| 摘要 |
Novel magnesiosilicate compounds for use in detergent compositions and as water softeners have a calcium binding capacity of at least 10 mg CaO per gram, a magnesium binding capacity of at least 10 mg MgO per gram and a calcium binding rate of no more than 300 seconds, all at room temperature. The compounds have a stuffed silica polymorph-related structure or a layered structure with a broad X-ray powder diffraction peak at a d-spacing of between 11 and 17 .ANG.. The compounds have an anhydrous composition MaMgbAlcSi1 (b+c)Od, where M = alkali, 0.0 < a < 2.0, 0.0 < b < 0.7, 0.0 c 0.3, 1.15 < d < 3.0, c < b, and partial substitution of M, Mg, Al and Si is permitted. The compounds are prepared by solid state reaction or aqueous reaction of starting material such as magnesiosilicate mineral with alkali oxide-containing reagent under relatively mild conditions or by treating a magnesiosilicate compound having a stuffed silica polymorph-related structure with aqueous solution.
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