Catalytic cracking of Pachira aquatica oil over HZSM-5 for the production of low-carbon transport fuels

Abstract

Biofuel production has made significant progress recently, driven by the increasing demand for energy and the availability of abundant and renewable feedstocks in Brazil. Pachira aquatica Aubl. (PA) seeds are presented as a sustainable alternative for of producing thermally stable oil, which was evaluated in this study to generate renewable hydrocarbon precursors for biofuels via flash pyrolysis. PA oil was extracted by mechanical pressing and characterized to determine its fatty acid profile, followed by catalytic and non-catalytic flash pyrolysis using the HZSM–5 catalyst to produce value-added compounds. Fatty acid analysis revealed a predominance of saturated acids, such as palmitic acid (68.55 %), along with unsaturated acids such as oleic (6.58 %) and linoleic (6.13 %). The oil exhibited thermal stability up to 250 °C. Non-catalytic pyrolysis produced aliphatic hydrocarbons (C7-C16), mainly in the diesel, gasoline, and kerosene range. At 300 °C in a catalytic bed, hydrocarbons in the range of C5–C15 with a drop-in jet fuel profile and aromatic compounds were predominant. At 500 °C, hydrocarbons in the range of C4–C13 with increased aromatic bioproducts (BTEX) were observed. These results demonstrate the significant potential of PA seed oil to produce advanced drop-in biofuels and aromatic bioproducts for the chemical industry. Based on the results obtained, future perspectives include obtaining the products, evaluating the economic feasibility of large-scale PA cultivation to increase oil productivity, as well as expanding its applications to new bioproducts.