Silica-Decorated NiAl-Layered Double Oxide for Enhanced CO/CO2 Methanation Performance

Abstract

CO/CO2 hydrogenation has attracted much attention as a pathway to achieve carbon neutrality and production of synthetic natural gas (SNG). In this work, two-dimensional NiAl layered double oxide (2D NiAl-LDO) has been successfully decorated by SiO2 nanoparticles derived from SiCl4 and used as CO/CO2 methanation catalysts. The as-obtained H-SiO2-NiAl-LDO exhibited a large specific surface area of 201 m2/g as well as high ratio of metallic Ni0 species and surface adsorption oxygen that were beneficial for low-temperature methanation of CO/CO2. The conversion of CO methanation was 99% at 400 °C, and that of CO2 was 90% at 350 °C. At 250 °C, the CO methanation reached 85% whereas that of CO2 reached 23% at 200 °C. We believe that this provides a simple method to improve the methanation performance of CO and CO2 and a strategy for the modification of other similar catalysts.

Enhanced CO2 Methanation over Ni/Na-HNTs: Effect of Pretreatment with NaOH

“…For the Ni 2p spectrum (Figure 8a), the peaks around 852.5 and 869.7 eV can be attributed to Ni 2p 3/2 and Ni 2p 1/2 orbitals for Ni 0 , respectively, while the peaks around 856.3 eV (Ni 2p 3/2 ) and 873.6 eV (Ni 2p 1/2 ) correspond to Ni 2+ due to the oxidation of metal Ni during the nonin situ test or the unreduced Ni species with stronger metal−support interaction. 51 Importantly, the small and highly dispersed Ni particles are active to be rapidly oxidized when exposed to the air. 52,53 The satellite peaks of Ni 2+ are observed around 862.1 and 880.2 eV.…”