This study aimed to investigate the effect of varying pyrite(Py)content on copper(Cu)in the presence of different regrinding conditions,which were altered using different types of grinding media:iron,ceramic balls,and...This study aimed to investigate the effect of varying pyrite(Py)content on copper(Cu)in the presence of different regrinding conditions,which were altered using different types of grinding media:iron,ceramic balls,and their mixture,followed by flotation in the cleaner stage.The flotation performance of rough Cu concentrate can be improved by changing the regrinding conditions based on the Py content.Scanning electron microscopy,X-ray spectrometry,ethylenediaminetetraacetic acid disodium salt extraction,and X-ray photoelectron spectroscopy studies illustrated that when the Py content was high,the use of iron media in regrinding promoted the generation of hydrophilic Fe OOH on the surface of Py and improved the Cu grade.The ceramic medium with a low Py content prevented excessive Fe OOH from covering the surface of chalcopyrite(Cpy).Electrochemical studies further showed that the galvanic corrosion current of Cpy-Py increased with the addition of Py and became stronger with the participation of iron media.展开更多
This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standar...This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standard system was established for comprehensive quality evaluation of HTD.There were obvious changes in the physicochemical properties,enzyme activities,and volatile flavor components at different storage periods,which affected the sensory evaluation of HTD to a certain extent.The results of high-throughput sequencing revealed significant microbial diversity,and showed that the bacterial community changed significantly more than did the fungal community.During the storage process,the dominant bacterial genera were Kroppenstedtia and Thermoascus.The correlation between dominant microorganisms and quality indicators highlighted their role in HTD quality.Lactococcus,Candida,Pichia,Paecilomyces,and protease activity played a crucial role in the formation of isovaleraldehyde.Acidic protease activity had the greatest impact on the microbial community.Moisture promoted isobutyric acid generation.Furthermore,the comprehensive quality evaluation standard system was established by the entropy weight method combined with multi-factor fuzzy mathematics.Consequently,this study provides innovative insights for comprehensive quality evaluation of HTD during storage and establishes a groundwork for scientific and rational storage of HTD and quality control of sauce-flavor Baijiu.展开更多
Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a collector.Flotation experiments showed that MFA produced a stronger in...Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a collector.Flotation experiments showed that MFA produced a stronger inhibition effect on pyrite than on chalcopyrite.The separation of chalcopyrite from pyrite was realized by introducing 150 mg/L MFA at a pulp pH of approximately 8.0.The copper grade,copper recovery,and separation efficiency were 28.03%,84.79%,and 71.66%,respectively.Surface adsorption tests,zeta potential determinations,and localized electrochemical impedance spectroscopy tests showed that more MFA adsorbed on pyrite than on chalcopyrite,which weakened the subsequent interactions between pyrite and the collector.Atomic force microscope imaging further confirmed the adsorption of MFA on pyrite,and X-ray photoelectron spectroscopy results indicated that hydrophilic Fe-based species on the pyrite surfaces increased after exposure of pyrite to MFA,thereby decreasing the floatability of pyrite.展开更多
To investigate the mechanisms of how nanobubbles enhance the flotation separation performance of galena from pyrite,the effects of nanobubbles on the surface properties of galena and pyrite and the interactions betwee...To investigate the mechanisms of how nanobubbles enhance the flotation separation performance of galena from pyrite,the effects of nanobubbles on the surface properties of galena and pyrite and the interactions between mineral particles and air bubbles were examined in this study.Various analytical techniques,including focused beam reflectance measurement(FBRM),three-phase contact line(TPCL)analysis,atomic force microscopy(AFM),and contact angle measurement,were employed.It has been demonstrated that nanobubbles significantly enhanced the flotation recovery of galena and its flotation selectivity from pyrite,as compared to the conventional flotation process.The preferential formation of nanobubbles on the galena surface,which is more hydrophobic than pyrite surface,further increased the surface hydrophobicity and agglomeration of galena particles.The introduction of nanobubbles into the flotation system also increased in the maximum TPCL length and detachment length between the galena surface and bubbles,contributing to the enhanced flotation efficiency.展开更多
Gold ores in the Jiaozhou region of China are characterized by their abundant reserves,low grade,fine dissemination,and chal-lenges in upgrading.Froth flotation,with xanthate as the collector,is a commonly employed me...Gold ores in the Jiaozhou region of China are characterized by their abundant reserves,low grade,fine dissemination,and chal-lenges in upgrading.Froth flotation,with xanthate as the collector,is a commonly employed method for enriching auriferous pyrite from these ores.This study aimed to develop a more efficient flotation process by utilizing cavitation nanobubbles for a low-grade gold ore.Batch flotation tests demonstrated that nanobubbles significantly enhanced the flotation performance of auriferous pyrite,as evidenced by improved concentrate S and Au grades and their recoveries.The mechanisms underlying this enhancement were explored by investigat-ing surface nanobubble(SNB)formation,bulk nanobubble(BNB)attachment to hydrophobic pyrite surfaces,and nanobubble-induced agglomeration using atomic force microscopy(AFM)and focused beam reflectance measurement(FBRM).The results revealed that nan-obubble coverage on the pyrite surface is a critical factor influencing surface hydrophobicity and agglomeration.SNBs exhibited higher coverage on pyrite surfaces with increased surface hydrophobicity,flow rate,and cavitation time.Similarly,BNB attachment on pyrite surfaces was significantly increased with surface hydrophobicity and cavitation time.Enhanced surface hydrophobicity,along with higher flow rates and cavitation times,promoted pyrite particle agglomeration owing to the increased nanobubble coverage,ultimately leading to improved flotation performance.展开更多
Tin is a critical metal for various industries,making its recovery from low-grade cassiterite ores crucial.This study aimed to optimize the flotation recovery of cassiterite using multi-component collector systems.Sev...Tin is a critical metal for various industries,making its recovery from low-grade cassiterite ores crucial.This study aimed to optimize the flotation recovery of cassiterite using multi-component collector systems.Several collectors were initially selected through micro-flotation tests,leading to the identification of optimal proportions for a four-component collector system(SHA-OHA-SPA-DBIA in a 4:3:2:1 ratio).Molecular dynamics simulations and surface tension tests were used to investigate the micellar behavior of these collectors in aqueous solution.The adsorption characteristics were quantified using microcalorimetry,enabling the determination of collection entropy and changes in Gibbs free energy.The four-component collector system showed the highest entropy change and the most favorable Gibbs free energy,leading to a cassiterite recovery of above 90%at a concentration of 8.0×10^(5)mol/L.Various analytical techniques were employed to systematically characterize the adsorption mechanism.The findings revealed a positive correlation between the adsorption products formed by the multicomponent collectors on the cassiterite surface and the entropy changes.Industrial-scale testing of the high-entropy collector system produced a tin concentrate with an Sn grade of 6.17%and an Sn recovery of 82.43%,demonstrating its substantial potential for practical applications in cassiterite flotation.展开更多
