Magnesium oxide produced by Haicheng Huasheng Refractory Company

Magnesium oxide produced by Huasheng refractory is composed of 41%, 44%, 45%, 46%, 47% content of magnesite, brucite and magnesium hydroxide extracted from seawater or brine by calcination at 800~1000 °C. It is decomposed to discharge CO2 or H2O, that is, to obtain magnesium oxide, also known as light burnt magnesia, caustic magnesia or light burnt magnesium, commonly known as bitter soil powder. Light burnt magnesium powder is loose in texture and chemically active. It can be used for the manufacture of magnesium cement, magnesite building materials, thermal insulation materials, etc. It is also an intermediate product of high-quality magnesia produced by two-step calcination.

    When magnesite is heated, equiaxed crystals of periclase appear around 600 °C; equimolar crystals of periclase disappear at 650 °C, and non-equal sodal magnesia is produced; equiaxed crystals of periclase at 850 °C Completely disappear. These periclase crystal lattices have higher surface energy due to point defects and dislocations. The lattice of MgO is not much larger than that of the MgCO3 lattice group, so the inter-lattice pores are increased, the porosity is high, the specific surface area is large, and the activity is high.

The light burning temperature and light burning time of magnesite have a certain influence on the activity of light burned magnesium powder. The magnesite is calcined at 600, 650, 700, 750, 800, 850 and 900 ° C, respectively, and the calcination temperatures of 700, 750 and 800 ° C in 15 to 90 minutes have no significant effect on the activity of the light burned magnesium powder; The effects of 600, 650, 850 and 900 °C on the activity were particularly significant. When calcined at 600 and 650 °C, the activity increased significantly with time; the activity at 850 and 900 °C calcined decreased with the prolongation of hydrocarbon burning time.

    Light burnt magnesium powder is light yellow and light brown powder, the particle size is mostly below -100 mesh, the crystal of calcite is very small (<3μm), the true specific gravity is 3.07~3.22, the accumulated bulk density is 0.8~1.2g/cm3, and the refractive index is 1.68. ~1.70, large lattice constant (α=0.4212), many lattice defects, crunchy texture, pore structure, large reactivity, easy solid phase reaction or sintering, and Mg(HO)2 hardening with water. Bonding ability. The calcined magnesia powder calcined from magnesite has a volume shrinkage of about 5%; usually 3% to 5% of CO2 remains due to incomplete decomposition.