Rapid monitoring of fatty acid methyl ester in sonochemistry transesterification process using attenuated total reflection

The transesterification process with conventional techniques usually based on use of stirring method typically over temperatures range of 70–200 o C, and reaction times of up to 1 h for achieving conversions reaction in the range of 90–95 mol%. The low rate of time chemical reaction will influence the high cost of biodiesel processing. Sonochemistry using ultrasound reactor is expected to increase reaction time with their cavitations effect. Production Fatty Acid Methyl Ester (FAME) from Jatropha Curcas Oil under ultrasonic using Clamp on Tubular reactor was investigated in this work. Transesterification ultrasonic process was carried out to study the effect of: time processing 5-15 minute, molar ratios of jatropha oil to methanol 1 : 5 to 1 : 9 and quantity of sodium hydroxide catalyst of 0.25 - 1 % w/w. In the present work, FAME and Triglyceride (TG) percentage analyzed using Gas Chromatography to meet the biodiesel oil standard (ASTM D6751). However, GC method requires sample preparation which time-consuming, complicated and high cost. Therefore, an effort to find a simple and rapid analysis method to monitor the formation of TG and FAME is presented. In this research Attenuated Total Reflection (ATR) spectra was used to analyze formation of FAME and TG percentage of transesterification with simple and rapid process. The optimal operating condition was obtained by applying oil to methanol molar ratio of 1: 7 and a catalyst concentration of 1 % w/w. The highest formation of FAME peak was reached at 0.1085A after 5 min of reaction.