Activated carbon derived from solid hazardous waste scrap tires was evaluated as a potential adsorbent for cationic dye removal. The adsorption process with respect to operating parameters was investigated to evaluate...Activated carbon derived from solid hazardous waste scrap tires was evaluated as a potential adsorbent for cationic dye removal. The adsorption process with respect to operating parameters was investigated to evaluate the adsorption characteristics of the activated pyrolytic tire char （APTC） for Rhodamine B （RhB）. Systematic research including equilibrium, kinetics and thermodynamic studies was performed. The results showed that APTC was a potential adsorbent for RhB with a higher adsorption capacity than most adsorbents. Solution pH and temperature exert significant influence while ionic strength showed little effect on the adsorption process. The adsorption equilibrium data obey Langmuir isotherm and the kinetic data were well described by the pseudo second-order kinetic model. The adsorption process followed intra-particle diffusion model with more than one process affecting the adsorption process. Thermodynamic study confirmed that the adsorption was a physisorption process with spontaneous, endothermic and random characteristics.展开更多
A total of 168 PM_(10)samples were collected during the year of 2005 at eight sites in the city of Wuxi in China.Fifteen chemical elements,three water-soluble ions,total carbon and organic carbon were analyzed.Six sou...A total of 168 PM_(10)samples were collected during the year of 2005 at eight sites in the city of Wuxi in China.Fifteen chemical elements,three water-soluble ions,total carbon and organic carbon were analyzed.Six source categories were identified and their contributions to ambient PM_(10)in Wuxi were estimated using a nested chemical mass balance method that reduces the effects of colinearity on the chemical mass balance model.In addition,the concentrations of secondary aerosols,such as secondary organic carbon,sulfate and nitrate,were quantified.The spatially averaged PM_(10)was high in the spring and winter(123μg·m^(-3)and low in the summer-fall(90μg·m^(-3)).According to the result of source apportionment,resuspended dust was the largest contributor to ambient PM_(10),accounting for more than 50%of the PM_(10)mass.Coal combustion(14.6%)and vehicle exhaust(9.4%)were also significant source categories of ambient PM_(10).Construction and cement dust,sulfates,secondary organic carbon,and nitrates made contributions ranging between 4.1%and 4.9%.Other source categories such as steel manufacturing dust and soil dust made low contributions to ambient PM_(10).展开更多
TiO_(2) supported on active carbon fiber(TiO_(2)/ACF),an absorbable photocatalyst,is a new kind of material applied in air purification.In this paper,the influence of environmental temperature(T)and relative humidity(...TiO_(2) supported on active carbon fiber(TiO_(2)/ACF),an absorbable photocatalyst,is a new kind of material applied in air purification.In this paper,the influence of environmental temperature(T)and relative humidity(RH)on the gas-solid adsorption of toluene and the photocatalytic oxidation(PCO)efficiency of adsorbed toluene on TiO_(2)/ACF were studied,and then,the purification capability of TiO_(2)/ACF was estimated.PCO results showed that although the PCO efficiency increased under high RH and T levels,the amount of adsorption of toluene decreased.Moreover,quantitative analysis results of intermediates indicated that more environmental risk emerged when PCO of toluene was carried out at higher environmental T and RH levels because more toxic intermediates would be accumulated on the TiO_(2)/ACF.So,it is significant to control the environmental T and RH conditions in the application of the PCO technique.T 525uC and RH530% is the optimal condition for purifying toluene in our experimental system.展开更多
基金supported by the National Key Technologies R & D Program of China (No. 2006BAC02A12)the Key Technologies R & D Program of Tianjin, China (No.07ZCGYSH02000)the Natural Science Foundationof Tianjin, China (No. 08JCZDJC21400).
文摘Activated carbon derived from solid hazardous waste scrap tires was evaluated as a potential adsorbent for cationic dye removal. The adsorption process with respect to operating parameters was investigated to evaluate the adsorption characteristics of the activated pyrolytic tire char （APTC） for Rhodamine B （RhB）. Systematic research including equilibrium, kinetics and thermodynamic studies was performed. The results showed that APTC was a potential adsorbent for RhB with a higher adsorption capacity than most adsorbents. Solution pH and temperature exert significant influence while ionic strength showed little effect on the adsorption process. The adsorption equilibrium data obey Langmuir isotherm and the kinetic data were well described by the pseudo second-order kinetic model. The adsorption process followed intra-particle diffusion model with more than one process affecting the adsorption process. Thermodynamic study confirmed that the adsorption was a physisorption process with spontaneous, endothermic and random characteristics.
基金This work was supported by the National Natural Science Foundation of China(Grant No.20877042)National Science and Technology Supporting Program during the Eleventh Five-year Plan Period(No.2007BAC16B01).
文摘A total of 168 PM_(10)samples were collected during the year of 2005 at eight sites in the city of Wuxi in China.Fifteen chemical elements,three water-soluble ions,total carbon and organic carbon were analyzed.Six source categories were identified and their contributions to ambient PM_(10)in Wuxi were estimated using a nested chemical mass balance method that reduces the effects of colinearity on the chemical mass balance model.In addition,the concentrations of secondary aerosols,such as secondary organic carbon,sulfate and nitrate,were quantified.The spatially averaged PM_(10)was high in the spring and winter(123μg·m^(-3)and low in the summer-fall(90μg·m^(-3)).According to the result of source apportionment,resuspended dust was the largest contributor to ambient PM_(10),accounting for more than 50%of the PM_(10)mass.Coal combustion(14.6%)and vehicle exhaust(9.4%)were also significant source categories of ambient PM_(10).Construction and cement dust,sulfates,secondary organic carbon,and nitrates made contributions ranging between 4.1%and 4.9%.Other source categories such as steel manufacturing dust and soil dust made low contributions to ambient PM_(10).
基金We are pleased to acknowledge research support from“Joint Research Grant to both Nankai University and Tianjin University”and“Trans-Century Training Program Foundation for the Talents”sponsored by the Ministry of Education,China,and the project under Tianjin’s Science and Technology Development Plan(Grant No.06YFGPSHO4200).
文摘TiO_(2) supported on active carbon fiber(TiO_(2)/ACF),an absorbable photocatalyst,is a new kind of material applied in air purification.In this paper,the influence of environmental temperature(T)and relative humidity(RH)on the gas-solid adsorption of toluene and the photocatalytic oxidation(PCO)efficiency of adsorbed toluene on TiO_(2)/ACF were studied,and then,the purification capability of TiO_(2)/ACF was estimated.PCO results showed that although the PCO efficiency increased under high RH and T levels,the amount of adsorption of toluene decreased.Moreover,quantitative analysis results of intermediates indicated that more environmental risk emerged when PCO of toluene was carried out at higher environmental T and RH levels because more toxic intermediates would be accumulated on the TiO_(2)/ACF.So,it is significant to control the environmental T and RH conditions in the application of the PCO technique.T 525uC and RH530% is the optimal condition for purifying toluene in our experimental system.
