Preparation of Spherical Sub-Micron Alumina from Hainan Kaolin

It is an effective way to prepare alumina by replacing bauxite with aluminous minerals. It was studied that the preparation of spherical sub-micron alumina from Hainan kaolin by alginate assisted dispersion. The results of the experiment showed that the alumina content in Hainan kaolin is more than 38%. The t process parameters as of extracting alumina by acid leaching were optimized by uniform design optimization method. The alumina extraction rate reached more than 97% with optimized process conditions. It was used as aluminum source material that he aluminum salt obtained from Hainan kaolin was treated with impurity removal. With this source material, and the purified alginate AG was used as dispersant，the α- Alumina powder with good sphericity, uniform dispersion and average particle size of about 350 was prepared.