METHOD FOR PRODUCING DOUBLE METAL CYANIDE (DMC) CATALYSTS

The invention relates to an improved method for producing double metal cyani de (DMC) catalysts for producing polyether polyols by the polyaddition of alkylene oxides to starter compounds comprising active hydrogen atoms. According to the inventive method, aqueous solutions of a metallic salt and of a metal cyanide salt are firstly reacted in the presence of an organic compl ex ligand and optionally in the presence of one or more additional complex- forming constituents while forming a DMC catalyst dispersion. This dispersio n is then filtered and the filter cake is subsequently washed by filter cake washing involving the use of one or more aqueous or non-aqueous solutions of the organic complex ligand and optionally the use of one or more additional complex-forming constituents. The washed filter cake is then dried after an optional press drying or mechanical desiccation in the membrane filter press .