강정신 교수

The current electrolytic processes for magnesium (Mg) metal have several disadvantages, such as anhydrous magnesium chloride (MgCl2) preparation and generation of harmful chlorine (Cl2) gas. To overcome these drawbacks, a novel Mg production process to produce high-purity Mg metal directly from magnesium oxide (MgO) was investigated in this study. The electrolysis of MgO was conducted using a liquid tin (Sn) cathode and a carbon (C) anode in the eutectic composition of a magnesium fluoride (MgF2

A selective chlorination process using magnesium chloride (MgCl2) as chlorinating agent was investigated with the aim of developing a process for removing iron directly from ilmenite, which is a low-grade titanium ore known as FeTiO3. Two crucibles, one consisting of titanium ore and the other consisting of a mixture of titanium ore and MgCl2, were placed in a gas-tight quartz tube, and then both crucibles were heated to 1000 K. In some experiments, H2O vapor was introduced in the quartz tube. H

A green and effective electrolytic process was developed to produce high-purity Mg metal using primary and secondary resources containing MgO as a feedstock. The electrolysis of various MgO resources was conducted using a Cu cathode in MgF2 – LiF – KCl molten salt at 1043 K by applying an average current of 1.44 A for 12.5 h. The electrolysis of calcined North Korean magnesite and seawater MgO clinker yielded Mg alloys of MgCu2 and (Cu) phases with current efficiencies of 89.6–92.4%. The electro

For the production of high-grade titanium dioxide (TiO2) directly from titanium ore (Ti ore), a fundamental study on the development of a novel carbo-selective-chlorination method using titanium tetrachloride (TiCl4) as a chlorinating agent was carried out. In order to selectively remove iron directly from low-grade Ti ore (mainly FeTiO3), Ti ore and carbon powder were set in a gas-tight quartz tube that was then placed in a horizontal furnace to react with TiCl4 at 1100 K. In the experiments, v

In this study, a novel Mg production process for producing high-purity Mg metal from dolomite was developed. When the electrolysis of calcined dolomite was conducted using Cu cathode and C anode in MgF2 – LiF molten salt at 1083–1173 K by applying an average current of 1.42–1.46 A for 9.50–21.0 h, the current efficiency of 66.4–88.6% was obtained. The produced Mg alloys consisted of MgCu2 and Cu (Mg) or MgCu2 and CuMg2 phases, depending on the Mg concentration in the Mg alloy. When the electroly

Spent selective catalytic reduction (SCR) catalyst installed in power and incineration plants is used to convert nitrogen oxide (NOx) gas to nitrogen (N2) gas. Currently, most spent SCR catalyst in South Korea is eventually discarded in landfills. Recently, a novel and efficient recycling process has been developed to recover tungsten (W), vanadium (V) and titanium (Ti) from spent SCR catalyst. In this process, after soda-melting reactions between the spent SCR catalyst and sodium carbonate (Na2

The measurement and evaluation of MgO solubility in the molten fluoride system is of significant importance in the recently proposed magnesium electrolysis reduction process. In the present study, an in-situ quantitative method of evaluating the concentration of dissolved MgO in molten fluoride is proposed. The MgO solubility in the 32.8MgF2–67.2LiF system was measured at 1083 and 1123 K using a combustion analyzer. MgO saturation was achieved in under 2 h, and higher solubilities were observed

In this study, the deoxidation process for off-grade titanium (Ti) sponge using magnesium (Mg) metal with a wire mesh strainer type of crucible was developed. Ti hydride (TiH₂) feedstock, which was prepared by hydrogenating off-grade Ti sponge, was deoxidized using Mg in a molten magnesium chloride-potassium chloride salt at 933 K under an argon and 20% hydrogen (H₂) mixed gas atmosphere. After deoxidation, the residual Mg-containing salt was separated in situ from the cruc