a process for recovering double metal cyanide complex catalyst from a polymer such as polypropylene glycol in a form suitable for use as a polymerization catalyst is described . the process comprises the steps of combining the polymer with a non - polar solvent to precipitate the catalyst and filtering the resulting mixture in the presence of a filter aid to separate the polymer from the precipitated catalyst . in contrast to the prior art methods of catalyst removal , the process of the invention yields polymer uniformly low in color as well as recovered catalyst which may be reused in subsequent polymerizations .