Prokaew A.Smith S.M.Luengnaruemitchai A.Kandiah M.Boonyeun S.Mahidol University2023-06-182023-06-182022-01-01Journal of Metals, Materials and Minerals Vol.32 No.1 (2022) , 79-8508576149https://repository.li.mahidol.ac.th/handle/20.500.14594/84643Biodiesel production from waste palm cooking oil (WPCO) was studied. Calcium oxide with a strontium ion additive (Sr-CaO) was employed as a catalyst in transesterification reaction of used palm oil with methanol. The Sr-CaO was synthesized by co-precipitation method between SrCl2 and Ca(NO3)2, then calcined at 900°C for 5 h. The catalyst was characterized by using thermo-gravimetric analysis (TGA), X-ray diffraction (XRD), Scanning electron microscope (SEM), and Fourier transform infrared spectrometer (FT-IR). The morphology and elements content of Sr and Ca in the catalyst were confirmed by SEM-EDX. The approximate catalyst diameter is 12.6±5.9 μm. The highest conversion was 99.33% (the reaction time 3 h, 5%w/w catalyst, methanol to oil molar ratio 9:1 and reaction temperature 80°C). The catalyst can be used up to the sixth cycles with a good yield. The synthesized biodiesel meet the requirement of standard biodiesel (EN 14103 and ASTM D445). These findings suggest that calcium oxide with a strontium ion additive (Sr-CaO) is an effective renewable biodiesel catalyst.EngineeringArticleSCOPUS10.55713/jmmm.v32i1.11492-s2.0-8512924924026300508