Biodiesel And Nontoxic Jatropha Meal Production From Jatropha Kernels In Supercritical Carbon Dioxide

Biodiesel is a renewable biomass fuel, which is green, biodegradable and environmentalfriendly. As an alternative fuel for diesel engine, biodiesel gained an important positionregarding to the oil crisis and environmental concerns in the recent years. Intraditional biodiesel process, oil crops should be shucked, grinded, pressed or solventextracted to obtain crude oil firstly, then it can be prepared biodiesel with methanol afterrefining process, such as deacidification, degumming, dehydration, decoloration et. al. Theprocess coupling with extraction and reaction preparing biodiesel and nontoxic Jatrophameal in supercritical carbon dioxide (SC-CO2) from the Jatropha kernels was investigated.The process of preparing biodiesel and nontoxic Jatropha meal in supercritical carbondioxide (SC-CO2) from the Jatropha kernels was investigated. The effects of the moisturecontent and particle size of Jatropha curcas kernel on the fatty acid methyl ester (FAME)content in the biodiesel and phorbol ester (PE) content in the Jatropha curcas meal wereinvestigated. The reaction conditions including the molar ratio of methanol to oil, reactionpressure, temperature and time were optimized by the mono-factor and orthogonalexperiments. When the Jatropha curcas kernel with the particle size of0.25mm and themoisture content of appreciate2.11%is used, the FAME and PE contents achieve95%and0.06mg/g, respectively, under the operation conditions of15MPa,373K,methanol/oil molratio of30:1, and reaction time of150min. The PE content in the Jatropha curcas kernel mealobtained from transesterification in supercritical carbon is below the nontoxic standard.The main properties (density, kinematic viscosity, heat value, flash point, acid value andcetane number) of the obtained biodiesel products satisfied with the current American(ASTM6751-03) and Chinese biodiesel standards(GB/T20828-2007) and can be used as fuel ofdiesel engine.According to Fick’s second law, the dynamic model of biodiesel preparation insupercritical carbon dioxide was established:. The deduced modelfitted the experimental data very well.