Solid Amine Sorbents For Co<Inf>2</Inf> Capture By Chemical Adsorption: A Review

Abstract

Amines are well-known for their reversible reactions with CO2, which make them ideal for CO2capture from several gas streams, includingflue gas. In this respect, selective CO2absorption byaqueous alkanolamines is the most mature technology but the process is energy intensive and hasalso corrosion problems. Both disadvantages can be diminished to a certain extent by chemicaladsorption of CO2selectively. The most important element of the chemical adsorption of CO2in-volves the design and development of a suitable adsorbent which consist of a porous support ontowhich an amine is attached or immobilized. Such an adsorbent is often called as solid aminesorbent. This review covers solid amine-based studies which are developed and published in recentyears. First, the review examines several different types of porous support materials, namely, threemesoporous silica (MCM-41, SBA-15 and KIT-6) and two polymeric supports (PMMA and PS) for CO2adsorption. Emphasis is given to the synthesis, modifications and characterizations -such as BETand PXRD data-of them. Amination of these supports to obtain a solid amine sorbent throughimpregnation or grafting is reviewed comparatively. Focus is given to the adsorption mechanisms,material characteristics, and synthesis methods which are discussed in detail. Significant amount oforiginal data are also presented which makes this review unique. Finally, relevant CO2adsorption(or equilibrium) capacity data, and cyclic adsorption/desorption performance and stability ofimportant classes of solid amine sorbents are critically reviewed. These include severa PEI or TEPAimpregnated adsorbents and APTES-grafted systems.