Influence of catalyst preparation conditions on coconut shell-derived solid acid catalyst performance for transesterification

Abstract

The carbon-based solid acid catalyst is mostly synthesized through a series of incomplete carbonization and sulfonation process. This paper investigates the influence of catalyst preparation conditions on the catalyst performance in biodiesel conversion. Coconut-shell-derived solid acid catalyst was prepared through incomplete carbonization followed by sulfonation using concentrated sulphuric acid. The effect of catalyst preparation variables including carbonization temperature, carbonization time, sulfonation temperature and sulfonation time was evaluated using response surface methodology. The adequacy of the mathematical model represents the process was confirmed by using ANOVA analysis with R2 value of 0.9121 and p-value <0.0001. Optimal process conditions were obtained at carbonization temperature of 469.97 ºC, carbonization time of 3.37 h, sulfonation temperature of 99.14 ºC and sulfonation time of 7.11 h. At these conditions, the coconut shell-derived catalyst able to catalyse the transesterification reaction and achieved >80% FAME conversion. This study uncovers the potential of biomass valorisation into a useful end produc.