活性炭的表面处理对二苯并噻吩催化氧化脱除的影响

An activated carbon of wood origin was treated by a diluted sulfuric acid solution of KMnO4 (KS), concentrated nitric acid (CN) and thermal oxidation at 350℃ (HT). The structural properties and surface chemistry of the samples with different treatments were characterized by using sorption of nitrogen and Boehm titration, respectively. Oxidative removal of dibenzothiopene (DBT) with hydrogen peroxide catalyzed by the activated carbons was studied. The results showed that the oxidative removal of DBT is dependent on carbon surface properties. The effect of carbon surface properties on the adsorption of DBT is different from its effect on the oxidative removal of DBT; the increase of total acidic groups is favorable for DBT adsorption. The increase of the amount of carbonyl groups is obviously favorable for the oxidative removal of DBT due to a factor: surface carbonyl groups can accelerate hydrogen peroxide to produce hydroxyl radicals. The catalytic performance of activated carbon for the oxidative removal of DBT is improved significantly with the treatment of thermal oxidation at 350℃; the sulfur content in the noctane solution is decreased from 0.556g·L-1 to 0.009g·L-1.