Conversion of methanol to aromatics over ZSM-5/11 intergrowth Zeolites and bimetallic Zn-Cu-ZSM-5/11 and Ga-Ag-ZSM-5/11 catalysts prepared with direct synthesis method

Abstract

Catalytic conversion of methanol to gasoline range hydrocarbons, especially aromatics was carried out in a fixed bed reactor over nano-crystal composite H-ZSM-5/11 zeolite synthesized by hydrothermal method. The metals of Zn, Cu, Ga and Ag as bimetallic Zn-Cu and Ga-Ag with different concentrations (3: 2, 5: 3) and (1:1, 3:2) respectively were selected for loading into the prepared zeolite catalysts. Direct synthesis method was used for incorporating metals. Prepared zeolites were characterized by XRD, SEM, TEM, N 2 adsorption-desorption, ICP-OES, NH 3-TPD and FT-IR. After incorporation of metal species into the zeolites framework, the particles crystalline size was reduced, the intercrystalline porosity was increased, causing the formation of new moderate acid sites. The catalytic results illustrated that the incorporation of metal species enhanced the activity and catalyst stability in MTA reaction. BTX yield in ZSM-5/11 reached up at 23.5% to 30.4% and 25.88% with Zn-Cu-ZSM-5/11(1) and Ga-Ag-ZSM-5/11(1), respectively whereas heavier aromatics production reduced. Also, the comparison of catalysts with different metals content showed that due to improvement in structure and properties, low metal content zeolites have better performance in converting methanol to aromatics.

An efficient green protocol for the synthesis of 1,2,4,5-tetrasubstituted imidazoles in the presence of ZSM-11 zeolite as a reusable catalyst

“…Nevertheless, the absence of the absorption band around 550 cm −1 indicates that the ZSM-11 zeolite type framework is not present in the samples. 31,33–36 The overall absorption bands for the series of zeolite samples were similar to one another. With increased reactions time from 18 to 48 h, we observed that the intensity of the peak at 547 cm −1 was increased due to the percentage of aluminum insertion increases in the zeolite framework.…”

Understanding the Promotional Effect of Silver in Naphtha Reforming over a Ga/ZSM-5 Catalyst to Enhance Liquid Yield

“…A systematic study was done by Hseih et al on dehydroaromatization of ethylene to produce liquid products using Ag/ZSM-5 catalysts. Ag-Ga/ZSM-5 catalysts were synthesized and studied by Juybar et al for the synthesis of aromatic compounds from methanol. Similar studies are reported by Ono et al and He et al .…”

Performance evaluation of a newly developed transition metal-doped HZSM-5 zeolite catalyst for single-step conversion of C1–C3 alcohols to fuel-range hydrocarbons

“…8 In addition, the choice of catalyst substitution method significantly impacts the catalyst's performance and lifespan. 9 Since the introduction of Mobil's methanol-to-gasoline (MTG) process, 10 significant research has been dedicated to exploring the reaction and catalyst deactivation mechanisms involved in the transformation of alcohols for the production of liquid hydrocarbon fuels and light olefins using ZSM-5 zeolite as the catalyst. 11 ZSM-5 zeolites, which possess a uniform pore structure, high surface area, and adjustable acidity, have been extensively utilised in low alcohol-to-hydrocarbon (LATH) reactions, particularly methanol and ethanol.…”

“…8 In addition, the choice of catalyst substitution method significantly impacts the catalyst's performance and lifespan. 9…”

“…9 -C 12 and C 5 -C 8 at 24.4 and 55.60%, while Fe/HZSM-5 and HZSM-5 promote the production of BTX (6.10%) and C 12 + (39.41%) HCs respectively. Compared to methanol feedstock, the performance of ethanol in LATH conversion displays a strong correlation with propanol, as evidenced by their similar percentage selectivity to HC fractions, as shown in…”