Although azurite is one of the most important copper oxide minerals,the recovery of this mineral via sulfidization-xanthate flotation is typically unsatisfactory.The present work demonstrated the enhanced sulfidizatio...Although azurite is one of the most important copper oxide minerals,the recovery of this mineral via sulfidization-xanthate flotation is typically unsatisfactory.The present work demonstrated the enhanced sulfidization of azurite surfaces using ammonia phosphate((NH_(4))_(3)PO_(4)) together with Na_(2)S,based on micro-flotation experiments,time-of-flight secondary ion mass spectrometry(ToF-SIMS),X-ray photoelectron spectroscopy(XPS),zeta-potential measurements,contact angle measurements,Fourier-transform infrared(FT-IR)spectroscopy,and ultraviolet-visible(UV-Vis)spectroscopy.Micro-flotation experiments showed that the floatability of azurite was increased following the simultaneous addition of(NH_(4))_(3)PO_(4)and Na_(2)S.ToF-SIMS and XPS analyses demonstrated the formation of a high content of S species on the azurite surface and an increase in the number of Cu(I)species after exposure to(NH_(4))_(3)PO_(4)and Na_(2)S,compared with the azurite-Na_(2)S system.The zeta potential of azurite particles was negatively shifted and the contact angle on the azurite surface was increased with the addition of(NH_(4))_(3)PO_(4)prior to Na_(2)S.These results indicate that treatment with(NH_(4))_(3)PO_(4) enhances the sulfidization of azurite surfaces,which in turn promotes xanthate attachment.FT-IR and UV-Vis analyses confirmed that the addition of(NH_(4))_(3)PO_(4) increased the adsorption of xanthate with reducing the consumption of xanthate during the azurite flotation process.Thus,(NH_(4))_(3)PO_(4) has a beneficial effect on the sulfidization flotation of azurite.展开更多
Bayan Obo rare earth mine is the largest light rare earth resource worldwide,primarily extracts rare earth elements(REEs)from mixed RE concentrates with bastnaesite and monazite.Nevertheless,the adoption of the concen...Bayan Obo rare earth mine is the largest light rare earth resource worldwide,primarily extracts rare earth elements(REEs)from mixed RE concentrates with bastnaesite and monazite.Nevertheless,the adoption of the concentrated sulfuric acid roasting metallurgical process has resulted in damage to the environment.Therefore,this paper adopted the method of selective mineral phase transformation(MPT)followed by enhanced micro-flotation.By determining the optimal MPT co nditions,the flotation recovery of bastnaesite-roasted products by the collector(phthalic acid,PA)is improved,and the enhanced separation of bastnaesite with monazite is realized.The results show that with the increase of roasting temperature and time,the bastnaesite decomposition product is CeOF and monazite does not change significantly.Subsequent micro-flotation exhibits a gradual decline in the PA consumption of bastnaesiteroasted products,while the flotation recovery of monazite-roasted products remains poor.The artificial mixed ore experiments result in a CeOF foam product with a content of 94.14%and a recovery of 85.80%,and a monazite tank product with a content of 73.53%and a recovery of 87.87%.Compared with the preroasting ore,the surface and interior of bastnaesite-roasted products develop numerous cracks and porosities,and no obvious structural damage is observed in monazite-roasted particles.As the roasting temperature increases,the mineral particles undergo recrystallization or closure,reducing the specific surface area of bastnaesite-roasted products and enhancing hydrophobicity,leading to diminished PA consumption.Fourier transform infrared and other flotation-relation tests show that PA is chemisorbed on the surface of CeOF.The MPT conditions are optimized in this study,which provides a reference for further advancing the efficient separation of bastnaesite and monazite.展开更多
The limited active sites on the smithsonite surface pose significant challenges to the interaction between collectors and the mineral surface,resulting in suboptimal flotation recovery.This study investigates the infl...The limited active sites on the smithsonite surface pose significant challenges to the interaction between collectors and the mineral surface,resulting in suboptimal flotation recovery.This study investigates the influences of Pb^(2+)and Cu^(2+)on the reactivity,sulfidized components,and collector adsorption on the sulfidized smithsonite surface.Flotation results demonstrated that metal ions significantly improved the flotation behavior of sulfidized smithsonite.With Cu^(2+)or Pb^(2+)activation,the flotation recovery of sulfidized smithsonite reached 80.42%and 84.52%,respectively.Notably,surface activation was further enhanced in the Cu-Pb co-activation system,achieving a flotation recovery of 97.69%.Xray photoelectron spectroscopy(XPS)and time-of-flight secondary ion mass spectroscopy(ToF-SIMS)confirmed an increase in sulfidization products on the smithsonite surface following activation with either Pb^(2+)or Cu^(2+),with further enhancement observed in the Cu-Pb co-activation system.Atomic force microscope(AFM)and scanning electron microscope(SEM)revealed morphological changes and variations in elemental content,demonstrating the formation of substantial Cu and Pb sulfidized components on the smithsonite surface in the Cu-Pb co-activation system.Molecular dynamics simulations indicated that the relative concentrations of HS-and metal ions were higher near the smithsonite in the Cu-Pb co-activation system than in the single metal ion activation system.The improved adsorption behavior of the collector on the sulfidized smithsonite surface following Cu-Pb co-activation was confirmed through Fourier transform infrared(FTIR)analysis,adsorption measurements,and contact angle tests.Results reveal that Cu-Pb coactivation remarkably enhances potassium pentyl xanthate(KAX)adsorption on the sulfidized smithsonite surface,providing an innovative approach for improving smithsonite flotation.展开更多
基金supported by the Yunnan Fundamental Research Projects,China(No.202101BE070001-009)Ten Thousand Talent Plans for Young Top-notch Talents of Yunnan Province,China(No.YNWR-QNBJ-2018-051).
