The feasibility of a new method for separating arsenic from arsenic-antimony-bearing dusts using Cu S was put forward,in which Sb was transformed into Sb2O4 and Sb2S3 that stayed in the roasted calcine while As was vo...The feasibility of a new method for separating arsenic from arsenic-antimony-bearing dusts using Cu S was put forward,in which Sb was transformed into Sb2O4 and Sb2S3 that stayed in the roasted calcine while As was volatilized in the form of As4O6.The factors such as roasting temperature and Cu S addition amount were studied using XRD,EPMA and SEM-EDS.Cu S has an active effect on the separation of arsenic due to the destruction of(Sb,As)2 O3 structures in the original dust and the simultaneous release of As in the form of As4O6.At a roasting temperature of 400°C and Cu S addition amount of 130%,the volatilization rates of arsenic and antimony reach 97.80 wt.%and 8.29 wt.%,respectively.Further,the high As volatile matter can be used to prepare ferric arsenate after it is oxidized,with this treatment rendering the vapor harmlessness.展开更多
The ribbons of Cu-Cr alloys with high Cr content (15%- 35%, mass fraction) were prepared by rapid solidification. The microstructures of solidified samples were analyzed by scanning electron microscopy and transmissio...The ribbons of Cu-Cr alloys with high Cr content (15%- 35%, mass fraction) were prepared by rapid solidification. The microstructures of solidified samples were analyzed by scanning electron microscopy and transmission electron microscopy. The results reveal that a representative liquid phase separation microstructures are observed in Cu75Cr25 ribbons solidified at a cooling rate of about 104K/s. The liquid phase separation is not restrained when the cooling rate is enhanced to about 107K/s. However, the size of Cr particles solidified from Cr-rich liquid or Cr-rich regions in alloy melts could be refined by increasing the cooling rates. The size of Cr particles increases with increasing Cr contents when the ribbons contain 15% to 35%Cr.展开更多
An anion-exchange-based chromatographic separation approach was developed to selectively recover zinc and copper from the high-chlorine raffinate generated in the process of germanium chlorination distillation using 7...An anion-exchange-based chromatographic separation approach was developed to selectively recover zinc and copper from the high-chlorine raffinate generated in the process of germanium chlorination distillation using 717 resins based on the coordination difference between Zn^(2+)/Cu^(2+)and Cl^(-).The theoretical calculation and spectroscopic analyses suggested that the coordination between Zn^(2+)and Cl^(-)is much stronger than that between Cu^(2+)and Cl^(-),and the Cl-concentration significantly affects Zn(Ⅱ)and Cu(Ⅱ)species.The factors involving Cl-concentration,resin dosage,shaking speed,and temperature were investigated to determine the optimal condition,and the maximum separation factor of Zn/Cu reached as high as 479.2.The results of the adsorption isotherms,adsorption kinetics,SEM,FTIR,and XPS analyses indicated that the process followed the monolayer uniform chemisorption.Through the continuous adsorption experiments,Zn(Ⅱ)and Cu(Ⅱ)in the high-chlorine raffinate were separately recovered,allowing the reuse of residual waste acid and germanium.展开更多
The flotation separation of Cu–Fe sulfide minerals at low alkalinity can be achieved using selective depressants.In the flotation system of Cu–Fe sulfide minerals,depressants usually preferentially interact with the...The flotation separation of Cu–Fe sulfide minerals at low alkalinity can be achieved using selective depressants.In the flotation system of Cu–Fe sulfide minerals,depressants usually preferentially interact with the pyrite surface to render the mineral surface hydrophilic and hinder the adsorption of the collector.This review summarizes the advances in depressants for the flotation separation of Cu–Fe sulfide minerals at low alkalinity.These advances include use of inorganic depressants (oxidants and sulfur–oxygen compounds),natural polysaccharides (starch,dextrin,konjac glucomannan,and galactomannan),modified polymers (carboxymethyl cellulose,polyacrylamide,lignosulfonate,and tricarboxylate sodium starch),organic acids (polyglutamic acid,sodium humate,tannic acid,pyrogallic acid,salicylic acid,and lactic acid),sodium dimethyl dithiocarbamate,and diethylenetriamine.The potential application of specific inorganic and organic depressants in the flotation separation of Cu–Fe sulfide minerals at low alkalinity is reviewed.The advances in the use of organic depressants with respect to the flotation separation of Cu–Fe sulfide minerals are comprehensively detailed.Additionally,the depression performances and mechanisms of different types of organic depressants on mineral surfaces are summarized.Finally,several perspectives on depressants vis-à-vis flotation separation of Cu–Fe sulfide minerals at low alkalinity are proposed.展开更多
