COMPOSITE POLYBASIC SALT, PROCESS FOR PRODUCING THE SAME, AND USE

摘要

A composite-metal polybasic salt which has a chemical composition represente d by the following general formula (1) M3+pMgq(OH)y(A)z. nH2O [wherein M3+ represents a trivalent metal; A represents an anion; 3p+2q-y-mz=0 (m is the valence of A), 0.3 <= q / p <= 2.5, 1.5 <= y / ( p + q ) <= 3.0, and 4.0 <= ( p + q ) / z = 20.0; and n is 7 or smaller], has specific X-ray diffraction peaks, and has a degree of orientation I0 of 1.5 or higher. The composite- metal polybasic salt has anion-exchanging properties and is useful by itself as an anion exchanger. An anion suitable for the intended application can be incorporated into the salt. The salt is produced by reacting a water-soluble salt of a trivalent metal with magnesium oxide or hydroxide or with a water- soluble salt of magnesium at a pH of 6.0 to 9.0 and a temperature of 50~C or higher and optionally conducting ion exchange in the presence of an acid or a soluble salt of an acid.