Waste cooking oil is increasingly becoming a significant component of biodiesel feedstock and its conversion to FAME requires coupling of esterification and transesterification processes. In this study, new
environmentally benign catalysts were prepared from oil palm trunk and sugarcane bagasse, which
are sustainable because of the superfluity of oil palm trunk and abundant supply of bagasse. Effect of
preparation variable, surface acidity and textural properties, pre-esterification of FFA in oil matrices
and transesterification of waste oil under pseudo-infinite methanol and conventional methods were
investigated. The preparation variable, H2SO4impregnation time showed marginal effect on sulfonic acid
density after 6 h, and the corresponding values for 6–10 h impregnations were 1.33 ± 0.01–
1.41 ± 0.01mmol g
1
for OPT and 1.44 ± 0.01–1.48 ± 0.01mmol g
1
for SCB catalysts. In esterification of
palmitic acid, activity of catalysts with different H2SO4impregnation time correlates with their sulfonic
acid density. The catalysts demonstrated rapid esterification of FFA in oil matrices under pseudo infinite
methanol, reducing its content from 42 wt.% to