The effects of Ni addition on the liquid phase separation and giant magnetoresi stance (GMR) of Cu Co alloys were discussed. The results reveal that Ni additio n can partially restrain the liquid phase separation of C...The effects of Ni addition on the liquid phase separation and giant magnetoresi stance (GMR) of Cu Co alloys were discussed. The results reveal that Ni additio n can partially restrain the liquid phase separation of Cu Co alloys, resultin g in a decrease of volume fraction for the Co rich particles separated from the liquid phase and in refined microstructures. The composition analyses indicate t hat Ni is dissolved in both the Co rich and the Cu rich phases, but Ni content in the Co rich phase is much higher than that in the Cu matrix. At the same ti me, Ni addition enhance the solubility between Cu and Co, especially Cu in Co s olid solution. Ni alloying into Cu Co alloys can fully prevent the liquid phase separation during melt spinning, which is very beneficial to improve GMR of Cu Co alloys.展开更多
The homogeneous liquid was separated into two phases, （Fe, Co）-rich LI and Cu-rich L2, once the melt was undercooled below a liquid-phase separation temperature Tsep. If the duration from Tsep to Tsl （solidificatio...The homogeneous liquid was separated into two phases, （Fe, Co）-rich LI and Cu-rich L2, once the melt was undercooled below a liquid-phase separation temperature Tsep. If the duration from Tsep to Tsl （solidification temperature of LI phase）, termed the liquid-phase separation interval Δt, exceeded a critical value, an eggtype structure was observed. By utilizing differential thermal analyses （DTA）, the solidification process of the undercooled Fe-Co-Cu alloys was studied. Additionally, an immiscible boundary was obtained, which was a convex parabola with a symmetrical axis of XCu=0.52. Depending on the relative amounts of LI and L2, the minor phase was nucleated firstly to form liquid droplets and separated from the original liquids at the beginning of liquid-phase separation.展开更多
Cu（OH）2 nanowires were prepared and incorporated into poly（vinylidene fluoride）（PVDF） to fabricate Cu（OH）2-PVDF ultrafiltration（UF） membrane via immersion precipitation phase inversion process. The effect of...Cu（OH）2 nanowires were prepared and incorporated into poly（vinylidene fluoride）（PVDF） to fabricate Cu（OH）2-PVDF ultrafiltration（UF） membrane via immersion precipitation phase inversion process. The effect of Cu（OH）2 nanowires on the morphology of membranes was investigated by X-ray photoelectron spectroscopy（XPS）, Fourier transform infrared（FTIR） spectroscopy, atomic force microscopy（AFM）, scanning electron microscopy（SEM） and X-ray diffraction（XRD） measurements. The results showed that all the Cu（OH）2-PVDF membranes had wider fingerlike pore structure and better hydrophilicity, smoother surface than pristine PVDF membrane due to the incorporation of Cu（OH）2 nanowires. In addition, water flux and bovine serum albumin（BSA） rejection were also measured to investigate the filtration performance of membranes. The results indicated that all the Cu（OH）2-PVDF membranes had high water flux, outstanding BSA rejection and excellent antifouling properties. It is worth mentioning that the optimized performance could be obtained when the Cu（OH）2 nanowires content reached 1.2 wt%. Furthermore, the membrane with 1.2 wt% Cu（OH）2 nanowires showed outstanding oil-water emulsion separation capability.展开更多
