Sodium tripolyphosphate polyphosphates

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. 

Sequestration forms the basis for detergent and water-treatment appHcations of polyphosphates. Sequestration of hardness ions by sodium tripolyphosphate used in detergent formulations prevents the precipitation of surfactants by the hardness ions. Sodium polyphosphate glass (SHMP) may be added to water system to prevent the formation of calcium or magnesium scales by reducing the activity of the hardness ions. However, if the ratio of cation to polyphosphate is too high at a given pH, insoluble precipitates such as may result instead of the soluble polyphosphate complexes. The... 

Figure 10.1 Types of phosphate structures, (a) Where x = 12 to 14, the structure represents sodium polyphosphate, a phosphate typically used in HW heating and industrial steam boiler formulations. The structure is ill defined and described as glassy rather than crystalline. Where x = 2, it represents sodium tripolyphosphate, (b) This is the structure where effectively, x = 0, and represents trisodium phosphate (sodium orthophosphate), which is commonly supplied in either crystalline or anhydrous powder form and used as an alkalinity booster, boiler boil-out cleaner, and metal surfaces passivator.

Chang (1976) showed that use of a polyphosphate, which is a buffer, improved recovery. Sodium tripolyphosphate (STPP) was used in laboratory tests for Cretaceous Upper Edwards reservoir (Central Texas). STPP was proposed to minimize divalent precipitation, for wettability alteration and emulsification (Olsen et al., 1990). Generally, it is not used as a primary alkali to generate soap for purposes of IFT reduction. Instead, it is used together with other alkalis such as sodium carbonate when divalents could be a problem (Harry Chang, Chemor Tech International, Plano, Texas, personal communication on June 16, 2009). 

The salts of the above acids are known as polyphosphates and are used extensively in industry (including water treatment), predominantly due to their strong metal ion complexing abilities (sequestering agents). A common example is sodium tripolyphosphate (STPP) or Na5P30io, which is used extensively as a builder for household detergents. 

Sodium hexametaphosphate is one of a series of chain polymers termed polyphosphates, and threshold treatment using various members of the series has found extensive use in controlling calcium carbonate scale formation. Veale [1984] states that typically 5 mg/l of polyphosphate will inhibit the precipitation of 500 mg/l of CaCOy To control scale in sea water evaporation an additive mixture could include sodium tripolyphosphate, lignin sulphonates and an antifoaming agent. 

The hydrolysis of condensed phosphates during the orthophosphate analysis was virtually eliminated by minimizing contact time between the acidic reagents and the sample. Negative results were obtained when concentrated solutions of sodium tripolyphosphate were analyzed by this technique, however in the reactive phosphate technique of Strickland and Parsons (20)—a widely used oceanographic method—considerable hydrolysis of the polyphosphate took place. 

Potassium dihydrogen citrate Potassium fumarate Potassium hydrogen malate Potassium hydroxide Potassium lactate Potassium malate Potassium phosphate Potassium phosphate dibasic Potassium phosphate tribasic Potassium polyphosphate Potassium sodium tartrate Potassium sodium tartrate tetrahydrate Potassium tripolyphosphate Sodium acetate anhydrous Sodium acetate trihydrate Sodium acid pyrophosphate Sodium aluminum phosphate acidic Sodium aluminum phosphate basic Sodium bicarbonate Sodium calcium polyphosphate Sodium carbonate Sodium citrate Sodium diacetate . Sodium fumarate Sodium hydrogen malate... 

Potassium sodium tartrate tetrahydrate Potassium tripolyphosphate Sodium acetate anhydrous Sodium acid pyrophosphate Sodium calcium polyphosphate Sodium carbonate Sodium citrate Sodium diacetate Sodium gluconate Sodium hexametaphosphate... 

Elucidation of photosynthesis cycle commenced Showed enzymes accelerated hydrolysis of inorganic polyphosphates Electroless plating principle utilising hypophosphite estabUshed USA - Introduction of commercial detergent powders containing sodium tripolyphosphate Isolated co-enzyme A... 

Polyphosphates, e.g., sodium pyrophosphate (Na4P20v), sodium tripolyphosphate (NasPsOio), and sodium hexametaphosphate ((NaP03)6) that in the presence of divalent metal ions form a protective coating on the metal surface. 

S0% sodium tripolyphosphate and sodium letra-polyphosphate solution (hydrator) Chemical F 165 2.5 XX XX 0.0001 0.0004 ... 

Figure 9.24(a) Apparent viscosity, zeta potential, amount of adsorption, and pH in zinc oxide-water (50/50) suspensions versus initial concentration, c, curves for Na salt of polyacrylic acid (PA) (O), Na salt of formalin condensate of -naphthalene sulphonate acid (NSF) (C), and sodium tripolyphosphate ( ). The initial concentrations of PA and NSF refer to the mole concentrations expressed/monomer unit of them. A dotted line refers to the apparent viscosity versus c curve for PA at a controlled pH of 10.1. C = initial mole concentration of surfactant and polyphosphate, (b) Apparent viscosity, zeta potential, amount of adsorption, and pH in zinc oxide-water (50/50) suspensions versus initial concentration, c, curves for Na salt of formalin condensate of alkyl (C4) naphthalene sulphonic acid (Al-NSF) (Ci), sodium alkyl (C4) naphthalene sulphonate ( >), and sodium dodecyl benzene sulphonate (O). The initial concentrations of Al-NSF refer to the mole concentrations expressed/monomer unit. C = initial mole concentration of surfactant. From [61] with permission. 

Various polyphosphates are effective sequestering agents under appropriate conditions. The best known of these is sodium hexametaphosphate (10.14), the cyclic hexamer of sodium orthophosphate. Further examples are the cyclic trimer sodium trimetaphosphate (10.15), as well as the dimeric pyrophosphate (10.16), the trimeric tripolyphosphate (10.17) and other linear polyphosphates (10.18). All of these polyanions function by withdrawing the troublesome metal cation into an innocuous and water-soluble complex anion by a process of ion exchange as shown in Scheme 10.7 for sodium hexametaphosphate. Hence these compounds are sometimes referred to as ion-exchange agents. 

Sodium Metaphosphate, Insoluble, 52 Sodium Phosphate, Dibasic, 53 Sodium Phosphate, Monobasic, 54 Sodium Phosphate, Tribasic, 54 Sodium Polyphosphates, Glassy, 55 Sodium Potassium Tripolyphosphate, 56... 

Kalipol 20. See Sodium hexametaphosphate Kalipol 32. See Sodium phosphate Kalipol 36AZ. See Ammonium polyphosphate Kalipol KTP. See Potassium tripolyphosphate Kama CS Kama OPS. See Polystyrene Kamamine T2802D. See Dimethyl behenamine Kamamine T9902D. See Dimethyl stearamine Kamax T-150 Kamax T-17(7, Kamax T-240 Kamax T-242 Kamax T-260. See Acrylic-imide copolymer... 

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