Cu, As, Sb and Bi in copper electrolyte could be efficiently removed by reducing with SO2 followed by evaporative crystallization. As2O3 and CuSO4·5H2O were obtained after crystallized product was treated by dissolution, oxidation, neutralization, sedimentation, filtration and evaporative crystallization. The removal rates of Cu, As, Sb and Bi are 87.1%, 83.9%, 21.0% and 84.7%, respectively, when As （Ⅴ） in copper electrolyte is fully reduced to As （Ⅲ） by SO2, and the H2SO4 in concentrated copper electrolyte is 645 g/L. The removal rate of As is 92.81% when 65 g crystallized product is dissolved in 200 mL water at 30 ℃. The CuSO4·5H2O content is 98.8% when the filtrate is purified under the conditions that n（Fe）：n（As） is 1.2, the dosage of H2O2 is 19 times the stoichiometric needed, temperature is 45 ℃, time is 40 min, pH is 3.7, and then is evaporation crystallized.
Cu and As were separated and recovered from copper electrolyte by multiple stage electrowinning, reduction with SO2and evaporative crystallization. Experimental results showed that when the current density was 200 A/m2, the electrolyte temperature was 55 °C, the electrolyte circulation rate was about 10 mL/min and the final Cu concentration was higher than 25.88 g/L, the pure copper cathode was recovered. By adjusting the current density to 100 A/m2 and the electrolyte temperature to 65 °C, the removal rate of As was 18.25% when the Cu concentration decreased from 24.69 g/L to 0.42 g/L. After As（V） in Cu-depleted electrolyte was fully reduced to As（Ⅲ） by SO2, the resultant solution was subjected to evaporative crystallization, then As2O3 was produced, and the recovery rate of As was 59.76%. The cathodic polarization curves demonstrated that both Cu2＋ concentration and As（V） affect the limiting current of Cu2＋ deposition.
采用均相水溶液聚合法,以新型水溶性低温偶氮化合物VA-044作为引发剂合成用于赤泥沉降的聚丙烯酸钠絮凝剂。通过正交优化实验确定聚丙烯酸钠合成的最佳条件为:反应温度40℃;引发剂用量0.06%;单体浓度40%;链转移剂0.0002%。该条件下制得的聚合产物特性粘数可达到1050 m L·g-1。采用红外光谱对合成产物进行检测,红外图谱显示聚合产物为聚丙烯酸钠。通过赤泥沉降实验测试其絮凝性能,结果表明自制絮凝剂SP1最佳沉降速度可达到44.18 m·h-1,总体絮凝效果优于Alclar 665絮凝剂。
