In recent years,with the rapid developme nt of the econo my and society,pollution of valuable metal ions in wastewater has become a major challenge to environmental sustainability.In order to solve the pollution cause...In recent years,with the rapid developme nt of the econo my and society,pollution of valuable metal ions in wastewater has become a major challenge to environmental sustainability.In order to solve the pollution caused by metal ions,researchers have conducted continuous re searches and explored various re mediation methods.Crown ether has attracted great attention because of its ionic radius and cavity size matching well with metal ions,which makes it have the ability to selectively complex metal ions.This unique property enables the directed removal and recovery of metal ions and makes crown ethers increasingly popular in extraction and separation processes.In this paper,the research progress of crown ethers in the extraction and separation of valuable metal ions was reviewed,with emphasis on the principles,extraction systems and the key factors affecting the extraction process.This study can provide some technical support for the application of separation and extraction of valuable metal ions by crown ether.展开更多
Ionic liquids as green solvents have shown important application in the extraction and separation of nonferrous metals.The new application perspective,the important fundamental and the applied studies of the extractio...Ionic liquids as green solvents have shown important application in the extraction and separation of nonferrous metals.The new application perspective,the important fundamental and the applied studies of the extraction and separation of nonferrous metals in ionic liquids,including the dissolution and corrosion of metal and metal oxide,hydrometallurgy of chalcopyrite and metallic oxidized ore,and extraction and separation of metal ions,are introduced.展开更多
Recovery processes of secondary resources usually encounter problems because of the diverse com- positions of wastes. To enhance the applicability of tradi- tional hydrometallurgical process toward secondary resources...Recovery processes of secondary resources usually encounter problems because of the diverse com- positions of wastes. To enhance the applicability of tradi- tional hydrometallurgical process toward secondary resources, the adjustment of components is necessary. In traditional hydrometallurgical separation, precipitation and complexation are extensively used. However, their com- bination as a specific metal separation method has not yet been studied in detail. This approach is very promising for solving problems caused by changeable components during recycling processes of secondary resources. This paper reviews the effects of precipitation and complexation in metal separation processes, and a metal separation method system of ＂complexation-precipitation＂ developed to adjust the components of secondary resources is introduced.展开更多
Batch experiments were conducted with a heavy metals and arsenic co-contaminated soil from an abandoned mine to evaluate the feasibility of a remediation technology that combines sieving with soil washing.Leaching of ...Batch experiments were conducted with a heavy metals and arsenic co-contaminated soil from an abandoned mine to evaluate the feasibility of a remediation technology that combines sieving with soil washing.Leaching of the arsenic and heavy metals from the different particle size fractions was found to decrease in the order：〈 0.1,2–0.1,and 〉 2 mm.With increased contact time,the concentration of heavy metals in the leachate was significantly decreased for small particles,probably because of adsorption by the clay soil component.For the different particle sizes,the removal efficiencies for Pb and Cd were75%–87%,and 61%–77% for Zn and Cu,although the extent of removal was decreased for As and Cr at 〈 45%.The highest efficiency by washing for Pb,Cd,Zn,and As was from the soil particles 〉 2 mm,although good metal removal efficiencies were also achieved in the small particle size fractions.Through SEM-EDS observations and correlation analysis,the leaching regularity of the heavy metals and arsenic was found to be closely related to Fe,Mn,and Ca contents of the soil fractions.The remediation of heavy metal-contaminated soil by sieving combined with soil washing was proven to be efficient,and practical remediation parameters were also recommended.展开更多
Na_(2)S,Na_(2)CO_(3),FeO,FeS and carbon were used to regulate the properties of slag or metal fractions,and their effects on metal growth and metal–slag separation behavior were investigated.The growth of ferronickel...Na_(2)S,Na_(2)CO_(3),FeO,FeS and carbon were used to regulate the properties of slag or metal fractions,and their effects on metal growth and metal–slag separation behavior were investigated.The growth of ferronickel grains can be enhanced by adding these additives,and Na_(2)S was the most effective.Na_(2)S,Na_(2)CO_(3) and FeO mainly affected the properties of slag,while carbon and FeS affected the metal fraction.The onset temperature of metal–slag separation was 1297℃ for the sample without additive,which was decreased to 1123 and 1101℃ after adding 3.30 wt.%Na_(2)S and 4.47 wt.%Na_(2)CO_(3),respectively.The onset temperature of metal–slag separation was mainly controlled by the slag fraction.The average apparent activation energy of metal grain growth was 125.32 kJ/mol without additive,and it decreased obviously after adding different additives.Na_(2)S also had the most remarkable effect on the decrease in activation energy.展开更多
