The re-extraction of oil from oil palm empty fruit bunch residues and oil palm mesocarp fibers and measures in reducing greenhouse gas emission

摘要

Oil palm Mill (POM) produces oil palm empty fruit bunches (EFBs) and oil palm mesocarp fibers (OPMF) which still contain oil and carotenoids. POM utilizes EFBS and OPMF as a fuel to heat up the boiler and to generate electrical energy leading to the dissolve of oil and carotenoids in vain and causes greenhouse gas (GHG). The research is aimed at isolating and investigating the quantity and quality of oil of EFBS and OPMF, OPMF oil characteristics comprising of fatty acid composition and antioxidant activity and to determine the effect of GHG emission reduction after OPMF oil is macerated. The residual sample used is collected from 4 POMs. Oil isolation was done by maceration. EFBS and OPMF were compared with a hexane ratio of 1:20 (w/w), while the duration for maceration lasted for 48 hours in a room with temperature. Oil quantity parameters include residual oil content with soxhlet method and macerated oil yield. Oil quality parameters include: carotenoid levels, deterioration of bleachability index (DOBI) and free fatty acids (FFA). OPMF oil characteristics included oil fatty acid composition which was determined by GC method and antioxidant activity with 1,1-Diphenyl-2-picrylhydrazyl (DPPH) and GHG reduction by emission factor method. The quantity and quality of oil isolated from OPMF residues is higher than oil isolated from EFBS due to: oil content was higher by 3.91% (2.86% in EFBS), oil yield was 3.47% (2.26% in EFBS) carotenoid levels were higher at 2305 ppm (915.25 ppm in EFBS), DOBI is higher by 3.49 (1.14 in EFBS), and FFA is lower by 9.68% (21.58% in EFBS). The fatty acid in OPMF oil has generally the same composition as the CPO fatty acid which is dominated by palmitic acid by C16:0 and oleic acid by C18:1, respectively at an average of 30.31% at CPO of 44.0%) and 33.22% at CPO of 39.2%). OPMF Oil antioxidant activity half maximal inhibitory concentration (IC50) was at 8.49 ppm. The effect of GHG emission reduction after OPMF oil macerated could reach 88.77% of the total amount of GHG emissions resulted from OPMF burning before maceration.