Hydrogen,with the merits of zero emissions and high energy density,is one of the promising green energy sources.Seeking for high efficiency and low-cost catalysts is one of the key issues for hydrogen evolution and it...Hydrogen,with the merits of zero emissions and high energy density,is one of the promising green energy sources.Seeking for high efficiency and low-cost catalysts is one of the key issues for hydrogen evolution and its practical applications.Nano-structured metal cocatalysts are widely used to improve the photocatalytic performance via surface electronic structure/properties optimization of the catalyst.Herein,we report ultra-fine(*1 nm)Cu clusters decorated hydrangea-like TiO_(2)systems for photocatalytic hydrogen evolution.The pristine hydrangea-like TiO_(2)support shows a promising performance of hydrogen evolution(1.8 mmol·h^(-1)·g^(-1)),which is*10.7 times higher than that of the commercial P25(168 lmol·h^(-1)·g^(-1)).After ultra-fine Cu clusters decoration,a maximal hydrogen evolution performance(3.7 mmol·h^(-1)·g^(-1))is achieved in the optimized system 6Cu–TiO_(2)(6 wt%).Experimental and theoretical studies demonstrate that the ultra-fine Cu clusters decoration could promote the charge separation and transfer process effectively.The Cu clusters also act as reaction sites for reduction of H_(2)O to H2.These results are of great importance for the study of Cu-based co-catalyst systems and also shed light on the development of other non-noble metal co-catalysts in photocatalysis hydrogen evolution.展开更多
To select the proper composition and obtain an overall material?microstructure?property relationship for Cu?Fe alloy, theeffect of Fe content on microstructure and properties of Cu?Fe-based composite coatings by laser...To select the proper composition and obtain an overall material?microstructure?property relationship for Cu?Fe alloy, theeffect of Fe content on microstructure and properties of Cu?Fe-based composite coatings by laser induction hybrid rapid claddingwas investigated. Microstructure characterization of the composite coatings was tested utilizing SEM, XRD and EDS. Microhardnessmeasurement was executed to evaluate the mechanical properties of the composite coatings. The results show that for low Fe content,the composite coating presents a feature that Fe-rich equiaxed dendrites are embedded in the Cu-rich matrix. With increasing Fecontent, the Fe-rich particles are dispersed in the Cu-rich matrix. With further increasing Fe content, large amounts of Cu-richparticles are homogeneously dispersed in the interdendrite of the Fe-rich matrix. Correspondingly, the average microhardness of thecomposite coatings increases gradually with the increase of Fe content and the microhardness of Cu14.5Fe83Si2C0.5 coating is muchtwice higher than that of the substrate.展开更多
Although the internal electric field(IEF)of photocatalysts is acknowledged as a potent driving force for photocharge separation,modulating the IEF intensity to achieve enhanced photocatalytic performances remains a ch...Although the internal electric field(IEF)of photocatalysts is acknowledged as a potent driving force for photocharge separation,modulating the IEF intensity to achieve enhanced photocatalytic performances remains a challenge.Herein,cuprous sulfide nanosheets with different Cu vacancy concentration were employed to study IEF modulation and corresponding direct charge transfer.Among the samples,Cu_(1.8)S nanosheets possessed intensified IEF intensity compared with those of Cu_(2)S and Cu_(1.95)S nanosheets,suggesting that an enhanced IEF intensity could be achieved by introducing more Cu vacancies.This intensified IEF of Cu_(1.8)S nanosheets induced numerous photogenerated electrons to migrate to its surface,and the dissociative electrons were then captured by Cu vacancies,resulting in efficient charge separation spatially.In addition,the Cu vacancies on Cu_(1.8)S nanosheets accumulated electrons as active sites to lower the energy barrier of rate-determining step of CO_(2)photoreduction,leading to the selective conversion of CO_(2)to CO.Herein,the manipulation of IEF intensity through Cu vacancy concentration regulation of cuprous sulfide photocatalysts for efficient charge separation has been discussed,providing a scientific strategy to rationally improve photocata lytic performances for solar energy conversion.展开更多
基金Project(51564034)supported by the National Natural Science Foundation for Distinguished Regional Scholars,ChinaProject(2015HA019)supported by the Scientific and Technological Leading Talent Program in Yunnan Province,China.
