Hydrochloric acid leaching of calcined kaolin to produce alumina.
Poppleton HO; Sawyer DL Jr.
Proc 106th AIME Ann Mtg Atlanta, Georgia, 3/77 Light Metals 1977 Feb; 2:103-114
The federal Bureau of Mines, joined by industry in a cost-sharing cooperative effort, is conducting a minipilot plant program designed to provide a comparative evaluation of methods for recovering alumina from domestic nonbauxitic resources. As part of the program, it has been demonstrated that alumina can be extracted from kaolinitic clay, using 26 pct hydrochloric acid for digestion. Aluminum chloride hexahydrate is crystallized from the leach solution and is subsequently decomposed to alumina and hydrogen chloride, which is recycled. The hcl miniplant operation is described; alumina extractions of more than 90 pct have been achieved. The process flowsheet is presented, materials of construction are described, and problem areas are discussed.
OP; Conference/Symposia Proceedings
Proc. 106th AIME Ann. Mtg., Atlanta, Georgia, 3/77; Light Metals, V. 2, Feb., 1977, PP. 103-114