摘要：in this study; degummed and neutralized cottonseed oil is used as raw material; which certainly causes technological problems during bleaching as a result of its considerable gossypol concentration. Therefore; process parameters and adsorbent used is of crucial importance when bleaching cottonseed oil. Beaching experiments are carried out in batches by using two acid activated clays and the process efficiencies of these adsorbents are investigated by correlating the results with Freundlich isotherm to determine the activity constants; namely, K and n values. Moreover; synthetic silica pretreatment is involved prior to bleaching; and the effects of this pretreatment on the bleaching efficiencies of the two clays are investigated. The results showed that, synthetic silica pretreatment increased the adsorption capacity of acid activated bleaching earth especially when processing neutral oils having high soap content and considerable pigment concentration.
