Elemental mercury capture on heat-treated activated carbon(TAC) was studied using a laboratory-scale fixed bed reactor.The capability of TAC to perform Hg 0 capture under both N 2 and baseline gas atmospheres was stud...Elemental mercury capture on heat-treated activated carbon(TAC) was studied using a laboratory-scale fixed bed reactor.The capability of TAC to perform Hg 0 capture under both N 2 and baseline gas atmospheres was studied and the effects of common acid gas constituents were evaluated individually to avoid complications resulting from the coexistence of multiple components.The results suggest that surface functional groups(SFGs) on activated carbon(AC) are vital to Hg 0 capture in the absence of acid gases.Meanwhile,the presence of acid gas components coupled with defective graphitic lattices on TAC plays an important role in effective Hg 0 capture.The presence of HCl,NO 2,and NO individually in basic gases markedly enhances Hg 0 capture on TAC due to the heterogeneous oxidation of Hg 0 on acidic sites created on the carbon surface and catalysis by the defective graphitic lattices on TAC.Similarly,the presence of SO 2 improves Hg 0 capture by about 20%.This improvement likely results from the deposition of sulfur groups on the AC surface and oxidation of the elemental mercury by SO 2 due to catalysis on the carbon surface.Furthermore,O 2 exhibits a synergistic effect on Hg 0 oxidation and capture when acid gases are present in the flue gases.展开更多
基金Project supported by the Zhejiang Provincial Natural Science Foundation of China(No.R107532)the Program for New Century Excellent Talents in Universities(No.NCET-08-0490)+2 种基金the Nonprofit Specific Environmental Research Fund(No.200909024)the Fujian Provincial Natural Science Foundation of China(No.2011J01322)the Project of Science and Technology Innovation Platform of Fujian Province(No.2009H2006),China
文摘Elemental mercury capture on heat-treated activated carbon(TAC) was studied using a laboratory-scale fixed bed reactor.The capability of TAC to perform Hg 0 capture under both N 2 and baseline gas atmospheres was studied and the effects of common acid gas constituents were evaluated individually to avoid complications resulting from the coexistence of multiple components.The results suggest that surface functional groups(SFGs) on activated carbon(AC) are vital to Hg 0 capture in the absence of acid gases.Meanwhile,the presence of acid gas components coupled with defective graphitic lattices on TAC plays an important role in effective Hg 0 capture.The presence of HCl,NO 2,and NO individually in basic gases markedly enhances Hg 0 capture on TAC due to the heterogeneous oxidation of Hg 0 on acidic sites created on the carbon surface and catalysis by the defective graphitic lattices on TAC.Similarly,the presence of SO 2 improves Hg 0 capture by about 20%.This improvement likely results from the deposition of sulfur groups on the AC surface and oxidation of the elemental mercury by SO 2 due to catalysis on the carbon surface.Furthermore,O 2 exhibits a synergistic effect on Hg 0 oxidation and capture when acid gases are present in the flue gases.
