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
Selective flotation separation of Cu-Zn mixed sulfides has been proven to be difficult. Thus far, researchers have found no satis- factory way to separate Cu-Zn mixed sulfides by selective flotation, mainly because of...Selective flotation separation of Cu-Zn mixed sulfides has been proven to be difficult. Thus far, researchers have found no satis- factory way to separate Cu-Zn mixed sulfides by selective flotation, mainly because of the complex surface and interface interaction mecha- nisms in the flotation solution. Undesired activation occurs between copper ions and the sphalerite surfaces. In addition to recycled water and mineral dissolution, ancient fluids in the minerals are observed to be a new source of metal ions. In this study, significant amounts of ancient fluids were found to exist in Cu-Zn sulfide and gangue minerals, mostly as gas-liquid fluid inclusions. The concentration of copper ions re- leased from the ancient fluids reached 1.02 × 10-6 tool/L, whereas, in the cases of sphalerite and quartz, this concentration was 0.62 ×10-6 mol/L and 0.44 × 10-6 mol/L, respectively. As a result, the ancient fluid is a significant source of copper ions compared to mineral dissolution under the same experimental conditions, which promotes the unwanted activation of sphalerite. Therefore, the ancient fluid is considered to be a new factor that affects the selective flotation separation of Cu-Zn mixed sulfide ores.展开更多
The comprehensive recovery of small amounts of valuable minerals such as gold and base-metal sulfide minerals from a low-grade refractory ore was investigated. The following treatment strategy was applied to a sample ...The comprehensive recovery of small amounts of valuable minerals such as gold and base-metal sulfide minerals from a low-grade refractory ore was investigated. The following treatment strategy was applied to a sample of this ore: gold flotation-gold concen- trate leaching-lead and zinc flotation from the gold concentrate leaching residue. Closed-circuit trials of gold flotation yielded a gold concen- trate that assayed at 40.23 g·t-1 Au with a recovery of 86.25%. The gold concentrate leaching rate was 98.76%. Two variants of lead-zinc flotation from the residue--preferential flotation of lead and zinc and bulk flotation of lead and zinc--were tested using the middling processing method. Foam from the reflotation was returned to the lead rougher flotation or lead-zinc bulk flotation, whereas middlings from reflotation were discarded. Sulfur concentrate was a byproduct. The combined strategy of flotation, leaching, and flotation is recommended for the treatment of this kind of ore.展开更多
The feasibility for modifying the wettability and floatability of sulfideminerals by electron beam irradiation has been studied experimentally. The wettability ofcrystalline pyrite and floatability of some sulfide as ...The feasibility for modifying the wettability and floatability of sulfideminerals by electron beam irradiation has been studied experimentally. The wettability ofcrystalline pyrite and floatability of some sulfide as pyrite, arsenopyrite, chalcopyrite andmarmatite after irradiation were examined by flotation in a modified Hallimond tube. Experimentalresults show that the hydrophobicity of crystalline pyrite enhances with the increase of irradiationdose in a low dose range. And the flotation responses of sulfide minerals on irradiation dose varywith the mineral species and particle size. The floatability of minerals can be regulated byaltering irradiation dose. An explanation for the mechanism has been suggested based on theprinciple of radiation chemistry.展开更多
Groundwater serves as an important water source for residents in and around mining areas.To achieve scientific planning and efficient utilization of water resources in mining areas,it is essential to figure out the ch...Groundwater serves as an important water source for residents in and around mining areas.To achieve scientific planning and efficient utilization of water resources in mining areas,it is essential to figure out the chemical formation process and the ground water sulfur cycle that transpire after the coal mining activities.Based on studies of hydrochemistry and D,^(18)O-H_(2)O,^(34)S-SO_(4)isotopes,this study applied principal component analysis,ion ratio and other methods in its attempts to reveal the hydrogeochemical action and sulfur cycle in the subsidence area of Pingyu mining area.The study discovered that,in the studied area,precipitation provides the major supply of groundwater and the main water chemistry effects are dominated by oxidation dissolution of sulfide minerals as well as the dissolution of carbonate and silicate rocks.The sulfate in groundwater primarily originates from oxidation and dissolution of sulfide minerals in coal-bearing strata and human activities.The mixed sulfate formed by the oxidation of sulfide minerals and by human activities continuously recharges the groundwater,promoting the dissolution of carbonate rock and silicate rock in the process.展开更多
