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
1.Objective.The Yidun arc within the Tethys-Himalaya metallogenic belt formed during the westward subduction of the Ganzi-Litang Ocean(237-206 Ma)during the Indosinian period,and then underwent the evolution stages of...1.Objective.The Yidun arc within the Tethys-Himalaya metallogenic belt formed during the westward subduction of the Ganzi-Litang Ocean(237-206 Ma)during the Indosinian period,and then underwent the evolution stages of the collisional orogeny(206-138 Ma)and the post-collisional orogeny(135-75 Ma).In recent years,a series of large and medium-sized Late Yanshanian intracontinental porphyry-skarn Mo-Cu-W deposits have been discovered in the southern part of the Yidun arc,including Xiuwacu,Relin,Hongshan,Tongchanggou,and Donglufang(Fig.1a).展开更多
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
A separation method for W and Mo from peroxoacids solution by thermal decomposition wasstudied. Thermal decomposition of peroxotungstic acid and peroxomolybdic acid was investigated respectively. The results confirmed...A separation method for W and Mo from peroxoacids solution by thermal decomposition wasstudied. Thermal decomposition of peroxotungstic acid and peroxomolybdic acid was investigated respectively. The results confirmed that peroxomolybdic acid showed a preferable stability compared with peroxotungstic acid. This thermal stability difference was the basic principle of theseparationof W and Mo. Experiments were performed to study the effects of temperature, stirring speed, free acid concentration and Mo concentration on the separation efficiency. The results indicated that peroxotungstic acid decomposed into tungstic acid（H2WO4） and precipitated selectively,while Mo was rejected in aqueous solution,realizing good separation of W and Mo. The separation factorof W and Moreached 112 under the studied conditions, which indicated that this method has potential for use in separating W and Mo.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
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.
基金jointly supported by the Selection Project of High-level Scientific and Technological Talents and Innovative Teams Project in Yunnan Province(202305AT350004-4)the National Natural Science Foundation of China(42362010 and 42464005)+3 种基金the Field Scientific Observation and Research Station of Mountain Agroecosystem in the Lower Reaches of Nujiang River,Yunnan Province(202305AM340031)the Yunnan Provincial Department of Education Science Research Fund Project(2025J0983)the Wen Bang-chun Academician Workstation in Yunnan Province(202205AF150032)the Undergraduate Innovative Training Program(2310603235).
文摘1.Objective.The Yidun arc within the Tethys-Himalaya metallogenic belt formed during the westward subduction of the Ganzi-Litang Ocean(237-206 Ma)during the Indosinian period,and then underwent the evolution stages of the collisional orogeny(206-138 Ma)and the post-collisional orogeny(135-75 Ma).In recent years,a series of large and medium-sized Late Yanshanian intracontinental porphyry-skarn Mo-Cu-W deposits have been discovered in the southern part of the Yidun arc,including Xiuwacu,Relin,Hongshan,Tongchanggou,and Donglufang(Fig.1a).
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(51334008)supported by the National Natural Science Foundation of ChinaProject(2010FJ1011)supported by the Key Program of Science and Technology of Hunan Province,China
文摘A separation method for W and Mo from peroxoacids solution by thermal decomposition wasstudied. Thermal decomposition of peroxotungstic acid and peroxomolybdic acid was investigated respectively. The results confirmed that peroxomolybdic acid showed a preferable stability compared with peroxotungstic acid. This thermal stability difference was the basic principle of theseparationof W and Mo. Experiments were performed to study the effects of temperature, stirring speed, free acid concentration and Mo concentration on the separation efficiency. The results indicated that peroxotungstic acid decomposed into tungstic acid（H2WO4） and precipitated selectively,while Mo was rejected in aqueous solution,realizing good separation of W and Mo. The separation factorof W and Moreached 112 under the studied conditions, which indicated that this method has potential for use in separating W and Mo.
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 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.
