To investigate the enhancing effect of Mn on the performance of simultaneous catalytic oxidation of AsH_(3)and PH_(3)by CuO-Al_(2)O_(3)in a reducing atmosphere under micro-oxygen conditions,Cu-Mn modifiedγ-Al_(2)O_(3...To investigate the enhancing effect of Mn on the performance of simultaneous catalytic oxidation of AsH_(3)and PH_(3)by CuO-Al_(2)O_(3)in a reducing atmosphere under micro-oxygen conditions,Cu-Mn modifiedγ-Al_(2)O_(3)catalysts were prepared.The characteristics of the catalysts showed that Mn reduced the crystallinity of the active CuO component,increased the number of oxygen vacancies and acidic sites on the catalyst surface,enhanced the mobility of surface oxygen,and the interaction between copper and manganese promoted the redox cycling ability of the catalysts and improved their oxidation performance,which increased the conversion frequency(TOF)by 2.54×10^(-2)to 3.07×10^(-2)sec^(-1).On the other hand,the introduction of Mn reduced the production of phosphate and As_(2)O_(3)on the catalyst surface by30.96%and 44.9%,which reduced the coverage and inerting of the active sites by phosphate and As_(2)O_(3),resulting in an 8 hr(6 hr)improvement in the stability of PH_(3)(AsH_(3))removal.展开更多
La_(2)O_(3)/Bi_(2)O_(3)photocatalysts were prepared by impregnation of Bi_(2)O_(3)with an aqueous solution of lanthanum precursor followed by calcination at different temperatures.The composite materials were used for...La_(2)O_(3)/Bi_(2)O_(3)photocatalysts were prepared by impregnation of Bi_(2)O_(3)with an aqueous solution of lanthanum precursor followed by calcination at different temperatures.The composite materials were used for the first time for the photocatalytic removal of Hg~0 from a simulated flue gas under UV light irradiation.The results showed that the sample containing 6 wt.%La_(2)O_(3)and calcined at 500°C has the highest dispersion of the active sites,which was promoted by the strong interaction with the support(i.e.,the formation of Bi-O-La species).Since they are fully accessible on the surface,the material also exhibits excellent optical properties while the heterojunction formed in La_(2)O_(3)/Bi_(2)O_(3)promotes the separation and migration of photoelectron-hole pairs and thus Hg~0 oxidation efficiency is enhanced.The effects of the various factors(e.g.,the reaction temperature and composition of the simulated flue gas(i.e.,O_(2),NO,H_(2)O,and SO_(2)))on the efficiency of the Hg~0 photocatalytic oxidation were investigated.The results demonstrated that O_(2)and SO_(2)enhanced the efficiency of the reaction while the reaction temperature,NO,and H_(2)O had an inhibitory effect.展开更多
基金supported by the National Natural Science Foundation of China (Nos.51868030,52070090,52100122,22266019,and 21876071)the Science and Technology Planning Project of Yunnan Province (Nos.202001AU070031,202101BE070001-030,and 202101BC070001-009)Applied Basic Research Program of Yunnan Province (No.2019FD043)。
文摘To investigate the enhancing effect of Mn on the performance of simultaneous catalytic oxidation of AsH_(3)and PH_(3)by CuO-Al_(2)O_(3)in a reducing atmosphere under micro-oxygen conditions,Cu-Mn modifiedγ-Al_(2)O_(3)catalysts were prepared.The characteristics of the catalysts showed that Mn reduced the crystallinity of the active CuO component,increased the number of oxygen vacancies and acidic sites on the catalyst surface,enhanced the mobility of surface oxygen,and the interaction between copper and manganese promoted the redox cycling ability of the catalysts and improved their oxidation performance,which increased the conversion frequency(TOF)by 2.54×10^(-2)to 3.07×10^(-2)sec^(-1).On the other hand,the introduction of Mn reduced the production of phosphate and As_(2)O_(3)on the catalyst surface by30.96%and 44.9%,which reduced the coverage and inerting of the active sites by phosphate and As_(2)O_(3),resulting in an 8 hr(6 hr)improvement in the stability of PH_(3)(AsH_(3))removal.
基金This work was supported by the National Natural Science Foundation of China （Grant Nos. Ul137603, 51268021 and 51368026）, the National High Technology Research and Development Program of China （No. 2012AA062504） and the Applied Basic Research Program of Yunnan （Nos. 2011FB027 and 2011FA010）.
基金supported by the National Key Research and Development Program of China(Nos.2017YFC0210500 and 2018YFC0213400)the National Natural Science Foundation of China(Nos.52070090 and 51868030)。
文摘La_(2)O_(3)/Bi_(2)O_(3)photocatalysts were prepared by impregnation of Bi_(2)O_(3)with an aqueous solution of lanthanum precursor followed by calcination at different temperatures.The composite materials were used for the first time for the photocatalytic removal of Hg~0 from a simulated flue gas under UV light irradiation.The results showed that the sample containing 6 wt.%La_(2)O_(3)and calcined at 500°C has the highest dispersion of the active sites,which was promoted by the strong interaction with the support(i.e.,the formation of Bi-O-La species).Since they are fully accessible on the surface,the material also exhibits excellent optical properties while the heterojunction formed in La_(2)O_(3)/Bi_(2)O_(3)promotes the separation and migration of photoelectron-hole pairs and thus Hg~0 oxidation efficiency is enhanced.The effects of the various factors(e.g.,the reaction temperature and composition of the simulated flue gas(i.e.,O_(2),NO,H_(2)O,and SO_(2)))on the efficiency of the Hg~0 photocatalytic oxidation were investigated.The results demonstrated that O_(2)and SO_(2)enhanced the efficiency of the reaction while the reaction temperature,NO,and H_(2)O had an inhibitory effect.
