Cl is one of the main pollutants emitted from domestic waste incineration systems. In this study, we focused on the process of Ca dechlorination in the furnace of a circulating fluidized-bed waste incineration system....Cl is one of the main pollutants emitted from domestic waste incineration systems. In this study, we focused on the process of Ca dechlorination in the furnace of a circulating fluidized-bed waste incineration system. We analyzed the stability of CaCl_(2) and Ca in the furnace, the dechlorination process, and distribution of Cl in the incineration system. The results show that the optimal Ca/Cl molar ratio for Ca dechlorination in the circulating fluidized-bed waste incinerator is 2:1;moreover, the dechlorination product CaCl_(2) was found to decompose at high temperatures (> 850℃). At temperatures > 700℃, we measured CaCl_(2) decomposition rates up to 80%. Ca was added in the furnace, mainly to provide a dechlorination Ca source for the decomposition of limestone into tail flue gas. The amount of Ca^(2+) in the flue decreased gradually, parallelly to the temperature of the flue gas. Stable CaCl_(2) was formed after HCl was captured, and relatively small solid particles appeared in the ash collecting bag.展开更多
Enzymatic electrolysis cell(EEC)has advantages over microbial electrolysis cell(MEC)due to the needless of microbe inoculation and high-efficiency of enzymatic reaction.In this study,an EEC was first applied to achiev...Enzymatic electrolysis cell(EEC)has advantages over microbial electrolysis cell(MEC)due to the needless of microbe inoculation and high-efficiency of enzymatic reaction.In this study,an EEC was first applied to achieve the effective degradation of halogenated organic pollutants and dichloromethane(CH2Cl2)was utilized as a model pollutant.The results indicate that the degradation efficiency of CH2Cl2 after 2 hr reaction in the EEC was almost100%,which was significantly higher than that with enzyme(51.1%)or current(19.0%).The current induced the continuous regeneration of reduced glutathione(GSH),thus CH2Cl2 was degraded under the catalysis of GSH-dependent dehalogenase through stepwise dechlorination,and successively formed monochloromethane(CH3Cl)and methane(CH4).The kinetic result shows that with a current of 15 mA,the maximum specific degradation rate of CH2Cl2(3.77×10-3 hr-1)was increased by 5.7 times.The optimum condition for CH2Cl2 dechlorination was also obtained with pH,current and temperature of 7.0,15 mA and 35°C,respectively.Importantly,this study helps to understand the behavior of enzymes and the fate of halogenated organic pollutants with EEC,providing a possible treatment technology for halogenated organic pollutants.展开更多
Pollution from persistent organic chlorinated pollutants(POCPs)in water environments is attributable to historical reasons and the lack of effective discharge regulations.Electrochemical degradation of POCPs,as a key ...Pollution from persistent organic chlorinated pollutants(POCPs)in water environments is attributable to historical reasons and the lack of effective discharge regulations.Electrochemical degradation of POCPs,as a key study for POCP degradation,involves the use of electrons as reducing or oxidizing agents.The occurrence of this degradation depends on the environmental characteristics of the POCPs,the electrochemical materials used,and the technology and mechanisms involved.Furthermore,regarding the development of new materials and technologies,such as micro-,nano-,and atomic-sized materials,the degradation of POCPs achieves higher degradation efficiency and maximizes current utilization efficiency.In this review article,we first summarize the current status and future opportunities of the electrochemical degradation of POCPs.Environmental characteristics of POCPs facilitate a comparison of POCP degradation,and a comparison of electrochemical materials and their methods is made.Subsequently,we discuss technologies for the electrochemical degradation of POCPs from three aspects:oxidation,reduction,and a combination of oxidation and reduction.Moreover,the mechanisms were generalized in terms of molecular structure,electrode materials,and solution environment.In addition to maximizing the intrinsic enhancement factors of degradation,strategies to improve environmental accessibilities are equally important.This review article aims to effectively guide the advancement of POCP degradation and the remediation of environmental water pollution.展开更多
