Hydrodeoxygenation of Stearic Acid into Normal and Iso-Octadecane Biofuel with Zeolite Supported Palladium-Oxalate Catalyst

Abstract

This study reports the hydrodeoxygenation (HDO) of stearic acid (SA) into paraffinic biofuel with synthesized palladium-oxalate zeolite supported catalyst (PdOx/Zeol). The PdOx/Zeol was synthesized via the functionalization of dihydrogen tetrachloropalladate (II) with aqueous oxalic acid (OxA) to form the polynuclear palladium(II) oxalate (PdOx), which was supported on zeolite. The SEM and XRD characterization results showed that the zeolite support is highly crystalline but loss some degree of crystallinity in the PdOx/Zeol sample after PdOx incorporation. The activity of the PdOx/Zeol tested on the HDO of SA showed that temperature, pressure, gas flow rate, and PdOx/Zeol loading have significant effects on the HDO process, and their best observed conditions were 360 °C, 20 bar, 100 mL/min, and 25 mg, respectively to achieve 92% biofuel production from 35 g SA. The biofuel product distribution showed 71% n-C18H38, 18% iso-C18H38, and 3% C17H36. The presence of iso-C18H38, which is an excellent biofuel va...