EFFECT OF PALM EMPTY BUNCH ASH ON TRANSESTERIFICATION OF PALM OIL INTO BIODIESEL

Abstract

Biodiesel conversion from transesterification reaction palm oil with methanol was studied by using an ash of palm empty bunch as a base catalyst. Atomic absorption spectroscopy (AAS) and indicator titration analysis were used as tools for characterization of ash sample. Chemical structure of biodiesel was analyzed by GC-MS. The effects of ash sample weight (5, 10, 15, 20 and 25 g) immersed in 75 mL methanol and the methanol-palm oil mol ratio (3:1; 6:1; 9:1 and 12:1) toward the conversion of biodiesel were investigated. Biodiesel was prepared by refluxing palm oil and methanol containing ash sample. The reflux was done at room temperature for 2 h. Ester layer was distillated at 74 oC, extracted with aquadest and then dried using Na2SO4 anhydrous. The product was characterized by GC-MS, ASTM D 1298 (specific gravity 60/60 °F), ASTM D 97 (pour point), ASTM D 2500 (cloud point), ASTM D 93 (flash point), ASTM D 445 (kinematics viscosity 40 °C) and ASTM D 482 (ash content). The result of GC-MS analysis showed that methyl palmitate is primary content of biodiesel product. A 15 g weight of ash sample gave the maximum biodiesel conversion. By increasing methanol mole quantity, biodiesel conversion increased progressively and maximum at 9:1 methanol-palm oil ratio (84.12 %) and decreased on 12:1 ratio (75.58 %). Most of the biodiesel products were similar to those of the diesel physical characters. Keywords: Biodiesel conversion, transesterification, palm oil, palm empty bunch