Hydrometallurgical Processing of Manganese Ores: A Review

Abstract

Hydrometallurgy is the most suitable extractive technique for the extraction and purification of manganese as compared to all other techniques including biometallurgy and pyrometallurgical processes. In the hydrometallurgical processing of manganese from its ore, the leach liquors often contain divalent ions such as iron, manganese, copper, nickel, cobalt and zinc along with other impurities which make manganese very difficult to separate. The processes employed for solution concentration and purification in the hydrometallurgical processing of manganese include precipitation, cementation, solvent extraction and ion exchange. Solvent extraction also proves more efficient and it plays vital roles in the purification and separation of the manganese as compared to all other techniques. A detailed review of the various steps involved in the hydrometallurgical manganese processing, concentration and purification processes and newer processes of extraction of manganese from ores and waste materials were discussed.

Reductive Leaching of Low-Grade Pyrolusite with Formic Acid

“…But a less expensive and more environmentally friendly bioleaching process is being expected with a higher leaching efficiency. [13] For the low-or middle-grade pyrolusite, hydrometallurgy is extensively applied in the reduction of quadrivalence manganese because of its efficiency and economy. Generally, there are three kinds of hydrometallurgical reductants: organic materials including glucose, [14][15][16] sucrose, [17] cellulose, [18] and methanol [19] ; inorganic materials including pyrite, [20] hydrogen peroxide, [21] and sulfur dioxide [22] ; biomass including molasses [23] and molasses alcohol wastewater, [24] sawdust, [25] corncob, [26] dried leaves, [27] waste tea-leaves, [28] and so on.…”

Counter-Current Leaching of Low-Grade Laterites with Hydrochloric Acid and Proposed Purification Options of Pregnant Solution

“…The main processes for PLS purification include precipitation, solvent extraction, and ion exchange. Precipitation takes place when the chemical species exceed their limit of solubility by changing the solution pH or temperature, or by adding a reagent [15]. Solvent extraction presents high selectivity and involves mixing of PLS with an organic phase; the resulting emulsion is allowed to separate, and the valuable metals are transferred to the organic phase [11,16,17].…”

“…Solvent extraction presents high selectivity and involves mixing of PLS with an organic phase; the resulting emulsion is allowed to separate, and the valuable metals are transferred to the organic phase [11,16,17]. The use of ion-exchange media, such as resins, zeolite, and active carbon, in order to exchange cations or anions from a solution, presents high recoveries and is environmentally friendly, but these media have limited efficiency in mixed stream solutions [15].…”

“…Nickel and cobalt were precipitated as oxides at an operating temperature of~170 • C. Zhang et al [2] applied hydrolytic distillation on synthetic laterite-leaching solutions and showed that 95.5% of iron was removed as hematite, 94% of Ni and Co remained in the aqueous phased as soluble chlorides, and excess HCl was distilled with a final recovery in the order of 77.9%. The removal of Mn and Mg constitutes another significant challenge for PLS purification treatment [15,17].…”

Characterization of Sumbawa manganese ore and recovery of manganese sulfate as leaching products

“…This raw manganese mineral source has not yet been developed optimally. Naturally, manganese ore can be found as pyrolusite (MnO 2 ), psilomelane (BaMn 9 O 16 (OH) 4 ), dan manganite (Mn 2 O 3 H 2 O), haussmannite (Mn 3 O 4 ), Rodhochrosite (MnCO 3 ), dan Rhodonite (MnSiO 3 ) [1]. Sometimes manganese ore are also found together with others minerals such as quartz, kaolinite, dolomite, cordierite [2], hematite and lithiophorite [3].Well-known methods to process manganese ore are pyrometallurgy, hydrometallurgy and biometallurgy.…”