| An innovative technology has been developed to treat complex antimony lead concentrate. Technological and fundamental researches have been conducted systematically and in detail. The mechanism of anodic reactions and leaching reaction of antimony-lead concentrate in Slurry Electrolysis assumed with experimental results.I . Laboratory and pilot tests of all technological process have been accomplished systematically and in detail.Slurry Electrolysis Technology by using HC1 - NH4C1 medium with high solubility of SbCl} and low solubility of PbCl? has been used to treat complex antimony lead concentrate. This solution system is very suitable to treat antimony-lead concentrate in Slurry Electrolysis Process, in which antimony can be extracted in priority and the separation of antimony from lead is realizable.Using Slurry Electrolysis Process with HC1-NH_|C1 solution to treat antimony-lead concentrate, the optimum conditions were determined by laboratory tests as: NH4C1 200g/L, HC1 Imol/L, temperature 60癈, [Sb]T 30-50g/L, [Fe]T 3^8g/L, liquid-solid ratio 5~~10:1, anodic current density 150~200A/m2. As oxidizer, the coulomb is theoretical coulomb to leach antimony out + theoretical coulomb to oxide Fe2~, which exist in anode area.The pilot tests in a single 2.5m"1 Slurry Electrolysis Cell demonstrated that the construction of Slurry Electrolysis Cell was reasonable. The leaching of antimony, silver, iron, arsenic and sulfur are up to 97%, 20%, 20%, 15% and 15%, respectively. Average DC electricity consumption is 1377kWh per ton cathode antimony produced, hydrochloric acid consumption is 280kg-per ton concentrate treated, and water expand does not exist.Converting the residue of Slurry Electrolysis with ammonium carbonate and then removing sulfur with kerosene can recover lead concentrate with about 50% Pb and less than 16% S and elemental sulfur. Lead and silver in theconcentrate can be extracted in lead smelting. P204 can be used to remove ferric ions from HC1-NH4C1 solution. The extraction of FeJ+ reaches to more than 98.4%; antimony, arsenic and silver remain in raffmate. The iron concentration of raffmate is below 3g/l and the raffmate can be recirculated to Slurry Electrolysis. N235 is employed to treat the stripped solution of P2o4, and the regenerated HC1 solution can be used as the stripping solution of loaded P2o4 organic in circle.The recovery of all are as fellow: Sb 95%, Pb 95%, Ag 80%, S 60% ?To minimize silver concentration in leaching solution, KI is added due to the lower solubility of Agl. And the leaching of silver can be controlled below 20%.II . Fundamental researches have enriched the fundament of Slurry Electrolysis.The solubility of SbCl3, PbCl2 and AgCl in HC1 - NH4C1 solution has been measured preliminarily. This solution system has the advantage of high solubility of SbCl3 and low solubility of PbCkThe leaching of complex antimony lead concentrate is very complicated. Tests show that it can be leached via dissolving of non-oxidative and oxidative complex acid, chemical oxidation, and anodic oxidation during Slurry Electrolysis. Under the condition of Slurry Electrolysis, the primary anodic reaction is the ferrous ion oxidation on the anode, and the ferric ions are main oxidant of antimony-lead concentrate. However, the concentrate particle oxidation on the anode exists during the whole Slurry Electrolysis process. With the help of mineralogical study of the Slurry Electrolysis residues, it can be considered that the major anodic oxidation and leaching reaction of jamesonite is:Sb6Pb4FeS14+ 28Fe3" =6Sb3++ 4Pb2> 29Fe2+ + 14S?And the direct oxidation reaction of jamesonite particle on the anode surface exists also:Sb6Pb4FeS14 -28e = 6Sb3++ 4Pb2++ Fe2' + 14S0On the basis of the study of anode electrochemistry, if the anodic potential (r\) is between 60mv and HOmv, the anodic oxidation of Fe2+ is controlled by electrochemically reaction. If r) is between lOOmv and 180mv, it is controlled by mixed reaction. If r\ is between 160mv to 220mv, it is co...
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