Burial dissolution is a critical diagenetic process influencing ultra-deep carbonate reservoir development and preservation.Artificial carbonate samples with different internal structures were prepared,and high-temper...Burial dissolution is a critical diagenetic process influencing ultra-deep carbonate reservoir development and preservation.Artificial carbonate samples with different internal structures were prepared,and high-temperature and highpressure dissolution kinetic simulations were conducted.The results demonstrate that the intensity of burial dissolution is controlled by temperature and pressure,while tectonic-fluid activity influences the development pattern of burial dissolution,ultimately determining the direction of its differential modification.Extensive burial dissolution is likely to occur primarily at relatively shallow depths,significantly influencing reservoir formation,preservation,modification,and adjustment.The development of faults facilitates the maintenance of the intensity of burial dissolution.The maximum intensity of burial dissolution occurs at the tips and overlap zones of faults and intersections of multiple faults.The larger the scale of the faults,the more conducive it is to the development of burial dissolution.Burial dissolution fosters the formation of fault networks characterized by enhanced reservoir capacity and permeability.Burial dissolution controlled by episodic tectonic-fluid activity is a plausible explanation for forming the Tarim Basin's ultra-deep fault-controlled“stringbead-like”reservoirs.展开更多
Hydrogen-based mineral phase transformation(HMPT)technology has demonstrated its effectiveness in separating iron and enriching rare earths from Bayan Obo refractory ores.However,further research is needed to clarify ...Hydrogen-based mineral phase transformation(HMPT)technology has demonstrated its effectiveness in separating iron and enriching rare earths from Bayan Obo refractory ores.However,further research is needed to clarify the phase composition and floatability of rare earths obtained after HMPT owing to the associated phase transformations.This study explored the mineralogical characteristics and separation behavior of rare earths in HMPT-treated iron tailings.Process mineralogy studies conducted via BGRIMM process mineralogy analysis and X-ray diffraction revealed that the main valuable minerals in the tailings included rare-earth oxides(9.15wt%),monazite(5.31wt%),and fluorite(23.52wt%).The study also examined the impact of mineral liberation and gangue mineral intergrowth on flotation performance.Flotation tests achieved a rare-earth oxide(REO)grade of 74.12wt% with a recovery of 34.17% in open-circuit flotation,whereas closed-circuit flotation resulted in a REO grade of 60.27wt% with a recovery of 73%.Transmission electron microscopy and scanning electron microscopy coupled with energy-dispersive spectroscopy revealed that monazite remained stable during the HMPT process,while bastnaesite was transformed into Ce_(7)O_(12)and CeF_(3),leading to increased collector consumption.Nonetheless,the HMPT process did not significantly affect the flotation performance of rare earths.The enrichment of fluorite in the tailings highlighted its further recovery potential.The integration of HMPT with magnetic separation and flotation presents an efficient strategy for recovering rare earths,iron,and fluorite from Bayan Obo ores.展开更多
The research on high-performance electromagnetic wave absorption materials with high-temperature and oxidative stability in extreme environments is gaining popularity.Herein,the lightweight silicon carbide nanowires(S...The research on high-performance electromagnetic wave absorption materials with high-temperature and oxidative stability in extreme environments is gaining popularity.Herein,the lightweight silicon carbide nanowires(SiC_(nws))/SiC composites are fabricated with in-situ SiC interface on one-dimensional oriented SiC_(nws)skeleton,which collaborative configuration by 3D printing and freeze casting assembly.The con-structed porous structure optimizes the impedance matching degree and scattering intensity,the maximum effective absorption bandwidth(EAB_(max))of 5.9 GHz and the minimum reflection loss(RL_(min))of−41.4 dB can be realized.Considering the inherent oxidation resistance of SiC,the composites present well-maintained absorption performance at 600℃.Even at 1100℃,the EAB_(max)of 4.9 GHz and RLmin of−30.4 dB also demonstrate the high-temperature absorption stability of the composites,indicating exceptional wave absorption properties and thermal stability.The slight attenuation can be attributed to the decrease in impedance matching capability accompanying the elevated dielectric constant.This work clarifies the impact of structure and component synergy on wave absorption behavior,and offers a novel approach to producing high-performance and high-temperature resistance ceramic-based electromagnetic wave absorption materials suitable for extreme environments.展开更多
Powder metallurgy was used to fabricate TiC-NiCr cermets and the oxidation behavior at 900℃ was investigated.Results reveal that TiC-NiCr cermets have uniform structures with excellent mechanical properties,whose har...Powder metallurgy was used to fabricate TiC-NiCr cermets and the oxidation behavior at 900℃ was investigated.Results reveal that TiC-NiCr cermets have uniform structures with excellent mechanical properties,whose hardness is 65 HRC and flexural strength is 1450 MPa.The high-temperature oxidation mechanism of TiC-based cermets was investigated through an X-ray diffractometer and scanning electron microscope.The added elements Ni and Cr along with their solid solutions not only bond with the hard phase TiC to ensure the physical performance of the cermet,but also impede the internal diffusion during oxidation by forming a dense composite oxide layer,thereby enhancing the oxidation resistance.The TiC-NiCr cermet exhibits a dense protective oxide layer at 900℃ and can endure continuous oxidation for approximately 1000 h.A methodology for fabricating TiC-NiCr metal matrix composites is proposed,and their oxidation resistance is evaluated,providing a theoretical and practical basis for simultaneously enhancing the mechanical properties and oxidation resistance and reducing production costs.展开更多
(TiZrHf)_(50)Ni_(30)Cu_(20-x)Co_(x)(x=2,4,6,at%)high-entropy high-temperature shape memory alloys were fabricated by watercooled copper crucible in a magnetic levitation vacuum melting furnace,and the effects of Co co...(TiZrHf)_(50)Ni_(30)Cu_(20-x)Co_(x)(x=2,4,6,at%)high-entropy high-temperature shape memory alloys were fabricated by watercooled copper crucible in a magnetic levitation vacuum melting furnace,and the effects of Co content on microstructure and mechanical properties were investigated.The results indicate that the grain size of the alloy decreases with increasing the Co content.In the as-cast state,the alloy consists primarily of the B19′phase,with a trace of B2 phase.The fracture morphology is predominantly composed of the B19′phase,whereas the B2 phase is nearly absent.Increasing the Co content or reducing the sample dimensions(d)markedly enhance the compressive strength and ductility of the alloy.When d=2 mm,the(TiZrHf)_(50)Ni_(30)Cu_(14)Co_(6) alloy demonstrates the optimal mechanical properties,achieving a compressive strength of 2142.39±1.8 MPa and a plasticity of 17.31±0.3%.The compressive cyclic test shows that with increasing the compressive strain,the residual strain of the(TiZrHf)_(50)Ni_(30)Cu_(14)Co_(6) alloy increases while the recovery ability declines.The superelastic recovery capability of the alloy is continuously enhanced.The superelastic recovery rate increases from 1.36%to 2.12%,the residual strain rate rises from 1.79%to 5.52%,the elastic recovery rate ascends from 3.86%to 7.36%,while the total recovery rate declines from 74.48%to 63.20%.展开更多
