Builders, detergent zeolites

A great deal is known about ion exchange in zeolites, because of their importance as detergent builders - Zeolite A is the most widely used. Most of the cation sites in zeolite A are accessible in or from the large a-cages (Figure 6.7)... 

Zeolite A is by far the most widely produced synthetic zeolite, with an annual production of some 1.3 million tonnes. As may be expected from this large volume its main use is not as a catalyst but as a detergent builder (Box 4.2). Since about 1970 the use of zeolite catalysts has provided huge economic and environmental benefits to the bulk chemical and petroleum refining industries. 

Volume 46 Zeolites as Catalysts, Sorbents and Detergent Builders. Applications and... 

A. Endoh, K. Nishiyama, K. Tsutsumi, T. Takaishi, Zeolites as Catalysts, Sorbents and Detergent Builders(Stud. Surf. Sci. Catal., 46), Elsevier, Amsterdam, 1989, p.779. 

H.G. Karge and J. Weitkamp (Eds.), Zeolites as Catalysts, Sorbents and Detergent Builders - Applications and Innovations (Proc. Int. Symp. Zeolites, Wtlrzburg, September 4-8, 1989), Elsevier, Amsterdam 1989. 

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. 

Occelli, M. L. Stencel, J. M. In Zeolites as Catalysts, Sorbents, and Detergent Builders Studies in Surface Science and Technology, Vol. 46 Applications and Innovations, proceedings of an international symposium Karge, H. G. Weitkamp, J., Eds. Elsevier, Amsterdam, 1989 p 127. 

Mhller U, Unger K K, Pan D, Mersmann A, Gnllet Y, Rouquerol F and Rouquerol J (1989) In Zeolites as Catalysts, Sorbents and Detergent Builders (H G Karge and J Weitkamp, eds), Elsevier, Amsterdam, p 625... 

J. A. Johnson and A. R. Oroskar, "Sorbex Technology for Industrial Scale Separation," in H. G. Karge and J. Weitkamp, eds., Zeolites as Catalysts. Solents, and Detergent Builders, Elsevier Science Publishers BV, Amsterdam, 1989. 

Zeolite A, the most important phosphate substitute, became the highly demanded builder worldwide. The worldwide production of zeolite A increased in western Europe in the 1990s. Determent builder zeolites represent the largest application field for zeolite. Almost 90 percent of zeolites produced worldwide (or 215,000 tons/year) in 2003 were used for detergents. Meanwhile, production capacities for detergent-grade zeolites have largely surpassed the demand [4]. 

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