Preparation, characterization and thermoanalytical studies of heterogeneous catalysts of double selenates of Mg/Co and Mg/Cu in biodiesel production using different oils

Abstract

The partial or total replacement of diesel oil used in engines for biodiesel provided the increase in industrial production of biofuels in the national and global scale. The transesterification reaction is considered to be the critical step in this process and must occur in the presence of a homogeneous or heterogeneous catalyst. The homogeneous catalyst, in addition to providing the formation of soap, presents difficult separation from the reaction medium. To solve such problems, and provide a final product with higher purity, heterogeneous catalysis has been extensively studied in the production of biodiesel. Based on the importance of biodiesel production and trying to solve the problems presented by homogeneous catalysis, the main objective of this work is to prepare heterogeneous catalysts from Magnesium and Copper double selenates, Magnesium and Cobalt double selenates, its mixed oxides formed from its thermal decomposition and evaluate their catalytic activities with these compounds supported and not supported on zirconia nanoparticles (ZrO2). The catalysts will be characterized by simultaneous thermogravimetry and Differential Scanning Calorimetry (TG-DSC), vibrational spectroscopy in the infrared region (FTIR), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM-FEG), transmission electronic microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), N2 physisorption and temperature programmed desorption (TPD) with ammonia and CO2. In order to determine the optimum conditions for the production of biodiesel employing these catalysts experimental design chemometric strategies will be applied and the products obtained from the transesterification reaction of soybean oil, macaw palm oil and residual frying oil (the latter two as promising sources of raw materials) will be characterized by TG-DSC, FTIR, flame atomic absorption spectrometry (FAAS), and gas chromatography (GC). Furthermore, the GC will also be used to assess the catalytic efficiency of the catalysts. (AU)