Separation of ferromanganese ore components by non-contact and contact carbothermic reduction

The possibility of joint selective solid-phase reduction of iron and phosphorus in ferromanganese ore has been experimentally confirmed. The experiments were carried out in a Tamman laboratory furnace at a temperature of 1000 °C and holding for two and five hours. The article presents results of the study of phase composition and phases' quantitative ratio of the reduction products, as well as chemical composition of the phases. It was established that reduction roasting in CO atmosphere provides a transition from oxide phase to metal phase only of iron and phosphorus. At the same time, the concentration of manganese oxide MnO increases in the ore oxide phase. The use of solid carbon as a reducing agent under the same conditions leads to transition to the metallic phase together with iron and phosphorus of a part of manganese. Based on the obtained data, it is proposed to selectively reduce iron and phosphorus at a temperature of 1000 °C with a reducing gas. Gas reduction will make it possible to use existing gas furnaces, in particular, multi-pod furnaces, for metallization of iron and phosphorus in ferromanganese ore, and natural gas, including hydrogen -enriched gas, and even pure hydrogen, as a reducing agent and energy carrier. Due to this, at the stage of ore metallization in production of manganese alloys, greenhouse gas CO2 emissions can be reduced. The results of the work can be used in the development of theoretical and technological bases for processing ferromanganese ores with a high content of phosphorus, which are not processed by existing technologies.

An overview on potential hydrometallurgical processes for separation and recovery of manganese

With rapid economic progress worldwide, the search for new resources for materials has become a priority due to mineral resource depletion. Enhanced requirements for manganese alloys and compounds for several commercial applications created a desperate demand for manganese recovery technologies from primary as well as secondary resources. The future demand for manganese alloys and compounds is expected to increase. The growing need of electrolytic manganese dioxide (EMD) for different battery usage in automobile and energy sectors could create a gap in the supply and demand of manganese. There is an urgent necessity for eco-friendly and efficient technologies to boost the production of manganese from low-grade ores as well as post-consumer products. The framework of effective leaching processes and proper solvent extraction techniques for the recovery of manganese could be a novel pathway to get a clean, green and healthy environment for a sustainable future in the automotive and energy segment where this metal has a significant contribution.

Detecting quadrupole: a hidden source of magnetic anisotropy for Manganese alloys

Mn-based alloys exhibit unique properties in the spintronics materials possessing perpendicular magnetic anisotropy (PMA) beyond the Fe and Co-based alloys. It is desired to figure out the quantum physics of PMA inherent to Mn-based alloys, which have never been reported. Here, the origin of PMA in ferrimagnetic Mn3− δ Ga ordered alloys is investigated to resolve antiparallel-coupled Mn sites using x-ray magnetic circular and linear dichroism (XMCD/XMLD) and a first-principles calculation. We found that the contribution of orbital magnetic moments in PMA is small from XMCD and that the finite quadrupole-like orbital distortion through spin-flipped electron hopping is dominant from XMLD and theoretical calculations. These findings suggest that the spin-flipped orbital quadrupole formations originate from the PMA in Mn3− δ Ga and bring the paradigm shift in the researches of PMA materials using x-ray magnetic spectroscopies.

Thermodynamic and Experimental Study on Efficient Extraction of Valuable Metals from Polymetallic Nodules

Polymetallic nodules are promising resources for the extraction of valuable metals such as copper, nickel, and cobalt, as well as manganese alloys. To achieve efficient extraction of useful metals from the emerging resource, high-temperature carbothermic reduction of nodules was investigated by optimizing the reductant addition, slag and alloy systems. Thermochemical software FactSage was used to predict the liquidus temperature of the slag system, which is not sensitive to FeO, CaO and Al2O3, but decreases significantly with decreasing MnO/SiO2 mass ratio. The experiments were designed to reduce the oxides of Cu, Co and Ni completely, and reduce FeOx partially depending on the amount of graphite addition while leaving the residual slag for further processing into ferromanganese and/or silicomanganese alloys. Co, Cu and Ni concentrations in the alloy decreased with increasing graphite addition. The optimal reduction condition was reached by adding 4 wt% graphite at the MnO/SiO2 mass ratio of 1.6 in slag. The most effective metal-slag separation was achieved at 1350 °C, which enables the smelting reduction to be carried out in various furnaces.

High-Quality Low - Phosphorous Manganese Alloys for Production of Steel of Low-Temperature Reliability

The problem of enrichment and dephosphorization of poor manganese ores for receiving the low-phosphorous alloys necessary for smelting of steel of low-temperature reliability is considered.

Preparation and Usage of High Quality Manganese-Containing Materials from Ferroalloy Production Waste

We propose a flow diagram for processing ferroalloy production waste, such as silicothermic slag from manganese metal, as well as wet and dry powder of cleaning gas from ferroalloy furnaces that smelt manganese alloys. We experimentally determined the parameters for intensifying the calcium chloride method of enriching ferroalloy production waste, which resulted in a manganese extraction rate of 78-86%, with high-quality manganese concentrates. We present the results of studies related to the use of high-quality concentrates to dope steel with manganese, when processing it in a bucket, and smelting manganese metal via the aluminothermic method.