o-Dichlorobenzene (o-DCB) was dechlorinated by Pd/Fe powder in water through catalytic reduction. The dechlorination reaction is believed to take place on the surface site of the catalyst via a pseudo-first-order reac...o-Dichlorobenzene (o-DCB) was dechlorinated by Pd/Fe powder in water through catalytic reduction. The dechlorination reaction is believed to take place on the surface site of the catalyst via a pseudo-first-order reaction. The final reduction product of o-DCB is benzene. The dechlorination rate increases with the increase of bulk loading of palladium due to the increase of both the surface loading of palladium and the total surface area. Dechlorination efficiency accounts for 90% at Pd/Fe mass ratio 0.02% and metal to solution ratio about 53.3 g·L^-1 in 120 minutes. Dechlorination is affected by the reaction temperature, pH, Pd/Fe ratio and the addition of Pd/Fe. Ea is found to be 102.5kJ·mol^-1 in the temperature range of 287--313K.展开更多
In order to study the degradation process of dioxins in industrial flue gas,the decomposition of o-dichlorobenzene(o-DCB)in a DBD plasma catalytic reactor was investigated.The results showed that an NTP-catalyzed syst...In order to study the degradation process of dioxins in industrial flue gas,the decomposition of o-dichlorobenzene(o-DCB)in a DBD plasma catalytic reactor was investigated.The results showed that an NTP-catalyzed system,especially using the Cu Mn Ti Oxcatalyst,had better o-DCB degradation performance compared to plasma alone.The combination of the Cu Mn Ti Oxcatalyst with NTP can achieve a degradation efficiency of up to 97.2%for o-DCB;the selectivity of CO and CO_(2)and the carbon balance were 40%,45%,and 85%,respectively.The dielectric constant and electrical property results indicated that the surface discharge capacity of the catalysts played a major role in the degradation of o-DCB,and a higher dielectric constant could suppress the plasma expansion and enhance the duration of the plasma discharge per discharge cycle.According to the O1s XPS and O_(2)-TPD results,the conversion of CO to CO_(2)follows the M-v-K mechanism;thus,the active species on the catalyst surface play an important role.Moreover,the Cu Mn Ti Oxand NTP mixed system exhibited excellent stability,which is probably because Cu doping improved the lifetime of the catalyst.This work can provide an experimental and theoretical basis for research in the degradation of o-DCB by plasma catalyst systems.展开更多
Hierachically porous (HP) CuO/α-Fe2O3/SiO2 composite material was fabricated by sol-gel method and multi-hydrothermal processes using HP-SiO2 as support.The resulting material was characterized by N2 adsorption-des...Hierachically porous (HP) CuO/α-Fe2O3/SiO2 composite material was fabricated by sol-gel method and multi-hydrothermal processes using HP-SiO2 as support.The resulting material was characterized by N2 adsorption-desorption,X-ray diffraction and scanning electron microscopy.The as-prepared CuO/Fe2O3/HP-SiO2 sample,with α-Fe2O3 and CuO nanocrystals,possessed a co-continuous skeleton,through-macroporous and mesoporous structure.Its catalytic behavior for CO and o-DCB oxidation was investigated.The result showed that CuO/Fe2O3/HP-SiO2 catalyst exhibited high catalytic activity for both CO and o-DCB oxidation,indicating its potential application in combined abatement of CO and chlorinated volatile organic compounds.展开更多
Ionic strength conditions in distribution experiments with single ions are very important for evaluating their distribution properties. Distribution experiments of picrates (MPic) with M = Ag(I) and Li(I)-Cs(I) into o...Ionic strength conditions in distribution experiments with single ions are very important for evaluating their distribution properties. Distribution experiments of picrates (MPic) with M = Ag(I) and Li(I)-Cs(I) into o-dichlorobenzene (oDCBz) were performed at 298 K by changing volume ratios (Vorg/V) between water and oDCBz phases, where “org” shows an organic phase. Simultaneously, an analytic equation with the Vorg/V variation was derived in order to analyze such distribution systems. Additionally, the AgPic distribution into nitrobenzene (NB), dichloromethane, and 1,2-dichloroethene (DCE) and the NaB(C6H5) 4 (=NaBPh4) one into NB and DCE were studied at 298 K under the conditions of various Vorg/V values. So, extraction constants (Kex) for MPic into the org phases, their ion-pair formation constants (KMA,org) for MA = MPic in the org ones, and standard distribution constants () for the M(I) transfers between the water and org bulk phases with M = Ag and Li-Cs were determined at the distribution equilibrium potential (dep) of zero V between the bulk phases and also the Kex (NaA), KNaA,org, and values were done at A-=BPh-4. Here, the symbols Kex, KMA,org, and or were defined as [MA] org/[M+][A-], [MA] org/[M+]org [A-]org, and [M+]org/[M+] or [A-]org/[A-] at dep = 0, respectively. Especially, the ionic strength dependences of Kex and KMPic,org were examined at M = Li(I)-K(I) and org = oDCBz. From above, the conditional distribution constants, KD,BPh4 and KD,Cs, were classified by checking the experimental conditions of the I, Iorg, and dep values.展开更多
基金the Returnee Foundation of Ministry of Education of China (No. 2002-247)Science and Technology Project of Zhejiang Province (No. 2004C34006).
