Integrated CO2 capture and In-Situ methanation by efficient dual functional Li4SiO4@Ni/CeO2

Abstract

Listen

Translate article

Integrated carbon capture and utilization by methanation (ICCU-methanation) is an emerging concept in reducing CO2 emissions and storing H2 simultaneously. One key of the technology is the development of dual functional materials (DFMs) that can efficiently capture CO2 and then catalyze it. Herein, we propose the construction of DFM using Li4SiO4 with superior CO2 adsorption/desorption features as sorbent and catalyst carrier, CeO2 as catalyst promoter and isolator, and Ni as catalytic metal, and comprehensively evaluate its characteristics and performance in ICCU-methanation. Results show that the DFM developed possess a high and stable CO2 capacity of 5.4 mmol·gDFM-1, 96 % CO2 conversion and 96 % CH4 selectivity under both the ideal CO2 capturing atmosphere and the realistic flue gas containing 10 vol% steam and 8 vol% O2. Moreover, rapid CO2 dissociation from the DFM is observed at a temperature lower to 560 °C due to the reaction of H* dissociated by catalyst with carbonate to form formate, which further decomposes to release CO.