Water-dispersible aluminium oxide prepn - contg a metal salt, pref. chloride or nitrate of aluminium, iron, chromium or tin

摘要

Aluminium oxide, esp. alpha-aluminium oxide monohydrate produced by hydrolysis of an aluminium alcoholate, is rendered dispersible in water by dry-mixing it with a salt to produce a preparation contg. 99.9-66.67 wt.% of aluminium oxide monohydrate and 0.1-33.33 wt.% (pref. 3-10 wt. %) of a salt having the formula MX, in which M is a metal whose hydroxide is scantily soluble (its solubility product is less than 10-20) and X is an anion derived from a monobasic acid whose ionisation constant exceeds 10. This method is superior to the conventional dispersing of Al2O3 in water by treatment with an acid resulting in corrosion of containers. They dry alumina-salt mixture is easy to transport and handle.