Model solutions contg. 1.4-2.5% PhOH, 0.3% Me2CO, and 3% Na2SO4 were batch pervaporated at WC through Sulzer's (i) PERVAP-1060 and (ii) PERVAP-1070 membranes, 1.5 m(2) each, at feed rates of (i) 100 or 150 kg/h and (ii) 100 kg/h. In 10 hours, the deg. of dephenolization was 40-60%. A pervaporation retrofit is suggested to the existing unit to reduce the final concn. of PhOH from 2 to 0.5%.