Produção de biodiesel por transesterificação utilizando catalisador heterogêneo (KOH/Al2O3)

Abstract

Biodiesel consists of a biodegradable fuel derived from vegetable oils and animal fats, formed of fatty acid esters, alkyl esters (methyl, ethyl or propyl) of long chain carboxylic acids. The conventional process for its production occurs by transesterification of vegetable oils with short chain alcohol in the presence of a catalyst. The catalyst most used in the transesterification process is the homogeneous catalyst, as example KOH, which presents great difficulty in recovering the same, therefore a heterogeneous catalyst (KOH/Al2O3) was used in this work. The aim of this work is to synthesize and characterize the KOH/Al2O3 catalyst, in addition to applying the catalyst in the cotton oil transesterification reaction in search of the best reaction conditions, to analyze and evaluate the product obtained by density, viscosity, thermal analysis And infrared spectroscopy (FTIR). The X-ray diffractometry (XRD), X-ray fluorescence (FRX) and scanning electron microscopy (SEM) techniques were used to confirm the catalyst. The biodiesel obtained by the transesterification reaction in the presence of (KOH/Al2O3) was evaluated by the density, viscosity and acidity tests according to ANP Resolution 45/2014. Through the thermal analysis and FTIR it was possible to evaluate the transesterification process and to determine the content of esters obtained. When the best reaction conditions were studied (time, temperature, ethanol, oil, catalyst), the best yield for the 5-hour reaction parameters was ethanol: 15: 1 oil, 60 ° C and 4% of catalyst.