The influence of the addition H₃PO₄ on degradation of glycerol with vibrating horn

Indonesia is currently developing a renewable energy-based vegetable oils include the development of biodiesel. One way of making biodiesel is the transesterification process from vegetable oils and ethanol/methanol. The transesterification process will produce primary products such as methyl ester and byproducts/waste in the form of glycerol approximately 10-15 % so that glycerol is quite abundant. Degradation of glycerol were processed by the method of sonication can produce many other compounds include acrolein. The purpose of this study was to determine the effect of phosphoric acid catalyst in the degradation of glycerol. The process of production is done in sonication reactor type 316 stainless steel is equipped with an ultrasonic wave generator. The operating conditions of research are atmospheric pressure with water glycerol mass ratio is 1: 8. Research variable is the temperature of sonication 30, 40 and 50 °C, sonication time is 10, 30, 50, 70 and 90 minutes with and without the use of catalysts. Results of the experiment were analyzed by using Gas Chromatography (GC). The results showed that the ultrasonic wave radiation for glycerol degradation process can be used to produce other compounds such as acrolein and others. With the use of H₃PO₄ catalyst conversion is greater than without using a catalyst and increases with sonication time. The highest conversion obtained with the use of catalysts H₃PO₄ is 72.68 % in the sonication time of 90 minutes and a temperature of 50 °C, while the highest yield obtained was 49.50 % with the use of a catalyst H₃PO₄ at sonication time of 90 minutes and a temperature of 50 °C.