IBC Advanced Technologies’ Molecular Recognition Technology(MRT) SuperLig products selectively and rapidly bind with target species enabling their selective removal from solutions.The MRT process can produce a high p...IBC Advanced Technologies’ Molecular Recognition Technology(MRT) SuperLig products selectively and rapidly bind with target species enabling their selective removal from solutions.The MRT process can produce a high purity separation product of maximum added value at a competitive cost.SuperLig products have high selectivity for many target species which can include metal ions,anions,and neutral molecules.In operation,the SuperLig product is first placed in a packed column.A solution containing a mixture of the target species and other chemical species is then passed through the column.The target species is removed selectively by the SuperLig product,the column is washed to remove residual feed solution,and the target species is recovered by a minimal quantity of eluent.The result is a pure and concentrated species that can be kept for its value or disposed of safely.The process is environmentally and ecologically friendly with no organic solvents being used.This paper provides a review of some examples of applications of MRT to separations of interest to the Chinese metallurgical industry.Included are several applications of MRT,including Pd separations from Pt metal refinery streams and low-grade spent catalyst wastes,Rh recovery from spent auto catalyst and other feeds,Re removal from selected impurity ions,Cd removal from Co electrolyte,Bi removal from Cu electrolyte,In and Ge separations from difficult matrices,and removal of bivalent first transition series and other metal ions from acid mine drainage(Berkeley Pit,Montana).Finally,the potential application of MRT to separations involving the recovery of rare earth metals and Li from low-level waste solutions and end-of-life products is discussed.展开更多
Slag/metal separation process of the highly reduced oolitic high-phosphorus iron ore fines was investigated. Samples were prepared using the reduced ore fines （metallization rate： 88%） and powder additives of CaO a...Slag/metal separation process of the highly reduced oolitic high-phosphorus iron ore fines was investigated. Samples were prepared using the reduced ore fines （metallization rate： 88%） and powder additives of CaO and Na2CO3. Slag/metal separation behavior tests were conducted using a quenching method and the obtained metal parts were subjected to direct observation as well as microstructure examination with SEM and EDS; iron recovery and phosphorus distribution tests were conducted using a Si-Mo high temperature furnace and the obtained metal parts were examined by ICP-AES analysis and mass measurement. Thermodynamic calculation using coexistence theory of slag structure was also performed. Results show that temperature for slag/metal separation must be higher than 1823 K and a satisfying slag/metal separation of the highly reduced ore fines needs at least 4 min; phosphorus con- tent of hot metal is mainly determined by thermodynamics; temperature of 1823-1873 K and Na2CO3 mixing ratio of about 3 % are adequate for controlling phosphorus content to be less than 0.3 mass% in hot metal; temperature, time and Na2CO3 mixing ratio do not have significant effect on iron recovery, and iron recovery rate could be higher than 80% as long as a good slag/metal separation result is obtained.展开更多
Chromium slag（CS）has become one of the most hazardous solid waste containing chromium and iron.Based on its characteristics,the technology of reduction roasting and magnetic separation was employed to treat CS.The m...Chromium slag（CS）has become one of the most hazardous solid waste containing chromium and iron.Based on its characteristics,the technology of reduction roasting and magnetic separation was employed to treat CS.The major impurity element of CS is magnesium and it exists in magnesium ferrite phase,which is hard to recover iron in the absence of additives.During reduction roasting,additives（Al2O3and CaF2）could destroy the structure of magnesium ferrite and improve the iron grade and recovery.The final product,i.e.chromium-iron powder,contains 72.54% Fe and 13.56% Cr,with the iron recovery of 80.34% and chromium recovery of 80.70%.展开更多
The smelting-separation process for metallized pellets of vanadium-bearing titanomagnetite concentrates was studied.The influences of smelting temperature,smelting time,and the basicity of the metallized pellet on van...The smelting-separation process for metallized pellets of vanadium-bearing titanomagnetite concentrates was studied.The influences of smelting temperature,smelting time,and the basicity of the metallized pellet on vanadium and iron recovery were investigated.The characteristics of titanium slag were analyzed using X-ray diffraction,energy dispersive spectroscopy,and mineralographic microscopic analysis.The results demonstrate that appropriate increases in smelting temperature and smelting time can improve the vanadium and iron recovery from metallized pellets and are beneficial for the slag-iron separation.Although increasing the basicity of the metallized pellet can considerably improve the vanadium and iron recovery,the TiO;grade of titanium slag was decreased.Under the optimal conditions,90.17% of vanadium and 92.98% of iron in the metallized pellet were recovered,and the TiO;grade of titanium slag was 55.01%.It was found that anosovite,augite,spinel,glassiness,and metallic iron were the main mineral phases of the titanium slag.展开更多
The separation of halogens and recovery of heavy metals from secondary copper smelting(SCS)dust using a sulfating roasting−water leaching process were investigated.The thermodynamic analysis results confirm the feasib...The separation of halogens and recovery of heavy metals from secondary copper smelting(SCS)dust using a sulfating roasting−water leaching process were investigated.The thermodynamic analysis results confirm the feasibility of the phase transformation to metal sulfates and to gaseous HF and HCl.Under the sulfating roasting conditions of the roasting temperature of 250℃ and the sulfuric acid excess coefficient of 1.8,over 74 wt.%of F and 98 wt.%of Cl were volatilized into flue gas.Approximately 98.6 wt.%of Zn and 96.5 wt.%of Cu in the roasting product were dissolved into the leaching solution after the water leaching process,while the leaching efficiencies of Pb and Sn were only 0.12%and 0.22%,respectively.The mechanism studies indicate the pivotal effect of roasting temperature on the sulphation reactions from various metal species to metal sulfates and the salting out reactions from various metal halides to gaseous hydrogen halides.展开更多
