Thermodynamic simulation and validation experiment of neodymium oxide reduction into metallic neodymium by metallothermic process

Abstract

Neodymium (Nd) is one of the rare-earth elements (REEs) found in significant amount within monazite and bastnasite minerals. Nd is a ferromagnetic metal that is often used as a material to produce magnet, commonly known as a permanent magnet. Neodymium is alloyed with other metals such as iron and boron to form one of the strongest types of permanent magnet. This research aim is to study the reduction process of Nd-oxide into Nd-metal through the metallothermic process. The Nd metal product is expected to fulfill the material specification for a permanent magnet. Thermodynamics simulation of Nd reduction into its metal was conducted using ITB"s licensed Factsage software. A validation experiment was conducted only to the Nd metal resulting simulation. The simulations involved some parameters, i.e. temperatures (600, 700, 800, 900, 1000, 1100 and 1200 °C), types of fluxes (CaCl2 and Ca(OH)2), composition of the reducing agent (1x, 2x dan 3x of the stoichiometric calculations), types of the reducing agents (Ca and Mg), and types of feeds used (Nd-oxide and Ndchloride). The thermodynamic simulation shows that Nd metal was produced in a condition where the temperature should be1100-1200 °C using Ca as the reducing agent and CaCl2 as the flux, while the amount of reducing agent has no effect on the resulted product. Validation result of the simulations shows that the Nd metal is formed up to 49% metal in a non-oxidative condition.

High Contact Resistivity Enabling Low‐Energy Operation in Cr2Ge2Te6‐Based Phase‐Change Random Access Memory

“…[ 16 ] It is known that IA–IIIB elements tend to show low work functions below 4.0 eV, [ 18 ] but these elements are difficult to use in practical applications because they are chemically reactive, e.g., easily oxidized. [ 19 ] Another material, LaB 6 , is also known as a workable electrode material, with a low work function (2.8 eV), which is much lower than that of a typical W electrode (4.55 eV) and chemically stable. [ 20,21 ] Therefore, a high ρ c is expected at a LaB 6 /CrGT interface that is free of interfacial reactions, as shown in Figure .…”

“…oxidized. [19] Another material, LaB 6 , is also known as a workable electrode material, with a low work function (2.8 eV), which is much lower than that of a typical W electrode (4.55 eV) and chemically stable. [20,21] Therefore, a high ρ c is expected at a LaB 6 /CrGT interface that is free of interfacial reactions, as shown in Figure 1.…”

A Study on the Production of Anhydrous Neodymium Chloride through the Chlorination Reaction of Neodymium Oxide and Ammonium Chloride

“…Among the carbon-free smelting processes, metallothermic reduction, which produces metals through the direct reaction of metal oxides with reducing agents such as Ca and Mg, offers the advantage of reduced operational steps owing to the simplified process steps and the possibility of producing products in the form of alloys, which also allows for reduced process temperatures. However, the generation of slag via the combination of a reducing agent and oxygen during the reaction process requires additional processes to recycle the slag after operation [7]. One way to prevent slag generation is to convert metal oxides into metal salts through chlorination or fluorination reactions and use them as raw materials (Nd sources) for metal manufacturing.…”