Production of renewable aromatic hydrocarbons via conversion of canola oil methyl ester (CME) over zinc promoted HZSM-5 catalysts

The conversion of canola oil methyl ester (CME) to aromatics was studied over Zn-modified HZSM-5 catalysts. The catalysts were prepared by incipient wetness impregnation method. Several techniques were used in characterization of the catalysts: X-ray diffraction, scanning electron microscopy, transmission electron microscopy, N2 adsorption-desorption and ammonia temperature-programmed desorption. The effects of reaction temperature and Weight Hourly Space Velocity (WHSV) on the aromatics yields were investigated. The reactor was operated at atmospheric pressure, temperatures of 400 and 450 °C and space velocities of 2 and 4 hr−1. The main products were liquid hydrocarbon product (LHP), gases and water. Gas Chromatography (GC) analysis was applied to determine the BTX content of the LHP. Similar aromatic products distributions were obtained in the presence of unpromoted as well as Zn-promoted HZSM-5 catalysts. Toluene was the major aromatic compound followed by para-meta xylenes and benzene. The addition of zinc species to HZSM-5 catalyst promoted the aromatization capacity of the catalyst. The maximum aromatic yield of 42.6% was achieved at 450 °C and 2 h−1 over 4Zn/ZS catalyst.