Chlorinated trisodium orthophosphate

Chlorinated Trisodium Phosphate. Chlorinated trisodium phosphate [11084-85-8] is a crystalline complex of hydrated trisodium orthophosphate and sodium hypochlorite that releases hypochlorite when mixed with water. Its formula is (Na PO 11H20)4 NaOCl. Commercial... 

According to Bell (3), Cl-TSP has the empirical formula 4(Na3P04-XH20) NaY, where X=ll-12 and Y is OCl. This empirical formula, however, is not in agreement with the composition given by Mathias (4) and Alder (5). The earlier inventors showed that Cl-TSP has a Na/P mole ratio to be less than three. The Bell proposed formula has been well accepted and a term, chlorinated trisodium phosphate has often been used, as depicted by reaction 1 below. Unfortunately, the implied chemical reaction, chlorination of crystalline trisodium orthophosphate, does not produce the desired product, Cl-TSP. Some clarification of this preparation is needed. 

This chapter reviews the production of sodium, potassium, calcium, and lithium salts of hypochlorite as well as a crystalline complex of hydrated trisodium orthophosphate and sodium hypochlorite known as chlorinated trisodium phosphate. These inorganic hypochlorite salts are used in detergent and cleaning products to kill all types of pathogens, decolorize stains, and break down and remove many kinds of soil. They are also widely used for water and wastewater disinfection and a variety of industrial uses. 

Chlorinated trisodium phosphate was introduced in 1928, about the same time as calcium hypochlorite. It is a crystalline complex of hydrated trisodium orthophosphate and sodium hypochlorite with an approximate formula of (Na3P04 11H20)4 NaOCl. It also contains other phosphate salts and sodium chloride. Chlorinated trisodium phosphate is still used in commercial laundries and disinfectant cleaners. In other products, such as powdered abrasive cleansers and automatic dishwash detergents, it has been largely replaced by chlorinated isocyanurates to reduce cost, improve performance, or comply with phosphate restrictions. 

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