Pilot evaluation of calcium titanate catalyst for biodiesel production from waste cooking oil

Abstract

The world is gradually moving toward a severe energy crisis due to depletion of fossil fuels. Biodiesel is one of the technically and economically feasible options to solve the aforesaid problem. However, the overall costs of biodiesel production associated with the increasing market price of its feedstock clearly influence the profitability of the process. Therefore, biodiesel production has been directed toward waste materials as feedstock such as waste cooking oil (WCO). On the other hands, WCO is dealing with high free fatty acids (FFA) contents which gives a significant effect to the transesterification reaction, resulting in a lower biodiesel production. Therefore, a viable catalyst is needed for wide industrial usage in biodiesel synthesis from WCO. CaO is one of the promising heterogeneous catalyst for the transesterification reaction. However, CaO is deals with some limitations that need to overcome. This research paper deals with the synthesis of heterogeneous calcium titanate (CT) catalyst from calcium oxide (CaO) and titanium precursor by a sol-gel method for pilot evaluation in biodiesel production. CT catalyst was produced under different calcination temperature (200 °C, 400 °C, 600 °C, 800 °C). The synthesized catalysts were evaluated for performance in transesterification reaction of methanol with WCO. BET surface area, XRD, and SEM were measured to correlate the activity with the structural features of the catalysts. The results exhibited that the calcination temperature of 400 °C is more preferable in terms of technical and economic feasibility. A biodiesel yield of 80.0 % was observed with a methanol to oil molar ratio of 15:1 and 1 wt.% of CT catalyst loading amount in 1 h at 65 °C which is comparative with commercial CaO catalyst calcined at 400 °C (60.0 % of biodiesel yield) at the same reaction conditions.