In order to discuss the particle-bubble interaction during the electro-flotation of cassiterite,the recovery of cassiterite with different particle sizes was investigated,and the collision mechanism between the cassit...In order to discuss the particle-bubble interaction during the electro-flotation of cassiterite,the recovery of cassiterite with different particle sizes was investigated,and the collision mechanism between the cassiterite particles and H2 bubbles was explored.The flotation tests were carried out in a single bubble flotation cell.The results show that cassiterite particles 10 μm,10-20 μm,20?38 μm and 38-74 μm match with bubbles with size of 50-150 μm,about 250 μm,74 μm and 74 μm,respectively,and a better recovery can be obtained.It is demonstrated that the recovery of cassiterite is influenced by the size of cassiterite particles and bubbles.Furthermore,the probabilities of collision,adhesion,detachment and collection were calculated using the collision,attachment and collection models.Theoretical calculation results show that the collision probability decreases sharply with decreasing particle size and increasing bubble size(below 150 μm).The attachment probability would increase from the effective collision,leading to the increase of recovery.展开更多
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 composition of passive layer of chalcopyrite was investigated by X-ray photoelectron spectroscopy(XPS), accompanied with cyclic voltammetry(CV). The leaching experiment shows that the extraction rates of Cu wi...The composition of passive layer of chalcopyrite was investigated by X-ray photoelectron spectroscopy(XPS), accompanied with cyclic voltammetry(CV). The leaching experiment shows that the extraction rates of Cu with leaching for 30 d by sterile control and microorganisms are 4.0% and 21.5%, respectively. In comparison, 3.8% and 10.5% Fe are leached by sterile control and microorganisms, respectively. The results of XPS studies suggest that Fe atoms dissolve preferentially from the chalcopyrite lattice, and disulfide(S22-), polysulfide(Sn2-) and elemental sulfur(S0) are identified on the chalcopyrite surfaces leached by sterile control and microorganisms. Additionally, sulfate(SO42-) is detected on the chalcopyrite surfaces leached by microorganisms, and most of it probably originates from jarosite. The analysis of CV results reveals that metal-deficient sulfide(Cu1-xFe1-yS2-z, yx) and elemental sulfur(S0) passivate the surface of chalcopyrite electrode. The elemental sulfur and/or jarosite coating on the chalcopyrite surface may have impact on the leaching process; however, the disulfide, polysulfide or metal-deficient sulfide plays a more key role in the chalcopyrite leaching.展开更多
基金Project(2010CB630905)supported by the National Basic Research and Development Program of ChinaProject(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
基金Project(50774094)supported by the National Natural Science Foundation of ChinaProject(2010CB630905)supported by the National Basic Research Program of China
文摘In order to discuss the particle-bubble interaction during the electro-flotation of cassiterite,the recovery of cassiterite with different particle sizes was investigated,and the collision mechanism between the cassiterite particles and H2 bubbles was explored.The flotation tests were carried out in a single bubble flotation cell.The results show that cassiterite particles 10 μm,10-20 μm,20?38 μm and 38-74 μm match with bubbles with size of 50-150 μm,about 250 μm,74 μm and 74 μm,respectively,and a better recovery can be obtained.It is demonstrated that the recovery of cassiterite is influenced by the size of cassiterite particles and bubbles.Furthermore,the probabilities of collision,adhesion,detachment and collection were calculated using the collision,attachment and collection models.Theoretical calculation results show that the collision probability decreases sharply with decreasing particle size and increasing bubble size(below 150 μm).The attachment probability would increase from the effective collision,leading to the increase of recovery.
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(2018TP1002) supported by Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources,ChinaProject supported by Co-Innovation Centre for Clean and Efficient Utilization of Strategic Metal Mineral Resources,China。
基金Project(51274255)supported by the National Natural Science Foundation of ChinaProject(20130162110007)supported by the Doctoral Fund of Ministry of Education of China+1 种基金Project supported by the Co-Innovation Center for Clean and Efficient Utilization of Strategic Metal Mineral ResourcesChina
文摘The composition of passive layer of chalcopyrite was investigated by X-ray photoelectron spectroscopy(XPS), accompanied with cyclic voltammetry(CV). The leaching experiment shows that the extraction rates of Cu with leaching for 30 d by sterile control and microorganisms are 4.0% and 21.5%, respectively. In comparison, 3.8% and 10.5% Fe are leached by sterile control and microorganisms, respectively. The results of XPS studies suggest that Fe atoms dissolve preferentially from the chalcopyrite lattice, and disulfide(S22-), polysulfide(Sn2-) and elemental sulfur(S0) are identified on the chalcopyrite surfaces leached by sterile control and microorganisms. Additionally, sulfate(SO42-) is detected on the chalcopyrite surfaces leached by microorganisms, and most of it probably originates from jarosite. The analysis of CV results reveals that metal-deficient sulfide(Cu1-xFe1-yS2-z, yx) and elemental sulfur(S0) passivate the surface of chalcopyrite electrode. The elemental sulfur and/or jarosite coating on the chalcopyrite surface may have impact on the leaching process; however, the disulfide, polysulfide or metal-deficient sulfide plays a more key role in the chalcopyrite leaching.