Two isomeric metal-organic frameworks(MOFs) with 2-dimensional(2D) and 3-dimensional(3D) topologies both comprised of Cu(Ⅱ) and OTf(OTf = trifluoromethanesulfonate) ions were synthesized and characterized.The CO_2,CH...Two isomeric metal-organic frameworks(MOFs) with 2-dimensional(2D) and 3-dimensional(3D) topologies both comprised of Cu(Ⅱ) and OTf(OTf = trifluoromethanesulfonate) ions were synthesized and characterized.The CO_2,CH_4 and N_2 adsorption properties of the two isomeric MOFs were investigated from 263 K to 298 K at0.1 MPa.The results showed that the 2D MOF exhibited a higher selectivity for CO_2 from CO_2/CH_4 and CH_4from CH_4/N_2 compared to the 3D MOF,even though it possessed a lower surface area and pore volume.The higher adsorption heats of gases on the 2D MOF inferred the strong adsorption potential energy in the layered MOFs.Dynamic separation experiments using CO_2/CH_4 and CH_4/N_2 mixtures on the two MOFs proved that the2 D MOF had a longer elution time than the 3D MOF as well as better separation abilities.展开更多
In recent years,deep eutectic solvents have attracted increasing interest as effective extractants for the separation of both organic substances and metals from various objects.Acid-based deep eutectic solvents are mo...In recent years,deep eutectic solvents have attracted increasing interest as effective extractants for the separation of both organic substances and metals from various objects.Acid-based deep eutectic solvents are most often used as extractants for the extraction of metals.In this work,for the first time,the extraction efficiency of transition metals and rare earth elements(Y,Zr,Nb,La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Hf and Ta)from mining tailings and Na,K,Ca,Mg,Cu,Fe,Mn,Pb,Ba,Ni and Sr from biodiesel samples using acidic deep eutectic solvents and saturated aqueous solutions of the same acids(malonic,malic,tartaric and citric)is compared.For this,deep eutectic solvents based on acids and their aqueous saturated solutions were prepared and studied.The prepared mixtures were analyzed by IR spectroscopy to confirm the formation of eutectic solvents.Properties such as the density and viscosity of the resulting mixtures were also investigated,as this can be of key importance for the efficiency of metal extraction.The extraction of rare earth metals from mining tailings took a long time(up to several days),while the extraction of metals from fuel took no more than 30 min.Atomic emission spectral methods were used as an analysis method.It is shown that the extraction efficiency with aqueous solutions is better than that with eutectic solvents,which casts doubt on the need for deep eutectic solvents use in this area.展开更多
IBC Advanced Technologies' Molecular Recognition Technology(MRT) products,trade named SuperLig,selectively and rapidly bind with target metal ions to remove them from solution.The MRT process can produce a high pu...IBC Advanced Technologies' Molecular Recognition Technology(MRT) products,trade named SuperLig,selectively and rapidly bind with target metal ions to remove them from solution.The MRT process can produce a high purity separation product of maximum added value at low cost.In this paper,applications of MRT in the precious metals industry,including selective commercial separations involving Au,Pd,Pt,Rh,and Ru,are described and discussed.Application of MRT to the analytical determination of precious metals is presented.Potential use of MRT in recovering precious metals from end-of-life(EOL) products is discussed.展开更多
Metal ion-imprintedly crosslinked chitosan resin 1 and resin 2 were prepared by theuse of Cu2+ and Ni2+ as template ions and glutaraldehyde as crosslinking agent, respectively.Through investigation on the adsorption c...Metal ion-imprintedly crosslinked chitosan resin 1 and resin 2 were prepared by theuse of Cu2+ and Ni2+ as template ions and glutaraldehyde as crosslinking agent, respectively.Through investigation on the adsorption capacities and binding constants for Cu2+, Ni2+andCo2+ ions on chitosan resins, resin 1 and resin 2 exhibit the adsorption selectivity for themixture solution of 1:1 Cu2+ and Ni2+ ions. The adsorption selectivity of metal ion-imprintedresins for their template ions is much higher than that of uncrosslinked chitosan resin.展开更多
The structural evolution of Cu_（45）Zr_（45）Ag_（10） metallic glass was investigated by in situ transmission electron microscopy heating experiments. The relationship between phase separation and crystallization wa...The structural evolution of Cu_（45）Zr_（45）Ag_（10） metallic glass was investigated by in situ transmission electron microscopy heating experiments. The relationship between phase separation and crystallization was elucidated. Nucleation and growth-controlled nanoscale phase separation at early stage were seen to impede nanocrystallization, while a coarser phase separation via aggregation of Ag-rich nanospheres was found to promote the precipitation of Cu-rich nanocrystals.Coupling of composition and dynamics heterogeneities was supposed to play a key role during phase separation preceding crystallization.展开更多
The traditional zinc hydro-metallurgy generates a large amount of zinc ferrite residue rich in valuable metals. The separation of iron is crucial for resource recycling of valuable metals in zinc ferrite residue. A no...The traditional zinc hydro-metallurgy generates a large amount of zinc ferrite residue rich in valuable metals. The separation of iron is crucial for resource recycling of valuable metals in zinc ferrite residue. A novel selective reduction roasting？leaching process was proposed to separate zinc and iron from zinc leaching residue which contains zinc ferrite. The thermodynamic analysis was employed to determine the predominant range of Fe3O4 and ZnO during reduction roasting process of zinc ferrite. Based on the result of thermodynamic calculation, we found thatV（CO）/V（CO＋CO2） ratio is a key factor determining the phase composition in the reduction roasting product of zinc ferrite. In the range ofV（CO）/V（CO＋CO2） ratio between 2.68% and 36.18%, zinc ferrite is preferentially decomposed into Fe3O4 and ZnO. Based on thermogravimetric （TG） analysis, the optimal conditions for reduction roasting of zinc ferrite are determined as follows： temperature 700？750 °C, volume fraction of CO 6% and V（CO）/V（CO＋CO2） ratio 30%. Based on the above results, zinc leaching residue rich in zinc ferrite was roasted and the roasted product was leached by acid solution. It is found that zinc extraction rate in zinc leaching residue reaches up to 70% and iron extraction rate is only 18.4%. The result indicates that zinc and iron can be effectively separated from zinc leaching residue.展开更多
