Development of a process to produce manganese nanomaterials from low grade ferruginous manganese ores

Abstract

ABSTRACT This study has been carried out to explore the feasibility to use the low-grade ferruginous manganese ores to produce manganese nanomaterials (Mn ferrites and ϒ-MnO2). Ore samples were collected from mines and were ground into <250 μm particle size. These samples were leached using a 1.5 M solution of oxalic acid for 6 h at 90°C. The recovered solution was processed through two different routes. In the first method, leachate was photo-reduced for 8 h and the precipitate was roasted at 350–700°C to produce Mn nano ferrites of magnetic saturation of 18.71 emu/g. In the other route, iron was removed by pH adjustment, and MnCO3 was produced using NaHCO3. MnCO3 was roasted and producing 200 nm manganese oxides nanorods. These results show that the low-grade manganese ore resources can be a potential source for production of manganese nanomaterials to fulfil the growing demand.