Possibilities for alkaline transesterification of rapeseed oil for biodiesel fuel production

The present research work deals with the possibilities for alkaline transesterification of raw rapeseed oils with high levels of free fatty acids content and the opportunities to obtain the respective methyl esters (ME) of these oils, which are suitable for use as bio diesel fuel. The object of research are the process parameters (temperature, catalyst quantity, reaction time, molar ratio alcohol/oil), as well as the reaction between them depending on the quantity of the fatty acids. The results and the course of the process are compared based on their physical and chemical properties. We have traced the extent of secondary reactions process, leading to decrease in the yield (soap formation, hydrolysis, etc.) in the use of alkaline catalyst (potassium hydroxide). As a result of the study it has been established that a successful transesterification. of rapeseed oil with acid value 8.92 mg KOH/g is obtainable under the following reaction conditions: reaction time 30 min.; catalyst quantity 2.8% (compared to the oil mass); methyl alcohol excess of 3.6 mol (compared to the stoichiometric quantity) and a temperature of 25 degrees C.