KONVERSI ASAM OLEAT MENJADI BIODIESEL MENGGUNAKAN KATALIS HETEROGEN CaO CANGKANG KEPITING TEREMBANKAN ?-Al2O3

Abstract

Heterogeneous catalysts are commonly used in biodiesel production. The CaO heterogeneous catalyst can be prepared by calcination process from one source of CaCO3 prepared from crab shell. The preparation of heterogeneous catalyst was successfully carried out by activation with KOH and doped with ?-Al2O3. The purpose of this study is to determine the characteristics of the CaO/?-Al2O3heterogeneous catalyst and the performance of the catalyst for converting oleic acid into biodiesel. The results of this study that the best characteristics of catalyst were shown by CaO/?-Al2O3 100:7, which has a surface basicity was 20,9532 mmol g-1 with active sites 12,6181x1019atom g-1, and specific surface area of ??42.0979 m2/g. The results of using CaO /?-Al2O3 catalyst for converting oleic acid into biodiesel with the optimum concentration was 5%, the optimum oil/methanol molar ratio of 1:9, and the optimum reaction time of 120 minutes for converting oleic acid into biodiesel with the yield of 89.80%. The characteristics of the final biodiesel obtained had met the Indonesian National Standard (SNI 7182-2015) with density (at 40oC), kinematic viscosity (at 40oC), water content, iodine value were 863 kg/m3; 4.8 cSt; 0.039%, and 35.3562 g I2/100g, respectively. Keywords: CaO/?-Al2O3, oleic acid,biodiesel, heterogeneous catalyst.