Synthesis, Properties, and Applications of High Purity Hydrate and Alumina

摘要

Low soda or high purity hydrates/alumina with less than 0.1% Na_2O by weight are high-tech materials having extremely special and versatile high-tech applications. When calcined, they are used especially in electronics applications for making high-end refractories and ceramics and are precursor materials for activated aluminas used for catalysts supports. Caustic soda is one of the main impurities in alumina and has an undesirable effect on alumina properties when used in specific applications The paper thoroughly explains the origin, mechanism, and factors affecting the formation of caustic soda in alumina hydrate. It gives an overview of the special hydrate/alumina and reviews comprehensively the manufacturing processes, properties, and vast applications of these special products. It also gives an insight into a process developed by JNARDDC for its production of 3N (99.9%) purity alumina. The paper would largely help in identifying the existing knowledge gap and surely assist in the production of these advanced materials.