A novel heterogeneous catalytic ozonation process in water treatment was studied, with a copper-loaded activated carbon （Cu/AC） that was prepared by an incipient wetness impregnation method at low temperature and te...A novel heterogeneous catalytic ozonation process in water treatment was studied, with a copper-loaded activated carbon （Cu/AC） that was prepared by an incipient wetness impregnation method at low temperature and tested as a catalyst in the ozonation of phenol and oxalic acid. Cu/AC was characterized using XRD, BET and SEM techniques. Compared with ozonation alone, the presence of Cu/AC in the ozonation processes significantly improves the degradation of phenol or oxalic acid. With the introduction of the hydroxyl radical scavenger, i.e., turt-butanol alcohol （t-BuOH）, the degradation efficiency of both phenol and oxalic acid in the Cu/AC catalyzed ozonation process decreases by 22% at 30 min. This indicates that Cu/AC accelerates ozone decomposition into certain concentration of hydroxyl radicals. The amount of Cu（II ） produced during the reaction of Cu/AC-catalyzed ozonation of phenol or oxalic acid is very small, which shows that the two processes are both heterogeneous catalytic ozonation reactions.展开更多
A novel type of metal oxide/activated carbon catalyst was prepared by sol-gel method for the hydrolysis of carbonyl sulfide （COS）. The influences of the calcination temperature, additive content （2.5%-10.0% Fe2O3, ...A novel type of metal oxide/activated carbon catalyst was prepared by sol-gel method for the hydrolysis of carbonyl sulfide （COS）. The influences of the calcination temperature, additive content （2.5%-10.0% Fe2O3, mass fraction） and the basic density of the activation process were thoroughly investigated. The surface of catalysts was characterized by Boehm titration. The products were characterized by scanning electron microscopy （SEM）, X-ray diffractometry （XRD） and X-ray photoelectron spectroscopy （XPS）. The results show that catalysts with 2.5%-5.0% Fe2O3 after calcining at 500 ℃ have superior activity. The conversion rate of COS increases with increasing the relative density of basic capacity loaded onto activated carbon（AC）, and the activity follows the order： KOH〉Na2CO3 〉NaHCO3. Boehm titration data clearly show that the total acidity increases （from 0.06 to 0.48 mmol/g） and the basic groups decrease （from 0.78 to 0.56 mmol/g） after COS hydrolysis and H2S adsorption. The XPS results show that the product of HzS may be absorbed by the interaction with metal compounds and 02 to form sulfate （171.28 eV） and element sulfur （164.44 eV）, which lead to catalysts poisoning.展开更多
基金Project(40973074) supported by the National Natural Science Foundation of China
文摘A novel heterogeneous catalytic ozonation process in water treatment was studied, with a copper-loaded activated carbon （Cu/AC） that was prepared by an incipient wetness impregnation method at low temperature and tested as a catalyst in the ozonation of phenol and oxalic acid. Cu/AC was characterized using XRD, BET and SEM techniques. Compared with ozonation alone, the presence of Cu/AC in the ozonation processes significantly improves the degradation of phenol or oxalic acid. With the introduction of the hydroxyl radical scavenger, i.e., turt-butanol alcohol （t-BuOH）, the degradation efficiency of both phenol and oxalic acid in the Cu/AC catalyzed ozonation process decreases by 22% at 30 min. This indicates that Cu/AC accelerates ozone decomposition into certain concentration of hydroxyl radicals. The amount of Cu（II ） produced during the reaction of Cu/AC-catalyzed ozonation of phenol or oxalic acid is very small, which shows that the two processes are both heterogeneous catalytic ozonation reactions.
基金Project(50908110) supported by the National Natural Science Foundation of ChinaProject(2008AA062602) supported by the National High-Tech Research and Development Program of China+1 种基金Project(20090451431) supported by China Postdoctoral Science FoundationProject(2007PY01-10) supported by Young and Middle-aged Academic and Technical Back-up Personnel Program of Yunnan Province,China
文摘A novel type of metal oxide/activated carbon catalyst was prepared by sol-gel method for the hydrolysis of carbonyl sulfide （COS）. The influences of the calcination temperature, additive content （2.5%-10.0% Fe2O3, mass fraction） and the basic density of the activation process were thoroughly investigated. The surface of catalysts was characterized by Boehm titration. The products were characterized by scanning electron microscopy （SEM）, X-ray diffractometry （XRD） and X-ray photoelectron spectroscopy （XPS）. The results show that catalysts with 2.5%-5.0% Fe2O3 after calcining at 500 ℃ have superior activity. The conversion rate of COS increases with increasing the relative density of basic capacity loaded onto activated carbon（AC）, and the activity follows the order： KOH〉Na2CO3 〉NaHCO3. Boehm titration data clearly show that the total acidity increases （from 0.06 to 0.48 mmol/g） and the basic groups decrease （from 0.78 to 0.56 mmol/g） after COS hydrolysis and H2S adsorption. The XPS results show that the product of HzS may be absorbed by the interaction with metal compounds and 02 to form sulfate （171.28 eV） and element sulfur （164.44 eV）, which lead to catalysts poisoning.
