Phosphates, in detergents

Question 5.12 Why Does Soap Scum Form Why Are Phosphates in Detergents 53... 

Nonlinear, nonbiodegradable synthetic detergents made from propylene tetramer were banned after these materials were found in large amounts in rivers, so much as to cause soapy foam in many locations. Phosphates in detergents were banned in detergents by many states in the 1970s. 

A number of critical water problems face us today. We have already discussed information relating to areas of the chemical industry specifically, such as phosphate in detergents and nonbiodegradable detergents. Certainly efforts by general industry must be continued to eliminate local contamination that may occur, whether it be from oil spills or the typical manufacturing plant down the street. 

A builder is a compound that removes calcium and magnesium ions normally present in water, and, as a result, reduces the concentration of surfactants required to carry out the detergent action. Currently, the builder mainly used in practice is sodium tripolyphosphate. However, phosphates are plant nutrients and provoke eutrophication in lakes and streams which receive municipal wastewater contaminated with detergent residuals. Consequently, the use of phosphates in detergents has been restricted. 

Citric acid is used in soft drinks, candies, wines, desserts, jellies, jams, as an antioxidant in frozen fruits and vegetables, and as an emulsifier in cheese. As the most versatile food acidulant, citric acid accounts for about 70 percent of the total food acidulant market. It provides effervescence by combining the citric acid with a biocarbonate/carbonate source to form carbon dioxide. Citric acid and its salts are also used in blood anticoagulants to chelate calcium, block blood clotting, and buffer the blood. Citric acid is contained in various cosmetic products such as hair shampoos, rinses, lotions, creams, and toothpastes. More recently, citric acid has been used for metal cleaning, substituted for phosphate in detergents, for secondary oil recovery, and as a buffer/absorber in stack gas desulfurization. The use of sodium citrate in heavy-duty liquid laundry detergent formulations has resulted in a rapid increase in the use of citric acid. 

Phosphates in Detergents and the Eutrophication of America s Waters", 23rd Report, Comm, on Govt. Operations, US Printing Office, Washington, p. 27 (1970). 

Fig. 8-52. Analysis of condensed phosphates in detergents. - Separator column IonPac AS7 eluent 0.07 mol/L HN03 flow rate 0.5 mL/min detection photometry at 330 nm after reaction with ferric nitrate injection 50 pL of a 0.1% washing powder solution.

Sodium perborate Milder bleach for laundering dry cleaning denture cleaning tooth powder replacement for phosphates in detergents... 

Although these functions were recognized in the earlier literature, their relative importance has been affected by several recent developments. These include legislative restrictions on the amount or presence of phosphates in detergents and the use of alternate organic and inorganic builders as a consequence. 

The double bond of 4,7-dihydro-1,3-dioxepins has been cleaved by permanganate oxidation in aqueous potassium hydroxide solution at 0°C to give the potassium bis(carboxymethyl) acetals (98), which can be used as substitutes for phosphate in detergent formulation <81S612>. 

Phosphoric acid and its salts find their most important uses in detergents and fertilizers. The phosphates in detergents are often in the form of sodium tripolyphosphate... 

Uses Pigment dispersant for clays, paints, adhesives, paper, and latexes replaces phosphates in detergents Properties Low m.w. anionic Dumasperse 543 [Hi-Mar Spec. Thornley]... 

Uses Used in formulations that are replacements for phosphates in detergents Gluconolactone... 

Typical examples of analytical applications of conventional MECA include the determination of saccharin (sulfur-containing sweetener) in soft drinks, total sulfur and sulfate in detergents, phosphate in detergents and rocks, sulfur dioxide in air, inorganic sulfate in urine, and halides in pesticides. 

P.A. Gilbert and A.L. Dejong, The use of phosphate in detergents, in Phosphorus and the Environment, Ciba Foundation Symp. No. 57, Elsevier, Amsterdam, 1978. 

Sodium metasilicate - me-t9- si-b- kat (ca. 1926) n. Na2Si03. A toxic corrosive crystal-fine salt used mostly as a detergent or as a substitute for phosphates in detergent formulations. 

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