The hydrophobic flocculation of marmatite fines in aqueous suspensions induced by butyl xanthate （KBX） and ammonium dibutyl dithiophosphate （ADD） was investigated using laser particle size analysis, microscopy ana...The hydrophobic flocculation of marmatite fines in aqueous suspensions induced by butyl xanthate （KBX） and ammonium dibutyl dithiophosphate （ADD） was investigated using laser particle size analysis, microscopy analysis, electrophoretic light scattering, contact angle measurement and infrared spectroscopy. The studies were performed on single minerals with size 〈20 μm by varying several parameters, including pH, collector concentration and kerosene addition. The results show that the floc fotation closely correlated with the size of flocs and the particle hydrophobicity, but was not lowered with increasing the particle surface charges due to collector adsorption. Under good operating conditions, the floc flotation of marmatite fines as a function of KBX and ADD can all reach floatability over 90%, in comparison with conventional flotation obtaining floatability of about 60%. It also has been found that a small addition of kerosene greatly improved the floc flotation because of the formation of oil films on marmatite particles. The results of FTIR spectra indicate that adsorption of the two collectors onto marmatite were chemical adsorption.展开更多
The influence of pulp temperature on the floatability and adsorption behavior of fine wolframite with sodium oleate was investigated by microflotation experiments, electric conductivity tests, adsorption measurements,...The influence of pulp temperature on the floatability and adsorption behavior of fine wolframite with sodium oleate was investigated by microflotation experiments, electric conductivity tests, adsorption measurements, and FT-IR analysis. Microflotation results show that fine wolframite with sodium oleate exhibits a good floatability at pH 8–9. Electric conductivity tests indicate that the high temperature enhances the ionization degree and electric mobility of oleate species, then the flotation recovery of fine wolframite and the adsorption amount of sodium oleate are observed to increase with the rise in pulp temperature. The results of adsorption experiments are found to meet Freundlich isotherms successfully, and the isosteric enthalpy （ΔH^Θ） is in conformity with the chemical bonding. The changes in FT-IR analysis provide sufficient evidence that sodium oleate interacts with the metal cations of wolframite surface, and the increase in pulp temperature clearly promotes the chemisorption intensity. These findings will be beneficial to strengthen the flotation behavior of fine wolframite.展开更多
Pyrolysis has the potential of transforming waste into valuable products. Pyrolytic carbon black (PCB) is one of the most important products resulting from the pyrolysis of used tires. One of the most significant appl...Pyrolysis has the potential of transforming waste into valuable products. Pyrolytic carbon black (PCB) is one of the most important products resulting from the pyrolysis of used tires. One of the most significant applica-tions of modified pyrolytic carbon black is its use as pigment for offset printing ink to obtain high added values. Inverse gas chromatography (IGC) results show that a large quantity of inorganic matters and carbonaceous deposit are removed by treating the pyrolytic carbon black with nitric acid solution. Plenty of active sites originally occu-pied by inorganic ash and coke are recovered. The surface energy of pyrolytic carbon black (TWPC)modified by titanate-coupling agent-especially the specific interaction γ sspdetermined by the specific probe molecule, tolu-ene-shows the strong interaction between the TWPC and the synthetic resins. The offset printing ink performance confirms the IGC prediction. And TWPC has the great potential of applications in printing ink industry as pigment.展开更多
The mechanical properties, thermal and gasohol resistance of the natural zeolite, rice husk ash （RHA） and perlite-filled natural rubber （NR） with addition of carbon black （CB） loading was studied. The amount of ...The mechanical properties, thermal and gasohol resistance of the natural zeolite, rice husk ash （RHA） and perlite-filled natural rubber （NR） with addition of carbon black （CB） loading was studied. The amount of fillers （natural zeolite, RHA and perlite） filled in the vulcanizates has been fixed at 20 phr, while CB loading was varied in a range of 0-45 phr. It was found that the tensile strength, percentage of elongation at break, modulus and hardness of the vulcanizates filled with all kinds of fillers increased with the increase of CB loading, while there was no significant change in the compression set. Moreover, at this particular filler loading （20 phr）, the addition of perlite has significant effect on gasohol resistance of the vulcanizates in which gasohol resistance （various ethanol ratio） of the vulcanizates was significantly improved with perlite loading compared with others.展开更多
