| Methanol to aromatics process (MTA) as a non-oil route plays an important role in the production of high-quality aromatics. MTA is a sustainable process because methanol can be easily produced from coal, natural gas and biomass. Therefore, methanol is an important intermediate linking petrochemical and coal chemistry industry, especially in coal to aromatics process. MTA can provide prosperous application for coal and relieve the stress of the shortage of aromatics resource, which results in MTA have strategic importance in national energy security.In this study, thermodynamic analysis of MTH system had been carried out firstly, and then the effect of reaction conditions was investigated over HZSM-5catalyst. Finally, zeolites and supports for catalysts were considered respectively. The main conclusions are as following:1. The thermodynamic results indicated that the process of MTH was an exothermic and irreversible process. All reactions involved in MTH could occur spontaneously. At higher temperature and lower pressure, it is favorable for the production of aromatics.2. Olefins could almost completely changed into aromatics and alkanes when MTH process reached thermodynamic equilibrium. According to the requirement of different products, the reaction conditions and catalysts should be taken into consideration.3. To obtain higher aromatics selectivity and long lifetime of catalyst, the optimum conditions for MTA were:400～450℃for reaction temperature,0.1-0.5MPa for reaction pressure,1～2h-1for methanol space velocity and methanol feed alone.4. Nano-sized HZSM-5with low ratio SiO2/Al2O3was superior to other zeolite for MTA process due to its better activity and stronger tolerance to coke.5. The support with proper structure and proportion in catalyst could contribute to improving porosity of catalyst and disperse the active sites to enhance the stability of catalyst. The results showed that proper surface area and20～40wt%proportion of support in catalyst were favorable to MTA. |
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