摘要 |
<p>Novel synthetic zeolite pigments are prepared by a process which comprises: (a) heating a mixture comprising crystalline aluminosilicate zeolite (especially type A, X or Y zeolite) and sources of each of sulphur, cations and optionally a reducing agent (e.g. a carbon source), under non-oxidising conditions at a temperature of preferably from 300 to 600 DEG C; (b) contacting the product of step (a) with an oxidising agent, e.g. oxygen or air, in the presence of a solvent or carrier, e.g. water, at a temperature of up to 300 DEG C, preferably up to 150 DEG C; and (c) recovering therefrom a synthetic inorganic zeolite pigment. The pigments recovered are characterized by chemical composition and unique x-ray powder diffraction patterns and exhibit useful properties including adsorption of foreign molecules, ion exchange and characteristic colours.</p> |