Process Optimization of Biodiesel Production from Sal Seed Oil using Response Surface Methodology [RSM] and Diesel 2015-01-1297

Biodiesel production has been getting global awareness since Petroleum prices are escalating continuously. As biodiesel is gaining considerable demand, standards are vital for its commercialization and market introduction. Feedstocks availability has posed serious challenges, thus the need for non-edible and unexplored feedstocks has risen. In Indian context, Biodiesel is produced using sal seed oil which is potentially available in Indian forest as a non-edible feedstock. The present paper deals with the production optimization using design of experiments and fuel property characterization of Sal biodiesel (sal methyl esters). Transesterification process parameters like catalyst concentration (% w/w), Oil to Methanol molar ratio, reaction time (min) and reaction temperature (°C) were considered the significance factors and the response was taken as the Yield (% w/w). Experiment matrix with several combinations of factors was generated. The results of the experimental matrix were analyzed. The FFA content of Sal seed oil was 1.68% which is below the 2% recommended for the application of the one step alkaline transesterification method. It was found that the optimal reaction conditions were Potassium hydroxide (0.57 %w/w), methanol/oil molar ratio was 7.16, reaction temperature was 59.43°C and at constant reaction time 60 (min). The biodiesel yield of 94.48 (% w/w) was recovered. Depending on the degree and extent of the factor interactions, synergistic and antagonistic parametric effects were also observed. Most contributions were noted for the individual factor contributions, especially with regard to reaction temperature, catalyst concentration and molar ratio. The properties of Sal biodiesel determined were within the recommended biodiesel standards limits. Various Physico-chemical properties like density, viscosity, calorific value, Cold Flow Plugging Point (CFPP), oxidation stability were evaluated. Properties were found to be comparable with respective ASTM biodiesel standards.