文摘The feasibility of a new method for separating arsenic from arsenic-antimony-bearing dusts using Cu S was put forward,in which Sb was transformed into Sb2O4 and Sb2S3 that stayed in the roasted calcine while As was volatilized in the form of As4O6.The factors such as roasting temperature and Cu S addition amount were studied using XRD,EPMA and SEM-EDS.Cu S has an active effect on the separation of arsenic due to the destruction of(Sb,As)2 O3 structures in the original dust and the simultaneous release of As in the form of As4O6.At a roasting temperature of 400°C and Cu S addition amount of 130%,the volatilization rates of arsenic and antimony reach 97.80 wt.%and 8.29 wt.%,respectively.Further,the high As volatile matter can be used to prepare ferric arsenate after it is oxidized,with this treatment rendering the vapor harmlessness.
基金Project(50371066) supported by the National Natural Science Foundation of China
文摘The ribbons of Cu-Cr alloys with high Cr content (15%- 35%, mass fraction) were prepared by rapid solidification. The microstructures of solidified samples were analyzed by scanning electron microscopy and transmission electron microscopy. The results reveal that a representative liquid phase separation microstructures are observed in Cu75Cr25 ribbons solidified at a cooling rate of about 104K/s. The liquid phase separation is not restrained when the cooling rate is enhanced to about 107K/s. However, the size of Cr particles solidified from Cr-rich liquid or Cr-rich regions in alloy melts could be refined by increasing the cooling rates. The size of Cr particles increases with increasing Cr contents when the ribbons contain 15% to 35%Cr.
基金financially supported by the Postdoctoral Research Foundation of Central South University,China(No.140050037)。
文摘An anion-exchange-based chromatographic separation approach was developed to selectively recover zinc and copper from the high-chlorine raffinate generated in the process of germanium chlorination distillation using 717 resins based on the coordination difference between Zn^(2+)/Cu^(2+)and Cl^(-).The theoretical calculation and spectroscopic analyses suggested that the coordination between Zn^(2+)and Cl^(-)is much stronger than that between Cu^(2+)and Cl^(-),and the Cl-concentration significantly affects Zn(Ⅱ)and Cu(Ⅱ)species.The factors involving Cl-concentration,resin dosage,shaking speed,and temperature were investigated to determine the optimal condition,and the maximum separation factor of Zn/Cu reached as high as 479.2.The results of the adsorption isotherms,adsorption kinetics,SEM,FTIR,and XPS analyses indicated that the process followed the monolayer uniform chemisorption.Through the continuous adsorption experiments,Zn(Ⅱ)and Cu(Ⅱ)in the high-chlorine raffinate were separately recovered,allowing the reuse of residual waste acid and germanium.
基金financially supported by the Yunnan Major Scientific and Technological Projects,China (No.202202AG050015)the National Natural Science Foundation of China (No.51464029)。
文摘The flotation separation of Cu–Fe sulfide minerals at low alkalinity can be achieved using selective depressants.In the flotation system of Cu–Fe sulfide minerals,depressants usually preferentially interact with the pyrite surface to render the mineral surface hydrophilic and hinder the adsorption of the collector.This review summarizes the advances in depressants for the flotation separation of Cu–Fe sulfide minerals at low alkalinity.These advances include use of inorganic depressants (oxidants and sulfur–oxygen compounds),natural polysaccharides (starch,dextrin,konjac glucomannan,and galactomannan),modified polymers (carboxymethyl cellulose,polyacrylamide,lignosulfonate,and tricarboxylate sodium starch),organic acids (polyglutamic acid,sodium humate,tannic acid,pyrogallic acid,salicylic acid,and lactic acid),sodium dimethyl dithiocarbamate,and diethylenetriamine.The potential application of specific inorganic and organic depressants in the flotation separation of Cu–Fe sulfide minerals at low alkalinity is reviewed.The advances in the use of organic depressants with respect to the flotation separation of Cu–Fe sulfide minerals are comprehensively detailed.Additionally,the depression performances and mechanisms of different types of organic depressants on mineral surfaces are summarized.Finally,several perspectives on depressants vis-à-vis flotation separation of Cu–Fe sulfide minerals at low alkalinity are proposed.
