Periodic mesoporous organosilicas functionalized with a wide variety of amines for CO2 adsorption

Abstract

The adsorption of CO₂ on amine modified periodic mesoporous organosilicas (PMOs) has been investigated. An ethenylene-bridged PMO is modified with a wide range of diamines and polyamines. A variety of dangling N-containing functionalities, i.e., diaminobutane, diaminohexane, diaminododecane, diethylenetriamine and tetraethylenepentamine, as nucleophiles in a substitution reaction is used. The CO₂ adsorption capacity of these materials is probed and compared with amine functionalized SBA-15 material, in an effort to reach the maximal CO₂/N ratio of 0.5 when using dry conditions in a chemisorption process. The materials showed good CO₂ adsorption behaviour and this maximum amine efficiency value has been approximated by the PMO material modified with diaminododecane.