Reductive recovery of manganese from low-grade manganese dioxide ore using toxic nitrocellulose acid wastewater as reductant

摘要

The hydrometallurgical strategy of extracting Mn from low-grade Mn ores has attracted attention for the production of electrolytic manganese metal (EMM). In this work, the reductive dissolution of low-grade MnO~(2)ores using toxic nitrocellulose acidic wastewater (NAW) as a reductant was investigated for the first time. Under the optimized conditions of an MnO~(2)ore dosage of 100 g·L_(?1), an ore particle size of ?200 mesh, concentrated H~(2)SO~(4)-to-NAW volume ratio of 0.12, reaction temperature of 90°C, stirring speed at 160 r·min_(?1), and a contact time of 120 min, the reductive leaching efficiency of Mn and the total organic carbon (TOC) removal efficiency of NAW reached 97.4% and 98.5%, respectively. The residual TOC of 31.6 mg·L_(?1)did not adversely affect the preparation of EMM. The current process offers a feasible route for the concurrent realization of the reductive leaching of Mn and the treatment of toxic wastewater via a simple one-step process.