Al distribution and catalytic performance of ZSM-5 zeolites synthesized with various alcohols

- ZSM-5 was synthesized from the synthetic gels containing various alcohols.
- The impact of the alcohols on the Al distribution was investigated.
- Al distribution was considered by constrain index and Co2+ exchange properties.
- The impact of the Al distribution on the catalytic properties was clarified.

The distribution of Al atoms in ZSM-5 has been recognized as an important factor in catalytic activity. Here, ZSM-5 zeolites were synthesized from synthetic gels containing various alcohols, including straight- and branched-chains alcohols. The effect of the alcohols in the synthetic gel on the Al distribution in the MFI framework was investigated based on 27Al MAS NMR, Co(II) ion UV−vis DRS, and constraint index value. Thus synthesized ZSM-5 zeolites were applied to catalysts for the cracking of n-hexane and the methanol-to-olefins (MTO) reactions in order to investigate the impact of the Al distribution on the catalytic properties. A unique Al distribution in the MFI framework was achieved by the use of trimethylolethane (TME) in combination with Na cations, and thus-prepared ZSM-5 catalyst showed a long catalytic life for both the cracking of n-hexane and the MTO reaction.

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