Cokery wastewater (pH 9.13) was purified by vacuum pervaporation to remove org. compds. with arom. rings (PhOH, p-cresole, quinoline) of high toxicity. The pervaporation process was carried out periodically at 50-80 degrees C and 12 hPa in a plant with a membrane separator. The com. membrane made of polidimethylsiloxane and polyacryinitrile (surface 0.0178 m(2)) was used. The feedstock was recirculated ((2-9.37).10(-5) m(3)/s). The PhOH flux through the membrane showed a max. at pH below 6 and rapidly decreased with the increasing pH of the feedstock. The total org. C flux decreased with the decreasing its content in the feedstock. The exptl. data agreed well with mass transfer model adopted.