.0 and 9.0 and 50 °C(1). The estimated hydrolysis half-life is greater than one year under representative environmental conditions at 25 °C; therefore, sodium hypophosphite is considered to be hydrolytically stable(1). This should also apply to hypophosphorus acid.Using OECD Guideline 106 (Adsorption – Desorption Using a Batch Equilibrium Method) and five different soil types, sodium hypophosphite had Koc values ranging from 3.7 to 15(1). Since sodium hypophosphite dissociates into hypophosphorus acid ions in water(1), the Koc results will also apply to hypophosphorus acid(2). According to a classification scheme(3), these Koc values suggests that hypophosphorous acid is expected to have very high mobility in soil.Hypophosphorous acid is used in preparation of hypophosphites, and in electroplating baths. HUMAN STUDIES: Hypophosphorous acid solution (50%) was corrosive in a standardized and quantitative in vitro corrosivity test.Hypophosphorus acid’s production and use in electroplating baths, in the preparation of hypophosphites and as a bleaching agent, reducing agent and catalyst may result in its release to the environment through various waste streams. If released to air, a vapor pressure of 0.00323 mm Hg at 25 deg C indicates hypophosphorus acid will exist solely as a vapor in the atmosphere. Vapor-phase hypophosphorus acid will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air can not be estimated appropriately with current estimation methods. Hypophosphorus acid is miscible in water, and therefore, may dissolve in precipitation, cloud or fog water and be removed from air via wet deposition. If released to soil, hypophosphorus acid is expected to have very high mobility based upon a measured Koc range of 3.7 to 15 for the analogous sodium hypochorite. The pKa of hypophosphorous acid is 2.27, indicating that this compound will exist almost entirely in ionized form in the environment. Since ionized forms do not volatilize, volatilization from moist soil is not expected to be an important fate process. Hypophosphorus acid is not expected to volatilize from dry soil surfaces based upon its vapor pressure. If released into water, hypophosphorus acid is not expected to adsorb to suspended solids and sediment based upon the Koc. Biodegradation data in water or soil were not available. Volatilization from water surfaces is not expected to be an important fate process since the compound ionizes in water. An estimated BCF of 3 suggests the potential for bioconcentration in aquatic organisms is low. Based on hydrolysis results for sodium hypophosphite, hypophosphorus acid is stable to hydrolysis in water. Occupational exposure to hypophosphorous acid may occur through inhalation and dermal contact with this compound at workplaces where hypophosphorous acid is produced or used. Exposure to the general population may be possible in the vicinity of its use as a reagent during illicit drug manufacture. Hypophosphorous acid is on the US DEA (Drug Enforcement Administration) list of special surveillance chemicals used in clandestine drug manufacture.