Analysis of waste cooking oil biodiesel (WCO) synthesis with TiO2 impregnated CaO from waste shells nano-catalyst

Abstract

The development of clean and renewable energy sources has become crucial due to the rapid rise in crude oil prices, depleting fossil fuel reserves, and increase in environmental pollution caused by various industries. Due to this phenomenon, biodiesel has emerged as a renewable and eco-friendly alternative to conventional diesel fuel because it is non-toxic and biodegradable. WCO is one of the best resources in biodiesel production which has a high potential such as saving ecological systems, improving pollution by clean emissions, preventing food supplies and more economic. However, this WCO cannot be used directly in diesel combustion engines due to their properties are not good as diesel fuel. Thus, it needs to be converted as biodiesel fuel before apply. In the biodiesel synthesis process, the catalyst for instance KOH, NaOH, HCL, H2SO4 etc. plays a significant role to increase their yield but also needs a washing process. Currently, the synthesis of WCO biodiesel using CaO-TiO2 nanoparticles as a catalyst could be an excellent alternative because it eliminates the biodiesel’s washing step and the catalyst can be reused. Hence, the cost of biodiesel production will be reduced. CaO catalyst was produced by using waste cockle and sea snail shells as a cost-effective and environmentally friendly heterogeneous catalyst. In addition, TiO2 impregnated CaO nanoparticles also have been studied through the ultrasonication process for the improvement in thermo-physical properties of catalyst reaction. It showed that the 15:1 ratio is the ideal ratio for the conversion of biodiesel production for both catalysts, which are 94.58% by using CaO catalyst and 98.78% by using CaO-TiO2 catalyst. Furthermore, the optimum average reaction time is 150 min, equivalent to 2.5 h and catalyst loading is 2.3 wt%.