CHARASTERISTICS OF CURCAS BEAN BIODIESEL AFTER CATALYTIC CRACKING WITH H-ZEOLITE CATALYST

The development of curcas bean (Jatropha curcas Linn) as a raw material for biodiesel have a very promising potential, because in addition to producing oil with high productivity (40-45%). Curcas bean oil was transesterified at 60oC for 120 minutes to produce biodiesel. The produced biodiesel was the cracked with the H-zeolite catalyst at 70oC, 80oC, 90oC, 100oC, 110oC, and 120oC for 60, 90, and 120 minutes. This study was aimed to characterize the curcas bean biodiesel that had been cracked using H-zeolite catalyst. Characterization of the biodiesel from cracking process included viscosity, saponification number, iodine number, and cetane number. Results of the study indicated that the breakdown of carbon chain in the fatty acid of curcas bean biodiesel can be achieved by catalytic cracking. This was evidenced by the reduced viscosity and iodine number and increased saponification number and cetane number of the curcas bean biodiesel after cracking. Analysis of the curcas bean biodiesel product obtained indicated that the optimum temperature was 90oC and optimum reaction time was 180 minutes. Characteristics of the curcas bean biodiesel on these conditions included the viscosity of 3.850 cSt, saponification number of 206.332 mg KOH/g sample, iodine number of 60.11 mg Iodine/g sample, and cetane number of 68.83. GCMS test on the biodiesel composition indicated the presence of 0.798% of methyl laurate (C13H26O2), 44.527% of methyl palmitate (C17H34O2), 4.584% of methyl linoleic (C19H34O2), 46.506% of methyl oleic (C19H36O2) and 3.584% of methyl stearic (C19H36O2).