Effect of surface modification of Fe/g-C3N4 catalyst on the product distribution in CO hydrogenation

被引：2

作者：

Sun Y. ^{[1
]}

Gao X. ^{[1
]}

Ma Q. ^{[1
]}

Fan S. ^{[1
]}

Zhao T. ^{[1
]}

Zhang J. ^{[1
]}

机构：

[1] State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry & Chemical Engineering, Ningxia University, Yinchuan

来源：

Ranliao Huaxue Xuebao/Journal of Fuel Chemistry and Technology | 2024年 / 52卷 / 01期

基金：

中国国家自然科学基金;

关键词：

CO hydrogenation; Fe/g-C[!sub]3[!/sub]N[!sub]4[!/sub] catalyst; product distribution; surface modification;

D O I：

10.1016/S1872-5813(23)60378-0

中图分类号：

学科分类号：

摘要：

Carbon nitride (g-C3N4) prepared using thermal condensation of urea was pretreated by H2O2/NH3·H2O and used as support to obtain Fe/g-C3N4 catalyst via impregnation method. The catalytic performance of the catalysts both before and after modification was investigated in CO hydrogenation. Combining detailed characterizations, such as XRD, SEM, TEM, FT-IR, TG, CO2-TPD, CO-TPD, H2-TPR, contact angle measurement, and N2 physical adsorption and desorption, we investigated the effects of surface pretreatment on the texture properties of Fe/g-C3N4 catalysts and the product distribution of CO hydrogenation. The results demonstrate that various pretreatment techniques have significant influences on the textural properties and catalytic performance of the catalysts. The prepared g-C3N4 with a typical honeycomb structure has strong interaction with highly dispersed Fe. Both before and after modification, the materials are hydrophilic, and the hydrophilicity is increased after treatment with H2O2 and NH3·H2O. Treatment with H2O2 enhances surface hydroxyl groups. NH3·H2O treatment improves surface amino groups, promotes CO adsorption, and facilitates the formation of Fe(NCN) phase. The surface basicity of all pretreated catalysts is enhanced. The water gas shift (WGS) reaction activity of the two-step modified catalyst Fe/AM-g-C3N4 was lower, and the CO2 selectivity in CO hydrogenation was reduced to 11.61%. Due to the enhanced basicity of Fe/AM-g-C3N4, the secondary hydrogenation ability of olefins was inhibited to obtain higher olefin selectivity with C=2 − C=4 s of 32.37% and an O/P value of 3.23. © 2024 Science Press. All rights reserved.

引用

页码：19 / 28

页数：9

共 40 条

[1]

FUJIMORI S, INOUE S, Carbon monoxide in main-group chemistry[J], J Am Chem Soc, 5, 144, pp. 2034-2050, (2022)

[2]

LIU Sai-sai, YAO Jin-gang, CHEN Guan-yi, Et al., One-step catalyst for the preparation of light olefins and liquid fuels from syngas[J], J Fuel Chem Technol, 51, 1, pp. 34-51, (2023)

[3]

CHENG K, GU B, LIU X L, Et al., Direct and highly selective conversion of synthesis gas into lower olefins: Design of a bifunctional catalyst combining methanol synthesis and carbon-carbon coupling[J], Angew Chem Int Ed, 55, 15, pp. 4725-4278, (2016)

[4]

JIAO F, LI J J, PAN X L, Et al., Selective conversion of syngas to light olefins[J], Science, 6277, 351, pp. 1065-1068, (2016)

[5]

JIAO F, PAN X L, GONG K, Et al., Shape-selective zeolites promote ethylene formation from syngas via a ketene intermediate[J], Angew Chem Int Ed, 57, 17, pp. 4692-4696, (2018)

[6]

ZHANG P P, TAN L, YANG G H, Et al., One-pass selective conversion of syngas to paraxylene[J], Chem Sci, 8, 12, pp. 7941-7946, (2017)

[7]

ZHAO B, ZHAI P, WANG P F, Et al., Direct transformation of syngas to aromatics over Na-Zn-Fe5C2 and hierarchical HZSM-5 tandem catalysts[J], Chem, 3, 2, (2017)

[8]

YU X F, ZHANG J L, WANG X, Et al., Fischer-Tropsch synthesis over methyl modified Fe2O3@SiO2 catalysts with low CO2 selectivity[J], Appl Catal B: Environ, 232, pp. 420-428, (2018)

[9]

XU Y F, LI X Y, GAO J H, Et al., A hydrophobic FeMn@Si catalyst increases olefins from syngas by suppressing C1 by-products[J], Science, 371, 6529, pp. 610-613, (2021)

[10]

MA Long, ZHANG Yu-xi, GAO Xin-hua, Et al., Preparation of Fe3O4@PI and its catalytic performance in Fischer-Tropsch synthesis[J], J Fuel Chem Technol, 48, 7, pp. 813-820, (2020)

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