Co-based alloy coating was prepared on Zr alloy using laser melting and cladding technique to study the difference in the high-temperature oxidation behavior between pure metal Co coatings and Co-T800 alloy coatings,a...Co-based alloy coating was prepared on Zr alloy using laser melting and cladding technique to study the difference in the high-temperature oxidation behavior between pure metal Co coatings and Co-T800 alloy coatings,as well as the wear resistance of the coatings.Besides,the effect of changing the laser melting process on the coatings was also investigated.The oxidation mass gain at 800–1200℃and the high-temperature oxidation behavior during high-temperature treatment for 1 h of two coated Zr alloy samples were studied.Results show that the Co coating and the Co-T800 coating have better resistance against high-temperature oxidation.After oxidizing at 1000℃for 1 h,the thickness of the oxide layer of the uncoated sample was 241.0μm,whereas that of the sample with Co-based coating is only 11.8–35.5μm.The friction wear test shows that the depth of the abrasion mark of the coated sample is only 1/2 of that of the substrate,indicating that the hardness and wear resistance of the Zr substrate are greatly improved.The disadvantage of Co-based coatings is the inferior corrosion resistance in 3.5wt%NaCl solution.展开更多
The size and distribution patterns of bubbles within a laboratory-scale coarse-particle flotation column were examined using a high-speed camera-based dynamic measurement system.The effects of operational parameters s...The size and distribution patterns of bubbles within a laboratory-scale coarse-particle flotation column were examined using a high-speed camera-based dynamic measurement system.The effects of operational parameters such as superficial water velocity,air-flow rate,and frother dosage on bubble-size and distribution characteristics were investigated.This study aims to provide theoretical support for enabling fluidized-bed flotation within coarse-particle flotation columns.The results show that negative pressure for air inspiratory and bubble formation is generated by passing a high-speed jet through a throat,and the greatest number of bubbles are observed under natural inspiratory state at an air-liquid ratio of 1:3-1:2.5.Increasing the air-flow rate transforms the bubble diameter distribution from a peaked distribution to a more uniform distribution.Furthermore,the frother narrows the range of bubble-size distribution.A positive correlation exists between the bubble Sauter diameter and air-flow rate,with the bubble Sauter diameter bearing a negative correlation with the superficial water velocity and frother concentration.展开更多
Flotation behavior of stibiconite after sulfidation roasting with sulfur at a high temperature and the sulfidation mechanisms were investigated by ultraviolet spectrophotometry,X-ray diffraction(XRD)combining with the...Flotation behavior of stibiconite after sulfidation roasting with sulfur at a high temperature and the sulfidation mechanisms were investigated by ultraviolet spectrophotometry,X-ray diffraction(XRD)combining with thermodynamic calculation,X-ray photoelectron spectroscopy(XPS)and electron probe microanalysis(EPMA).The XRD and thermodynamic analyses revealed that the Sb_(3)O_(6)(OH)was reduced into Sb_(2)O_(4)and Sb_(2)O_(3),and was transformed into Sb_(2)S_(3)after introducing sulfur at high temperatures.Flotation test results show that flotation recovery of the stibiconite after sulfidation reaches 90.3%.Ultraviolet spectrophotometry tests confirm that adsorption capacity of sodium butyl xanthate(SBX)on surface of the roasted products has a positive relationship with S/Sb mole ratio.XPS analyses indicate that Sb-bearing species including mainly Sb_(2)S_(3),Sb_(2)O_(3)and Sb_(2)(SO_(4))_(3) are formed at the surface of particle after sulfidation.The EPMA analyses verify that the Sb_(2)S_(3)is generated at the outer layer of sample after sulfidation roasting,but the particle interior is mainly composed of antimony oxides.The sulfur atmosphere induces the outward migration of oxygen to form Sb_(2)O_(4).Then,the Sb_(2)O_(4)is transformed into Sb_(2)O_(3)in two pathways,and the Sb_(2)S_(3)is formed.These findings will provide theoretical support for recovering antimony from antimony oxide ores by xanthate flotation methods.展开更多
The tensile strength of rocks under real-time high-temperatures is essential for enhanced geothermal system development.However,the complex occurrence and deep burial of hot dry rocks limit the quantity and quality of...The tensile strength of rocks under real-time high-temperatures is essential for enhanced geothermal system development.However,the complex occurrence and deep burial of hot dry rocks limit the quantity and quality of standard samples for mechanical testing.This paper compared the tensile strengths obtained from Brazilian splitting tests on standard samples(with a diameter of 50 mm and a thickness of 25 mm)and micro-tensile samples(with a diameter of 50 mm and a thickness of 25 mm)of two types of granites.A power-law size effect model was established between the two sets of data,validating the reliability of the testing method.Then,miniature Brazilian splitting under real-time high-temperature,combined with X-ray diffraction(XRD)revealed temperature-dependent strength variations and microstructural damage mechanisms.The results show that:(1)The comparison error between the tensile strength obtained by the fitting model and that of the measured standard samples was less than 6%.(2)In real-time high-temperature conditions,tensile strength of granite exhibited non-monotonic behavior,increasing below 300°C before decreasing,with sharp declines at 400–500°C and 600–700°C.(3)Thermal damage stems from the differences in the high-temperature behavior of minerals,including dehydration,phase transformation,and differential expansion.展开更多
In recent years,the study of chalcopyrite and pyrite flotation surfaces using computational chemistry methods has made significant progress.However,current computational methods are limited by the small size of their ...In recent years,the study of chalcopyrite and pyrite flotation surfaces using computational chemistry methods has made significant progress.However,current computational methods are limited by the small size of their systems and insufficient consideration of hydration and temperature effects,making it difficult to fully replicate the real flotation environment of chalcopyrite and pyrite.In this study,we employed the self-consistent charge density functional tight-binding(SCC-DFTB)parameterization method to develop a parameter set,CuFeOrg,which includes the interactions between Cu-Fe-C-H-O-N-S-P-Zn elements,to investigate the surface interactions in large-scale flotation systems of chalcopyrite and pyrite.The results of bulk modulus,atomic displacement,band structure,surface relaxation,surface Mulliken charge distribution,and adsorption tests of typical flotation reagents on mineral surfaces demonstrate that CuFeOrg achieves DFT-level accuracy while significantly outperforming DFT in computational efficiency.By constructing large-scale hydration systems of mineral surfaces,as well as large-scale systems incorporating the combined interactions of mineral surfaces,flotation reagents,and hydration,we more realistically reproduce the actual flotation environment.Furthermore,the dynamic analysis results are consistent with mineral surface contact angle experiments.Additionally,CuFeOrg lays the foundation for future studies of more complex and diverse chalcopyrite and pyrite flotation surface systems.展开更多
