Mn recovery from medium grade ore using a waste cellulosic reductant

Abstract

<smarttagtype namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="metricconverter"> Medium grade siliceous manganese ore containing 38.22% Mn was leached in sulphuric acid medium using shredded newspaper as reducing agent. Objective of the present study was to investigate the effectiveness of ligno-cellulosic base wastes such as used newspaper as a reducing agent. The experimental parameters chosen for this study were: H₂SO₄ concentration (2-5% <i style="">v</i>/<i style="">v</i>), temperature (60-90^oC), reductant to ore ratio (0.4-1) and ore particle size (57 – 274 µm). Optimum conditions for >90% extraction were: 90^oC, 5% H₂SO₄ (<i style="">v/v</i>), reductant to ore ratio 0.5, 8 h, 10% pulp density and ore particle size -100 <img src='/image/spc_char/micro.gif'>m. Newspaper was found to be equally effective as a reducing agent for low grade ore (15.83% Mn) also wherein the amount of reductant and acid needed were proportional to Mn content of the ore<b style="">. </b>The leach solution was enriched to 87 g/L by recycling process. The enriched solution was purified by <i style="">p</i>H adjustment to 4.7 using 20% lime slurry. MnSO₄.H₂O was crystallized from purified solution. A schematic flow-sheet has been included. </smarttagtype>