Zeolite p aluminosilicates and their manufacture and use in detergent compositions

Abstract

P-type zeolite having the oxide formula M2 / n, Al2O3, (1.8-2.66) SiO2, y H2O and having a Calcium Binding Capacity of between 100 and 145 mg / g, preferably between 110 and 140 and a Calcium uptake rate of between 12 and 100 seconds, preferably below 50 seconds can be prepared from metakaolin.

Description

[0001] The invention relates to crystalline aluminosilicates having the P-structure and to a process for manufacturing the same. These materials are of value as a component in detergent formulations in which they remove calcium and magnesium hardness ions by ion exchange. They also have other properties which provide additional benefits when used in detergent formulations. These aluminosilicates will be referred to as zeolite P in this description.[0002] While the utility of zeolite P in detergent formulations has been acknowledged, for example in European Patent Application 0384070 (Unilever), they must be manufactured by a commercially effective process in order to become available on the market place. Thus, while the properties of a material may make it a useful commercial commodity, its manufacture has to be optimised for large scale production.[0003] The zeolite P class includes a series of synthetic zeolite phases which may be in cubic configuration (also termed B or P.sub.c) ...

AI Technical Summary

Problems solved by technology

Moreover, the kinetics characteristics of these zeolites were found to be very poor with a Calcium Uptake Rate of above 500 seconds.

Therefore the zeolites P disclosed in U.S. Pat. No. 3,112,176 and U.S. Pat. No. 3,008,803 are not suitable for detergent applications.

For the time being, it has not been possible to obtain such a P-type zeolite.

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