Analysis and optimization of biodiesel production from Jatropha oil using reactive distillation

Abstract

Biodiesel is considered a potential substitute of fossil fuel as it is clean and renewable. Edible oils such as palm oil and soybean oil are commonly used as feedstock in biodiesel production; however, using these feedstock cause shortage of vegetable oils for human consumption. This study was concentrated on the development of a biodiesel production process from Jatropha oil, a non-edible vegetable oil. As Jatropha oil always contains about 14% of free fatty acid, the biodiesel production process considered consists of a hydrolysis section where triglyceride is converted to fatty acid and an esterification section where fatty acid reacts with methanol in the presence of acid catalyst to produce methyl ester (biodiesel). The utilization of a reactive distillation was proposed to improve the performance of the esterification process. Simulations of the biodiesel production process using a process flowsheet simulator were carried out to identify important operating parameters. The response surface methodology (RSM) based on a central composite design (CCD) was used to determine optimal operating conditions for biodiesel production. The conditions to get optimal response with 99.9% were found to be 126.4 kmol/h of bottom rate, 0.4 for reflux ratio, 160ºC for oleic acid feed temperature, methanol feed stage = 12 and oleic acid feed stage = 3. In order to minimize energy consumption, the pre-heated and methanol recovery of a reactive distillation process is considered.