A process for preparing a copolymer polyol containing a reduced content of residual monomers and volatiles including the steps of: (a) providing at least one copolymer polyol containing a first initial content of residual monomers and volatiles; (b) providing at least one molecular sieve adsorbent; (c) contacting the at least one copolymer polyol with the at least one molecular sieve adsorbent for a period of time and at a temperature sufficient for the at least one molecular sieve adsorbent to adsorb at least a portion of the first initial content of residual monomers and volatiles present in the at least one copolymer polyol to reduce the first initial content of residual monomers and volatiles of the at least one copolymer polyol to form at least one copolymer polyol containing a second reduced content of residual monomers and volatiles; and (d) separating the at least one molecular sieve adsorbent containing a portion of the first initial content residual monomers and volatiles from the at least one copolymer polyol to form at least one copolymer polyol containing a second reduced content of residual monomers and volatiles.