文摘o-Dichlorobenzene (o-DCB) was dechlorinated by Pd/Fe powder in water through catalytic reduction. The dechlorination reaction is believed to take place on the surface site of the catalyst via a pseudo-first-order reaction. The final reduction product of o-DCB is benzene. The dechlorination rate increases with the increase of bulk loading of palladium due to the increase of both the surface loading of palladium and the total surface area. Dechlorination efficiency accounts for 90% at Pd/Fe mass ratio 0.02% and metal to solution ratio about 53.3 g·L^-1 in 120 minutes. Dechlorination is affected by the reaction temperature, pH, Pd/Fe ratio and the addition of Pd/Fe. Ea is found to be 102.5kJ·mol^-1 in the temperature range of 287--313K.
基金supported by the National Key R&D Program of China(No.2022YFE0208100)the Key Science and Technology Planning Project of HBIS Group Co.,Ltd.(No.HG2020204-2)+1 种基金the Hebei Provincial Key R&D Program Project(No.22373805D)the Guangdong Air Pollution Control Engineering Laboratory Open Fund Project(No.20193236-09-06)。
文摘In order to study the degradation process of dioxins in industrial flue gas,the decomposition of o-dichlorobenzene(o-DCB)in a DBD plasma catalytic reactor was investigated.The results showed that an NTP-catalyzed system,especially using the Cu Mn Ti Oxcatalyst,had better o-DCB degradation performance compared to plasma alone.The combination of the Cu Mn Ti Oxcatalyst with NTP can achieve a degradation efficiency of up to 97.2%for o-DCB;the selectivity of CO and CO_(2)and the carbon balance were 40%,45%,and 85%,respectively.The dielectric constant and electrical property results indicated that the surface discharge capacity of the catalysts played a major role in the degradation of o-DCB,and a higher dielectric constant could suppress the plasma expansion and enhance the duration of the plasma discharge per discharge cycle.According to the O1s XPS and O_(2)-TPD results,the conversion of CO to CO_(2)follows the M-v-K mechanism;thus,the active species on the catalyst surface play an important role.Moreover,the Cu Mn Ti Oxand NTP mixed system exhibited excellent stability,which is probably because Cu doping improved the lifetime of the catalyst.This work can provide an experimental and theoretical basis for research in the degradation of o-DCB by plasma catalyst systems.
基金supported by the National Natural Science Foundation of China (No. 20977052 and 21177066)the Science and Technology Commission Foundation of Tianjin (No. 11JCYBJC05100)+1 种基金the Chinese Academy of Sciences(No. KZCX2-YW-420)the National 973 program (No. 2009CB421606)
文摘Hierachically porous (HP) CuO/α-Fe2O3/SiO2 composite material was fabricated by sol-gel method and multi-hydrothermal processes using HP-SiO2 as support.The resulting material was characterized by N2 adsorption-desorption,X-ray diffraction and scanning electron microscopy.The as-prepared CuO/Fe2O3/HP-SiO2 sample,with α-Fe2O3 and CuO nanocrystals,possessed a co-continuous skeleton,through-macroporous and mesoporous structure.Its catalytic behavior for CO and o-DCB oxidation was investigated.The result showed that CuO/Fe2O3/HP-SiO2 catalyst exhibited high catalytic activity for both CO and o-DCB oxidation,indicating its potential application in combined abatement of CO and chlorinated volatile organic compounds.
文摘Ionic strength conditions in distribution experiments with single ions are very important for evaluating their distribution properties. Distribution experiments of picrates (MPic) with M = Ag(I) and Li(I)-Cs(I) into o-dichlorobenzene (oDCBz) were performed at 298 K by changing volume ratios (Vorg/V) between water and oDCBz phases, where “org” shows an organic phase. Simultaneously, an analytic equation with the Vorg/V variation was derived in order to analyze such distribution systems. Additionally, the AgPic distribution into nitrobenzene (NB), dichloromethane, and 1,2-dichloroethene (DCE) and the NaB(C6H5) 4 (=NaBPh4) one into NB and DCE were studied at 298 K under the conditions of various Vorg/V values. So, extraction constants (Kex) for MPic into the org phases, their ion-pair formation constants (KMA,org) for MA = MPic in the org ones, and standard distribution constants () for the M(I) transfers between the water and org bulk phases with M = Ag and Li-Cs were determined at the distribution equilibrium potential (dep) of zero V between the bulk phases and also the Kex (NaA), KNaA,org, and values were done at A-=BPh-4. Here, the symbols Kex, KMA,org, and or were defined as [MA] org/[M+][A-], [MA] org/[M+]org [A-]org, and [M+]org/[M+] or [A-]org/[A-] at dep = 0, respectively. Especially, the ionic strength dependences of Kex and KMPic,org were examined at M = Li(I)-K(I) and org = oDCBz. From above, the conditional distribution constants, KD,BPh4 and KD,Cs, were classified by checking the experimental conditions of the I, Iorg, and dep values.