Transesterifrication Optimization of Sterculia foetida Biodiesel and Its Quality During Storage

Abstract

The availability of natural oil is decreasing rapidly. Therefore, alternative fuel is needed. Biodiesel is one of alternative fuel which can replace diesel fuel. Kepuh (Sterculia foetida) oil can be converted to biodiesel because the kernel of its seeds contain more than 25% oil. In this study, transesterification optimization is done to the oil of Kepuh under a variety of methanol and KOH concentration. The acid value of the oil and the biodiesel were also analyzed during storage. The best quality of biodiesel was prepared by using 20% methanol and 1% KOH with acid value at 0,36 mg KOH/g, kinematic viscosity at 4,28 cSt, and density at 880,7 kg/m3. The acid value of raw oil, degummed oil, and biodiesel in the storage increased significantly especially in the open storage therefore oil and biodiesel is better stored in closed container.