Significant enhancement in From granular to super-fine catalytic ozonation efficacy： powdered activated carbon  

作　　者：Tianyi Chen Wancong Gul Gen Li Qiuying Wang Peng Liangt Xiaoyuan Zhang l Xia Huang 

机构地区：[1]State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China [2]Department of Urban Construction, Wuhan University of Science and Technology, Wuhan 400065, China

出　　处：《Frontiers of Environmental Science & Engineering》2018年第1期85-95,共11页环境科学与工程前沿（英文）

摘　　要：In this study, super-fine powdered activated carbon （SPAC） has been proposed and investigated as a novel catalyst for the catalytic ozonation of oxalate for the first time. SPAC was prepared from commercial granular activated carbon （GAC） by ball milling. SPAC exhibited high external surface area with a far greater member of meso- and macropores （563% increase in volume）. The catalytic perfon,nances of activated carbons （ACs） of 8 sizes were compared and the rate constant for pseudo first-order total organic carbon removal increased from 0.012 mint to 0.568 min l （47-fold increase） with the decrease in size of AC from 20 to 40 mesh （863 ~tm） to SPAC （-1.0 tim）. Furthermore, the diffusion resistance of SPAC decreased 17-fold compared with GAC. The ratio ofoxalate degradation by surface reaction increased by 57%. The rate of transformation of ozone to radicals by SPAC was 330 times that of GAC. The results suggest that a series of changes stimulated by ball milling, including a larger ratio of external surface area, less diffusion resistance, significant surface reaction and potential oxidized surface all contributed to enhancing catalytic ozonation performance. This study demonstrated that SPAC is a simple and effective catalyst fur enhancing catalytic ozonation efficacy.In this study, super-fine powdered activated carbon （SPAC） has been proposed and investigated as a novel catalyst for the catalytic ozonation of oxalate for the first time. SPAC was prepared from commercial granular activated carbon （GAC） by ball milling. SPAC exhibited high external surface area with a far greater member of meso- and macropores （563% increase in volume）. The catalytic perfon,nances of activated carbons （ACs） of 8 sizes were compared and the rate constant for pseudo first-order total organic carbon removal increased from 0.012 mint to 0.568 min l （47-fold increase） with the decrease in size of AC from 20 to 40 mesh （863 ~tm） to SPAC （-1.0 tim）. Furthermore, the diffusion resistance of SPAC decreased 17-fold compared with GAC. The ratio ofoxalate degradation by surface reaction increased by 57%. The rate of transformation of ozone to radicals by SPAC was 330 times that of GAC. The results suggest that a series of changes stimulated by ball milling, including a larger ratio of external surface area, less diffusion resistance, significant surface reaction and potential oxidized surface all contributed to enhancing catalytic ozonation performance. This study demonstrated that SPAC is a simple and effective catalyst fur enhancing catalytic ozonation efficacy.

关 键 词：Super-fine activated carbonCatalytic ozonationExternal surface areaSurface reactionHydroxyl radical 

分 类 号：O643.36[理学—物理化学] Q26[理学—化学]