Sulfide minerals are found in porous media in both aerobic and anaerobic environments, they should have a high affinities for certain metals. The relative binding affinities and reaction processes for 10 metal/metallo...Sulfide minerals are found in porous media in both aerobic and anaerobic environments, they should have a high affinities for certain metals. The relative binding affinities and reaction processes for 10 metal/metalloid ions reacting with four sulfide mineral surfaces has been defined.The order of reactivity is chalcocite > pyrite > galena >> sphalerite. For any particular metal and mineral, the greater reactivity occurs in the single-ion metal system except Ag(I) on pyrite and Cu(II) on galena.Both precipitation and adsorption reaction can decrease metal ion mobility on porous media, the order of metal mobility in the presence of the four sulfide minerals is predicted to be: Zn(II), Cd(II) and Ni(II) - mobile; Cu(II), Pb(II), Fe(III), As(III) and Cr(III) - variable mobility and Ag(I) - immobile.MINTEQA1 predictions on metal phase distribution / partitioning compared quite well with those observed experimentally. Solubility product considerations, intrinsic acidity constant of the mineral, EH, pH and the carbonate equilibrium are major factors controlling the phase distribution of metals reacting singularly or in combination with sulfide mineral surfaces.展开更多
Batch adsorption experiment with four sulfide minerals - Chalcocite galena, pyrite and sphalerite - were used to study for the adsorption and desorp-tion behavior of La (III) in the presence of EDTA, a model humic mat...Batch adsorption experiment with four sulfide minerals - Chalcocite galena, pyrite and sphalerite - were used to study for the adsorption and desorp-tion behavior of La (III) in the presence of EDTA, a model humic matter. Linear adsorption was found in all cases.The presence of soluble organic complexing ligand should reduce the mobility of La (III) in porous media and its transport to groundwater in the percolating soil solution. Binding mechanism is proposed to account for this preferential binding behavior.展开更多
Comparative voltammetry and differential double-layer capacitance studies were performed to evaluate interfacial interactions between cnalcopyrite(CuFeS2) and n-isopropyl xanthate(X) in the presence of ammonium bi...Comparative voltammetry and differential double-layer capacitance studies were performed to evaluate interfacial interactions between cnalcopyrite(CuFeS2) and n-isopropyl xanthate(X) in the presence of ammonium bisulfite/39wt%SO2 and caustic starch at different pH values.Raman spectroscopy,Fourier transform infrared(FTIR) spectroscopy,contact angle measurements,and microflotation tests were used to establish the type and extent of xanthate adsorption as well as the species involved under different mineral surface conditions in this study.The results demonstrate that the species that favor a greater hydrophobicity of chalcopyrite are primarily CuX and S^0,whereas oxides and hydroxides of Cu and Fe as well as an excess of starch decrease the hydrophobicity.A conditioning of the mineral surface with ammonium bisulfite/39wt%SO2 at pH 6 promotes the activation of surface and enhances the xanthate adsorption.However,this effect is diminished at pH ≥ 8,when an excess of starch is added during the preconditioning step.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financially supported by the National Natural Science Foundation of China(Nos.51464029,51404119,and 51168020)the Natural Science Foundation of Yunnan Province,China(Nos.2012J08 and 2014Y0845)the Excellent Doctoral Dissertation and Talent Cultivation Foundation of Kunming University of Science and Technology(Nos.41118011 and 201421066)
文摘Selective flotation separation of Cu-Zn mixed sulfides has been proven to be difficult. Thus far, researchers have found no satis- factory way to separate Cu-Zn mixed sulfides by selective flotation, mainly because of the complex surface and interface interaction mecha- nisms in the flotation solution. Undesired activation occurs between copper ions and the sphalerite surfaces. In addition to recycled water and mineral dissolution, ancient fluids in the minerals are observed to be a new source of metal ions. In this study, significant amounts of ancient fluids were found to exist in Cu-Zn sulfide and gangue minerals, mostly as gas-liquid fluid inclusions. The concentration of copper ions re- leased from the ancient fluids reached 1.02 × 10-6 tool/L, whereas, in the cases of sphalerite and quartz, this concentration was 0.62 ×10-6 mol/L and 0.44 × 10-6 mol/L, respectively. As a result, the ancient fluid is a significant source of copper ions compared to mineral dissolution under the same experimental conditions, which promotes the unwanted activation of sphalerite. Therefore, the ancient fluid is considered to be a new factor that affects the selective flotation separation of Cu-Zn mixed sulfide ores.
基金financially supported by the National Natural Science Foundation of China (No. 51504031)
文摘The comprehensive recovery of small amounts of valuable minerals such as gold and base-metal sulfide minerals from a low-grade refractory ore was investigated. The following treatment strategy was applied to a sample of this ore: gold flotation-gold concen- trate leaching-lead and zinc flotation from the gold concentrate leaching residue. Closed-circuit trials of gold flotation yielded a gold concen- trate that assayed at 40.23 g·t-1 Au with a recovery of 86.25%. The gold concentrate leaching rate was 98.76%. Two variants of lead-zinc flotation from the residue--preferential flotation of lead and zinc and bulk flotation of lead and zinc--were tested using the middling processing method. Foam from the reflotation was returned to the lead rougher flotation or lead-zinc bulk flotation, whereas middlings from reflotation were discarded. Sulfur concentrate was a byproduct. The combined strategy of flotation, leaching, and flotation is recommended for the treatment of this kind of ore.
