BULK SEPARATION OF POLYHYDRIC ALCOHOLS BY SELECTIVE ADSORPTION ON ZEOLITIC MOLECULAR SIEVES

摘要

BULK SEPARATION OF POLYHYDRIC ALCOHOLS BY SELECTIVE ADSORPTION ON ZEOLITIC MOLECULAR SIEVES The instant invention relates to a process for the separation of mixtures of polyhydric alcohols, said mixtures comprising mannitol and one or more members of the group consisting of sorbitol and galactitol, by selective adsorption which comprises contacting a mixture comprising said compounds at a temperature of from 30.degree.C to 100.degree.C and at a pressure sufficient to maintain the system in the liquid phase with an adsorbent composition comprising at least one crystalline aluminosilicate zeolite selected from a group consisting of zeolite type X and zeolite type Y in which the zeolitic cations which occupy more than 55% of the available cation sites are selected from the group consisting of barium and calcium; whereby a polyhydric alcohol is selectively adsorbed thereon, removing the non-adsorbed portion of said mixture from contact with the zeolite adsorbent and desorbing the adsorbate therefrom by contacting the desorbed polyhydric alcohol.