The carbothermic reduction of vanadium titanomagnetite concentrate(VTC)with the assistance of Na_(2)CO_(3)was conducted in an argon atmosphere between 1073 and 1473 K.X-ray diffraction and scanning electron microscopy...The carbothermic reduction of vanadium titanomagnetite concentrate(VTC)with the assistance of Na_(2)CO_(3)was conducted in an argon atmosphere between 1073 and 1473 K.X-ray diffraction and scanning electron microscopy were used to investigate the phase transformations during the reaction.By investigating the reaction between VTC and Na_(2)CO_(3),it was concluded that molten Na_(2)CO_(3)broke the structure of titanomagnetite by combining with the acidic oxides(Fe_(2)O_(3),TiO_(2),Al_(2)O_(3),and SiO_(2))to form a Na-rich melt and release FeO and MgO.Therefore,Na_(2)CO_(3)accelerated the reduction rate.In addition,adding Na_(2)CO_(3)also benefited the agglomeration of iron particles and the slag–metal separation by decreasing the viscosity of the slag.Thus,Na_(2)CO_(3)assisted carbothermic reduction is a promising method for treating VTC at low temperatures.展开更多
Lead, zinc, and iron were recovered from jarosite residues using direct reduction followed by magnetic separation. The influence of the coal dosage, reduction temperature, and reduction time on the volatilization rate...Lead, zinc, and iron were recovered from jarosite residues using direct reduction followed by magnetic separation. The influence of the coal dosage, reduction temperature, and reduction time on the volatilization rates of lead and zinc and the metallization rate of iron were investigated. The results show that the volatilization rates of lead and zinc were 96.97% and 99.89%, respectively, and the iron metallization rate was 91.97% under the optimal reduction roasting conditions of a coal dosage of 25.0 wt% and reduction roasting at 1250°C for 60 min. The magnetic concentrate with an iron content of 90.59 wt% and an iron recovery rate of 50.87% was obtained under the optimum conditions in which 96.56% of the reduction product particles were smaller than 37 μm and the magnetic field strength was 24 k A/m. Therefore, the results of this study demonstrate that recovering valuable metals such as lead, zinc, and iron from jarosite residues is feasible using the developed approach.展开更多
The comprehensive utilization of abundant high-boron iron concentrate is of particular significance to Chi- na, and the high-boron iron concentrate has not yet been utilized as a source for boron at an industrial scal...The comprehensive utilization of abundant high-boron iron concentrate is of particular significance to Chi- na, and the high-boron iron concentrate has not yet been utilized as a source for boron at an industrial scale due to its complex mineralogy and fine mineral dissemination. An innovative method was proposed for recovery of boron and iron from high-boron iron concentrate by reduction roasting and magnetic sepa- ration. The effects of reduction temperature and roasting time were investigated and their optimum condi- tions were determined. The mineralogical changes during roasting were characterized by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. The results showed that the pyrrhotite （FeS） contained in the high-boron iron concentrate and the new-formed FeS-Fe solid solution softened or melted at high temperatures owing to their low melting points, and then decreased the metallic iron ratio and accelerated the growth of metallic iron particles. Meanwhile, the magnetite and szaibelyite were converted into metal- lic iron and suanite, respectively. Consequently, boron was readily enriched into the non-magnetic product and the metallic iron was aggregated to the magnetic concentrate by magnetic separation. Boron recovery of 88.6% with corresponding B2O3 content of 14.5% and iron recovery of 95.1% with an iron grade of 92.7% were achieved when high-boron iron concentrate was reduced at 1 125℃ for 150 min. Besides, the boron reactivity of the boron-rich non-magnetic product was up to 80.8%.展开更多
This article presents a new method to obtain local reinforcement in near-surface layers of channels in castings made of a particle-reinforced metal matrix composite in the alternating electromagnetic field generated b...This article presents a new method to obtain local reinforcement in near-surface layers of channels in castings made of a particle-reinforced metal matrix composite in the alternating electromagnetic field generated by an inductor placed inside the channel. In centrifugal casting, the centrifugal force on the particles leads to the formation of composite structures, while in the proposed method, the electromag- netic force field on the particles results in the designed structure of the composite casting. The article reports the experimental verification of this method using an aluminium sleeve reinforced locally with SiC particles at the inner wall.展开更多
基金financially supported by the National Natural Science Foundation of China (52174336)the Natural Science Foundation of Shandong Province (ZR2021MB051)。
文摘In recent years,with the rapid developme nt of the econo my and society,pollution of valuable metal ions in wastewater has become a major challenge to environmental sustainability.In order to solve the pollution caused by metal ions,researchers have conducted continuous re searches and explored various re mediation methods.Crown ether has attracted great attention because of its ionic radius and cavity size matching well with metal ions,which makes it have the ability to selectively complex metal ions.This unique property enables the directed removal and recovery of metal ions and makes crown ethers increasingly popular in extraction and separation processes.In this paper,the research progress of crown ethers in the extraction and separation of valuable metal ions was reviewed,with emphasis on the principles,extraction systems and the key factors affecting the extraction process.This study can provide some technical support for the application of separation and extraction of valuable metal ions by crown ether.
