Abstract:
In view of the characteristics of low concentration and discontinuous emission of VOCs from industrial furnaces in small enterprises,the commercial activated carbon was chosen as adsorption material and the home-made Pd-Ce/Al_2O_3 binary catalyst was used as catalytic material to study the integrated purification technology of VOCs waste gas from industrial furnaces. BET,SEM and TG were used to characterize and test the adsorption performance of the activated carbon. Toluene was chosen as target pollutants to investigate the effects of the desorption time,the flue gas dilution ratio,the catalytic temperature and the flue gas cycle times on the purification performance of toluene exhaust gas. The results show that the adsorbed toluene in the active carbon can be removed with the thermal generation at 100 ℃ for 1 hour,and toluene be completely oxidized when the catalytic temperature is 320 ℃ .After 10-15 cycles of operation,the activated carbon material can be completely regenerated at 100 ℃ for 6 h,which has the best economic benefit. The characterization results show that after many times of thermal regeneration,the pore channel of activated carbon partially collapses,the specific surface area decreases from889 m~2/g to 688 m~2/g,and the pore volume decreases from 0.50 mL/g to 0.37 mL/g. But the pore diameter is still about 2.2 nm,which is consistent with the reduction of wrinkles on the surface of activated carbon observed by SEM,indicating that the pore of activated carbon collapses to a certain extent after thermal regeneration,but can maintained the mesoporous characteristics. The weight loss curve of activated carbon after regeneration in TG curve is slightly lower than that of fresh activated carbon,which further proves that multiple thermal regeneration has a certain destructive effect on the pore structure of activated carbon.