Thermal and catalytic pyrolysis of sunflower oil using AlMCM-41

This study was conducted on thermal pyrolysis and thermal-catalytic pyrolysis using the AlMCM-41 catalyst with a Si/Al ratio of 50, as an alternative process for turning sunflower oil into biofuel. The catalyst was characterized by X ray diffraction (XRD), N2 adsorption/desorption and total acidity by adsorption of n-butylamine, in which it was confirmed an obtainment of AlMCM-41 with an excellent surface area of 857.7 m2 g−1 and good total acidity. TG curves were used to determine the calcination temperature (450 °C) and the infrared spectroscopy (FTIR) confirmed a complete removal of the CTMA+. Two liquid fractions were obtained from the thermal and thermal-catalytic pyrolysis of sunflower oil: the first, named bio-oil, is a mixture of hydrocarbons similar to mineral diesel; the second, which was named acid fraction, is composed mainly of high acidity components. It was found by gas chromatography (GC/MS) and infrared spectroscopy (FTIR) that the proportion of acid present in the fraction of bio-oil without catalyst is higher than the proportion of acids in the fraction of bio-oil with catalyst, which indicates that the deoxygenation of the products occurred. Thus, it can be noted that the thermal catalytic sample of the bio-oil features more appropriate results to the diesel range, indicating that the acid sites found in AlMCM-41 catalysts were effective for the oil pyrolysis.