表面活性剂对钴矿石生物浸出的影响

研究了表面活性剂Tween-20,Tween-80与RB-1181对钴矿石生物浸出的影响.研究结果表明:添加表面活性剂使溶液与矿物的接触角显著减小,溶液对矿物表面的润湿作用增强;当质量浓度小于0.25 g/L时,表面活性剂对细菌的生长没有不利影响,添加表面活性剂试样与空白试样的亚铁离子均在72 h内被氧化完全;添加表面活性剂能够改变中间产物S的表面性质,促进细菌对S的氧化,加速矿物表面钝化层的溶解.进而矿物溶解加速,金属浸出率提高.在矿浆质量分数为10%,浸出温度为45℃,转速为180 r/min的条件下,加入表面活性剂后,钴浸出率可提高34%以上,铜浸出率提高15%以上,强化效果显著.

Catalytic Effects of Surfactants on the Cobalt Ore Bioleaching

The effects of Tween-20， Tween-80 and RB-1181 surfactants on the bioleaching of cobalt ore were investigated. The results showed when the surfactant was employed， the contact angle between the solution and mineral was significantly decreased and the wetting action of the solution to the surface of ores increased. In addition， there were not negative effects on the growth of bacteria in the presence of appropriate concentrations of surfactants with the mass concentration of 0.25g/L， and the oxidation rates of ferrous ions were the same which were fully oxidized within 72hrs with or without surfactants. When surfactants were added， the surface properties of the intermediate product element sulfur were changed and the dispersion of surface passivation element sulfur was enhanced， thus the oxidation of element sulfur by bacteria was improved. As a result， the dissolution of the cobalt ore was accelerated， and the leaching efficiencies of metals were improved. In the presence of surfactants， the leaching efficiency of cobalt increased by approximately 34%， and that of copper increased by approximately 15% under the condition with ore pulp concentration of 10%， leaching temperature of 45℃ and the rotation rate of 180r/min.