An unprecedented electrochemical oxidative trifunctionalization of olefins with diaryl disulfides/aryl thiols and N-chlorosuccinimide in an aqueous system is developed.Two C-Cl bonds,one C-S bond,and one S=O bond are ...An unprecedented electrochemical oxidative trifunctionalization of olefins with diaryl disulfides/aryl thiols and N-chlorosuccinimide in an aqueous system is developed.Two C-Cl bonds,one C-S bond,and one S=O bond are produced simultaneously in one step from simple and commercially available starting materials with clean energy.This tandem methodology features as mild reaction conditions,transition metal and additional oxidant free,broad substrate scope,good functional group compatibility,and gram scale preparation.展开更多
Silicon-phthalocyanine (SiPc) is chemically bonded to 3-aminopropltriethoxysilane (NH2(CH2)3Si(OC2H5)3, KH550) by the nucleophilic substituted reaction between the active chlorine of silicon dichlorine phthalocyanine ...Silicon-phthalocyanine (SiPc) is chemically bonded to 3-aminopropltriethoxysilane (NH2(CH2)3Si(OC2H5)3, KH550) by the nucleophilic substituted reaction between the active chlorine of silicon dichlorine phthalocyanine (SiPcCI2) and amino-group of KH550. The reacted product is hybridized with 3-glycidoxypropltrimethoxysilane (CH2OCHCH2O(CH2)3Si(OCH3)3, KH560) with sol-gel processing to form sol-gel inorganic material with good physical-chemical and optical properties. Due to tethering SiPc to the network, the aggregation of SiPc is effectively prevented in sol-gel derived matrix, and the doping concentration of SiPc in the form of monomer in the matrix is greatly enhanced. The cross-linkage of SiPcCI2 and KH550 is estimated and confirmed with FT-IR spectra. The optical limiting effects (OLE) of the gel with different content of SiPc are investigated with a frequency double Q-switched Nd3+:YAG laser of 8 nsec. pulse.展开更多
文摘Cl is one of the main pollutants emitted from domestic waste incineration systems. In this study, we focused on the process of Ca dechlorination in the furnace of a circulating fluidized-bed waste incineration system. We analyzed the stability of CaCl_(2) and Ca in the furnace, the dechlorination process, and distribution of Cl in the incineration system. The results show that the optimal Ca/Cl molar ratio for Ca dechlorination in the circulating fluidized-bed waste incinerator is 2:1;moreover, the dechlorination product CaCl_(2) was found to decompose at high temperatures (> 850℃). At temperatures > 700℃, we measured CaCl_(2) decomposition rates up to 80%. Ca was added in the furnace, mainly to provide a dechlorination Ca source for the decomposition of limestone into tail flue gas. The amount of Ca^(2+) in the flue decreased gradually, parallelly to the temperature of the flue gas. Stable CaCl_(2) was formed after HCl was captured, and relatively small solid particles appeared in the ash collecting bag.
基金supported by the National Natural Science Foundation of China (Nos. 21576241 and 51678528)Hangzhou Agricultural and Social Development Research Program (No. 20180533B03)
文摘Enzymatic electrolysis cell(EEC)has advantages over microbial electrolysis cell(MEC)due to the needless of microbe inoculation and high-efficiency of enzymatic reaction.In this study,an EEC was first applied to achieve the effective degradation of halogenated organic pollutants and dichloromethane(CH2Cl2)was utilized as a model pollutant.The results indicate that the degradation efficiency of CH2Cl2 after 2 hr reaction in the EEC was almost100%,which was significantly higher than that with enzyme(51.1%)or current(19.0%).The current induced the continuous regeneration of reduced glutathione(GSH),thus CH2Cl2 was degraded under the catalysis of GSH-dependent dehalogenase through stepwise dechlorination,and successively formed monochloromethane(CH3Cl)and methane(CH4).The kinetic result shows that with a current of 15 mA,the maximum specific degradation rate of CH2Cl2(3.77×10-3 hr-1)was increased by 5.7 times.The optimum condition for CH2Cl2 dechlorination was also obtained with pH,current and temperature of 7.0,15 mA and 35°C,respectively.Importantly,this study helps to understand the behavior of enzymes and the fate of halogenated organic pollutants with EEC,providing a possible treatment technology for halogenated organic pollutants.
