Regeneration of Spent Bleaching Earth and Reuse in Crude Palm Oil Purification.

Abstract

Bleaching earth (BE) is commonly used term in trading for a clay with montmorilonite structure. The increasing of BE consumption in crude palm oil (CPO) purification will increase the spent bleaching earth (SBE) amount. BE is a non-renewable natural resources. Regeneration of SBE will save BE consumption. The regeneration process in this research employed physical-chemistry process, by using H2SO4 in acidification and continued with heating. Besides direct regeneration, regeneration was also carried out with preoxidation using H2O2 30%. Parameter used were H2O2 30% (v/v), H2SO4 with 10 and 30% (v/v) of concentration variations, and temperature of 700 °C. Heating at this temperature were varied for 1, 2, and 5 hours. The result showed that the best adsorption efficiency of CPO dyes (98.44%) was after being bleached by using the regenerated SBE with H2SO4 30% and 2 hours calcination. This result was close to the efficiency of commercial BE, which is 98.46% and met the requirements from Standar Nasional Indonesia, that is higher than 40%.