PROCESS FOR PRODUCTION OF DIALKYL PHOSPHATE ESTER RARE-EARTH SALT OR DIOLEYL PHOSPHATE ESTER RARE-EARTH SALT OF

摘要

Disclosed is a process for producing a highly pure dialkyl phosphate ester rare-earth salt or dioleyl phosphate ester rare-earth salt which is useful as a polymerization catalyst for a conjugated diene polymer, by directly reacting a rare-earth oxide or a rare-earth hydroxide with a highly pure dialkyl phosphate ester or dioleyl phosphate ester. In the process, the rare-earth oxide or the rare-earth hydroxide is reacted with the highly pure dialkyl phosphate ester or dioleyl phosphate ester in a non-polar solvent in the presence of at least one compound selected from a hydrohalic acid, a phosphorous acid and a rare-earth halide composed of elements that are the same as or different from those contained in the desired product as a catalyst.