The combined reagents of sodium N-oleoylsarcosinate(SNOS)with metal ions(Ca(Ⅱ),Mg(Ⅱ),Cu(Ⅱ),and Pb(Ⅱ))was employed to facilitate the separation of lepidolite from feldspar.The synergistic interaction mechanism of t...The combined reagents of sodium N-oleoylsarcosinate(SNOS)with metal ions(Ca(Ⅱ),Mg(Ⅱ),Cu(Ⅱ),and Pb(Ⅱ))was employed to facilitate the separation of lepidolite from feldspar.The synergistic interaction mechanism of this combined reagent was systematically investigated via contact angle measurements,AFM,FTIR,species distribution calculations,and DFT calculations.The results suggested that Ca(Ⅱ)exhibited the best selectivity for activating lepidolite flotation.SNOS was chemically adsorbed on the Ca(Ⅱ)-activated lepidolite surface with an adsorption energy of−1248.91 kJ/mol while a lower adsorption energy of−598.84 kJ/mol of SNOS on Ca(Ⅱ)-activated feldspar was calculated.Therefore,this combination of SNOS and Ca(Ⅱ)is a promising reagent scheme for the efficient recovery of lithium from aluminosilicate ore.展开更多
With the rapid advancement of science and technology,along with an increasing global focus on space exploration,there is a growing concern for addressing friction and wear issues in surface coatings for components ope...With the rapid advancement of science and technology,along with an increasing global focus on space exploration,there is a growing concern for addressing friction and wear issues in surface coatings for components operating in high-temperature environments within the aerospace sector.However,typical high-temperature coatings currently face challenges in effectively integrating excellent oxidation resistance,wear resistance,and lubrication properties in high-temperature settings.Studies have demonstrated the significant potential of Transition Metal Dichalcogenides(TMDCs)as lubricant additives in high-temperature lubrication,attributable to their distinctive crystal structures.Thus,this review concentrates on the compositional design of individual MX_(2)-type(M=W,Mo,Nb,Ta;X=S,Se)TMDCs(molybdenum disulfide(MoS_(2)),tungsten disulfide(WS2),niobium diselenide(NbSe_(2)),molybdenum diselenide(MoSe_(2)),tungsten diselenide(WSe_(2)))and their composites,including inorganic oxygen-containing sulfides,and explores the utilization of TMDCs in self-lubricating coatings.Furthermore,conventional preparation methods(mechanical exfoliation,liquid-phase ultrasonic exfoliation,chemical vapour deposition)for synthesizing TMDCs are outlined.Finally,an analysis of the lubrication mechanism of MX_(2)-type TMDCs is provided,along with future directions for enhancing the high-temperature lubrication performance of composite coatings.展开更多
The global reliance on phosphate rock for agriculture and other industries,coupled with chemical regulations in developed countries,has driven the search for green alternatives in apatite flotation.This review investi...The global reliance on phosphate rock for agriculture and other industries,coupled with chemical regulations in developed countries,has driven the search for green alternatives in apatite flotation.This review investigates eco-friendly collectors’effectiveness in promoting sustainable mineral processing,guiding future alternatives to traditional reagents.The manuscript discussed the surface properties of apatite and its interaction with eco-friendly collectors,assessing existing fundamental studies.This study sought to:(1)define,organize,and classify“eco-friendly”collectors;(2)evaluate their effect in IEP and contact angle;(3)provide a better understanding of the adsorption behavior of the different fatty acid chains into apatite surface;(4)assess their ability to reversely and directly float apatite;(5)address gaps to achieve selectivity and process optimization.Outcomes demonstrated that fatty acids are largely applied,but other renewable sources of these reagents have been promisingly evaluated.In addition,other natural reagents have been tested,and new green synthetics have demonstrated synergistic effects when combined with fatty acids,yielding significant improvements in grade and recovery.However,collector effectiveness varies with ore characteristics,like particle size and surface properties,which remain underexplored.Future research should design tailored collectors that align with mineralogical differences to enhance selectivity.展开更多
In froth flotation,overall recovery of the floatable particles consists of true recovery and recovery by entrainment,where entrainment refers to the non-selective recovery of particles in the concentrate.To understand...In froth flotation,overall recovery of the floatable particles consists of true recovery and recovery by entrainment,where entrainment refers to the non-selective recovery of particles in the concentrate.To understand and optimize the flotation process with regard to process conditions,it is essential to distinguish true flotation recovery from overall recovery.The established methods rely on tailored flotation experiments,unrealistic flotation conditions,or using external tracers which can be different in density and crystal structure to the mineral(s) of interest.This study presents an approach to utilize naturally occuring suitable tracers to estimate the entrainment component from overall recovery of individual particles by establishing a relationship between their settling velocity coefficient and recovery probability.Recovery probabilities of individual particles are computed using particle-based separation modelling.The approach is demonstrated for a copper ore,where naturally occurring rutile was used as the tracer to determine the entrained component of the overall recovery of chalcopyrite particles.Laboratory flotation experiments revealed that entrainment accounted for up to 6% of the overall recovery probability of fully liberated chalcopyrite particles in the fine size fractions.This approach provides a practical method for entrainment correction enabling a more accurate evaluation of true flotation recovery.展开更多
基金financially supported by the National Key Research and Development Plan of China(No.2022YFC2904603)the National Natural Science Foundation of China(No.52174268)。
文摘This study aimed to investigate the effect of varying pyrite(Py)content on copper(Cu)in the presence of different regrinding conditions,which were altered using different types of grinding media:iron,ceramic balls,and their mixture,followed by flotation in the cleaner stage.The flotation performance of rough Cu concentrate can be improved by changing the regrinding conditions based on the Py content.Scanning electron microscopy,X-ray spectrometry,ethylenediaminetetraacetic acid disodium salt extraction,and X-ray photoelectron spectroscopy studies illustrated that when the Py content was high,the use of iron media in regrinding promoted the generation of hydrophilic Fe OOH on the surface of Py and improved the Cu grade.The ceramic medium with a low Py content prevented excessive Fe OOH from covering the surface of chalcopyrite(Cpy).Electrochemical studies further showed that the galvanic corrosion current of Cpy-Py increased with the addition of Py and became stronger with the participation of iron media.
