Production of acylglycerol catalysed by rice bran lipase in a packed bed reactor

A 20 litre packed bed reactor (PBR) with heating and water removal system was designed and fabricated for the esterification of palm oil fatty acid distillate (PFAD) catalyzed by immobilized rice bran lipase (RBL). The PBR was designed based on the characteristics of immobilised RBL and the optimized esterification conditions obtained from method scouting performed in shaked flask. The optimal ratios of immobilised RBL and water removal agent (silica gel) to PFAD for the shaked flask esterification process were 5:1 and 1:2, respectively. The intensified esterification reaction of PBR was operated by circulating the reaction mixture (PFAD and glycerol) in hexane through a packed bed column filled with immobilised RBL. The water generated from esterification reaction was absorbed by silica gel filled in the water removal vessel. The maximum degree of esterification achieved in this developed PBR was 61%. The reaction time required to achieve the maximum degree of esterification was 25% faster than that in the shaked flask

Rice bran lipase catalyzed esterification of palm oil fatty acid distillate and glycerol in organic solvent

Rice bran lipase (RBL) was delipidated to enhance its stability in organic solvent and its esterification activity at elevated temperature. The esterification activity of delipidated RBL increased as temperature was increased from 45 to 65°C. The esterification activity of delipidated RBL at 65°C was about 14 times greater than that of the non-delipidated RBL. As temperature was further increased to 75°C, the non-delipidated RBL lost all esterification activity, whereas the delipidated RBL retained approximately 48% of its esterilication activity. The delipidated RBL maintained a relative esterification activity greater than 80% after 16 h of incubation in hexane, whereas the non-delipidated RBL maintained a relative esterification activity of only 50%. A method for production of acylglycerol using delipidated RBL to esterify palm oil fatty acid distillate (PFAD) with glycerol in hexane was successfully developed. The effects of reaction temperatures and type of water removal agents (silica gel and molecular sieve) on the degree of esterification were also examined. A 4 h reaction at 65°C, catalyzed by delipidated RBL and using silica gel as the water removal agent resulted in 53.8% esterification. Thin layer chromatography analysis suggested that the esterified product was primarily comprised of mono-and di-acylglycerols