Enhanced Performance of Methyl Ester to Renewable Aromatics via Thermocatalytic Conversion over Metal‐Modified HZSM‐5 Zeolites: An Experimental Study

• Published in: ChemistrySelect (Weinheim) 2018-12, Vol.3 (47), p.13338-13344
• Main Author: Bayat, Ahmad
• Format: Article
• Language: English
• Subjects: HZSM-5; Methyl Ester; Molybdenum; Renewable Aromatics; Zeolite
• ISSN: 2365-6549; 2365-6549
• DOI: 10.1002/slct.201802962

The aim of this research was to study the effect of metal species on the conversion of canola oil methyl esters to renewable aromatics over HZSM‐5 zeolite. The Mo modified HZSM‐5 catalysts were prepared by incipient wetness impregnation method and their application in the conversion of methyl esters to aromatics was investigated. Various techniques were employed to characterize the catalysts comprising X‐ray diffraction (XRD), transmission electron microscopy (TEM), N2 adsorption‐desorption and ammonia temperature‐programmed desorption (NH3‐TPD). The aromatization reaction was conducted under atmospheric pressure. The influence of operating temperature and Weight Hourly Space Velocity (WHSV) on the aromatics yields were studied. The reactor temperature and space velocity were adjusted at 400/450 °C and 2/4 hr−1, respectively. The major constituents of the product were organic liquid product (OLP), gases and water. The aromatic content of the OLP was determined by Gas Chromatography (GC) analysis. The major aromatic compound was toluene followed by para‐meta xylenes. An increase in aromatic yield was observed with the addition of Mo species into HZSM‐5 catalyst at lower space velocities. The maximum aromatic yield of 38.9% was obtained over MZ2 catalyst at lower space velocity and higher temperature. The parent and Mo modified HZSM‐5 catalysts retained the catalytic activity for up to 6 reaction‐regeneration cycles which encourages their potential for industrial applications. Production of renewable aromatics from triacylglycerol was conducted through a two‐step process. Primarily, the canola oil methyl esters were prepared by conventional transesterification method. Thereafter, renewable aromatics were produced via catalytic conversion of methyl esters over molybdenum modified HZSM catalyst. The main aromatic products were toluene and xylenes. Maximum aromatic yields were obtained as 38.9% over the HZSM‐5 catalyst with higher molybdenum content. The parent and metal modified HZSM‐5 catalysts represented outstanding recyclability.