文摘This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standard system was established for comprehensive quality evaluation of HTD.There were obvious changes in the physicochemical properties,enzyme activities,and volatile flavor components at different storage periods,which affected the sensory evaluation of HTD to a certain extent.The results of high-throughput sequencing revealed significant microbial diversity,and showed that the bacterial community changed significantly more than did the fungal community.During the storage process,the dominant bacterial genera were Kroppenstedtia and Thermoascus.The correlation between dominant microorganisms and quality indicators highlighted their role in HTD quality.Lactococcus,Candida,Pichia,Paecilomyces,and protease activity played a crucial role in the formation of isovaleraldehyde.Acidic protease activity had the greatest impact on the microbial community.Moisture promoted isobutyric acid generation.Furthermore,the comprehensive quality evaluation standard system was established by the entropy weight method combined with multi-factor fuzzy mathematics.Consequently,this study provides innovative insights for comprehensive quality evaluation of HTD during storage and establishes a groundwork for scientific and rational storage of HTD and quality control of sauce-flavor Baijiu.
基金supported by Fundamental Research Projects of Yunnan Province,China(Nos.202101BE070001-009,202301AU070189).
文摘Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a collector.Flotation experiments showed that MFA produced a stronger inhibition effect on pyrite than on chalcopyrite.The separation of chalcopyrite from pyrite was realized by introducing 150 mg/L MFA at a pulp pH of approximately 8.0.The copper grade,copper recovery,and separation efficiency were 28.03%,84.79%,and 71.66%,respectively.Surface adsorption tests,zeta potential determinations,and localized electrochemical impedance spectroscopy tests showed that more MFA adsorbed on pyrite than on chalcopyrite,which weakened the subsequent interactions between pyrite and the collector.Atomic force microscope imaging further confirmed the adsorption of MFA on pyrite,and X-ray photoelectron spectroscopy results indicated that hydrophilic Fe-based species on the pyrite surfaces increased after exposure of pyrite to MFA,thereby decreasing the floatability of pyrite.
基金financial support from the Major Science and Technology Special Project of Yunnan Province,China(No.202302AB080012)the National Natural Science Foundation of China(No.52204274)the Shandong Provincial Natural Science Foundation,China(No.ZR2021QE122).
文摘To investigate the mechanisms of how nanobubbles enhance the flotation separation performance of galena from pyrite,the effects of nanobubbles on the surface properties of galena and pyrite and the interactions between mineral particles and air bubbles were examined in this study.Various analytical techniques,including focused beam reflectance measurement(FBRM),three-phase contact line(TPCL)analysis,atomic force microscopy(AFM),and contact angle measurement,were employed.It has been demonstrated that nanobubbles significantly enhanced the flotation recovery of galena and its flotation selectivity from pyrite,as compared to the conventional flotation process.The preferential formation of nanobubbles on the galena surface,which is more hydrophobic than pyrite surface,further increased the surface hydrophobicity and agglomeration of galena particles.The introduction of nanobubbles into the flotation system also increased in the maximum TPCL length and detachment length between the galena surface and bubbles,contributing to the enhanced flotation efficiency.
基金support from the National Natural Science Foundation of China(No.52204274)the Shandong Provincial Natural Science Foundation,China(No.ZR2021QE122)+1 种基金Shandong Provincial Department of Science and Technology Key Project,China(No.2023TZXD021)Shandong Provincial Department of Science and Technology,China(No.ZTYJY-KY-2033-11).
文摘Gold ores in the Jiaozhou region of China are characterized by their abundant reserves,low grade,fine dissemination,and chal-lenges in upgrading.Froth flotation,with xanthate as the collector,is a commonly employed method for enriching auriferous pyrite from these ores.This study aimed to develop a more efficient flotation process by utilizing cavitation nanobubbles for a low-grade gold ore.Batch flotation tests demonstrated that nanobubbles significantly enhanced the flotation performance of auriferous pyrite,as evidenced by improved concentrate S and Au grades and their recoveries.The mechanisms underlying this enhancement were explored by investigat-ing surface nanobubble(SNB)formation,bulk nanobubble(BNB)attachment to hydrophobic pyrite surfaces,and nanobubble-induced agglomeration using atomic force microscopy(AFM)and focused beam reflectance measurement(FBRM).The results revealed that nan-obubble coverage on the pyrite surface is a critical factor influencing surface hydrophobicity and agglomeration.SNBs exhibited higher coverage on pyrite surfaces with increased surface hydrophobicity,flow rate,and cavitation time.Similarly,BNB attachment on pyrite surfaces was significantly increased with surface hydrophobicity and cavitation time.Enhanced surface hydrophobicity,along with higher flow rates and cavitation times,promoted pyrite particle agglomeration owing to the increased nanobubble coverage,ultimately leading to improved flotation performance.
基金supported by Yunnan Science and Technology Leading Talent Project(No.202305AB350005)。
文摘Tin is a critical metal for various industries,making its recovery from low-grade cassiterite ores crucial.This study aimed to optimize the flotation recovery of cassiterite using multi-component collector systems.Several collectors were initially selected through micro-flotation tests,leading to the identification of optimal proportions for a four-component collector system(SHA-OHA-SPA-DBIA in a 4:3:2:1 ratio).Molecular dynamics simulations and surface tension tests were used to investigate the micellar behavior of these collectors in aqueous solution.The adsorption characteristics were quantified using microcalorimetry,enabling the determination of collection entropy and changes in Gibbs free energy.The four-component collector system showed the highest entropy change and the most favorable Gibbs free energy,leading to a cassiterite recovery of above 90%at a concentration of 8.0×10^(5)mol/L.Various analytical techniques were employed to systematically characterize the adsorption mechanism.The findings revealed a positive correlation between the adsorption products formed by the multicomponent collectors on the cassiterite surface and the entropy changes.Industrial-scale testing of the high-entropy collector system produced a tin concentrate with an Sn grade of 6.17%and an Sn recovery of 82.43%,demonstrating its substantial potential for practical applications in cassiterite flotation.
