Defect-Rich Nickel Nanoparticles Supported on SiC Derived from Silica Fume with Enhanced Catalytic Performance for CO Methanation

• Main Authors: Qi Song, Xingwu Zhai, Feng Yu, Jiangbing Li, Xin Ren, Haiyang Zhang, Mingyuan Zhu, Bin Dai, Guixian Ge, Jinli Zhang
• Format: Article
• Language: English
• Published: MDPI AG 2019-03-01
• Series: Catalysts
• Subjects: defect-rich catalyst; silicon carbide; silica fume; synthetic natural gas; carbon monoxide methanation
• Online Access: https://www.mdpi.com/2073-4344/9/3/295

With the increased demands of environmental protection, recycling/utilization of industrial byproducts has attracted much attention from both industry and academic communities. In this work, silicon carbide (SiC) was successfully synthesized from industrial waste silica fume (SF) during metallic silicon production. Following this, Ni nanoparticles with many defects were supported on the as-obtained SiC by conventional impregnation method. The results showed that defect-rich Ni nanoparticles were dispersed onto the surface of SiC. The as-obtained Ni/SF-SiC exhibited an enhanced metal-support interaction between Ni and SiC. Furthermore, the density functional theory (DFT) calculations showed that the H₂ and CO adsorption energy on Ni vacancy (V_Ni) sites of Ni/SF-SiC were 1.84 and 4.88 eV, respectively. Finally, the Ni/SF-SiC performed high catalytic activity with CO conversion of 99.1% and CH₄ selectivity of 85.7% at 350 °C, 0.1 MPa and a gas hourly space velocity (GHSV) of 18,000 mL·g^−1·h^−1. Moreover, Ni/SF-SiC processed good catalytic stability in the 50 h continuous reaction.