Selective capture of CO2 by poly(amido amine) dendrimer-loaded organoclays

Abstract

Clay loaded poly(amido amine) dendrimers were explored for capture and storage of CO₂. The loading of dendrimer was promotive in the order of laponite > hydrotalcite > sericite and depended on the surface area of the clays. The CO₂ adsorption on organoclays of laponite and sericite with cationic dendrimer increased with the amount of loaded dendrimer. While CO₂ on pristine laponite was completely released in the desorption process, CO₂ on organo laponite remained in part after the desorption equilibrium. Since the removal of CO₂ from organo laponite was almost comparable to that from pristine clay, it can be mentioned that CO₂ adsorbed on the binding site of laponite is almost desorbed but CO₂ on the binding site of dendrimer is conserved in organoclay. In contrast, in the case of the CO₂ adsorption on the organoclay of hydrotalcite with an anionic dendrimer, the diminution of adsorption sites on hydrotalcite owing to the occupation by dendrimer was observed. It can be mentioned that the cation-exchanged organo laponite loaded amine-terminated dendrimer is a valuable solid adsorbent with a highly selective capture capacity for CO₂.