Leaching Rates for the Hcl Extraction of Aluminum from Calcined Kaolinitic Clay.
Olsen-RS; Bullard-SJ; Gruzensky-WG; Et Al
The Bureau of Mines is engaged in research to recover aluminum from kaolinitic clay and other nonbauxitic domestic resources. As part of this work, calcined Georgia kaolin was prepared by a process that prevents slime formation and makes the leached residues fast settling and easy to filter. The leching reaction for calcined kaolinitic clay in a 5 pct stoichiometric excess of boiling 23- to 26-pct hcl was found to be zero order. Rate constants based on the weight-fraction of aluminum in the clay were found to be between 0.095 and 0.15 Min-1 depending on feed preparation and leaching parameters. The mathematical relationships between aluminum extraction and time for both batch and continuous, stirred-tank operations were derived and verified experimentally.
IH; Report of Investigations