Catalytic Research Of Methanol To Aromatics

MTA reaction was studied in this paper, including thermomechanical analysis, preparation of catalysts, performance test of the catalysts and optimization of technical conditions. In addition, SEM, BET, XRD and NH3-TPD were employed to investigate structural and acidity characteristics of the catalysts. Connection between physico-chemical property and catalytic performance was also researched. Finally, stability test was taken.Thermomechanical analysis showed that MTA reaction released intense heat, and it was studied that lmol methanol could release40kJ heat in the case of a complete transformation. Composition of the products was influenced by the reaction temperature. High temperature was in favor of aromatics generation while low temperature was to the benefit of alkanes.Performance test showed that HZSM-5was the most ideal catalyst for MTA reaction and suitable Si/Al of the zeolite was15-50. The ratio between strong acid and weak acid was enhanced greatly with Zn loading HZSM-5, whose catalytic performance increased obviously but suffered a bad stability. However, the yield of aromatics and stability of the catalyst were both enhanced with Zn and M loading together, possessing an aromatics yield as high as56.73%. The BET specific surface area and total pore volume were improved after acid-base system was used to treat HZSM-5to prepare hierarchical HZSM-5, whose stability was also enhanced obviously. What’s more, the lifetime of the catalyst was increased from50h to150h after parental HZSM-5was treated with some kind of condition.Technical conditions study showed that low pressure, low WHSV, high temperature and hydrogen pretreatment were beneficial to aromatics generation.