基金Project(50904031) supported by the National Natural Science Foundation of ChinaProject(2008E0049M) supported by the Natural Science Foundation of Yunnan Province,China+1 种基金Project(07Z40082) supported by the Science Foundation of the Education Department of Yunnan Province,ChinaProject(2007-16) supported by the Science Foundation of Kunming University of Science and Technology,China
文摘Ionic liquids as green solvents have shown important application in the extraction and separation of nonferrous metals.The new application perspective,the important fundamental and the applied studies of the extraction and separation of nonferrous metals in ionic liquids,including the dissolution and corrosion of metal and metal oxide,hydrometallurgy of chalcopyrite and metallic oxidized ore,and extraction and separation of metal ions,are introduced.
基金financially supported by the National High-tech R&D Program of China(No.2013AA040208)the National Natural Science Foundation of China(No.51304010)the Beijing Natural Science Foundation(No.2132016)
文摘Recovery processes of secondary resources usually encounter problems because of the diverse com- positions of wastes. To enhance the applicability of tradi- tional hydrometallurgical process toward secondary resources, the adjustment of components is necessary. In traditional hydrometallurgical separation, precipitation and complexation are extensively used. However, their com- bination as a specific metal separation method has not yet been studied in detail. This approach is very promising for solving problems caused by changeable components during recycling processes of secondary resources. This paper reviews the effects of precipitation and complexation in metal separation processes, and a metal separation method system of ＂complexation-precipitation＂ developed to adjust the components of secondary resources is introduced.
基金supported by the National High Technology Research and Development Program of China(863 Program)(No.2012AA06A201)the Science and Technology Project of Beijing(No.Z141100000914011)
文摘Batch experiments were conducted with a heavy metals and arsenic co-contaminated soil from an abandoned mine to evaluate the feasibility of a remediation technology that combines sieving with soil washing.Leaching of the arsenic and heavy metals from the different particle size fractions was found to decrease in the order：〈 0.1,2–0.1,and 〉 2 mm.With increased contact time,the concentration of heavy metals in the leachate was significantly decreased for small particles,probably because of adsorption by the clay soil component.For the different particle sizes,the removal efficiencies for Pb and Cd were75%–87%,and 61%–77% for Zn and Cu,although the extent of removal was decreased for As and Cr at 〈 45%.The highest efficiency by washing for Pb,Cd,Zn,and As was from the soil particles 〉 2 mm,although good metal removal efficiencies were also achieved in the small particle size fractions.Through SEM-EDS observations and correlation analysis,the leaching regularity of the heavy metals and arsenic was found to be closely related to Fe,Mn,and Ca contents of the soil fractions.The remediation of heavy metal-contaminated soil by sieving combined with soil washing was proven to be efficient,and practical remediation parameters were also recommended.
基金support from the National Natural Science Foundation of China(No.51904047)the Fundamental and Frontier Research Project of Chongqing,China(No.cstc2020jcyj-msxmX0515)the State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization,China.
文摘Na_(2)S,Na_(2)CO_(3),FeO,FeS and carbon were used to regulate the properties of slag or metal fractions,and their effects on metal growth and metal–slag separation behavior were investigated.The growth of ferronickel grains can be enhanced by adding these additives,and Na_(2)S was the most effective.Na_(2)S,Na_(2)CO_(3) and FeO mainly affected the properties of slag,while carbon and FeS affected the metal fraction.The onset temperature of metal–slag separation was 1297℃ for the sample without additive,which was decreased to 1123 and 1101℃ after adding 3.30 wt.%Na_(2)S and 4.47 wt.%Na_(2)CO_(3),respectively.The onset temperature of metal–slag separation was mainly controlled by the slag fraction.The average apparent activation energy of metal grain growth was 125.32 kJ/mol without additive,and it decreased obviously after adding different additives.Na_(2)S also had the most remarkable effect on the decrease in activation energy.
