Hebei Messi Biology Co., Ltd. stated that it uses the sol-gel method to prepare nano-magnesium oxide using magnesite, hydrochloric acid and urea as raw materials, and adding the gelling agent polyethylene glycol. The effects of calcination temperature, gelling agent molecular weight, dispersing agent and their dosage on the experiment were investigated. The results show that the suitable conditions for preparing nano-magnesium oxide are: polyethylene glycol as gelling agent, dispersant, and calcination temperature. Under these conditions, nanometer magnesium oxide with a purity of 99%, small average particle size, nearly spherical uniform distribution, and good activity was obtained.
Hebei Messi Biology Co., Ltd. stated that the ammonium chloride solution is directly used to perform a metathesis leaching reaction with brucite to first obtain the magnesium chloride leachate, and at the same time absorb the ammonia produced by the reaction with water; then the magnesium chloride leachate and the recovered ammonia are subjected to a magnesium precipitation reaction to obtain an intermediate Magnesium hydroxide, and finally the magnesium hydroxide is calcined at high temperature to produce high-purity magnesium oxide. The ammonium chloride generated during the magnesium precipitation reaction can be recycled.
The influence of various factors on the magnesium leaching rate during the brucite leaching process was studied. The leaching temperature is, the solid ratio leaching time is, and the leaching rate is above. By controlling the temperature and DH value of the reaction between the magnesium chloride solution and ammonia, the filtration can be obtained , the filter cake with good washing performance has a moisture content of only 1%, and the purity of the magnesium oxide obtained by high-temperature calcination reaches 99%.
Nanoscale magnesium oxide has obvious small size effect, surface effect, quantum size effect and macro tunnel effect. After modification, there is no agglomeration phenomenon. It has many special functions and important application value in optics, catalysis, magnetism, mechanics, chemical industry, etc. , the prospect is very broad and it is an important new material in the 21st century.