Magnesium oxide (MgO) is an ionic compound, also known as tartar, lamp powder, etc., odorless, tasteless, non-toxic, and a typical alkaline earth metal oxide. It is a white powder at room temperature, with a melting point of 2852 ℃. Magnesium oxide mainly exists in nature in the form of periclase, and is the main raw material for magnesium smelting in industry Light burned magnesium powder 。
With the development of nano material technology, a new type of inorganic material - nanometer magnesium oxide has also developed rapidly. The particle size of nanometer magnesium oxide is 1-100nm, which is mainly used in catalyst, ceramic raw powder, cosmetics and other fields, and has great application prospects. Next, we will briefly introduce some preparation methods of nanometer magnesia powder.
In general, according to the state of powder preparation, various methods can be divided into solid phase method, liquid phase method and gas phase method to desulfurize magnesium oxide
Solid phase method mainly includes mechanical pulverization and solid phase chemical reaction.
Mechanical pulverization is a method that uses the impact, collision, friction and other external forces between the medium and large particle raw materials to crush large particle raw materials into ultra-fine powder, mainly including mechanical ball milling. This method is mainly used to prepare nano materials with high brittleness in actual industrial production, but it is difficult to crush the raw materials to below 100nm by mechanical crushing, and the shape of particles is irregular, and the particle size distribution is also wide, which is difficult to truly meet the industrial requirements.
Solid phase chemical reaction is a method to obtain ultrafine powder by mixing reactants in a predetermined proportion, then grinding, calcining, grinding and other steps. It is a traditional powder preparation method, and the commonly used methods include room temperature solid phase reaction method and low-temperature solid phase reaction method.
The gas phase method developed late, mainly refers to the method that volatilizes metal organic compounds into gas under the condition of reheating, and then precipitates the products through the reaction between gas phase reactants. Gas phase method has many advantages, such as easy control of reaction conditions, easy preparation of nanoparticles with uniform particle size and high purity, but its cost is high, investment is large, and practical industrial application is difficult. Vapor phase method mainly includes vapor reactive deposition (CVD), plasma method, etc.