文摘IBC Advanced Technologies’ Molecular Recognition Technology(MRT) SuperLig products selectively and rapidly bind with target species enabling their selective removal from solutions.The MRT process can produce a high purity separation product of maximum added value at a competitive cost.SuperLig products have high selectivity for many target species which can include metal ions,anions,and neutral molecules.In operation,the SuperLig product is first placed in a packed column.A solution containing a mixture of the target species and other chemical species is then passed through the column.The target species is removed selectively by the SuperLig product,the column is washed to remove residual feed solution,and the target species is recovered by a minimal quantity of eluent.The result is a pure and concentrated species that can be kept for its value or disposed of safely.The process is environmentally and ecologically friendly with no organic solvents being used.This paper provides a review of some examples of applications of MRT to separations of interest to the Chinese metallurgical industry.Included are several applications of MRT,including Pd separations from Pt metal refinery streams and low-grade spent catalyst wastes,Rh recovery from spent auto catalyst and other feeds,Re removal from selected impurity ions,Cd removal from Co electrolyte,Bi removal from Cu electrolyte,In and Ge separations from difficult matrices,and removal of bivalent first transition series and other metal ions from acid mine drainage(Berkeley Pit,Montana).Finally,the potential application of MRT to separations involving the recovery of rare earth metals and Li from low-level waste solutions and end-of-life products is discussed.
基金Item Sponsored by National Natural Science Foundation of China(51144010)Research Funds from State Key Laboratory of Advanced Metallurgy USTB of China(416020020)
文摘Slag/metal separation process of the highly reduced oolitic high-phosphorus iron ore fines was investigated. Samples were prepared using the reduced ore fines （metallization rate： 88%） and powder additives of CaO and Na2CO3. Slag/metal separation behavior tests were conducted using a quenching method and the obtained metal parts were subjected to direct observation as well as microstructure examination with SEM and EDS; iron recovery and phosphorus distribution tests were conducted using a Si-Mo high temperature furnace and the obtained metal parts were examined by ICP-AES analysis and mass measurement. Thermodynamic calculation using coexistence theory of slag structure was also performed. Results show that temperature for slag/metal separation must be higher than 1823 K and a satisfying slag/metal separation of the highly reduced ore fines needs at least 4 min; phosphorus con- tent of hot metal is mainly determined by thermodynamics; temperature of 1823-1873 K and Na2CO3 mixing ratio of about 3 % are adequate for controlling phosphorus content to be less than 0.3 mass% in hot metal; temperature, time and Na2CO3 mixing ratio do not have significant effect on iron recovery, and iron recovery rate could be higher than 80% as long as a good slag/metal separation result is obtained.
基金Sponsored by National Natural Science Foundation of China(50904001,U1260101)Program for Innovative Research Team in Anhui University of Technology(TD200909)
文摘Chromium slag（CS）has become one of the most hazardous solid waste containing chromium and iron.Based on its characteristics,the technology of reduction roasting and magnetic separation was employed to treat CS.The major impurity element of CS is magnesium and it exists in magnesium ferrite phase,which is hard to recover iron in the absence of additives.During reduction roasting,additives（Al2O3and CaF2）could destroy the structure of magnesium ferrite and improve the iron grade and recovery.The final product,i.e.chromium-iron powder,contains 72.54% Fe and 13.56% Cr,with the iron recovery of 80.34% and chromium recovery of 80.70%.
基金Item Sponsored by National Natural Science Foundation of China(51174122)
文摘The smelting-separation process for metallized pellets of vanadium-bearing titanomagnetite concentrates was studied.The influences of smelting temperature,smelting time,and the basicity of the metallized pellet on vanadium and iron recovery were investigated.The characteristics of titanium slag were analyzed using X-ray diffraction,energy dispersive spectroscopy,and mineralographic microscopic analysis.The results demonstrate that appropriate increases in smelting temperature and smelting time can improve the vanadium and iron recovery from metallized pellets and are beneficial for the slag-iron separation.Although increasing the basicity of the metallized pellet can considerably improve the vanadium and iron recovery,the TiO;grade of titanium slag was decreased.Under the optimal conditions,90.17% of vanadium and 92.98% of iron in the metallized pellet were recovered,and the TiO;grade of titanium slag was 55.01%.It was found that anosovite,augite,spinel,glassiness,and metallic iron were the main mineral phases of the titanium slag.
基金the National Key Research and Development Program of China(No.2019YFC1908400)the National Natural Science Foundation of China(Nos.52174334,52374413)+3 种基金the Jiangxi Provincial Cultivation Program for Academic and Technical Leaders of Major Subjects,China(Nos.20212BCJ23007,20212BCJL23052)the Jiangxi Provincial Natural Science Foundation,China(Nos.20224ACB214009,20224BAB214040)the Double Thousand Plan of Jiangxi Province,China(No.S2021GDQN2970)the Distinguished Professor Program of Jinggang Scholars in Institutions of Higher Learning of Jiangxi Province,China.
