ENHANCING BIODIESEL PRODUCTION VIA HETEROGENEOUS CATALYSIS TRANSESTERIFICATION BY USING PHYSICAL PROCESSES: MICROWAVE AND ULTRASOUND UTILIZATION

摘要

In the biodiesel production, via transesterification, physical methods have been tested to improvernefficiency. In this research activity, the microwave have been tested to reduce the reaction time in a continuousrnprocess. Moreover, ultrasound utilization has been investigated as effective in order to improve biodiesel synthesisrnvia transesterification process. Experiments have been carried out at bench scale by using soybean oil and methanolrn(molar ratio alcohol/oil 6:1); as catalyst 1% NaOH or 10% triphosphate potassium were used. For microwave tests,rnreactants have been injected in a 5.0 m pipe that was inserted in a microwave oven; the product has been recoveredrnoutside the oven. Obtained results are very promising. Ultrasound experimental tests were carried out in a batchrnreactor (500 ml flask) with a condenser, hot bath, magnetic stirrer and/or an ultrasound probe system. As matter ofrnfact, experimental tests carried out by using microwave have pointed out that microwaves can be usefully employedrnto perform the transesterification of vegetable oils and to reduce reaction time. Moreover, ultrasound seems to bernmore effective than magnetic stirrer.