在線聊天
Calcined alumina
Brand: henan
Net weight: 50 kg/bag
Specification: 325 mesh
Aluminum oxide, chemical symbol: Al2O3, molecular weight 102, pure alumina is a white amorphous powder, commonly known as alumina, 3.9 4.0 g/cm3 density, melting point 2050 ℃, boiling point 2980 ℃, insoluble in water, for both sexes oxide, soluble in inorganic acid and alkaline solution, and there are four kinds of isomer with element beta-alumina delta - - a - alumina, alumina v are alpha and gamma two variations, industry can be extracted from bauxite.
?
In the lattice type alpha alumina, oxygen ions as the six-party close packing, Al3 + symmetrically distributed in oxygen ion of octahedral coordination center, lattice energy is very big, therefore, a high melting point, boiling point. Alpha alumina insoluble in water and acid, also known as alumina industry, is the basic raw material of aluminum; Also used for making all kinds of firebrick, refractory crucible, fire pipe, high temperature resistant experiment instrument; Can also be abrasive, flame retardants, fillers, etc; The alpha type of high purity alumina or production of raw materials of synthetic corundum, synthetic ruby and sapphire; Also used in the production base of modern large scale integrated circuit board.
?
Gamma alumina is aluminum hydroxide in the dehydration system of 140-150 ℃ low temperature environment, industry also called activated alumina, aluminium glue. Oxygen ion in the structure approximation is made in heart tightly packed, Al3 + irregularly distributed in octahedral surrounded by oxygen ions and tetrahedral gap. Gamma alumina insoluble in water, soluble in acid or alkali solution, will it all into a heated to 1200 ℃ alpha alumina. Gamma alumina is a porous material, the inside surface area per gram of up to hundreds of square meters, high active adsorption ability. Industrial products usually colorless or microstrip pink cylindrical particles, good pressure resistance. In petroleum refining and petrochemical industry is a commonly used adsorbent, catalyst and catalyst carrier; In industry is the transformer oil, turbine oil, acid agent, also used for chromatographic analysis; Strong desiccant is neutral in the laboratory, the drying capacity as phosphorus pentoxide, use after 6 to 8 h under 175 ℃ heating regeneration reuse.
?
Currently using bayer process of alumina production in the world want to account for over 90% of the total output, most of alumina used for aluminum, as less than 10% for other USES
