High-Temperature Capture of CO2 on Lithium-Based Sorbents Prepared by a Water-Based Sol-Gel Technique

摘要

A convenient water-based sol-gel technique was used to prepare a highly efficient lithium orthosilicate-based sorbent (Li4SiO4-G) for CO2 capture at high temperature. The Li4SiO4-G sorbent was systematically studied and compared with the Li4SiO4-S sorbent prepared by solid-state reaction. Both sorbents were characterized by X-ray diffraction, scanning electron microscopy, nitrogen adsorption, and thermogravimetry. The CO2 sorption stability was investigated in a dual fixed-bed reactor. Li4SiO4-G exhibited a special Li4SiO4 structure with smaller crystalline nanoparticles, larger surface area, and higher CO2 adsorption properties as compared with Li4SiO4-S. The Li4SiO4-G sorbent also maintained higher capacities during multiple cycles.