基金the National Natural Science Foundation of China (No.59874002).
文摘The feasibility for modifying the wettability and floatability of sulfideminerals by electron beam irradiation has been studied experimentally. The wettability ofcrystalline pyrite and floatability of some sulfide as pyrite, arsenopyrite, chalcopyrite andmarmatite after irradiation were examined by flotation in a modified Hallimond tube. Experimentalresults show that the hydrophobicity of crystalline pyrite enhances with the increase of irradiationdose in a low dose range. And the flotation responses of sulfide minerals on irradiation dose varywith the mineral species and particle size. The floatability of minerals can be regulated byaltering irradiation dose. An explanation for the mechanism has been suggested based on theprinciple of radiation chemistry.
基金supported by Geological Research Project of the Construction Management Bureau of the Middle Route of the South to North Water Diversion Project(ZXJ/HN/YW/GC-2020037)。
文摘Groundwater serves as an important water source for residents in and around mining areas.To achieve scientific planning and efficient utilization of water resources in mining areas,it is essential to figure out the chemical formation process and the ground water sulfur cycle that transpire after the coal mining activities.Based on studies of hydrochemistry and D,^(18)O-H_(2)O,^(34)S-SO_(4)isotopes,this study applied principal component analysis,ion ratio and other methods in its attempts to reveal the hydrogeochemical action and sulfur cycle in the subsidence area of Pingyu mining area.The study discovered that,in the studied area,precipitation provides the major supply of groundwater and the main water chemistry effects are dominated by oxidation dissolution of sulfide minerals as well as the dissolution of carbonate and silicate rocks.The sulfate in groundwater primarily originates from oxidation and dissolution of sulfide minerals in coal-bearing strata and human activities.The mixed sulfate formed by the oxidation of sulfide minerals and by human activities continuously recharges the groundwater,promoting the dissolution of carbonate rock and silicate rock in the process.
文摘Sulfide minerals are found in porous media in both aerobic and anaerobic environments, they should have a high affinities for certain metals. The relative binding affinities and reaction processes for 10 metal/metalloid ions reacting with four sulfide mineral surfaces has been defined.The order of reactivity is chalcocite > pyrite > galena >> sphalerite. For any particular metal and mineral, the greater reactivity occurs in the single-ion metal system except Ag(I) on pyrite and Cu(II) on galena.Both precipitation and adsorption reaction can decrease metal ion mobility on porous media, the order of metal mobility in the presence of the four sulfide minerals is predicted to be: Zn(II), Cd(II) and Ni(II) - mobile; Cu(II), Pb(II), Fe(III), As(III) and Cr(III) - variable mobility and Ag(I) - immobile.MINTEQA1 predictions on metal phase distribution / partitioning compared quite well with those observed experimentally. Solubility product considerations, intrinsic acidity constant of the mineral, EH, pH and the carbonate equilibrium are major factors controlling the phase distribution of metals reacting singularly or in combination with sulfide mineral surfaces.
文摘Batch adsorption experiment with four sulfide minerals - Chalcocite galena, pyrite and sphalerite - were used to study for the adsorption and desorp-tion behavior of La (III) in the presence of EDTA, a model humic matter. Linear adsorption was found in all cases.The presence of soluble organic complexing ligand should reduce the mobility of La (III) in porous media and its transport to groundwater in the percolating soil solution. Binding mechanism is proposed to account for this preferential binding behavior.
基金supported by Universidad Autónoma de San Luis Potosí(No.PROMEP/UASLP/12/CA15)
文摘Comparative voltammetry and differential double-layer capacitance studies were performed to evaluate interfacial interactions between cnalcopyrite(CuFeS2) and n-isopropyl xanthate(X) in the presence of ammonium bisulfite/39wt%SO2 and caustic starch at different pH values.Raman spectroscopy,Fourier transform infrared(FTIR) spectroscopy,contact angle measurements,and microflotation tests were used to establish the type and extent of xanthate adsorption as well as the species involved under different mineral surface conditions in this study.The results demonstrate that the species that favor a greater hydrophobicity of chalcopyrite are primarily CuX and S^0,whereas oxides and hydroxides of Cu and Fe as well as an excess of starch decrease the hydrophobicity.A conditioning of the mineral surface with ammonium bisulfite/39wt%SO2 at pH 6 promotes the activation of surface and enhances the xanthate adsorption.However,this effect is diminished at pH ≥ 8,when an excess of starch is added during the preconditioning step.