Builders, detergent phosphates

Production of Detergent Builders Phosphates, Carbonates, and Polycarboxylates... 

Starch monophosphates are quite useful in foods because of their superior freeze—thaw stabiUty. As thickeners in frozen gravy and frozen cream pie preparations, they are preferred to other starches. A pregelatinized starch phosphate has been developed (131) which is dispersible in cold water, for use in instant dessert powders and icings and nonfood uses such as core binders for metal molds, in papermaking to improve fold strength and surface characteristics, as a textile size, in aluminum refining, and as a detergent builder. 

Ecological Effects of Non-Phosphate Detergent Builders-Final Report on Organic Builders Other than NTA, International Joint Commission, Windsor, Ontario, Canada, July 21, 1980. 

A mathematical model was developed for the purpose of predicting the fate and transport of down-the-drain household chemicals in septic systems. Model simulations were in good agreement with field data for the laundry detergent builders tartrate monosuccinate (TMS) and tartrate dissuccinate (TDS). The model was also independently verified with phosphate data collected from the study site. Results from this study support that this model is satisfactory as a screening level tool for predicting the fate and transport of household chemicals in septic systems. 

Alternatively, finely powdered zeolites may be used in detergent powders as a builder since zeolite particles smaller than 10 pm do not stick to clothing. Formerly, sodium polyphosphates (Section 7.7) were used extensively as detergent builders to tie up the Ca2+ and Mg2+ in hard water as soluble complexes (or as a precipitate that washes away). However, many communities ban phosphate detergents because of pollution problems (Sections 7.7 and 9.6), thus creating a major new market for zeolites. 

Most of the world production of phosphates goes into fertilizer, but some is used as detergent builders (Section 7.7). In toothpastes, calcium pyrophosphate has proved effective as a mild abrasive in eliminating tartar, while Na2[FP03], made by reaction of NaF with cyclic sodium metaphosphates (NaP03), is widely used as a fluoridating agent to suppress dental caries (Section 12.3). A minor amount of rock phosphate is used to make elemental phosphorus by reduction with coke in the presence of silica in the electric furnace (see Section 17.7) ... 

STEROX DJ surfactant is an all-purpose surfactant with a generally lower degree of foaming compared to other alkylphenol-based nonionics. It is an extremely effective detergent at temperatures below 38C (100F) and can be compounded with phosphates and the usual detergent builders for a wide range of applications. 

The International Joint Commission (U.S.-Canada) under the Great Lakes Water Quality Agreement undertook a safety review of detergent builders which encompassed both human health and environmental aspects. The Task Force on the Health Effects of Non-NTA Detergent Builders of the IJC s Great Lakes Science Advisory Board concluded that "the use of sodium silicate in detergents poses no hazard to man" ( ). A separate Task Force on the Ecological Effects of Phosphate Replacements has not yet issued a report, but it is understood to have concluded that there is no cause for concern ( 5). 

Chitin/calcium phosphate complexes can form the basis of artificial bone and dental materials [40] and phosphated chitosan derivatives have been patented as detergent builders [41]. A protonconducting biopolymer has been obtained from chitin phosphate and imidazole [42]. 

Phosphates are considered to be the most cost-effective detergent builder available, combining the properties of high efficacy (calcium sequestration, antiredeposition, buffering of pH), low toxicity, and relatively low cost. Phosphates are compatible with a wide variety of processing methods and product forms, which allows their use in powders, liquids, and bars. Although sodium tripolyphosphate (STPP) is the most common phosphate builder, sodium pyrophosphate is also used in some countries. In Asia, Latin America, and Africa, phosphates are the predominant detergent builders used. 

Two forms of sodinm phosphates have been nsed as detergent builders sodium tripolyphosphate (STPP), which is the more commonly nsed form, and tetrasodium pyrophosphate (TSPP). 

Bauer, H., Schimmel, G., Jtirges, P. 1999. The Evolution of Detergent Builders from Phosphates to Zeolites to Silicates. Tenside Surf. Det. 36 225-229. 

FIGURE 3.13 The nitrilotriacetate anion binding in four places to the Zn metal ion sodium nitrilotriac-etate was once strongly advocated as a substitute for phosphates in household detergent builders, but was not used in the United States because of concern over its tendency to bind with and transport toxic heavy metal ions. (From Manahan, S.E., Environmental Chemistry, Taylor Francis/CRC Press, Boca Raton, FL, 2009. With permission.)... 

Give a reason that Na3P04 would not function well as a detergent builder, whereas NajPjOjo is satisfactory, though it is a source of pollutant phosphate. 

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