基金supported by the National Natural Science Foundation of China(Grant No.U21B2062)supported by the Key Laboratory for Carbonate Reservoirs of China National Petroleum Corporation。
文摘Burial dissolution is a critical diagenetic process influencing ultra-deep carbonate reservoir development and preservation.Artificial carbonate samples with different internal structures were prepared,and high-temperature and highpressure dissolution kinetic simulations were conducted.The results demonstrate that the intensity of burial dissolution is controlled by temperature and pressure,while tectonic-fluid activity influences the development pattern of burial dissolution,ultimately determining the direction of its differential modification.Extensive burial dissolution is likely to occur primarily at relatively shallow depths,significantly influencing reservoir formation,preservation,modification,and adjustment.The development of faults facilitates the maintenance of the intensity of burial dissolution.The maximum intensity of burial dissolution occurs at the tips and overlap zones of faults and intersections of multiple faults.The larger the scale of the faults,the more conducive it is to the development of burial dissolution.Burial dissolution fosters the formation of fault networks characterized by enhanced reservoir capacity and permeability.Burial dissolution controlled by episodic tectonic-fluid activity is a plausible explanation for forming the Tarim Basin's ultra-deep fault-controlled“stringbead-like”reservoirs.
基金the financial support received from the Key Program of National Natural Science Foundation of China(No.52130406)the National Key R&D Program of China(Nos.2021YFC2901000 and 2022YFC2905800)+1 种基金the General Program of National Natural Science Foundation of China(No.52274253)Natural Science Foundation Innovation Group Project of Hubei Province,China(No.2023AFA044)。
文摘Hydrogen-based mineral phase transformation(HMPT)technology has demonstrated its effectiveness in separating iron and enriching rare earths from Bayan Obo refractory ores.However,further research is needed to clarify the phase composition and floatability of rare earths obtained after HMPT owing to the associated phase transformations.This study explored the mineralogical characteristics and separation behavior of rare earths in HMPT-treated iron tailings.Process mineralogy studies conducted via BGRIMM process mineralogy analysis and X-ray diffraction revealed that the main valuable minerals in the tailings included rare-earth oxides(9.15wt%),monazite(5.31wt%),and fluorite(23.52wt%).The study also examined the impact of mineral liberation and gangue mineral intergrowth on flotation performance.Flotation tests achieved a rare-earth oxide(REO)grade of 74.12wt% with a recovery of 34.17% in open-circuit flotation,whereas closed-circuit flotation resulted in a REO grade of 60.27wt% with a recovery of 73%.Transmission electron microscopy and scanning electron microscopy coupled with energy-dispersive spectroscopy revealed that monazite remained stable during the HMPT process,while bastnaesite was transformed into Ce_(7)O_(12)and CeF_(3),leading to increased collector consumption.Nonetheless,the HMPT process did not significantly affect the flotation performance of rare earths.The enrichment of fluorite in the tailings highlighted its further recovery potential.The integration of HMPT with magnetic separation and flotation presents an efficient strategy for recovering rare earths,iron,and fluorite from Bayan Obo ores.
基金supported by the National Key R&D Program of China(No.2022YFB3707700)National Natural Science Foundation of China(No.52302121)+3 种基金Shanghai Sailing Program(No.23YF1454700)Shanghai Natural Science Foundation(No.23ZR1472700)Shanghai Post-doctoral Excellent Program(No.2022664)Shanghai Science and Technology Innovation Action Plan(No.21511104800).
文摘The research on high-performance electromagnetic wave absorption materials with high-temperature and oxidative stability in extreme environments is gaining popularity.Herein,the lightweight silicon carbide nanowires(SiC_(nws))/SiC composites are fabricated with in-situ SiC interface on one-dimensional oriented SiC_(nws)skeleton,which collaborative configuration by 3D printing and freeze casting assembly.The con-structed porous structure optimizes the impedance matching degree and scattering intensity,the maximum effective absorption bandwidth(EAB_(max))of 5.9 GHz and the minimum reflection loss(RL_(min))of−41.4 dB can be realized.Considering the inherent oxidation resistance of SiC,the composites present well-maintained absorption performance at 600℃.Even at 1100℃,the EAB_(max)of 4.9 GHz and RLmin of−30.4 dB also demonstrate the high-temperature absorption stability of the composites,indicating exceptional wave absorption properties and thermal stability.The slight attenuation can be attributed to the decrease in impedance matching capability accompanying the elevated dielectric constant.This work clarifies the impact of structure and component synergy on wave absorption behavior,and offers a novel approach to producing high-performance and high-temperature resistance ceramic-based electromagnetic wave absorption materials suitable for extreme environments.
基金National Natural Science Foundation of China(52376076)Open Fund of Material Corrosion and Protection Key Laboratory of Sichuan Province(2023CL13)Laiwu Vocational and Technical College Teachers Research Fund(2023jsky05)。
文摘Powder metallurgy was used to fabricate TiC-NiCr cermets and the oxidation behavior at 900℃ was investigated.Results reveal that TiC-NiCr cermets have uniform structures with excellent mechanical properties,whose hardness is 65 HRC and flexural strength is 1450 MPa.The high-temperature oxidation mechanism of TiC-based cermets was investigated through an X-ray diffractometer and scanning electron microscope.The added elements Ni and Cr along with their solid solutions not only bond with the hard phase TiC to ensure the physical performance of the cermet,but also impede the internal diffusion during oxidation by forming a dense composite oxide layer,thereby enhancing the oxidation resistance.The TiC-NiCr cermet exhibits a dense protective oxide layer at 900℃ and can endure continuous oxidation for approximately 1000 h.A methodology for fabricating TiC-NiCr metal matrix composites is proposed,and their oxidation resistance is evaluated,providing a theoretical and practical basis for simultaneously enhancing the mechanical properties and oxidation resistance and reducing production costs.
