Preparation of Rare Earth Metals by Metal Thermal Reduction Method
Metal thermal reduction method is one of the most widely used processes to prepare rare earth metals. It basically involves the reduction of rare earth compounds or ores with carbon or other metals in order to produce the desired rare earth metals. The process is usually conducted in a high temperature environment and requires a variety of specialized equipment such as furnaces, gas burners and cooling reactors.
The process starts off with the oxidation of the rare earths compounds or ores to form their oxide form. The oxide is then mixed with a reducing agent such as carbon and heated in a furnace up to temperatures of around 1200°C. At these high temperatures, the carbon will act as a reducing agent and reduce the oxides to form the rare earth metals.
The metals are then accumulated at the bottom of the furnace and the excess reducing agent is carried off by an inert gas such as nitrogen. In order to separate the metals, they are usually charged into a fluidized bed reactor and then subjected to a controlled cooling process. This process will cause the metals to solidify and they can then be collected and separated. Depending on the size of the particles, a secondary milling process may then be used to break them down further.
Once the metals have been collected, they can then be purified using various methods. These methods can include distillation, chemical precipitation, electrowinning, ion exchange and solvent extraction. After purification, the final product will be a pure sample of the desired rare earth metals.
The metal thermal reduction method is relatively simple and has a low cost compared to other rare earth metal preparation methods. It can also be used for the production of refractory metals such as tungsten and molybdenum which otherwise require more complex and expensive preparation methods. Furthermore, the process can be scaled up to larger operations and is generally considered to be a safe process with minimal environmental impacts.
Overall, the metal thermal reduction method is an attractive and cost-effective way to prepare rare earth metals. Not only is the process simple and requires minimal specialized machinery, but it can also be used to prepare refractory metals as well. The only downside is that the process requires high temperatures which increases both the risk of fires and the cost of operation. Despite this, the method is still an attractive option for many who wish to produce rare earth metals in an economical manner.
