Renewable hydrocarbons via catalytic pyrolysis of sunflower oil using in situ metal-modified MCM-41

Abstract

Extracting hydrocarbons from renewable sources is a key goal in the chemical industry. To achieve this, utilizing more efficient and selective catalysts during the conversion process is essential. This study developed metal-modified (La and Ni) mesoporous MCM-41 catalysts for the catalytic processes of thermodegradation and fast pyrolysis of sunflower oil. Lanthanum- and nickel-modified on mesoporous molecular sieve (MCM-41) were synthesized in situ by hydrothermal method. The catalysts were characterized by Thermogravimetric analysis (TG), X-ray diffraction (XRD), X-ray fluorescence (XRF), Fourier Transform Infrared Spectroscopy (FTIR), Nitrogen adsorption-desorption at 77 K, and Transmission electron microscopy (TEM). The catalysts performance was evaluated by catalytic thermodegradation (Thermal analysis– TG, DTG and DSC) and fast pyrolysis (Pyrolyzer gas chromatography mass spectrometry– Py-GC-MS). Nickel- and Lanthanum-modified MCM-41 by in situ methodology increased the mesopore parameter, exhibiting metal-silica interactions, resulting in Si/Metal mass ratios of 48 and 77, respectively. The catalytic thermodegradation of sunflower oil shows that Ni-MCM-41 is more active than La-MCM-41. Ni-MCM-41 exhibited the highest deoxygenation activity, producing 56.37% hydrocarbons and achieving a 6.50% reduction in oxygenates compared to the thermal process. Both La-MCM-41 and Ni-MCM-41 catalysts showed high hydrocarbons production compared to thermal process, favoring the formation of compounds containing 14 and 17 carbons, respectively. These findings highlight the effectiveness of Nickel and Lanthanum metal-modified MCM-41 catalysts in producing renewable hydrocarbons from sunflower oil pyrolysis.