| Metallic lead is widely used in national production and life, especially in the application of lead battery and anti-corrosion protective sleeve, etc. Currently, the main production method of lead is first to obtain crude lead alloy by pyrometalurgical smelting, then the alloy will get the high purity metallic lead by electrolysis refining. However, the silicofluoric acid electrolyte used in electrolytic refining has a more strong corrosion resistance and volatile, not any that, It is very strict with antimony content of crude lead anode about electrolytic process (the content is advisable to 0.4%～0.8%). Moreover, there was much difficult to separate the alloy that by pyrometallurgical process in Guangxi brittle sulfur lead antimony, the Deep Eutectic Solvents (DESs) is expected to overcome the problems existing in the traditional production method, and it will realize separated from lead-antimony alloy that have high antimony.The Acetamide-Ethylene glycol (1C2H5NO:nEG) Deep Eutectic Solvents is synthesized for the first time. And the DESs melting point, viscosity, conductivity, density and thermal stability and other physical and chemical properties has been studied. The DESs has the lowest eutectic point-57℃ when the molar percentages of EG is 80%; As the temperature elevated, the viscosity and density of system decreased, but the conductivity increased; the more higher the percentage of EG was, the lower the electrical conductivity and viscosity was. Ultimately,1:2 was the most suitable molar ratio of C2H5NO with EG by selected, and found that 1 C2H5NO:2 EG DES has a thermal stability within 126 ℃.Via contrastive experiments, choiced Pb(SCN)2 and KSCN as lead salt and conductive salt, and then dissolved them into 1C2HsNO:2EG DES as the electrolyte.The electrolytic separation experiment of lead antimony alloy began With KSCN/Pb(SCN)2/1C2H5NO:2EG DES as the electrolyte, titanium plate as cathode, lead antimony alloy (5% Sb) as anode. The single factor experiment results showed that:when the current density was 3 mA·cm-2, electrolyte temperature was 50 ℃, the mixing speed was 300 r·min-1, the concentration of KSCN and Pb (SCN)2 were respectively 0.6 mol·L-1 and 0.1 mol·L-1 and electrolytic cycle was 17 h, the purity of cathode lead powder could got more than 99.996%, of which current efficiency of electrolysis process was higher than 92%, and the DC power consumption is only about 80.0 kW·h·t-1; When the antimony content of crude lead alloy anode was increased to 20%, cathode lead was still more than 99.98% by electrolytic refining.The electrochemical window of 0.6 mol·L-1 KSCN/1C2H5NO:2EG DES is 2.97 V, which can meet the requirements of electrolytic separation of lead antimony alloy. Cyclic voltammetry curve showed that the reaction process of 0.6mol·L-1 KSCN/0.1mol·L-1Pb(SCN)2/1C2H5NO:2EG DES was Pb-2e?Pb2+, and is quasi reversible reaction controlled by the diffusion process; Anodic polarization curves showed that the lead oxidation peak current density was greater than the antimony, and the lead initial oxidative potential was in preference to antimony, the initial oxidation potential difference of the two is E=0.43 V, it is greater than silicofluoric acid aqueous solution of 0.34V; Cathodic polarization curves found that the reductive reaction of Sb3+ before Pb2+ in the cathode, but the lead reduction peak current density was greater than antimony. And the Pb2+ reduction reaction was Pb2++2e? Pb; Current-Time curve shows that the growth mode of lead was by three-dimensional instantaneous nucleation mode crystal on the titanium electrode.
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