Basic Chloride Method for Extracting Aluminum from Clay

摘要

As part of a program to devise alternative technologies for producing alumina from domestic resources, the Bureau of Mines investigated the leaching of calcined kaolinitic clay to form basic aluminum chloride solutions. Bench-scale experiments were conducted for single-stage batch leaching with AlCl3 solution and three-stage countercurrent leaching with substoichiometric HCl. Variable conditions of clay calcination and leaching were studied to determine their effects on aluminum extraction and pregnant liquor composition. In comparison with the leaching operation in an HCl-clay process, the basic chloride system offers substantial advantages in energy consumption and equipment size requirements.