Activated alumina contains the elements aluminum and oxygen. If the alumina raw material is chemically treat to remove oxides such as silicon, iron, and titanium, the resulting product is high-purity alumina raw material. Below is an introduction to its smelting and purification process:

1. The main raw material for smelting activated alumina is industrial aluminum hydroxide, whose melting point increases with the increase of industrial aluminum hydroxide content, generally between 1700 and 1900 ℃, while the melting point of the product is 2050 ℃. During the smelting process, not only does the furnace charge need to melt. Therefore, the temperature of the electric furnace melt must be maintain above 2050 ℃.
2. During the smelting and purification process, the melting of aluminum hydroxide in the electric furnace is largely localize. The electrical energy delivered to the furnace is basically divide into two aspects: one is high-temperature arc heat, mainly used to melt furnace materials; The second is the resistance heat of the melt, which mainly increases the temperature of the melt to facilitate the smooth progress of chemical reactions.
3. During the smelting process, the furnace charge is roughly divide into three layers. The upper layer is the roasting layer, the middle layer is the sintering layer, and the lower layer is the melting layer, and the three material layers are not completely separate. This is also the reason why sampling and adjusting furnace materials must be at regular intervals during the smelting process.