Scholarlink

<p>Methanation has been well-known as an effective way to convert CO<sub>2</sub> into synthetic fuel gas, CH<sub>4</sub>. In this paper, the optimum Ni content and heat treatment conditions to obtain the highest catalytic activity of Ni/SiO<sub>2</sub> catalysts in CO<sub>2</sub> methanation were investigated and selected. To further improve the performance of the Ni/SiO<sub>2</sub> catalyst, herein, a series of Ni-Ru/SiO<sub>2</sub> catalysts (with Ru content varying within 0.1–0.3&#xa0;wt.%) were facilely prepared and studied. The monometallic Ni/SiO<sub>2</sub> and bimetallic Ni-Ru/SiO<sub>2</sub> samples were prepared by impregnation method. The catalysts were characterized with physicochemical properties by various modern techniques like X–ray diffraction, hydrogen temperature–programmed reduction, CO<sub>2</sub> temperature–programmed desorption, scanning electron microscopy, transmission electron microscopy, high–resolution transmission electron microscopy, and energy-dispersive spectroscopy. The catalysts were also assessed with activity in the CO<sub>2</sub> methanation at atmospheric pressure and in the reaction temperature range of 250–400&#xa0;°C with H<sub>2</sub>/CO<sub>2</sub> molar ratio of 4/1. The results showed that the presence of Ru could improve Ni dispersion and create Ni-Ru alloy due to strong Ni-Ru interaction, leading to smaller crystallite size of Ni (10.7–12.6&#xa0;nm) and higher reducibility. The addition of Ru did not increase the basicity of the catalyst, but it did increase the proportion of medium basic sites, which in turn led to an increase in catalytic activity. The highest catalytic activity corresponding to a T<sub>50%</sub> value of 313&#xa0;°C and achieved equilibrium CO<sub>2</sub> conversion (80%) at as low temperatures as 350&#xa0;°C along with methane selectivity of 100%, was recorded on 20Ni0.2Ru/SiO<sub>2</sub> catalyst, which possessed a high specific surface area of 361.6&#xa0;m<sup>2</sup>/g, the highest reduction degree of 88.6%, and highest medium basic site ratio of 68%. Despite the lower Ru content, the activation effect of the 20Ni0.2Ru/SiO<sub>2</sub> catalyst in this study was equivalent to that of the referenced Ru-modified catalysts with significantly higher Ru content, creating a cost-effective advantage in large-scale applications. 20Ni0.2Ru/SiO<sub>2</sub> catalyst also exhibited high stability due to structural stability, high sintering resistance, and low coke deposition.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Ru-Promoted Ni/Mesoporous Silica Catalyst for Production of Synthetic Fuel Gas (SFG) from CO2

  • 期刊论文

  • 发表日期：

    2025年9月15日

查看全文
  • Anh Huy Tran,
  • Ba Long Do,
  • Hong Phuong Phan,
  • Phung Anh Nguyen,
  • Thi Thuy Van Nguyen,
  • Cam Anh Ha,
  • Tien Cuong Hoang,
  • Tri Nguyen,
  • Luu Cam Loc

摘要

Methanation has been well-known as an effective way to convert CO2 into synthetic fuel gas, CH4. In this paper, the optimum Ni content and heat treatment conditions to obtain the highest catalytic activity of Ni/SiO2 catalysts in CO2 methanation were investigated and selected. To further improve the performance of the Ni/SiO2 catalyst, herein, a series of Ni-Ru/SiO2 catalysts (with Ru content varying within 0.1–0.3 wt.%) were facilely prepared and studied. The monometallic Ni/SiO2 and bimetallic Ni-Ru/SiO2 samples were prepared by impregnation method. The catalysts were characterized with physicochemical properties by various modern techniques like X–ray diffraction, hydrogen temperature–programmed reduction, CO2 temperature–programmed desorption, scanning electron microscopy, transmission electron microscopy, high–resolution transmission electron microscopy, and energy-dispersive spectroscopy. The catalysts were also assessed with activity in the CO2 methanation at atmospheric pressure and in the reaction temperature range of 250–400 °C with H2/CO2 molar ratio of 4/1. The results showed that the presence of Ru could improve Ni dispersion and create Ni-Ru alloy due to strong Ni-Ru interaction, leading to smaller crystallite size of Ni (10.7–12.6 nm) and higher reducibility. The addition of Ru did not increase the basicity of the catalyst, but it did increase the proportion of medium basic sites, which in turn led to an increase in catalytic activity. The highest catalytic activity corresponding to a T50% value of 313 °C and achieved equilibrium CO2 conversion (80%) at as low temperatures as 350 °C along with methane selectivity of 100%, was recorded on 20Ni0.2Ru/SiO2 catalyst, which possessed a high specific surface area of 361.6 m2/g, the highest reduction degree of 88.6%, and highest medium basic site ratio of 68%. Despite the lower Ru content, the activation effect of the 20Ni0.2Ru/SiO2 catalyst in this study was equivalent to that of the referenced Ru-modified catalysts with significantly higher Ru content, creating a cost-effective advantage in large-scale applications. 20Ni0.2Ru/SiO2 catalyst also exhibited high stability due to structural stability, high sintering resistance, and low coke deposition.