文摘Although azurite is one of the most important copper oxide minerals,the recovery of this mineral via sulfidization-xanthate flotation is typically unsatisfactory.The present work demonstrated the enhanced sulfidization of azurite surfaces using ammonia phosphate((NH_(4))_(3)PO_(4)) together with Na_(2)S,based on micro-flotation experiments,time-of-flight secondary ion mass spectrometry(ToF-SIMS),X-ray photoelectron spectroscopy(XPS),zeta-potential measurements,contact angle measurements,Fourier-transform infrared(FT-IR)spectroscopy,and ultraviolet-visible(UV-Vis)spectroscopy.Micro-flotation experiments showed that the floatability of azurite was increased following the simultaneous addition of(NH_(4))_(3)PO_(4)and Na_(2)S.ToF-SIMS and XPS analyses demonstrated the formation of a high content of S species on the azurite surface and an increase in the number of Cu(I)species after exposure to(NH_(4))_(3)PO_(4)and Na_(2)S,compared with the azurite-Na_(2)S system.The zeta potential of azurite particles was negatively shifted and the contact angle on the azurite surface was increased with the addition of(NH_(4))_(3)PO_(4)prior to Na_(2)S.These results indicate that treatment with(NH_(4))_(3)PO_(4) enhances the sulfidization of azurite surfaces,which in turn promotes xanthate attachment.FT-IR and UV-Vis analyses confirmed that the addition of(NH_(4))_(3)PO_(4) increased the adsorption of xanthate with reducing the consumption of xanthate during the azurite flotation process.Thus,(NH_(4))_(3)PO_(4) has a beneficial effect on the sulfidization flotation of azurite.
基金Project supported by the National Key R&D Program of China(2022YFC2905800)the National Natural Science Foundation of China(52174242)the National Youth Talent Support Program(QNBJ-2023-03)。
文摘Bayan Obo rare earth mine is the largest light rare earth resource worldwide,primarily extracts rare earth elements(REEs)from mixed RE concentrates with bastnaesite and monazite.Nevertheless,the adoption of the concentrated sulfuric acid roasting metallurgical process has resulted in damage to the environment.Therefore,this paper adopted the method of selective mineral phase transformation(MPT)followed by enhanced micro-flotation.By determining the optimal MPT co nditions,the flotation recovery of bastnaesite-roasted products by the collector(phthalic acid,PA)is improved,and the enhanced separation of bastnaesite with monazite is realized.The results show that with the increase of roasting temperature and time,the bastnaesite decomposition product is CeOF and monazite does not change significantly.Subsequent micro-flotation exhibits a gradual decline in the PA consumption of bastnaesiteroasted products,while the flotation recovery of monazite-roasted products remains poor.The artificial mixed ore experiments result in a CeOF foam product with a content of 94.14%and a recovery of 85.80%,and a monazite tank product with a content of 73.53%and a recovery of 87.87%.Compared with the preroasting ore,the surface and interior of bastnaesite-roasted products develop numerous cracks and porosities,and no obvious structural damage is observed in monazite-roasted particles.As the roasting temperature increases,the mineral particles undergo recrystallization or closure,reducing the specific surface area of bastnaesite-roasted products and enhancing hydrophobicity,leading to diminished PA consumption.Fourier transform infrared and other flotation-relation tests show that PA is chemisorbed on the surface of CeOF.The MPT conditions are optimized in this study,which provides a reference for further advancing the efficient separation of bastnaesite and monazite.
基金supported by National Natural Science Foundation of China(No.52264026)Yunnan Fundamental Research Projects(No.202301AW070018)
文摘The limited active sites on the smithsonite surface pose significant challenges to the interaction between collectors and the mineral surface,resulting in suboptimal flotation recovery.This study investigates the influences of Pb^(2+)and Cu^(2+)on the reactivity,sulfidized components,and collector adsorption on the sulfidized smithsonite surface.Flotation results demonstrated that metal ions significantly improved the flotation behavior of sulfidized smithsonite.With Cu^(2+)or Pb^(2+)activation,the flotation recovery of sulfidized smithsonite reached 80.42%and 84.52%,respectively.Notably,surface activation was further enhanced in the Cu-Pb co-activation system,achieving a flotation recovery of 97.69%.Xray photoelectron spectroscopy(XPS)and time-of-flight secondary ion mass spectroscopy(ToF-SIMS)confirmed an increase in sulfidization products on the smithsonite surface following activation with either Pb^(2+)or Cu^(2+),with further enhancement observed in the Cu-Pb co-activation system.Atomic force microscope(AFM)and scanning electron microscope(SEM)revealed morphological changes and variations in elemental content,demonstrating the formation of substantial Cu and Pb sulfidized components on the smithsonite surface in the Cu-Pb co-activation system.Molecular dynamics simulations indicated that the relative concentrations of HS-and metal ions were higher near the smithsonite in the Cu-Pb co-activation system than in the single metal ion activation system.The improved adsorption behavior of the collector on the sulfidized smithsonite surface following Cu-Pb co-activation was confirmed through Fourier transform infrared(FTIR)analysis,adsorption measurements,and contact angle tests.Results reveal that Cu-Pb coactivation remarkably enhances potassium pentyl xanthate(KAX)adsorption on the sulfidized smithsonite surface,providing an innovative approach for improving smithsonite flotation.
