Industrial Alumina Powder High Purity: 98.6% Application area: aluminum,corundum,ceramic,refractories and so on. Industrial Alumina Powder No.ItemUnitSpecificationFirst gradeSecond grade1Al 2 O 3 ( % )≥98.698.42SiO 2 ( % )≤0.020.043Fe 2 O 3 ( % )≤0.020.034Na 2 O ( % )≤0.50.65Loss of ignition %≤1.01.0Application area :aluminum,corundum,ceramic,refractories and so on. Alumina