Templated synthesis of mesoporous aluminas by graft copolymer and their C[O.sub.2] adsorption capacities

Mesoporous aluminas were synthesized via a sol-gel process by templating an amphiphilic graft copolymer, PVC-g-POEM, consisting of a poly(vinyl chloride) (PVC) backbone and poly(oxyethylene methacrylate) (POEM) side chains. The mesoporous structures of aluminas with large surface areas were confirmed by X-ray diffraction, transmission electron microscopy, and nitrogen adsorption/desorption analysis. Aluminas synthesized with PVC-g-POEM graft copolymer exhibited higher C[O.sub.2] adsorption capacities (0.7 mol C[O.sub.2]/kg sorbent) than aluminas synthesized without graft copolymer (0.6 mol C[O.sub.2]/kg sorbent). The adsorption capacity of alumina strongly depends on its structure and calcination temperature; amorphous (400°C) > γ phase (800°C) > α phase (1000°C).