文摘The effects of Ni addition on the liquid phase separation and giant magnetoresi stance (GMR) of Cu Co alloys were discussed. The results reveal that Ni additio n can partially restrain the liquid phase separation of Cu Co alloys, resultin g in a decrease of volume fraction for the Co rich particles separated from the liquid phase and in refined microstructures. The composition analyses indicate t hat Ni is dissolved in both the Co rich and the Cu rich phases, but Ni content in the Co rich phase is much higher than that in the Cu matrix. At the same ti me, Ni addition enhance the solubility between Cu and Co, especially Cu in Co s olid solution. Ni alloying into Cu Co alloys can fully prevent the liquid phase separation during melt spinning, which is very beneficial to improve GMR of Cu Co alloys.
基金supported by the Natural Science Foundation of China (Grant No.50771084)the Natural Science Foundation of the Education Department of Jiangsu province,China (Grant No.09KJB430004)
文摘The homogeneous liquid was separated into two phases, （Fe, Co）-rich LI and Cu-rich L2, once the melt was undercooled below a liquid-phase separation temperature Tsep. If the duration from Tsep to Tsl （solidification temperature of LI phase）, termed the liquid-phase separation interval Δt, exceeded a critical value, an eggtype structure was observed. By utilizing differential thermal analyses （DTA）, the solidification process of the undercooled Fe-Co-Cu alloys was studied. Additionally, an immiscible boundary was obtained, which was a convex parabola with a symmetrical axis of XCu=0.52. Depending on the relative amounts of LI and L2, the minor phase was nucleated firstly to form liquid droplets and separated from the original liquids at the beginning of liquid-phase separation.
基金financially supported by the Postdoctoral Science Foundation of China (No.2014M560802)the Natural Science Foundation of Education Department of Shaanxi Provincial Government (No.16JK1755)the State Key Laboratory of Chemical Engineering (No.SKL-ChE-16A04)
文摘Cu（OH）2 nanowires were prepared and incorporated into poly（vinylidene fluoride）（PVDF） to fabricate Cu（OH）2-PVDF ultrafiltration（UF） membrane via immersion precipitation phase inversion process. The effect of Cu（OH）2 nanowires on the morphology of membranes was investigated by X-ray photoelectron spectroscopy（XPS）, Fourier transform infrared（FTIR） spectroscopy, atomic force microscopy（AFM）, scanning electron microscopy（SEM） and X-ray diffraction（XRD） measurements. The results showed that all the Cu（OH）2-PVDF membranes had wider fingerlike pore structure and better hydrophilicity, smoother surface than pristine PVDF membrane due to the incorporation of Cu（OH）2 nanowires. In addition, water flux and bovine serum albumin（BSA） rejection were also measured to investigate the filtration performance of membranes. The results indicated that all the Cu（OH）2-PVDF membranes had high water flux, outstanding BSA rejection and excellent antifouling properties. It is worth mentioning that the optimized performance could be obtained when the Cu（OH）2 nanowires content reached 1.2 wt%. Furthermore, the membrane with 1.2 wt% Cu（OH）2 nanowires showed outstanding oil-water emulsion separation capability.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.11874356,11904039,51772035 and 52071041)the Project for Fundamental and Frontier Research in Chongqing(Nos.cstc2019jcyjjqX0002 and cstc2020jcyj-msxmX0777)the Fundamental Research Funds for the Central Universities(No.106112016CDJZR308808).The work conducted at Chongqing Institute of Green and Intelligent Technology(Chinese Academy of Sciences)is also supported by Key Research Program of Frontier Sciences,CAS(No.QYZDB-SSWSLH016).