基金Project(51274255)supported by the National Natural Science Foundation of ChinaProject supported by the Foundation of State Key Laboratory of Comprehensive Utilization of Low-Grade Ores(Zijin Mining Group Co.,Ltd),China
文摘The hydrophobic flocculation of marmatite fines in aqueous suspensions induced by butyl xanthate （KBX） and ammonium dibutyl dithiophosphate （ADD） was investigated using laser particle size analysis, microscopy analysis, electrophoretic light scattering, contact angle measurement and infrared spectroscopy. The studies were performed on single minerals with size 〈20 μm by varying several parameters, including pH, collector concentration and kerosene addition. The results show that the floc fotation closely correlated with the size of flocs and the particle hydrophobicity, but was not lowered with increasing the particle surface charges due to collector adsorption. Under good operating conditions, the floc flotation of marmatite fines as a function of KBX and ADD can all reach floatability over 90%, in comparison with conventional flotation obtaining floatability of about 60%. It also has been found that a small addition of kerosene greatly improved the floc flotation because of the formation of oil films on marmatite particles. The results of FTIR spectra indicate that adsorption of the two collectors onto marmatite were chemical adsorption.
基金Project(51704058)supported by the National Natural Science Foundation of China
文摘The influence of pulp temperature on the floatability and adsorption behavior of fine wolframite with sodium oleate was investigated by microflotation experiments, electric conductivity tests, adsorption measurements, and FT-IR analysis. Microflotation results show that fine wolframite with sodium oleate exhibits a good floatability at pH 8–9. Electric conductivity tests indicate that the high temperature enhances the ionization degree and electric mobility of oleate species, then the flotation recovery of fine wolframite and the adsorption amount of sodium oleate are observed to increase with the rise in pulp temperature. The results of adsorption experiments are found to meet Freundlich isotherms successfully, and the isosteric enthalpy （ΔH^Θ） is in conformity with the chemical bonding. The changes in FT-IR analysis provide sufficient evidence that sodium oleate interacts with the metal cations of wolframite surface, and the increase in pulp temperature clearly promotes the chemisorption intensity. These findings will be beneficial to strengthen the flotation behavior of fine wolframite.
基金Supported by the National Natural Science Foundation of China (No.20176051) and the Key Natural Science Foundation ofChina (No.20490205).
文摘Pyrolysis has the potential of transforming waste into valuable products. Pyrolytic carbon black (PCB) is one of the most important products resulting from the pyrolysis of used tires. One of the most significant applica-tions of modified pyrolytic carbon black is its use as pigment for offset printing ink to obtain high added values. Inverse gas chromatography (IGC) results show that a large quantity of inorganic matters and carbonaceous deposit are removed by treating the pyrolytic carbon black with nitric acid solution. Plenty of active sites originally occu-pied by inorganic ash and coke are recovered. The surface energy of pyrolytic carbon black (TWPC)modified by titanate-coupling agent-especially the specific interaction γ sspdetermined by the specific probe molecule, tolu-ene-shows the strong interaction between the TWPC and the synthetic resins. The offset printing ink performance confirms the IGC prediction. And TWPC has the great potential of applications in printing ink industry as pigment.
文摘The mechanical properties, thermal and gasohol resistance of the natural zeolite, rice husk ash （RHA） and perlite-filled natural rubber （NR） with addition of carbon black （CB） loading was studied. The amount of fillers （natural zeolite, RHA and perlite） filled in the vulcanizates has been fixed at 20 phr, while CB loading was varied in a range of 0-45 phr. It was found that the tensile strength, percentage of elongation at break, modulus and hardness of the vulcanizates filled with all kinds of fillers increased with the increase of CB loading, while there was no significant change in the compression set. Moreover, at this particular filler loading （20 phr）, the addition of perlite has significant effect on gasohol resistance of the vulcanizates in which gasohol resistance （various ethanol ratio） of the vulcanizates was significantly improved with perlite loading compared with others.
