Enhanced CO2 absorption kinetics in lithium silicate platelets synthesized by a sol–gel approach

Journal of Materials Chemistry A Pub Date: 2014-06-10 DOI: 10.1039/C4TA01976H

Abstract

Platelet-shaped lithium orthosilicate particles synthesized by a sol–gel approach employing the precursors lithium nitrate and colloidal silica displayed enhanced absorption kinetics for CO2 compared to the powders prepared by a solid-state reaction process involving Li2CO3 and silica. The sol–gel samples showed a CO2 absorption capacity of 350 mg g?1 at an absorption rate of 22.5 mg g?1 min?1, a value 70% higher than the rate of 13.2 mg g?1 min?1 measured with the solid-state samples under similar conditions. The higher sorption kinetics of CO2 by the sol–gel derived lithium orthosilicate could be attributed to the unique platelet morphology of the particles, which have a very small thickness. A porous carbon mesh coated with the sol–gel based particles exhibited CO2 absorption capacity of 150 mg g?1 at an absorption rate of 37.5 mg g?1 min?1. This supported absorbent also showed stable absorption and desorption performance for the 8 cycles examined in this study. The excellent absorption characteristics of the sol–gel prepared powders, more specifically the coated strips, provide a successful pathway for the commercialisation of these materials.

Graphical abstract: Enhanced CO2 absorption kinetics in lithium silicate platelets synthesized by a sol–gel approach
Recommended Literature