Process Parameter Estimation of Biodiesel Production from Waste Frying Oil (Vegetable and Palm oil) using Homogeneous Catalyst

摘要

Biodiesel from waste frying oil is an effective alternative fuel for conventional diesel and can be directly used as fuel in a diesel engine without any modifications to the engine. It has many positives like high biodegradability, reduction in greenhouse gas emissions, non-sulfur emissions, non-particulate matter pollutants, low toxicity, and excellent lubricity and is obtained from renewable source like vegetable oils, animal fat, etc. The major objectives of this work were to produce and compare the biodiesel yield from Waste Frying Vegetable Oil (WFVO) and Waste Frying Palm Oil (WFPO) using transesterification process. The physicochemical characterization of the biodiesel, as well as the effects of process variables on biodiesel yield, were evaluated. Also, optimum levels of process conditions for optimum production of biodiesel were determined. The WFVO and WFPO with methanol and catalyst were heated in a hot plate-magnetic stirrer at a temperature of 60°C and operated at 300 rpm. Potassium hydroxide (KOH) was used as catalyst. The one-factor-at-a-time method was used to select the optimum levels of process variable that gives high biodiesel yield. The results showed that the physicochemical characteristics (acid value, free fatty acid, density, kinematic viscosity, pour point and flash point) of the biodiesel obtained from WFVO and WFPO were within the standard value of EN14214 and ASTMD-6751.From the results, the possible optimum conditions of the process variables for transesterification process using KOH catalyst were found to be as follows: reaction time of 90 min, methanol to oil molar ratio of 12:1 and the catalyst loading of 1.5 wt%. At these optimum conditions, the optimum yield of biodiesel obtained from transesterification of WFVO and WFPO were found to be 97% and 90%, respectively. Thus, in comparison, the transesterification of WFVO resulted in higher biodiesel yield than WFPO. Conclusively, both WFVO and WFPO has good potential to be used for bio-diesel production.