氧化酸浸脱砷及稳定化固砷研究

Study on Arsenic Removal with Oxidative Acid Leaching and Stabilization of Arsenic-bearing Material

采用氧化酸浸法对高砷冶金废渣进行处理,确定了最佳脱砷工艺。结果表明,在硫酸浓度1mol/L、液固比4∶1、20℃反应4h时,滤渣中砷残留量降低到1%以内。向高砷浸出液中加入还原铁粉进行预处理,并用二价铁氧气氧化法合成晶型良好的砷酸铁固砷材料,经毒性浸出试验检测,完全满足SPLP毒性浸出试验要求,可安全处置。

Oxidative acid leaching technology was applied to treat high-arsenic content metallurgical wastes.The results show that arsenic in solid residues falls to 1%or less under the conditions including sulfuric acid concentration of 1 mol/L,L/S=4/1,20℃,and reaction time of 4 h.The filtrate with high-arsenic is pretreated by reduced iron powder before ferric arsenate with good crystal shape is synthesized by oxidation of ferrous sulfate solution.The arsenic-containing material meets SPLP leaching toxicity test and can be disposed safely.