Preparation And Study Of High-activity Light Burned Magnesia

Magnesite is a very important basic inorganic mineral, its products can be widely used in metallurgy, building materials and chemical industry etc. Although China has rich magnesite resources, but low grade and cryptocrystalline magnesite has not been extensively studied. This topic use Tibet cryptocrystalline magnesite, high-grade phanerocrystalline, low-grade and tailings as raw material, study the relationship between the calcining system and the activity of light burned magnesium. The results are as follows:(1)The 30-50 mm four grade magnesite can get the highest activity when the calcining system is 850℃×2.5h.(2) The 30-50 mm tailings can get the highest avtivity when the calcining system is 750℃×1.5h.(3) The 30-50 mm cryptocrystalline magnesite can get the highest activity when the calcining system is 800℃×2h and the coarse grain magnesite can get the highest activity when the calcining system is 900℃×2h.(4) The activity results of different grain size of four grade magnesite shows that activity increased with increasing temperature below 850℃,when the temperature is above 850℃,the activity decreased.(5) The activity results of different grain size of magnesite tailings shows that activity increased with increasing temperature below 750℃,when the temperature is above 750℃,the activity decreased.(6) The 30-50 mm magnesite tailings can get “The mother salt” when the burning temperature is 600℃.(7) The Cryptocrystalline magnesite has a faster decomposition speed than coarse grain magnesite.(8)The activity of magnesium is affected by its microstructure.(9)The citric acid method is simpler than hydration method.