基金supported by the National Natural Science Foundation of China(Nos.52100116 and 21207077)the Urban Agriculture and Forestry Emerging Interdisciplinary Platform Project,the Science and Technology Innovation Support Program of Beijing University of Agriculture,the Fund of the Key Laboratory of Urban Agriculture in North China(No.KFKT-2024008).
文摘Pollution from persistent organic chlorinated pollutants(POCPs)in water environments is attributable to historical reasons and the lack of effective discharge regulations.Electrochemical degradation of POCPs,as a key study for POCP degradation,involves the use of electrons as reducing or oxidizing agents.The occurrence of this degradation depends on the environmental characteristics of the POCPs,the electrochemical materials used,and the technology and mechanisms involved.Furthermore,regarding the development of new materials and technologies,such as micro-,nano-,and atomic-sized materials,the degradation of POCPs achieves higher degradation efficiency and maximizes current utilization efficiency.In this review article,we first summarize the current status and future opportunities of the electrochemical degradation of POCPs.Environmental characteristics of POCPs facilitate a comparison of POCP degradation,and a comparison of electrochemical materials and their methods is made.Subsequently,we discuss technologies for the electrochemical degradation of POCPs from three aspects:oxidation,reduction,and a combination of oxidation and reduction.Moreover,the mechanisms were generalized in terms of molecular structure,electrode materials,and solution environment.In addition to maximizing the intrinsic enhancement factors of degradation,strategies to improve environmental accessibilities are equally important.This review article aims to effectively guide the advancement of POCP degradation and the remediation of environmental water pollution.
基金the National Natural Science Foundation of China(Nos.21702175,21961037,22061040 and 22161044)the Program for Tianshan Innovative Research Team of Xinjiang Uygur Autonomous Region(No.2021D14011)the Natural Science Foundation of Xinjiang Uygur Autonomous Region(No.2020D01C077)for support of this research.
文摘An unprecedented electrochemical oxidative trifunctionalization of olefins with diaryl disulfides/aryl thiols and N-chlorosuccinimide in an aqueous system is developed.Two C-Cl bonds,one C-S bond,and one S=O bond are produced simultaneously in one step from simple and commercially available starting materials with clean energy.This tandem methodology features as mild reaction conditions,transition metal and additional oxidant free,broad substrate scope,good functional group compatibility,and gram scale preparation.
文摘Silicon-phthalocyanine (SiPc) is chemically bonded to 3-aminopropltriethoxysilane (NH2(CH2)3Si(OC2H5)3, KH550) by the nucleophilic substituted reaction between the active chlorine of silicon dichlorine phthalocyanine (SiPcCI2) and amino-group of KH550. The reacted product is hybridized with 3-glycidoxypropltrimethoxysilane (CH2OCHCH2O(CH2)3Si(OCH3)3, KH560) with sol-gel processing to form sol-gel inorganic material with good physical-chemical and optical properties. Due to tethering SiPc to the network, the aggregation of SiPc is effectively prevented in sol-gel derived matrix, and the doping concentration of SiPc in the form of monomer in the matrix is greatly enhanced. The cross-linkage of SiPcCI2 and KH550 is estimated and confirmed with FT-IR spectra. The optical limiting effects (OLE) of the gel with different content of SiPc are investigated with a frequency double Q-switched Nd3+:YAG laser of 8 nsec. pulse.
