Robust nickel silicate catalysts with high Ni loading for CO₂ methanation

Abstract

CO2 is the main component of greenhouse gases and also an important carbon source. The hydrogenation of CO2 to methane using Ni‐based catalysts can not only alleviate CO2 emissions but also obtain useful fuels. However, Ni‐based catalysts face one major problem of the sintering of Ni nanoparticles in the process of CO2 methanation. Thus, this work has synthesized a series of efficient and robust nickel silicate catalysts (NiPS−X) with different nickel content derived from nickel phyllosilicate by the hydrothermal method. It was found that the Ni loading plays a critical role in the structure and catalytic performance of the NiPS−X catalysts. The catalytic performance gradually increases with the increase of Ni loading. In particular, the highly dispersed NiPS‐1.6 catalyst with a high Ni loading of 34.3 wt% could obtain the CO2 conversion greater than 80%, and the methane selectivity was close to 100% for 48 h at 330 °C and the GHSV of 40,000 mL g−1 h−1. The excellent catalytic property can be assigned to the high dispersion of Ni nanoparticles and the strong interaction between the active component and the carrier, which is derived from a unique layered silicate structure with lots of nickel phyllosilicate and a large number of Lewis acid sites.

Impact of preparation method on nickel speciation and methane dry reforming performance of Ni/SiO2 catalysts

“…Infrared spectrum technology can be used to identify the phase of nickel phyllosilicate in Ni-based catalysts. The absorption vibration peaks at 1,125 cm −1 and 800 cm −1 were attributed to the different vibration modes of Si-O-Si in silica ( Gabrovska et al, 2011 ; Abbas et al, 2018 ; Wang et al, 2018 ; Liao et al, 2021 ). While 1,034 cm −1 and 670 cm −1 were the characteristic absorption peaks of nickel phyllosilicates ( Sivaiah et al, 2010 ; Gong et al, 2012 ), which indicated that the Ni/SiO 2 -AE catalyst contained nickel phyllosilicate, which was beneficial to the dispersion of nickel species.…”

Rational Design of Pt−Pd−Ni Trimetallic Nanocatalysts for Room‐Temperature Benzaldehyde and Styrene Hydrogenation

“…Figure 1 shows the XRD patterns of Pt/Ni/C, Pd/Ni/C and Pt−Pd/Ni/C and Pt−Pd/Ni/C−X catalysts. For the Pt/Ni/C, Pd/Ni/C and Pt−Pd/Ni/C catalysts, the diffraction peaks at 2θ=44.5°, 51.8° and 76.4° belong to Ni(111), (200) and (220) planes, respectively (Figure 1A), [32,33] indicating that the nickel crystallites exist in these catalysts. In the XRD patterns of Pt/Ni/C, there is a weak diffraction peak of PtNi(111) alloy (2θ=42.8°).…”

Heterogeneous Catalysis for CO2 Conversion into Chemicals and Fuels

“…However, catalytically active Ni species are prone to sintering and deactivation because CO 2 methanation is a strongly exothermic reaction. An important strategy for dealing with this issue is to modulate the strong metal-support interaction (SMSI) between Ni NPs and oxides [34][35][36][37][38][39]. Pan and coworkers [37] determined that CO 2 methanation performance was remarkably suppressed and CO was the only product when Ni NPs were supported by conventional anatase (a-TiO 2 ) because of the SMSI-induced formation of a reduced TiO x overlayer around the Ni NPs at high temperature (500 °C).…”