摘要 |
Metal cyanide catalysts are prepared by first forming a precipitate using no more than a stoichiometric amount of a water-soluble metal salt of the form MxAy, based on the amount of metal cyanide compound that is used. The precipitate is then treated with an additional quantity of a metal salt of the form M3xAy, in which M3 may be the same as or different than M. The catalyst is treated with a complexing agent, either during the precipitation step or during the subsequent treatment with the M3xAy salt. |