基金National Natural Science Foundation of China(12404230,52061027)Science and Technology Program Project of Gansu Province(22YF7GA155)+1 种基金Lanzhou Youth Science and Technology Talent Innovation Project(2023-QN-91)Zhejiang Provincial Natural Science Foundation of China(LY23E010002)。
文摘(TiZrHf)_(50)Ni_(30)Cu_(20-x)Co_(x)(x=2,4,6,at%)high-entropy high-temperature shape memory alloys were fabricated by watercooled copper crucible in a magnetic levitation vacuum melting furnace,and the effects of Co content on microstructure and mechanical properties were investigated.The results indicate that the grain size of the alloy decreases with increasing the Co content.In the as-cast state,the alloy consists primarily of the B19′phase,with a trace of B2 phase.The fracture morphology is predominantly composed of the B19′phase,whereas the B2 phase is nearly absent.Increasing the Co content or reducing the sample dimensions(d)markedly enhance the compressive strength and ductility of the alloy.When d=2 mm,the(TiZrHf)_(50)Ni_(30)Cu_(14)Co_(6) alloy demonstrates the optimal mechanical properties,achieving a compressive strength of 2142.39±1.8 MPa and a plasticity of 17.31±0.3%.The compressive cyclic test shows that with increasing the compressive strain,the residual strain of the(TiZrHf)_(50)Ni_(30)Cu_(14)Co_(6) alloy increases while the recovery ability declines.The superelastic recovery capability of the alloy is continuously enhanced.The superelastic recovery rate increases from 1.36%to 2.12%,the residual strain rate rises from 1.79%to 5.52%,the elastic recovery rate ascends from 3.86%to 7.36%,while the total recovery rate declines from 74.48%to 63.20%.
基金National Natural Science Foundation of China(52071126)Natural Science Foundation of Tianjin City,China(22JCQNJC01240)+2 种基金Central Guidance on Local Science and Technology Development Fund of Hebei Province(226Z1009G)Special Funds for Science and Technology Innovation in Hebei(2022X19)Anhui Provincial Natural Science Foundation(2308085ME135)。
文摘Co-based alloy coating was prepared on Zr alloy using laser melting and cladding technique to study the difference in the high-temperature oxidation behavior between pure metal Co coatings and Co-T800 alloy coatings,as well as the wear resistance of the coatings.Besides,the effect of changing the laser melting process on the coatings was also investigated.The oxidation mass gain at 800–1200℃and the high-temperature oxidation behavior during high-temperature treatment for 1 h of two coated Zr alloy samples were studied.Results show that the Co coating and the Co-T800 coating have better resistance against high-temperature oxidation.After oxidizing at 1000℃for 1 h,the thickness of the oxide layer of the uncoated sample was 241.0μm,whereas that of the sample with Co-based coating is only 11.8–35.5μm.The friction wear test shows that the depth of the abrasion mark of the coated sample is only 1/2 of that of the substrate,indicating that the hardness and wear resistance of the Zr substrate are greatly improved.The disadvantage of Co-based coatings is the inferior corrosion resistance in 3.5wt%NaCl solution.
基金supported by the National Key R&D Program of China(Nos.2023YFC3904202,2022YFC2904500)Major Science and Technology Program of Yunnan Province,China(No.202202AB080012).
文摘The size and distribution patterns of bubbles within a laboratory-scale coarse-particle flotation column were examined using a high-speed camera-based dynamic measurement system.The effects of operational parameters such as superficial water velocity,air-flow rate,and frother dosage on bubble-size and distribution characteristics were investigated.This study aims to provide theoretical support for enabling fluidized-bed flotation within coarse-particle flotation columns.The results show that negative pressure for air inspiratory and bubble formation is generated by passing a high-speed jet through a throat,and the greatest number of bubbles are observed under natural inspiratory state at an air-liquid ratio of 1:3-1:2.5.Increasing the air-flow rate transforms the bubble diameter distribution from a peaked distribution to a more uniform distribution.Furthermore,the frother narrows the range of bubble-size distribution.A positive correlation exists between the bubble Sauter diameter and air-flow rate,with the bubble Sauter diameter bearing a negative correlation with the superficial water velocity and frother concentration.
基金Projects(52074139,51964027)supported by the National Natural Science Foundation of ChinaProject(KKS 2202152011)supported by the High-level Talents of Yunnan Province,China。
文摘Flotation behavior of stibiconite after sulfidation roasting with sulfur at a high temperature and the sulfidation mechanisms were investigated by ultraviolet spectrophotometry,X-ray diffraction(XRD)combining with thermodynamic calculation,X-ray photoelectron spectroscopy(XPS)and electron probe microanalysis(EPMA).The XRD and thermodynamic analyses revealed that the Sb_(3)O_(6)(OH)was reduced into Sb_(2)O_(4)and Sb_(2)O_(3),and was transformed into Sb_(2)S_(3)after introducing sulfur at high temperatures.Flotation test results show that flotation recovery of the stibiconite after sulfidation reaches 90.3%.Ultraviolet spectrophotometry tests confirm that adsorption capacity of sodium butyl xanthate(SBX)on surface of the roasted products has a positive relationship with S/Sb mole ratio.XPS analyses indicate that Sb-bearing species including mainly Sb_(2)S_(3),Sb_(2)O_(3)and Sb_(2)(SO_(4))_(3) are formed at the surface of particle after sulfidation.The EPMA analyses verify that the Sb_(2)S_(3)is generated at the outer layer of sample after sulfidation roasting,but the particle interior is mainly composed of antimony oxides.The sulfur atmosphere induces the outward migration of oxygen to form Sb_(2)O_(4).Then,the Sb_(2)O_(4)is transformed into Sb_(2)O_(3)in two pathways,and the Sb_(2)S_(3)is formed.These findings will provide theoretical support for recovering antimony from antimony oxide ores by xanthate flotation methods.
基金supported by the National Natural Science Foundation of China(Nos.52174175 and 52274078)the Program for the Scientific and Technological Innovation Team in Universities of Henan Province(No.23IRTSTHN005)。
文摘The tensile strength of rocks under real-time high-temperatures is essential for enhanced geothermal system development.However,the complex occurrence and deep burial of hot dry rocks limit the quantity and quality of standard samples for mechanical testing.This paper compared the tensile strengths obtained from Brazilian splitting tests on standard samples(with a diameter of 50 mm and a thickness of 25 mm)and micro-tensile samples(with a diameter of 50 mm and a thickness of 25 mm)of two types of granites.A power-law size effect model was established between the two sets of data,validating the reliability of the testing method.Then,miniature Brazilian splitting under real-time high-temperature,combined with X-ray diffraction(XRD)revealed temperature-dependent strength variations and microstructural damage mechanisms.The results show that:(1)The comparison error between the tensile strength obtained by the fitting model and that of the measured standard samples was less than 6%.(2)In real-time high-temperature conditions,tensile strength of granite exhibited non-monotonic behavior,increasing below 300°C before decreasing,with sharp declines at 400–500°C and 600–700°C.(3)Thermal damage stems from the differences in the high-temperature behavior of minerals,including dehydration,phase transformation,and differential expansion.
