Magnesium oxide (MgO) is an ionic compound, also known as magnesia, light powder, odorless, non-toxic, is a typical kind of alkaline earth metal oxides, which is a kind of white powder at room temperature, the melting point is 2852 DEG C, Magnesium Oxide in nature mainly exist in the form of periclase is mainly. The raw material of magnesium smelting industry.
With the development of nanomaterial technology, a new type of inorganic material, nano Magnesium Oxide, has been developed rapidly. The particle size of nano Magnesium Oxide is 1-100nm, which is mainly used in the fields of catalyst, ceramic powder, cosmetics and so on. It has a great application prospect. The following is some brief introduction about preparation method of nanometer magnesium oxide powder.
In general, according to the state of preparing the powder, various methods can be divided into solid state method, liquid phase method and gas phase method.
The solid phase method mainly includes mechanical pulverization and solid state chemical reaction.
Mechanical comminution is a way to break large particles into ultrafine powders by external force such as impact, collision and friction between medium and large particles, including mechanical ball milling and so on. This method is mainly used for the preparation of nano materials with high brittleness in the actual industrial production. However, it is very difficult to break the raw materials to below 100nm by mechanical comminution, and the shape of particles is irregular and the particle size distribution is wide. It is difficult to really achieve the industrialization requirements.
Solid chemical reaction refers to the reactants were mixed in a predetermined proportion, then grinding and calcining and crushing steps and get a method of ultrafine powder, which is prepared by a traditional method of powder system, commonly used methods include solid state reaction at room temperature and low temperature solid state reaction method.
The development of gas phase method is relatively late. It mainly refers to the way of volatilization to gaseous state under the condition of reheating of metal organic compound, and then precipitate by reaction between gaseous reactants. Gas phase method has many advantages, for example, the reaction conditions are easy to control, and the nanoparticles with uniform size and high purity are easy to be prepared. However, the cost is high and the investment is large, so the industrial application is rather difficult. Gas phase method mainly includes gas phase reactivity deposition (CVD), plasma method and so on.