Sol-gel synthesis and gas adsorption properties of CuCl modified mesoporous alumina

Cuprous chloride (CuCl) modified unsupported γ-alumina membranes and adsorbent granules were synthesized by sol-gel processing followed by wet-impregnation of CuCl. The CuCl coated γ-alumina remains mesoporous with a uniform pore size distribution and a large surface area. The mesoporous alumina granules, prepared by a sol-gel oil-drop process, exhibit excellent mechanical strength and attrition resistance. The CuCl modified γ-alumina preferentially adsorbs ethylene and carbon monoxide, with a saturated adsorption capacity of 0.67 and 0.78 mmol/g, respectively. Both equilibrium capacity and kinetic rate for adsorption of ethylene and carbon monoxide on the CuCl modified γ-alumina are much larger than those for ethane and carbon dioxide. These results indicate the potential use of the sol-gel derived CuCl modified γ-alumina for separation of ethylene or carbon monoxide from its gas mixture containing ethane or carbon dioxide.