文摘Hydrogen,with the merits of zero emissions and high energy density,is one of the promising green energy sources.Seeking for high efficiency and low-cost catalysts is one of the key issues for hydrogen evolution and its practical applications.Nano-structured metal cocatalysts are widely used to improve the photocatalytic performance via surface electronic structure/properties optimization of the catalyst.Herein,we report ultra-fine(*1 nm)Cu clusters decorated hydrangea-like TiO_(2)systems for photocatalytic hydrogen evolution.The pristine hydrangea-like TiO_(2)support shows a promising performance of hydrogen evolution(1.8 mmol·h^(-1)·g^(-1)),which is*10.7 times higher than that of the commercial P25(168 lmol·h^(-1)·g^(-1)).After ultra-fine Cu clusters decoration,a maximal hydrogen evolution performance(3.7 mmol·h^(-1)·g^(-1))is achieved in the optimized system 6Cu–TiO_(2)(6 wt%).Experimental and theoretical studies demonstrate that the ultra-fine Cu clusters decoration could promote the charge separation and transfer process effectively.The Cu clusters also act as reaction sites for reduction of H_(2)O to H2.These results are of great importance for the study of Cu-based co-catalyst systems and also shed light on the development of other non-noble metal co-catalysts in photocatalysis hydrogen evolution.
基金Projects(51471084,61475117)supported by the National Natural Science Foundation of ChinaProject(13ZCZDGX01109)supported by Tianjin Municipal Science and Technology Commission of ChinaProject(20122BBE500031)supported by the Key Technology Project of Jiangxi Province in China
文摘To select the proper composition and obtain an overall material?microstructure?property relationship for Cu?Fe alloy, theeffect of Fe content on microstructure and properties of Cu?Fe-based composite coatings by laser induction hybrid rapid claddingwas investigated. Microstructure characterization of the composite coatings was tested utilizing SEM, XRD and EDS. Microhardnessmeasurement was executed to evaluate the mechanical properties of the composite coatings. The results show that for low Fe content,the composite coating presents a feature that Fe-rich equiaxed dendrites are embedded in the Cu-rich matrix. With increasing Fecontent, the Fe-rich particles are dispersed in the Cu-rich matrix. With further increasing Fe content, large amounts of Cu-richparticles are homogeneously dispersed in the interdendrite of the Fe-rich matrix. Correspondingly, the average microhardness of thecomposite coatings increases gradually with the increase of Fe content and the microhardness of Cu14.5Fe83Si2C0.5 coating is muchtwice higher than that of the substrate.
基金supported by the National Natural Science Foundation of China(52200123)the Open Project of Key Laboratory of Green Chemical Engineering Process of Ministry of Education(GCP2022007)the Scientific Research and Innovation Team Program of Sichuan University of Science and Engineering(SUSE652A014)。
文摘Although the internal electric field(IEF)of photocatalysts is acknowledged as a potent driving force for photocharge separation,modulating the IEF intensity to achieve enhanced photocatalytic performances remains a challenge.Herein,cuprous sulfide nanosheets with different Cu vacancy concentration were employed to study IEF modulation and corresponding direct charge transfer.Among the samples,Cu_(1.8)S nanosheets possessed intensified IEF intensity compared with those of Cu_(2)S and Cu_(1.95)S nanosheets,suggesting that an enhanced IEF intensity could be achieved by introducing more Cu vacancies.This intensified IEF of Cu_(1.8)S nanosheets induced numerous photogenerated electrons to migrate to its surface,and the dissociative electrons were then captured by Cu vacancies,resulting in efficient charge separation spatially.In addition,the Cu vacancies on Cu_(1.8)S nanosheets accumulated electrons as active sites to lower the energy barrier of rate-determining step of CO_(2)photoreduction,leading to the selective conversion of CO_(2)to CO.Herein,the manipulation of IEF intensity through Cu vacancy concentration regulation of cuprous sulfide photocatalysts for efficient charge separation has been discussed,providing a scientific strategy to rationally improve photocata lytic performances for solar energy conversion.
