Production of petroleum-like synthetic fuel by hydrocracking of crude soybean oil over ZSM5 zeolite – Improvement of catalyst lifetime by ion exchange

Abstract

It is possible to produce hydrocarbons by hydrocracking of biomass, such as those produced by crude oil cracking. This product can be incorporated as raw material in petrochemical industry and used as petroleum fractions without any changes on engines. The hydrocracking process was performed over NaZSM5 and HZSM5, where the improvement of this acidity was carried out by ion exchange with ammonia followed by calcination. The reactions were performed on a stainless steel fixed bed reactor. The catalyst was evaluated at 723K and 138kPa, under flow of hydrogen gas, with weight hourly space velocity (WHSV) of 4h−1. Products are analysed by gas chromatography with mass spectra detector (GC–MS) and by nuclear magnetic resonance (NMR) of 1H. For the fresh catalyst, all triglyceride was converted to hydrocarbon by the process. For NaZSM5, the catalyst activity is high but has a high decrease over the time of reaction. It was changed for HZSM5, where the catalyst maintained a high activity even after 90min of reaction. This treatment improved also the product, where a high yield of gaseous hydrocarbon was changed to a high yield of liquid hydrocarbon, especially by the presence of aromatics molecules.