Waste Cooking Oil Purification with Various Adsorbents for Synthesizing Biodiesel and Soap Sri Mulyani*, Endang Susilowati, Elfi Susanti VH, and Adi Muhammad Falah Sutopo
Chemistry Education Study Program, Teacher Treaning and Education Faculty,
Universitas Sebelas Maret, Indonesia
This research aims to: (1) activate the rice husk ash (ASP), coconut shell ash (ATK), and wood charcoal (AK) and characterize them using SEM and FTIR, (2) purify waste cooking oil using rice husk ash (ASP), coconut shell ash (ATK), and wood charcoal (AK)- (3) make biodiesel and soap using purified waste cooking oil, and (4) characterize the quality of biodiesel and soap made from the purified waste cooking oil. This research used experiment method. The outline of this research was consisted of 5 steps in chronological order: activated charcoal activation, activated charcoal characterization using SEM and FTIR, waste cooking oil purification using ASP, ATK, and AK, making biodiesel and soap using purified waste cooking oil, and investigate the adsorbent influence to biodiesel quality produced by purification of waste cooking oil based on their acid number, kinematic viscosity (40˚-C), and flash point. The results were obtained as follows: (1) In the rice husk charcoal (ASP) which has been activated with KOH, there are primary and secondary amine groups as the groups that dominate the charcoal, in activated coconut shell charcoal (ATK), several peaks appeared at 3416 which indicated the presence of an alcohol group (-OH), and at 1556 which indicated the presence of a nitro/aromatic nitro group (-NO2), and in activated wood charcoal (AK) it was seen that there was a shift in peak towards 870.9, which also indicated the presence of other groups (-(CH2)n), (2) biodiesel has been synthesized successfully, made from waste cooking oil purified using ASP, ATK, and AK adsorbent, (3) the best quality of biodiesel was achieved by waste cooking oil purified by ASP adsorbent, based on National Standard (SNI), and (4) the differentiation of biodiesel quality based on acid number, kinematic viscosity (40˚-C), and flash point existed within the use of different adsorbents