基金supported by the National Natural Science Foundation of China(No.52374264)the National Key Technologies Research and Development Program of China(No.2024YFC2909600)the Major Science and Technology Projects in Yunnan Province(No.202402AB080010).
文摘In recent years,the study of chalcopyrite and pyrite flotation surfaces using computational chemistry methods has made significant progress.However,current computational methods are limited by the small size of their systems and insufficient consideration of hydration and temperature effects,making it difficult to fully replicate the real flotation environment of chalcopyrite and pyrite.In this study,we employed the self-consistent charge density functional tight-binding(SCC-DFTB)parameterization method to develop a parameter set,CuFeOrg,which includes the interactions between Cu-Fe-C-H-O-N-S-P-Zn elements,to investigate the surface interactions in large-scale flotation systems of chalcopyrite and pyrite.The results of bulk modulus,atomic displacement,band structure,surface relaxation,surface Mulliken charge distribution,and adsorption tests of typical flotation reagents on mineral surfaces demonstrate that CuFeOrg achieves DFT-level accuracy while significantly outperforming DFT in computational efficiency.By constructing large-scale hydration systems of mineral surfaces,as well as large-scale systems incorporating the combined interactions of mineral surfaces,flotation reagents,and hydration,we more realistically reproduce the actual flotation environment.Furthermore,the dynamic analysis results are consistent with mineral surface contact angle experiments.Additionally,CuFeOrg lays the foundation for future studies of more complex and diverse chalcopyrite and pyrite flotation surface systems.
基金financial support from the National Natural Science Foundation of China(Nos.U2067201,52204300)the National 111 Project,China(No.B14034)the Fundamental Research Funds for the Central Universities of Central South University,China(No.2021zzts0297).
文摘The combined reagents of sodium N-oleoylsarcosinate(SNOS)with metal ions(Ca(Ⅱ),Mg(Ⅱ),Cu(Ⅱ),and Pb(Ⅱ))was employed to facilitate the separation of lepidolite from feldspar.The synergistic interaction mechanism of this combined reagent was systematically investigated via contact angle measurements,AFM,FTIR,species distribution calculations,and DFT calculations.The results suggested that Ca(Ⅱ)exhibited the best selectivity for activating lepidolite flotation.SNOS was chemically adsorbed on the Ca(Ⅱ)-activated lepidolite surface with an adsorption energy of−1248.91 kJ/mol while a lower adsorption energy of−598.84 kJ/mol of SNOS on Ca(Ⅱ)-activated feldspar was calculated.Therefore,this combination of SNOS and Ca(Ⅱ)is a promising reagent scheme for the efficient recovery of lithium from aluminosilicate ore.
文摘With the rapid advancement of science and technology,along with an increasing global focus on space exploration,there is a growing concern for addressing friction and wear issues in surface coatings for components operating in high-temperature environments within the aerospace sector.However,typical high-temperature coatings currently face challenges in effectively integrating excellent oxidation resistance,wear resistance,and lubrication properties in high-temperature settings.Studies have demonstrated the significant potential of Transition Metal Dichalcogenides(TMDCs)as lubricant additives in high-temperature lubrication,attributable to their distinctive crystal structures.Thus,this review concentrates on the compositional design of individual MX_(2)-type(M=W,Mo,Nb,Ta;X=S,Se)TMDCs(molybdenum disulfide(MoS_(2)),tungsten disulfide(WS2),niobium diselenide(NbSe_(2)),molybdenum diselenide(MoSe_(2)),tungsten diselenide(WSe_(2)))and their composites,including inorganic oxygen-containing sulfides,and explores the utilization of TMDCs in self-lubricating coatings.Furthermore,conventional preparation methods(mechanical exfoliation,liquid-phase ultrasonic exfoliation,chemical vapour deposition)for synthesizing TMDCs are outlined.Finally,an analysis of the lubrication mechanism of MX_(2)-type TMDCs is provided,along with future directions for enhancing the high-temperature lubrication performance of composite coatings.
基金financially supported by CAMM(Center of Advanced Mining and Metallurgy/Green Flotation),as a center of excellence at the Luleå University of Technology.
文摘The global reliance on phosphate rock for agriculture and other industries,coupled with chemical regulations in developed countries,has driven the search for green alternatives in apatite flotation.This review investigates eco-friendly collectors’effectiveness in promoting sustainable mineral processing,guiding future alternatives to traditional reagents.The manuscript discussed the surface properties of apatite and its interaction with eco-friendly collectors,assessing existing fundamental studies.This study sought to:(1)define,organize,and classify“eco-friendly”collectors;(2)evaluate their effect in IEP and contact angle;(3)provide a better understanding of the adsorption behavior of the different fatty acid chains into apatite surface;(4)assess their ability to reversely and directly float apatite;(5)address gaps to achieve selectivity and process optimization.Outcomes demonstrated that fatty acids are largely applied,but other renewable sources of these reagents have been promisingly evaluated.In addition,other natural reagents have been tested,and new green synthetics have demonstrated synergistic effects when combined with fatty acids,yielding significant improvements in grade and recovery.However,collector effectiveness varies with ore characteristics,like particle size and surface properties,which remain underexplored.Future research should design tailored collectors that align with mineralogical differences to enhance selectivity.
基金funding from the European Union’s Horizon 2020 Marie Sklodowska-Curie Actions (MSCA), Innovative Training Networks (ITN), H2020-MSCA-ITN-2020 grant agreement(No.955805)。
文摘In froth flotation,overall recovery of the floatable particles consists of true recovery and recovery by entrainment,where entrainment refers to the non-selective recovery of particles in the concentrate.To understand and optimize the flotation process with regard to process conditions,it is essential to distinguish true flotation recovery from overall recovery.The established methods rely on tailored flotation experiments,unrealistic flotation conditions,or using external tracers which can be different in density and crystal structure to the mineral(s) of interest.This study presents an approach to utilize naturally occuring suitable tracers to estimate the entrainment component from overall recovery of individual particles by establishing a relationship between their settling velocity coefficient and recovery probability.Recovery probabilities of individual particles are computed using particle-based separation modelling.The approach is demonstrated for a copper ore,where naturally occurring rutile was used as the tracer to determine the entrained component of the overall recovery of chalcopyrite particles.Laboratory flotation experiments revealed that entrainment accounted for up to 6% of the overall recovery probability of fully liberated chalcopyrite particles in the fine size fractions.This approach provides a practical method for entrainment correction enabling a more accurate evaluation of true flotation recovery.
