Arsenic is a harmful associated element in antimony ore, which might bring out the risk of leakage during complex industrial production of high-purity antimony. Herein, we reported a novel and efficient way to remove the trace arsenic impurity from acidic SbCl 3 solution by utilizing copper-system bimetallic particles. Specifically, galvanically coupled Cu 2 Sb/Cu was in-situ synthesized by introducing precursor copper powder to the specific SbCl 3 solution. DFT studies revealed that Sb(III) was easily reduced by Cu to form Cu 2 Sb due to the strong adsorption of Sb(III) on Cu (111) crystal plane. The Cu 2 Sb/Cu coupling exhibited excellent activity for As(III) reduction, over 99.4% arsenic were removed under optimal conditions and residual arsenic concentration dropped to only 2.7 mg L −1 . Crucially, Sb(III) concentration changes could be neglected. Besides, the dearsenization residues were extensively characterized to analyze the evolvement and cause in the reaction process. The results confirmed that the arsenic removal mechanisms by Cu 2 Sb/Cu particles were multi-affected, including adsorption, displacement, and precipitation. And the strong electrostatic attraction of AsO + under high HCl conditions was identified as a key step to achieving dearsenization. This research will provide a theoretical guidance for the green synthesis of high-purity antimony and related products.
Fu Chengcheng,Ru Juanjian,Hua Yixin,Xue Yu,Bu Jiaojiao,Wang Zhiwei,Zhang Yuan
For the decontamination of Pb in a contaminated Sb alloy, the separation behaviors of Sb and Pb are investigated in choline chloride-ethylene glycol deep eutectic solvent (ChCl-EG DES) at 323–363 K. Linear sweep voltammetry measurements are recorded for determining the electrochemical behaviors of Sb and Pb in a 0.1-M SbCl 3 +ChCl-EG solution. The oxidation potentials of Sb and Pb are + 0.021 V and − 0.05 V at 323 K, respectively, which implies that the addition of SbCl 3 benefits the dissolution of Sb, while that of Pb is opposite. In addition, the reduction potential of Sb(III) is more positive than that of Pb(II), which suggests that the separation of Sb from the Pb-containing Sb alloy is feasible. The effects of temperature and current density are discussed during the electrorefining process. The results show that high-purity Sb powders (99.978%) can be obtained at 30 mA cm −2 and 343 K, and that the current efficiency is about 95.42%.