In the light of the knowledge gained by the study of electrochemical flotation for galena and selective flotation of galena from lead zinc iron sulfide ores, a technology for accurate potential control based on intrin...In the light of the knowledge gained by the study of electrochemical flotation for galena and selective flotation of galena from lead zinc iron sulfide ores, a technology for accurate potential control based on intrinsic electrochemical behavior in grinding flotation systems has been developed and is called "Original Potential Flotation (OPF)". The optimum conditions for the original potential flotation of galena from Pb Zn Fe sulfide ores are as follows: pH values of 12.5 12.8, potential of 150 180 mV and with diethyldithioncarbamate (DDTC) as collector. Lime is used as a regulator of pH, meanwhile, and can stabilize special potential very well, and this special potential is exactly the flotation potential of galena. This technology has been applied successfully in potential control flotation of galena in many complex lead zinc iron sulfide mines in China.展开更多
Through thermodynamic calculation and electrochemistry analysis, taking the galena as example, the basis for collector matching in origin potential flotation （OPF） was studied. The results of thermodynamic calculati...Through thermodynamic calculation and electrochemistry analysis, taking the galena as example, the basis for collector matching in origin potential flotation （OPF） was studied. The results of thermodynamic calculation show that the upper limit value of pH and flotation potential of diethyldithiocarbamate （DDTC） is higher than that of xanthogenate （KBX）, which indicates that the collecting ability of DDTC for galena is better than that of KBX. The results of the interface capacitance analysis show that lead diethyldithiocarbamate （PbD2） is more steady than lead xanthogenate （Pb（BX）2） on the galena surface under the oxidation condition; the resistance analysis shows that D2（DDTC oxidizes into its dimmer） and dixanthogen （BX）2 will occur non-faradic desorption on the pyrite electrode surface when the potentials are above 0.13 V and 0.2 V respectively. A synthetical criterion ΔE of collecting ability and selectivity was proposed. The results predicted by this criterion are confirmed through flotation experiments of ore.展开更多
The electrochemical oxidation of galena in collectorless and collector flotation systems, particularly in strong alkaline media, was studied. The results show that, with pH value higher than 12.5 and potentials below ...The electrochemical oxidation of galena in collectorless and collector flotation systems, particularly in strong alkaline media, was studied. The results show that, with pH value higher than 12.5 and potentials below 0.17 V, the oxidation products of galena are elemental sulfur and HPbO - 2. Elemental sulfur was present on the mineral surface in excess of oxidized lead species due to dissolution of HPbO - 2, which is beneficial to the flotation of galena. Under the same conditions, sphalerite and pyrite were depressed as a result of significant surface oxidation. Diethyldithiocarbamate (DDTC) was found to be the most suitable collector for galena flotation in strongly alkaline media. The very potential produced hydrophobic PbD 2-the surface reaction product of DDTC with galena, is 0 to 0.2 V. Meantime DDTC can depress the surface over oxidation of galena. Investigations also indicate that, in the range of -0.9 V to 0.6 V, hydrophobic PbD 2 can be firmly adsorbed on galena.展开更多
文摘In the light of the knowledge gained by the study of electrochemical flotation for galena and selective flotation of galena from lead zinc iron sulfide ores, a technology for accurate potential control based on intrinsic electrochemical behavior in grinding flotation systems has been developed and is called "Original Potential Flotation (OPF)". The optimum conditions for the original potential flotation of galena from Pb Zn Fe sulfide ores are as follows: pH values of 12.5 12.8, potential of 150 180 mV and with diethyldithioncarbamate (DDTC) as collector. Lime is used as a regulator of pH, meanwhile, and can stabilize special potential very well, and this special potential is exactly the flotation potential of galena. This technology has been applied successfully in potential control flotation of galena in many complex lead zinc iron sulfide mines in China.
文摘Through thermodynamic calculation and electrochemistry analysis, taking the galena as example, the basis for collector matching in origin potential flotation （OPF） was studied. The results of thermodynamic calculation show that the upper limit value of pH and flotation potential of diethyldithiocarbamate （DDTC） is higher than that of xanthogenate （KBX）, which indicates that the collecting ability of DDTC for galena is better than that of KBX. The results of the interface capacitance analysis show that lead diethyldithiocarbamate （PbD2） is more steady than lead xanthogenate （Pb（BX）2） on the galena surface under the oxidation condition; the resistance analysis shows that D2（DDTC oxidizes into its dimmer） and dixanthogen （BX）2 will occur non-faradic desorption on the pyrite electrode surface when the potentials are above 0.13 V and 0.2 V respectively. A synthetical criterion ΔE of collecting ability and selectivity was proposed. The results predicted by this criterion are confirmed through flotation experiments of ore.
文摘The electrochemical oxidation of galena in collectorless and collector flotation systems, particularly in strong alkaline media, was studied. The results show that, with pH value higher than 12.5 and potentials below 0.17 V, the oxidation products of galena are elemental sulfur and HPbO - 2. Elemental sulfur was present on the mineral surface in excess of oxidized lead species due to dissolution of HPbO - 2, which is beneficial to the flotation of galena. Under the same conditions, sphalerite and pyrite were depressed as a result of significant surface oxidation. Diethyldithiocarbamate (DDTC) was found to be the most suitable collector for galena flotation in strongly alkaline media. The very potential produced hydrophobic PbD 2-the surface reaction product of DDTC with galena, is 0 to 0.2 V. Meantime DDTC can depress the surface over oxidation of galena. Investigations also indicate that, in the range of -0.9 V to 0.6 V, hydrophobic PbD 2 can be firmly adsorbed on galena.
