Removal of organic salts from bio-derived glycol products of polyol hydrogenolysis

A method of manufacturing propylene glycol or ethylene glycol, the method comprises providing a biologically-derived feedstock of three, five, and six carbon sugars or sugar alcohols;

• converting by hydrogenolysis said feedstock in a reactor to a reaction product mixture containing polyols and impurities;
• subjecting said reaction product mixture to ion-exclusion chromatography to reduce said impurities from an eluant fraction containing propylene glycol or ethylene glycol;
• distilling said eluant fraction through a distillation system having a first column that removes alcohols, a second column that removes water, a third column that removes unreacted components or organic components having higher boiling points than that of ethylene glycol, a fourth column that removes ethylene glycol, and a fifth column that removes epoxides, esters, C4 C5 and higher diols, residual water and propylene glycol.