Modified of CaO-Nanoparticle Synthesized from Waste Oyster Shells with Tin Tailings as a Renewable Catalyst for Biodiesel Production from Waste Cooking Oil as a Feedstock

Tin tailings were chemically connected to the surface of modified CaO in a straightforward manner to produce fatty acid methyl ester (FAME) from waste cooking oil(WCO) with great efficiency. After 3 h at a reaction temperature of 80 °C, it was discovered that WCO could produce 98.7% yield of the FAME of the modified CaO, which is much greater than the yield of 83.5% over unmodified CaO under the same reaction circumstances. The reaction time to get the greatest yield of 98.7% during the transesterification of WCO and methanol was reduced to 3 h. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) method were used to assess the microstructure and phases characteristics of the catalysts. The results showed that following modification, well-dispersed CaO with relatively tiny particle sizes and large surface areas was produced. Additionally, the changed CaO has very little Ca(OH)₂ is produced during the modification process. In-depth research was done on the effects of the quantity of modifier and different reaction parameters, such as the mass ratio of catalyst to oil, reaction temperature, and molar ratio of methanol to oil. Additionally, water was added to the reaction system to evaluate the modified CaO's water tolerance. In terms of physiochemical qualities, the biodiesel produced fulfills ASTM standards. The use of leftover modified CaO-nanoparticles as a heterogeneous transesterification catalyst has been identified after fourteen cycles.