文摘The separation of halogens and recovery of heavy metals from secondary copper smelting(SCS)dust using a sulfating roasting−water leaching process were investigated.The thermodynamic analysis results confirm the feasibility of the phase transformation to metal sulfates and to gaseous HF and HCl.Under the sulfating roasting conditions of the roasting temperature of 250℃ and the sulfuric acid excess coefficient of 1.8,over 74 wt.%of F and 98 wt.%of Cl were volatilized into flue gas.Approximately 98.6 wt.%of Zn and 96.5 wt.%of Cu in the roasting product were dissolved into the leaching solution after the water leaching process,while the leaching efficiencies of Pb and Sn were only 0.12%and 0.22%,respectively.The mechanism studies indicate the pivotal effect of roasting temperature on the sulphation reactions from various metal species to metal sulfates and the salting out reactions from various metal halides to gaseous hydrogen halides.
基金Supported by National Natural Science Foundation of China(No.21136007,No.51302184)the National Research Fund for Fundamental Key Projects(No.2014CB260402)
文摘Two isomeric metal-organic frameworks(MOFs) with 2-dimensional(2D) and 3-dimensional(3D) topologies both comprised of Cu(Ⅱ) and OTf(OTf = trifluoromethanesulfonate) ions were synthesized and characterized.The CO_2,CH_4 and N_2 adsorption properties of the two isomeric MOFs were investigated from 263 K to 298 K at0.1 MPa.The results showed that the 2D MOF exhibited a higher selectivity for CO_2 from CO_2/CH_4 and CH_4from CH_4/N_2 compared to the 3D MOF,even though it possessed a lower surface area and pore volume.The higher adsorption heats of gases on the 2D MOF inferred the strong adsorption potential energy in the layered MOFs.Dynamic separation experiments using CO_2/CH_4 and CH_4/N_2 mixtures on the two MOFs proved that the2 D MOF had a longer elution time than the 3D MOF as well as better separation abilities.
基金Project supported by the grant from the President of the Russian Federation(MK-806.2022.1.3)。
文摘In recent years,deep eutectic solvents have attracted increasing interest as effective extractants for the separation of both organic substances and metals from various objects.Acid-based deep eutectic solvents are most often used as extractants for the extraction of metals.In this work,for the first time,the extraction efficiency of transition metals and rare earth elements(Y,Zr,Nb,La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Hf and Ta)from mining tailings and Na,K,Ca,Mg,Cu,Fe,Mn,Pb,Ba,Ni and Sr from biodiesel samples using acidic deep eutectic solvents and saturated aqueous solutions of the same acids(malonic,malic,tartaric and citric)is compared.For this,deep eutectic solvents based on acids and their aqueous saturated solutions were prepared and studied.The prepared mixtures were analyzed by IR spectroscopy to confirm the formation of eutectic solvents.Properties such as the density and viscosity of the resulting mixtures were also investigated,as this can be of key importance for the efficiency of metal extraction.The extraction of rare earth metals from mining tailings took a long time(up to several days),while the extraction of metals from fuel took no more than 30 min.Atomic emission spectral methods were used as an analysis method.It is shown that the extraction efficiency with aqueous solutions is better than that with eutectic solvents,which casts doubt on the need for deep eutectic solvents use in this area.
文摘IBC Advanced Technologies' Molecular Recognition Technology(MRT) products,trade named SuperLig,selectively and rapidly bind with target metal ions to remove them from solution.The MRT process can produce a high purity separation product of maximum added value at low cost.In this paper,applications of MRT in the precious metals industry,including selective commercial separations involving Au,Pd,Pt,Rh,and Ru,are described and discussed.Application of MRT to the analytical determination of precious metals is presented.Potential use of MRT in recovering precious metals from end-of-life(EOL) products is discussed.
文摘Metal ion-imprintedly crosslinked chitosan resin 1 and resin 2 were prepared by theuse of Cu2+ and Ni2+ as template ions and glutaraldehyde as crosslinking agent, respectively.Through investigation on the adsorption capacities and binding constants for Cu2+, Ni2+andCo2+ ions on chitosan resins, resin 1 and resin 2 exhibit the adsorption selectivity for themixture solution of 1:1 Cu2+ and Ni2+ ions. The adsorption selectivity of metal ion-imprintedresins for their template ions is much higher than that of uncrosslinked chitosan resin.
基金supported by the National Natural Science Foundation of China (Grant No. 51101004)the financial support of China Scholarship Council. Z.Q. Liu is gratefulsupport by the IMR SYNL-T.S. Kê Research Fellowship
文摘The structural evolution of Cu_（45）Zr_（45）Ag_（10） metallic glass was investigated by in situ transmission electron microscopy heating experiments. The relationship between phase separation and crystallization was elucidated. Nucleation and growth-controlled nanoscale phase separation at early stage were seen to impede nanocrystallization, while a coarser phase separation via aggregation of Ag-rich nanospheres was found to promote the precipitation of Cu-rich nanocrystals.Coupling of composition and dynamics heterogeneities was supposed to play a key role during phase separation preceding crystallization.
