Catalytic Deoxygenation of Palm Oil Over Iron Phosphide Supported on Nanoporous Carbon Derived from Vinasse Waste for Green Diesel Production

Abstract

The vinasse waste was effectively converted to nanoporous carbon (NPC) via hydrothermal carbonization with potassium hydroxide (KOH) activation. The nanoporous carbon (NPC) exhibited a maximum surface area of 1018 m2/g and it was utilized as a catalyst for the conversion of palm oil into green diesel fuel. The supported NPC catalyst was fabricated via a wet impregnation technique, where finely distributed iron phosphide (FeP) particles were cemented. The FeP/NPC catalyst was evaluated for its physicochemical characteristics using various techniques including X-ray diffraction (XRD), nitrogen sorption analyzer, transmission electron microscopy (TEM), and energy dispersive X-ray spectrometry (EDS) mapping. An investigation was conducted to examine the effects of different temperatures (ranging from 280 to 360 °C) on the conversion of palm oil through deoxygenation reactions. The FeP/NPC catalyst exhibited remarkable particle dispersion and surface area. At a reaction temperature of 340 °C, the FeP/NPC catalyst had the best selectivity for green diesel, reaching 68.5%. The finding implies that FeP catalysts, when supported, hold significant promise for converting triglycerides into renewable diesel fuel. Moreover, they provide the advantage of being more cost-effective than valuable metals, while demonstrating excellent catalytic efficiency in the production of biofuels. Furthermore, it has been shown that the FeP/NPC catalyst can be recycled by subjecting it to heat treatment to remove impurities and obtain reduction.