Activated carbon supported CaO for conversion of palm oil to biodiesel: Kinetic experiment

Abstract

Biodiesel is one of the bio-energies prepared from vegetable o i l or animal fat through transesterification reaction w i t h methanol. Because of the separation cost a n d associated environmental problems of homogeneous catalyzed biodiesel production, utilization of basic heterogeneous catalysts is steadily increasing in recent years. CaO is among the most solid base catalysts which can be used in transesterification reaction. In this study, activated carbon supported CaO catalyst was used for the transesterification reaction of palm oil. The catalyst was prepared according to the conventional incipient witness impregnation method. Kinetic experiment was performed in a batch reactor in the presence of heterogeneous catalyst for a wide range of operating conditions. The progress of the reaction was monitored using the refractive index method. Response surface methodology coupled with the central composite design was used to screen out t h e operating conditions and optimize the e x p e r i m e n t a l result. A conversion of 34.78% was found at set of optimized conditions (reaction time of 150 min, temperature o f 59.5 0 C, methanol to oil molar ratio o f 19.40:1, and amount of catalyst loaded o f 10.55 (wt.%)). The predicted values of the response surface model were found in a good agreement with the actual experimental values at the aforementioned operating conditions. Moreover, the experimental result demonstrated that a pseudo-first order kinetic model best explains the transesterification reaction. Using graphical method fr om t h e Arrhenius e q u a t i o n , t h e value of activation energy and pre-exponential factor were calculated to be 35.16 kJ mol -1 and 731.43 kJ m o l -1 , respectively.

From Waste to Catalyst: Transforming Mussel Shells into a Green Solution for Biodiesel Production from Jatropha curcas Oil

“…Additionally, when the reaction temperature surpasses the optimal range, biodiesel yields drop due to triglycerides undergoing saponification [45][46][47]. The highest methyl ester production reached 86% under operational conditions after 6 h, highlighting the substantial impact of temperature on oil transesterification [48]. The initial increase in conversion from 3 to 6 h signifies the importance of extended transesterification time for biodiesel yield.…”

“…The catalyst's concentration plays a pivotal role in improving the yield of methyl ester synthesis [29]. The highest yield of 92.78% was achieved at a catalyst loading of 6 wt.%, indicating increased active catalytic sites with a higher quantity [48,56]. However, as the catalyst quantity was increased to 9-12%, the conversion efficiency dropped to 65.89% and 64.88%.…”