This study used specularite, a high-gradient magnetic separation concentrate, as a raw material in reverse flotation.An iron concentrate with a grade of 65.1 wt% and a recovery rate of 75.31% were obtained.A centrifug...This study used specularite, a high-gradient magnetic separation concentrate, as a raw material in reverse flotation.An iron concentrate with a grade of 65.1 wt% and a recovery rate of 75.31% were obtained.A centrifugal concentrator served as the deep purification equipment for the preparation of iron oxide red pigments, and its optimal rotating drum speed, feed concentration, and other conditions were determined.Under optimal conditions, a high-purity iron oxide concentrate with a grade of 69.38 wt% and a recovery rate of 80.89% were obtained and used as a raw material for preparing iron oxide red pigment.Calcining with sulfuric acid produced iron red pigments with different hues.Simultaneously, middlings with a grade of 60.20 wt% and a recovery rate of 17.51% were obtained and could be used in blast furnace ironmaking.High-value utilization of specularite beneficiation products was thus achieved.展开更多
To investigate the physical and chemical properties of the steelmaking dust, wet sieve separation, XRD, SEM, EDS, and traditional chemical analysis were carded out to obtain the particle size distribution, mineralogy,...To investigate the physical and chemical properties of the steelmaking dust, wet sieve separation, XRD, SEM, EDS, and traditional chemical analysis were carded out to obtain the particle size distribution, mineralogy, morphology, and the chemical composition of the dust. The dust with a total Fe content of 64.08wt% has coarse metallic iron, magnetite and hematite grains, while free clay minerals with a size of 〈38 μm are mainly iosidefite, calcium silicate, and calcite, which are conglomerated to each other. By following the procedures of wet magnetic separation, acid leaching, and oxidization calcination, magnetic materials were recycled and further prepared as iron oxide red with a productivity of 0.54 ton per unit ton of the dust. Middle iron concentrate with an Fe content of 65.92wt% can be reused as feeding material in the ironmaking industry. Additionally, washed water from acid leaching with an Fe^3+ ion content of less than 5 g·L^-1 was recovered as feeding water in the wet magnetic separation procedure. 2008 University of Science and Technology Beijing. All fights reserved.展开更多
The interactions of two types of cells (red blood cells, Caco-2 cells) with magnetic iron oxide nanoparticles (non-grafted, citrate-grafted, dendrimer-grafted) of 11 nm in size have been investigated. We focused on tw...The interactions of two types of cells (red blood cells, Caco-2 cells) with magnetic iron oxide nanoparticles (non-grafted, citrate-grafted, dendrimer-grafted) of 11 nm in size have been investigated. We focused on two important physiological parameters of the cells, the intracellular pH and the intracellular Ca2+ content. The results show that the nanoparticles do not have a significant influence on the pH and Ca2+ content of Caco-2 cells. The Ca2+ content of red blood cells is also not affected but the intracellular pH is slightly reduced.展开更多
The absorbent composing of Bayer red mud and water was prepared and applied to removing SO2 from flue gas.Effects of the ratio of liquid to solid(L/S),the absorption temperature,the inlet SO2 concentration,the O2 conc...The absorbent composing of Bayer red mud and water was prepared and applied to removing SO2 from flue gas.Effects of the ratio of liquid to solid(L/S),the absorption temperature,the inlet SO2 concentration,the O2 concentration,SO4^2-and other different components of Bayer red mud on desulfurization were conducted.The mechanism of flue gas desulfurization was also established.The results indicated that L/S was the prominent factor,followed by the inlet SO2 concentration and the temperature was the least among them.The optimum condition was as follows:L/S,the temperature and the SO2 concentration were 20:1,25℃and 1000 mg/m^3,respectively,under the gas flow of 1.5 L/min.The desulfurization efficiency was not significantly influenced when O2 concentration was above 7%.The accumulation of SO4^2-inhibited the desulfurization efficiency.The alkali absorption and metal ions liquid catalytic oxidation were involved in the process,which accounted for 98.61%.展开更多
Surface-modification of fine red iron oxide pigment was carried out in an aqueous solution of sodium poly-acrylate. The sedimentation time of modified samples in water increased from 1.05 to 264.4 hours while the part...Surface-modification of fine red iron oxide pigment was carried out in an aqueous solution of sodium poly-acrylate. The sedimentation time of modified samples in water increased from 1.05 to 264.4 hours while the particle size (d50 ) decreased from 1.09 to 0.85 mm, and the tinting strength increased from 100 to 115. The surface-modification as well as the dispersing and stabilizing mechanisms in aqueous solution of the samples were studied by means of IR, Thermal analysis and Zeta potential. The results showed that the modifier molecules acted on the surface of the particles by chemical and physical adsorption, and after the particles were dispersed in aqueous solution, endowing the particle surface with a relatively high negative Zeta potential, thus enhancing electrostatic and steric repulsion between particles for their effective stabilization.展开更多
基金jointly funded by the National Natural Science Foundation of China (No.51304181)the Key Research Program of Frontier Sciences of Chinese Academy of Sciences (No.QYZDJ-SSW-JSC021)the Key Research Program of Chinese Academy of Sciences (No.ZDRW-ZS-2018-1)。
文摘This study used specularite, a high-gradient magnetic separation concentrate, as a raw material in reverse flotation.An iron concentrate with a grade of 65.1 wt% and a recovery rate of 75.31% were obtained.A centrifugal concentrator served as the deep purification equipment for the preparation of iron oxide red pigments, and its optimal rotating drum speed, feed concentration, and other conditions were determined.Under optimal conditions, a high-purity iron oxide concentrate with a grade of 69.38 wt% and a recovery rate of 80.89% were obtained and used as a raw material for preparing iron oxide red pigment.Calcining with sulfuric acid produced iron red pigments with different hues.Simultaneously, middlings with a grade of 60.20 wt% and a recovery rate of 17.51% were obtained and could be used in blast furnace ironmaking.High-value utilization of specularite beneficiation products was thus achieved.
