| In order to alleviate the odour pollution of oil refining plants at downtime, the study of removal of lab simulated H2S containing malodor gas by adsorption/ catalytic oxidation by activated carbon were progressed.The breakthrough behaviors of ACF and other activated carbons of different origins were investigated in the laboratory experiment. The carbons modified with alkali like KOH, NaOH, Na2CO3 and transitional metal compounds like FeCl3, CuCl2, Cu(NO3)2 were used to adsorb H2S. It was found that carbon samples impregnated by Cu(NO3)2 and HNO3 had very excellent capacity. Influence of activation temperature, bed height, prehumidification, reaction temperature, vacancy velocity, O2, concentration of inlet H2S on removal of H2S was studied. The surface properties were evaluated by means of Boehm titration, surface pH measuration, XRD( X-ray diffraction), XPS( X-ray photoelectron spectroscopy) and element analysis. The reaction product and mechanism was also discussed.The results of lab experiments showed that the capacity of carbons of different forms and origins differ from each other, the smaller the particle size, the better the performance. The wooden-based and fruit-shell activated carbons performed better than the coal-based carbon. The breakthrough capacity of viscose-based activated carbon fiber was notable enlarged by modified with 7%Na2CO3. The breakthrough time of ACF rose to 220 min after heat treatment under 900℃. It was demonstrated that SDA-1 samples had a breakthrough time of 1040 min after impregnated with 2%KI when 300 min before modified. SDA-5 loaded with Cu had such a good performance that the breakthrough time of carbon impregnated with 10%Cu(NO3)2 was 8 times that unmodified. It was found that the breakthrough capacity of SDA-5 modified with 8%Cu(NO3)2 and HNO3 was 13.5 times that hadn't been impregnated in Cu(NO3)2 when the average inlet concentration of H2S was 2277 mg/m3 . It was found that O2 was activated by copper and H2S was oxidized to sulfur, but the reaction stopped when micropores were blocked by sulfur. The effect of Cu(NO3)2 modification was the same with activated carbons of different origins. Copper was fixed in the form of CuO on the activated carbon, and the catalyst deactivated after reacting with H2S and CuS was created. The breakthrough performance of activated carbon impregnated by Cu(NO3)2 decreased after activation at 600℃because the thermal stability reduced after impregnation. The distribution of pore dimension and surface chemistry had changed after modified with Cu(NO3)2 and HNO3, and sulfur and oxides of sulfur formatted. It was showed that the breakthrough time augmented as the bed height rose, but reduced when vacancy velocity and inlet H2S concentration increased. SDA-5 sample had a longest breakthrough time as the volume of water added to carbon was 1.0mL/g. The breakthrough time of modified carbons in inlet gas of H2S + N2 was about 1/10 that inlet gas containing O2.
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