EFFECT OF MODIFIED ZSM-5 ZEOLITE WITH DIFFERENT METALS ON n-PENTANE AND METHANOL CO-AROMATIZATION

Abstract

Abstract: ZSM-5 molecular sieve were modified with different metals by impregnation method to obtain zeolite catalysts with different metals loads. The catalysts were characterized by XRD, Py-IR techniques. The aromatization performance of the samples in n-pentane and methanol co-aromatization was investigated in a fixed-bed micro-reactor. The results showed that Zn, Ag, Ni, and Cu, modified catalysts improved the aromatic selectivity, among which the Ni and Ag modified catalysts showed the better aromatization effects. With the optimal metal load, the conversions of n-pentane and methanol were 100%; the aromatic selectivity was up to 37.69%. The catalysts modified with Zn, Ag, Ni, and Cu showed the formation of new L acid, decrease of B acid and increase of L acid, which promoted the dehydrogenation reaction, forming more aromatics from olefin intermediates and improving the aromatic selectivity. The content of different aromatic components in the products increased with the modification of different metals

Key words: ZSM-5 molacular sieve, metal, zinc, silver, copper, n-pentane, methanol, co-aromatization

CLC Number:

References

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