SDS和PVP强化生物淋溶锰渣的性能

在生物淋溶锰渣的过程中,设置一系列浓度梯度(0～100 mg/L)的离子型表面活性剂SDS(十二烷基硫酸钠)和非离子型表面活性剂PVP(聚乙烯吡咯烷酮),研究两种活性剂对硫杆菌生长和对锰渣中锰的浸出率的影响.结果表明,两种表面活性剂均能有效强化硫杆菌对锰渣的淋溶性能,SDS和PVP的最佳浓度分别为35 mg/L和15 mg/L,在最佳浓度条件下,两者均能显著降低培养液的pH值,提高锰的浸出率,其浸出率分别达到88％和83％,均高于对照组的72％.进一步分析表明,SDS比PVP更能有效提高浸出体系的ORP电位,促进锰的浸出.电镜结果表明,在最佳浓度条件下,SDS比PVP更能有效促进硫杆菌对锰渣表面的侵蚀,降低锰渣的表面粒度,提高锰渣中锰的浸出率.

SDS and PVP enhanced biological leaching of manganese in manganese slags

Different concentrations(0~100 mg/L)of ionic surfactant SDS(sodium dodecyl sulfate)and non-ionic surfactant PVP (polyvinyl pyrrolidone) were added to the culture medium in the leaching process, and the effects of two kinds of surfactants on the grown of acidithiobacillus ferrooxidans and manganese leaching rates were investigated. The results indicated that both surfactants can effectively strengthen ferrooxidans on manganese slags leaching properties and the optimum concentrations of SDS and PVP are 35 mg/L and 15 mg/L, respectively. Under the best concentration conditions, the pH values of the culture medium significantly decreased, but the leaching rates increased. The leaching rates reached 88% and 83% under the best concentration conditions, respectively, which were both higher than the control group (72%). The SDS was found to be more effective for improving manganese leaching and promoting ORP than PVP. Electron microscopy shows that SDS can promote the ferrooxidans on manganese slags surface erosion more effectively, reducing the particle size of manganese slags surface, and increasing the leaching rate of manganese.