Esterificação em meio continuo pressurizado em reator de leito fixo com presença de inertes

Abstract

Research on biodiesel production has been intensifying over the years in order to meet the best environmental and economic conditions. The chemical route commonly used for the production of biodiesel is the transesterification and catalytic esterification using homogeneous catalysts or basic) or heterogeneous. In spite of this, this route has several disadvantages concerning to the conversion values as well as the separation of the products obtained at the end of the process, besides the high sensitivity to impurities that may be present in the oils used. As an alternative, biodiesel production has been studied under supercritical conditions. The main advantage to be highlighted is the dispensability of the use of catalysts, which implies in the reduction of separation costs. The present work presents a study of the esterification reaction between oleic acid and ethanol under supercritical conditions conducted in a tubular reactor in a continuous way. The effects of temperature (300, 350 and 400 ° C), residence time (3.23 and 6.46 min) and molar ratio (oleic acid: ethanol) (1: 1, 1: 3, 1: 6, 1:10, 1:20, 1:30, 1:40, 1:50, 1:60 and 1:70) in biodiesel production at a pressure condition of 15 MPa. Under the conditions operated, the effects of temperature and residence time were positive in all cases and a conversion peak was observed at a ratio of 1: 6. A comparison of the conversion values obtained for all molar ratios at 350 ° C and 15MPa pressure was also performed, considering the reactor without and with inert fillers (porosity 0.38). Under the conditions specified for temperature and pressure, and in the presence or absence of inert filling, conversion values above 96% were obtained.