Recovery and purification of copper sulfide nanoparticles from acid mine drainage by biological sulfate reduction and microfiltration using low-cost ceramic membrane

Acid mine drainage (AMD) typically has a high amount of copper that can be recovered in pure form for different industrial applications. This study combined metal bioprecipitation and microfiltration for recovering copper from AMD in a highly pure form. Different pretreatment methods were also evaluated to obtain copper sulfide nanoparticles (CuSNPs) in pure form, and probe sonication proved the most effective. Microfiltration using the ceramic membrane showed 92% separation efficiency of CuSNPs. Following its separation, the nanoparticles were characterized using different techniques such as Fourier transform infrared spectroscopy, X-ray diffraction and field emission transmission electron microscopy. The pure CuSNPs were polycrystalline in nature with a size in the range 5-10 nm. The size, shape, and crystallinity of the CuSNPs revealed its excellent industrial reuse and application potential. Furthermore, based on the cost of the raw materials used to prepare the membrane, the membrane cost was estimated to be $160/m(2). [GRAPHICS] .