Authors: Shouxin Liu Rui Wang
Publish Date: 2010/02/06
Volume: 18, Issue: 1, Pages: 99-106
Abstract
To enhance nitrobenzene removal from aqueous solution commercial activated carbon AC was modified by oxidation with HNO3 followed by heat treatment in a nitrogen atmosphere The modification process introduced oxygencontaining functional groups and changed the charge properties of the AC surface The effects of surface chemical properties and pore structure on the adsorption of nitrobenzene by the AC were investigated through kinetics and equilibrium isotherms HNO3 oxidation modified the surface chemical properties and increased the number of acidic oxygencontaining surface groups but had an almost negligible effect on the pore structure Subsequent heat treatment caused decomposition of oxygencontaining functional groups on the AC surface increased the pH point of zero charge pHPZC and increased the number of mesopores The maximum adsorption capacity achieved by the modified AC was 144353 mg g−1 333 times of that unmodified AC HNO3 oxidation combined with heat treatment was an effective method for the preparation of AC with high nitrobenzene adsorption capacity and fast adsorption kinetics An appropriate pHPZC amount of surface oxygen groups and the presence of welldeveloped mesopores together with micropores were the main reasons for the high nitrobenzene adsorption capacity of the modified AC
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