Trans-esterification of waste cooking oil with methanol by electrolysis process using KOH

Biodiesel produced form waste cooking oil (WCO) has increasingly attracted the attentions as an alternative fuel due to lower particulate emissions and other beneficial factors such as low cost. The present study investigated the production of biodiesel (BFD) as one of the effective methods in solving energy crises and environmental pollution. To increase the consumption of biofuels, a high yield biodiesels (96%) was produced as an alternative to fossil fuels by electrolysis method using graphite electrodes through trans-esterification reaction of WCO and KOH in presence of methanol. This reaction was done in 2 h without side saponification reaction. Biodiesel decreases the environmental effects of waste oil and can cause a new application for using the waste oil. The effect of the catalysis amount, oil/alcohol molar ratio, the amount of co-solvent, water amount, reaction temperature, voltage and the reaction time on biodiesel production were investigated confirming this method as a highly effective way for obtaining high yields. Increasing the catalyst beyond a known level decreases the reaction yield due to saponification side reactions; in consequence, an optimum amount of the catalyst should be used. Without inserting the electricity current in the environment temperature, trans-esterification reaction is done slightly in a long time but proper voltage should be used to obtain high yield, complete the reaction and decrease the reaction time. The purpose of this study is to show that the rheology of the biodiesel is a strong function of the shear history.