基金Project(2011AA061001)supported by the National High-tech Research and Development Program of ChinaProject(2014FJ1011)supported by the Major Science and Technology Project of Hunan Province,China
文摘The traditional zinc hydro-metallurgy generates a large amount of zinc ferrite residue rich in valuable metals. The separation of iron is crucial for resource recycling of valuable metals in zinc ferrite residue. A novel selective reduction roasting？leaching process was proposed to separate zinc and iron from zinc leaching residue which contains zinc ferrite. The thermodynamic analysis was employed to determine the predominant range of Fe3O4 and ZnO during reduction roasting process of zinc ferrite. Based on the result of thermodynamic calculation, we found thatV（CO）/V（CO＋CO2） ratio is a key factor determining the phase composition in the reduction roasting product of zinc ferrite. In the range ofV（CO）/V（CO＋CO2） ratio between 2.68% and 36.18%, zinc ferrite is preferentially decomposed into Fe3O4 and ZnO. Based on thermogravimetric （TG） analysis, the optimal conditions for reduction roasting of zinc ferrite are determined as follows： temperature 700？750 °C, volume fraction of CO 6% and V（CO）/V（CO＋CO2） ratio 30%. Based on the above results, zinc leaching residue rich in zinc ferrite was roasted and the roasted product was leached by acid solution. It is found that zinc extraction rate in zinc leaching residue reaches up to 70% and iron extraction rate is only 18.4%. The result indicates that zinc and iron can be effectively separated from zinc leaching residue.
基金financially supported by the National Key R&D Program of China(No.2018YFC1900500)the National Natural Science Foundation of China(Nos.21908231,51774260,51804289,and 51904286)+2 种基金the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(No.QYZDJ-SSW-JSC021)the CAS Interdisciplinary Innovation Teamthe Special Project for Transformation of Major Technological Achievements in Hebei Province,China(No.19044012Z)。
文摘The carbothermic reduction of vanadium titanomagnetite concentrate(VTC)with the assistance of Na_(2)CO_(3)was conducted in an argon atmosphere between 1073 and 1473 K.X-ray diffraction and scanning electron microscopy were used to investigate the phase transformations during the reaction.By investigating the reaction between VTC and Na_(2)CO_(3),it was concluded that molten Na_(2)CO_(3)broke the structure of titanomagnetite by combining with the acidic oxides(Fe_(2)O_(3),TiO_(2),Al_(2)O_(3),and SiO_(2))to form a Na-rich melt and release FeO and MgO.Therefore,Na_(2)CO_(3)accelerated the reduction rate.In addition,adding Na_(2)CO_(3)also benefited the agglomeration of iron particles and the slag–metal separation by decreasing the viscosity of the slag.Thus,Na_(2)CO_(3)assisted carbothermic reduction is a promising method for treating VTC at low temperatures.
文摘Lead, zinc, and iron were recovered from jarosite residues using direct reduction followed by magnetic separation. The influence of the coal dosage, reduction temperature, and reduction time on the volatilization rates of lead and zinc and the metallization rate of iron were investigated. The results show that the volatilization rates of lead and zinc were 96.97% and 99.89%, respectively, and the iron metallization rate was 91.97% under the optimal reduction roasting conditions of a coal dosage of 25.0 wt% and reduction roasting at 1250°C for 60 min. The magnetic concentrate with an iron content of 90.59 wt% and an iron recovery rate of 50.87% was obtained under the optimum conditions in which 96.56% of the reduction product particles were smaller than 37 μm and the magnetic field strength was 24 k A/m. Therefore, the results of this study demonstrate that recovering valuable metals such as lead, zinc, and iron from jarosite residues is feasible using the developed approach.
基金the financial support from the National Natural Science Foundation of China (51134002)the Fundamental Research Funds for the Central Universities of China (N140108001 and N150106003)
文摘The comprehensive utilization of abundant high-boron iron concentrate is of particular significance to Chi- na, and the high-boron iron concentrate has not yet been utilized as a source for boron at an industrial scale due to its complex mineralogy and fine mineral dissemination. An innovative method was proposed for recovery of boron and iron from high-boron iron concentrate by reduction roasting and magnetic sepa- ration. The effects of reduction temperature and roasting time were investigated and their optimum condi- tions were determined. The mineralogical changes during roasting were characterized by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. The results showed that the pyrrhotite （FeS） contained in the high-boron iron concentrate and the new-formed FeS-Fe solid solution softened or melted at high temperatures owing to their low melting points, and then decreased the metallic iron ratio and accelerated the growth of metallic iron particles. Meanwhile, the magnetite and szaibelyite were converted into metal- lic iron and suanite, respectively. Consequently, boron was readily enriched into the non-magnetic product and the metallic iron was aggregated to the magnetic concentrate by magnetic separation. Boron recovery of 88.6% with corresponding B2O3 content of 14.5% and iron recovery of 95.1% with an iron grade of 92.7% were achieved when high-boron iron concentrate was reduced at 1 125℃ for 150 min. Besides, the boron reactivity of the boron-rich non-magnetic product was up to 80.8%.
基金supported by the National Science Centre of Poland (Grant No. N508 620940)
文摘This article presents a new method to obtain local reinforcement in near-surface layers of channels in castings made of a particle-reinforced metal matrix composite in the alternating electromagnetic field generated by an inductor placed inside the channel. In centrifugal casting, the centrifugal force on the particles leads to the formation of composite structures, while in the proposed method, the electromag- netic force field on the particles results in the designed structure of the composite casting. The article reports the experimental verification of this method using an aluminium sleeve reinforced locally with SiC particles at the inner wall.
