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Highly Efficient Production of Benzene-Free Aromatics from Methanol over Low-Si/Al-Ratio Alkali-Modified Fe/Zn/HZSM-5.

ABSTRACT: Herein, the methanol conversion to aromatic hydrocarbons was studied over a new family of mesoporous low-silica HZSM-5 (Si/Al = 11) catalysts in a fixed-bed tubular reactor under ambient pressure at 375 °C, feeding with weight hourly space velocity of 2 h^-1. The catalysts were prepared in the absence and presence of Zn and Fe in both alkaline and neutral aqueous solutions, characterized by using X-ray diffraction, X-ray fluorescence, temperature programmed desorption of ammonia, N₂ adsorption/desorption, thermogravimetric analysis, Fourier-transform infrared, transmission electron microscopy (TEM), field emission scanning electron microscopy and FE-SEM/energy dispersive X-ray spectroscopy techniques. The [0.2Fe,0.3Zn]-alk-HZSM-5 catalyst exhibited novel selectivity for aromatics (>86 wt %), specifically for m and p-xylenes (44.7 wt %) alongside 0.1 wt % for benzene.

SUBMITTER: Ghanbari B

PROVIDER: S-EPMC6644331 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Highly Efficient Production of Benzene-Free Aromatics from Methanol over Low-Si/Al-Ratio Alkali-Modified Fe/Zn/HZSM-5.

Ghanbari Bahram B Zangeneh Fatemeh Kazemi FK Rizi Zahra Taheri ZT Aghaei Erfan E

ACS omega 20181231 12

Herein, the methanol conversion to aromatic hydrocarbons was studied over a new family of mesoporous low-silica HZSM-5 (Si/Al = 11) catalysts in a fixed-bed tubular reactor under ambient pressure at 375 °C, feeding with weight hourly space velocity of 2 h<sup>-1</sup>. The catalysts were prepared in the absence and presence of Zn and Fe in both alkaline and neutral aqueous solutions, characterized by using X-ray diffraction, X-ray fluorescence, temperature programmed desorption of ammonia, N<sub ...[more]

PMID: 31458445

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