Process for preparing solid titanium trichloride useful for the polymerization of an alpha-olefin.

摘要

A process for preparing solid titanium trichloride useful for the polymerization of an a-olefin, which comprises precipitating violet-colored fine solid particles of titanium trichloride at a temperature of not higher than 150°C from a liquid of titanium trichloride liquefied in the presence of an ether, characterized in that after the amount of the precipitated violet-colored fine solid particles of titanium trichloride reaches at least 80% based on the total amount of titanium trichloride in the system, titanium tetrachloride is added in an amount within a molar ratio of from 0.2 to 10 based on the total amount of titanium trichloride in the system, followed by ageing at a temperature of from 60 to 120°C.