文摘To investigate the physical and chemical properties of the steelmaking dust, wet sieve separation, XRD, SEM, EDS, and traditional chemical analysis were carded out to obtain the particle size distribution, mineralogy, morphology, and the chemical composition of the dust. The dust with a total Fe content of 64.08wt% has coarse metallic iron, magnetite and hematite grains, while free clay minerals with a size of 〈38 μm are mainly iosidefite, calcium silicate, and calcite, which are conglomerated to each other. By following the procedures of wet magnetic separation, acid leaching, and oxidization calcination, magnetic materials were recycled and further prepared as iron oxide red with a productivity of 0.54 ton per unit ton of the dust. Middle iron concentrate with an Fe content of 65.92wt% can be reused as feeding material in the ironmaking industry. Additionally, washed water from acid leaching with an Fe^3+ ion content of less than 5 g·L^-1 was recovered as feeding water in the wet magnetic separation procedure. 2008 University of Science and Technology Beijing. All fights reserved.
文摘The interactions of two types of cells (red blood cells, Caco-2 cells) with magnetic iron oxide nanoparticles (non-grafted, citrate-grafted, dendrimer-grafted) of 11 nm in size have been investigated. We focused on two important physiological parameters of the cells, the intracellular pH and the intracellular Ca2+ content. The results show that the nanoparticles do not have a significant influence on the pH and Ca2+ content of Caco-2 cells. The Ca2+ content of red blood cells is also not affected but the intracellular pH is slightly reduced.
基金Project(2017YFC0210500)supported by the National Key Technology R&D Program of ChinaProject(2017ACA092)supported by the Major Projects of Technical Innovation in Hubei Province,China
文摘The absorbent composing of Bayer red mud and water was prepared and applied to removing SO2 from flue gas.Effects of the ratio of liquid to solid(L/S),the absorption temperature,the inlet SO2 concentration,the O2 concentration,SO4^2-and other different components of Bayer red mud on desulfurization were conducted.The mechanism of flue gas desulfurization was also established.The results indicated that L/S was the prominent factor,followed by the inlet SO2 concentration and the temperature was the least among them.The optimum condition was as follows:L/S,the temperature and the SO2 concentration were 20:1,25℃and 1000 mg/m^3,respectively,under the gas flow of 1.5 L/min.The desulfurization efficiency was not significantly influenced when O2 concentration was above 7%.The accumulation of SO4^2-inhibited the desulfurization efficiency.The alkali absorption and metal ions liquid catalytic oxidation were involved in the process,which accounted for 98.61%.
文摘Surface-modification of fine red iron oxide pigment was carried out in an aqueous solution of sodium poly-acrylate. The sedimentation time of modified samples in water increased from 1.05 to 264.4 hours while the particle size (d50 ) decreased from 1.09 to 0.85 mm, and the tinting strength increased from 100 to 115. The surface-modification as well as the dispersing and stabilizing mechanisms in aqueous solution of the samples were studied by means of IR, Thermal analysis and Zeta potential. The results showed that the modifier molecules acted on the surface of the particles by chemical and physical adsorption, and after the particles were dispersed in aqueous solution, endowing the particle surface with a relatively high negative Zeta potential, thus enhancing electrostatic and steric repulsion between particles for their effective stabilization.