Tetrasodium pyrophosphate anhydrous

TETRASODIUM DIPHOSPHATE TETRASODIUM PYROPHOSPHATE, ANHYDROUS TSPP VICTOR TSPP... 

ETHYLENEDINITRILO)TETRAACETATE see ERWO TETRASODIUM PYROPHOSPHATE see TEE500 TETRASODIUM PYROPHOSPHATE, ANHYDROUS see TEE500... 

Synonyms/Trade Names Pyrophosphate, Sodium pyrophosphate, Tetrasodium diphosphate, Tetrasodium pyrophosphate (anhydrous), TSPP ... 

Crystalline CaHPO 2H20 loses both water molecules in a single step at moderately elevated temperature or upon storage to yield the anhydrous salt. The presence of free moisture accelerates this dehydration, which results in anhydrous dicalcium phosphate, often as a hard mass. Addition of a few percent of tetrasodium pyrophosphate or trimagnesium phosphate, Mg2(P0 2> stabilizes the dihydrate. The mechanism, however, is not well understood. Nonetheless, these materials are used widely to stabilize CaHPO 2H20, particulady for toothpaste appHcations. 

TSPP is readily crystallised from water as the decahydrate between —0.4° and 79°C, and as the anhydrous salt above 79°C. The solubiUty of tetrasodium pyrophosphate is illustrated in Figure 8. The pH of a 1% solution is 10.2. TSPP is quite stable in alkaline medium but hydrolyses rapidly to orthophosphate under acid conditions. 

Sodium tripolyphosphate is produced by calcination of an intimate mixture of orthophosphate salts containing the correct overall Na/P mole ratio of 1.67. The proportions of the two anhydrous STP phases are controlled by the calcination conditions. Commercial STP typically contain a few percent of tetrasodium pyrophosphate and some trimetaphosphate. A small amount of unconverted orthophosphates and long-chain polyphosphates also may be present. 

G. Merling 4 found dihydrated tetralithium pyrophosphate loses 7 03 per cent, of water at 100°, and 14 55 per cent, when melted, and C. F. Rammelsberg adds that the whole of the combined water is lost when the salt melts at 200°. T. Camelley gives the melting point of anhydrous tetrasodium pyrophosphate as about 880°, and... 

H. le Chatelier gives 940°. The latter also measured the m.p. of mixtures of this compound with anhydrous borax (melting at 970°), and found a maximum in the curve at 960° and 58 3 per cent, of tetrasodium pyrophosphate corresponding with the compound Na4P207.3Na2B407, with eutectics at 910° and 850° corresponding respectively with 16 7 and 83 7 per cent, of the pyrophosphate. According to... 

Spray a mixture of the Macol 40 and water onto the Tetrasodium Pyrophosphate (alone or mixed with the other anhydrous inorganic salts) while continually mixing, whereby hydration and simultaneous absorption of the surfactant occur. 

Sodium Metasilicate (Anhydrous) Tetrasodium Pyrophosphate (Powder) Butyl Carbitol Mona NF-10... 

Fused tetrasodium pyrophosphate is a white crystalline mass the decahydrate forms monoclinic ctSTStsds, which were measured by C.F. Rammelsberg,W. Haidinger, A. Handl, A. Scacchi, and H. Dufet.3 The axial ratios are o c=l 2873 1 1 8951, and 16. The specific gravity of anhydrous tetrasodium pyrophosphate is... 

Anhydrous tetrasodium pyrophosphate Caswell No. 847 Diphosphoric acid, tetrasodium salt EINECS 231-767-1 EPA Pesticide Chemical Code 0764()5 HSDB 854 Natrium pyrophosphat NSC 56751 Phosphotex Pyrophosphoric acid, tetrasodium salt Sodium diphosphate (Na4P20 ) Sodium diphosphate, anhydrous Sodium phosphate (Na4P207) Sodium pyrophosphate Sodium pyrophosphate, tetrabasic ... 

Since these products are often manually handled during, for instance, swimming pool cleaning and maintenance, they must be converted into shapes with properties that avoid nuisance dust and enhance stability. The pure chemicals, which, as produced, may be very fine (e.g., sometimes precipitated), are often mixed with other components for specific performance. For example, Oxone can be blended with many additives, including sodium-sulfate, -carbonate (especially the dense version), -bicarbonate, -perborate, -tripolyphosphate, -metasUicate, tetrasodium pyrophosphate, citric-, malic-, and tartaric-acids and surfactants and fragrances. To maintain stability, all ingredients must be anhydrous or hold hydrated water tightly. 

Ingredient Wt. % Sodium Metasilicate, anhydrous 35.00 Tetrasodium Pyrophosphate (1) 20.00 Sodium Tripolyphosphate (2) 5.00 Bentonite Clay 8.00 Sodium Percarbonate 15.00 Triton QS-44 (3) 7.00 Sodium Sulfate 10.00... 

Sodium PCA Sodium p-styrenesulfonate Sodium thiocyanate Sulfated castor oil Tallowalkonium chloride Tallowtrimonium chloride Tetrasodium pyrophosphate 1,3,5-Trihydroxybenzene Vanadium pentoxide dyeing assistant, wool Fluorescein Maleic acid dyeing assistant, wool fiber processing PEG-25 tallowamine dyeing auxiliary, textiles Magnesium sulfate anhydrous dyeing fabrics Sodium chloride dyeing fur... 

To 100 ml. of a saturated aqueous solution of tetrasodium pyrophosphate at 40° there is added 75 ml. of glacial acetic acid. After the acetic acid has been added, the temperature is brought back up to 40° and the solution agitated until crystallization is complete (approx. 2 to 3 hours). Crystals will appear in 30 to 60 minutes and grow slowly. When crystallization has proceeded for about 30 minutes, the temperature may be dropped slowly to 30°, but not less. The crystals are filtered off using vacuum, washed with two portions of ice water, and dried at 100°. This procedure yields about 6 g. of anhydrous crystals which, if grown slowly enough, are of sufficient size for study under a microscope. 

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