The wetting behavior of slag–coke is a crucial factor influencing the permeability of the lower part of the blast furnace.However,a systematic understanding of the wetting behavior and underlying mechanisms between t...The wetting behavior of slag–coke is a crucial factor influencing the permeability of the lower part of the blast furnace.However,a systematic understanding of the wetting behavior and underlying mechanisms between titanium-containing slag and tuyere coke remains lacking.The sessile drop method was employed to explore the effects of temperature,binary basicity,FeO,and TiO_(2) contents on the wetting behavior of titanium-containing slag and tuyere coke.The results indicate that increasing the temperature enhances the adhesion and wettability of the droplet,reducing the contact angle.Meanwhile,it accelerates the chemical reactions between slag and coke,leading to faster equilibrium.Conversely,increasing slag basicity elevates the contact angle by inhibiting chemical reactions at the slag–coke interface.This inhibition reduces both contact area and depth,thereby hindering slag droplet spreading on the coke surface.The contact angle decreases as the FeO content in the slag increases.Notably,the increase in TiO_(2) content has a dual effect on slag–coke wettability.Initially,it promotes wetting by reducing surface tension and lowering the contact angle.While the TiO_(2) content exceeds 20 wt.%,Ti(C,N)forms a barrier layer at the slag–coke interface,hindering the contact between slag and coke and resulting in an increased contact angle.展开更多
Nanostructured TiO2 with different morphologies and crystal phases was successfully synthesized from titanium-containing electric furnace molten slag by using a hydrothermal method followed by reflux process in acid s...Nanostructured TiO2 with different morphologies and crystal phases was successfully synthesized from titanium-containing electric furnace molten slag by using a hydrothermal method followed by reflux process in acid solution. The effects of acid concentration, reflux time, and acid type on the formation of TiO2 were systematically investigated by scanning electron microscopy, X-ray dif- fraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and X-ray fluorescence (XRF). It is indicated that TiO2 nanorod with rutile phase is achieved in nitric or hydrochloric acid, while anatase TiO2 nanodisk is formed in sulfuric acid. With the increase of the concentration of hydrochloric acid from 0.3 to 1.5 mol-L-1, the dispersibility and crystallinity of the final product can be improved. With prolonging the reflux time from 6 to 14 h, the rutile TiO2 nanorod with uniform crystal size and high crystallinity is obtained. The growth mechanism of TiO2 nanorod and nanodisk prepared under different conditions was also discussed.展开更多
Titanium produces different compounds in gray iron. In order to determine their characteristics, a scanning electron microscope, an energy dispersive X-ray spectroscopy, and an optical microscopy were used to analyze ...Titanium produces different compounds in gray iron. In order to determine their characteristics, a scanning electron microscope, an energy dispersive X-ray spectroscopy, and an optical microscopy were used to analyze the morphology, distribution, and composition of titanium-containing compounds in metal- Iographic specimens and machined surfaces in four gray irons. The results show that the titanium-containing compounds in the gray irons are complex compounds containing V, Nb, Mn, S, and other metals, depending on the concentration of these elements in the iron. The number of titanium-containing compounds increases with increasing Ti content in the gray iron. Most of the titanium-containing compounds are located in the pearlite matrix, with some in the steadite and carbides. The results suggest that titanium-containing compounds reduce tool lifetime.展开更多
MIL-125 is a metal-organic framework with great potential for the adsorption and separation of xylene isomers.However,MIL-125 is usually synthesized under anhydrous and anaerobic conditions.In this study,homogeneously...MIL-125 is a metal-organic framework with great potential for the adsorption and separation of xylene isomers.However,MIL-125 is usually synthesized under anhydrous and anaerobic conditions.In this study,homogeneously shaped and highly crystalline MIL-125 was synthesized by introducing water-resistant titanium-containing oligomers into the synthesis process.With the assistance of the novel oligomers,MIL-125 can be synthesized in the presence of water,which meets batch-production requirements.The adsorption separation performance of the obtained highly crystalline MIL-125 was also significantly enhanced.The para-xylene/meta-xylene selectivity can reach 13.5 in mesitylene,which is higher than the selectivity values of most previously reported para-selective adsorbents.The MIL-125 xylene separation performance was verified using both batch adsorption and breakthrough experiments in the liquid phase.In addition,the influence of the solvent effect was evaluated through microcalorimetric experiments,liquid-phase adsorption experiments,and theoretical calculations.展开更多
To realize the resource utilization of the valuable metals in the titanium-containing blast furnace slag,the process route of “hydrochloric acid leaching-electrolysis-carbonization and carbon dioxide capture-preparat...To realize the resource utilization of the valuable metals in the titanium-containing blast furnace slag,the process route of “hydrochloric acid leaching-electrolysis-carbonization and carbon dioxide capture-preparation of calcium carbonate” was proposed.In this study,the influences of process conditions on the leaching rates of calcium,magnesium,aluminum,and iron and the phases of the leaching residue were investigated for the leaching process.The experimental results show that the HCl solution could selectively leach the elements from the titanium-containing blast furnace slag.The better leaching conditions are the HCl solution concentration of 4 mol/L,the leaching time of 30 min,the ratio of liquid volume to solid gas of 10 mL/g,and the stirring paddle speed of 300 r/min.Under the conditions,the leaching rates of calcium,magnesium,aluminum,and iron can reach 85.87%,73.41%,81.35%,and 59.08%,and the leaching rate of titanium is 10.71%.The iron and the aluminum are removed from the leachate to obtain iron-aluminum water purification agents,and the magnesium is removed from the leachate to obtain magnesium hydroxide.The leaching residue phase is dominated by perovskite,followed by magnesium silicate and tricalcium aluminate,and the titaniumrich material could be obtained from the leaching residue by desiliconization.展开更多
基金supported by the Postdoctor Project of Hubei Province(2024HBBHCXA074)National Natural Science Foundation of China(51974212)+2 种基金China Baowu Low Carbon Metallurgy Innovation Foundation(BWLCF202116)Foundation of Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking(NPISlab25-03)Science and Technology Major Project of Wuhan(2023020302020572).
文摘The wetting behavior of slag–coke is a crucial factor influencing the permeability of the lower part of the blast furnace.However,a systematic understanding of the wetting behavior and underlying mechanisms between titanium-containing slag and tuyere coke remains lacking.The sessile drop method was employed to explore the effects of temperature,binary basicity,FeO,and TiO_(2) contents on the wetting behavior of titanium-containing slag and tuyere coke.The results indicate that increasing the temperature enhances the adhesion and wettability of the droplet,reducing the contact angle.Meanwhile,it accelerates the chemical reactions between slag and coke,leading to faster equilibrium.Conversely,increasing slag basicity elevates the contact angle by inhibiting chemical reactions at the slag–coke interface.This inhibition reduces both contact area and depth,thereby hindering slag droplet spreading on the coke surface.The contact angle decreases as the FeO content in the slag increases.Notably,the increase in TiO_(2) content has a dual effect on slag–coke wettability.Initially,it promotes wetting by reducing surface tension and lowering the contact angle.While the TiO_(2) content exceeds 20 wt.%,Ti(C,N)forms a barrier layer at the slag–coke interface,hindering the contact between slag and coke and resulting in an increased contact angle.
基金financially supported by the National Natural Science Foundation of China(Nos.51272025 and 51072022)the State Basic Research Development Program of China(973 Program)(No.2007CB613608)the New Century Excellent Researcher Award Program from Ministry of Education of China(No.NCET-08-0732)
文摘Nanostructured TiO2 with different morphologies and crystal phases was successfully synthesized from titanium-containing electric furnace molten slag by using a hydrothermal method followed by reflux process in acid solution. The effects of acid concentration, reflux time, and acid type on the formation of TiO2 were systematically investigated by scanning electron microscopy, X-ray dif- fraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and X-ray fluorescence (XRF). It is indicated that TiO2 nanorod with rutile phase is achieved in nitric or hydrochloric acid, while anatase TiO2 nanodisk is formed in sulfuric acid. With the increase of the concentration of hydrochloric acid from 0.3 to 1.5 mol-L-1, the dispersibility and crystallinity of the final product can be improved. With prolonging the reflux time from 6 to 14 h, the rutile TiO2 nanorod with uniform crystal size and high crystallinity is obtained. The growth mechanism of TiO2 nanorod and nanodisk prepared under different conditions was also discussed.
文摘Titanium produces different compounds in gray iron. In order to determine their characteristics, a scanning electron microscope, an energy dispersive X-ray spectroscopy, and an optical microscopy were used to analyze the morphology, distribution, and composition of titanium-containing compounds in metal- Iographic specimens and machined surfaces in four gray irons. The results show that the titanium-containing compounds in the gray irons are complex compounds containing V, Nb, Mn, S, and other metals, depending on the concentration of these elements in the iron. The number of titanium-containing compounds increases with increasing Ti content in the gray iron. Most of the titanium-containing compounds are located in the pearlite matrix, with some in the steadite and carbides. The results suggest that titanium-containing compounds reduce tool lifetime.
文摘MIL-125 is a metal-organic framework with great potential for the adsorption and separation of xylene isomers.However,MIL-125 is usually synthesized under anhydrous and anaerobic conditions.In this study,homogeneously shaped and highly crystalline MIL-125 was synthesized by introducing water-resistant titanium-containing oligomers into the synthesis process.With the assistance of the novel oligomers,MIL-125 can be synthesized in the presence of water,which meets batch-production requirements.The adsorption separation performance of the obtained highly crystalline MIL-125 was also significantly enhanced.The para-xylene/meta-xylene selectivity can reach 13.5 in mesitylene,which is higher than the selectivity values of most previously reported para-selective adsorbents.The MIL-125 xylene separation performance was verified using both batch adsorption and breakthrough experiments in the liquid phase.In addition,the influence of the solvent effect was evaluated through microcalorimetric experiments,liquid-phase adsorption experiments,and theoretical calculations.
基金Funded by the National Natural Science Foundation of China Youth Fund(No.52204419)the Liaoning Provincial Natural Science Foundation(No.2022-BS-076)the Guangxi Science and Technology Major Project(No.2021AA12013)。
文摘To realize the resource utilization of the valuable metals in the titanium-containing blast furnace slag,the process route of “hydrochloric acid leaching-electrolysis-carbonization and carbon dioxide capture-preparation of calcium carbonate” was proposed.In this study,the influences of process conditions on the leaching rates of calcium,magnesium,aluminum,and iron and the phases of the leaching residue were investigated for the leaching process.The experimental results show that the HCl solution could selectively leach the elements from the titanium-containing blast furnace slag.The better leaching conditions are the HCl solution concentration of 4 mol/L,the leaching time of 30 min,the ratio of liquid volume to solid gas of 10 mL/g,and the stirring paddle speed of 300 r/min.Under the conditions,the leaching rates of calcium,magnesium,aluminum,and iron can reach 85.87%,73.41%,81.35%,and 59.08%,and the leaching rate of titanium is 10.71%.The iron and the aluminum are removed from the leachate to obtain iron-aluminum water purification agents,and the magnesium is removed from the leachate to obtain magnesium hydroxide.The leaching residue phase is dominated by perovskite,followed by magnesium silicate and tricalcium aluminate,and the titaniumrich material could be obtained from the leaching residue by desiliconization.