Leaching rates for the HCl extraction of aluminum from calcined kaolinitic clay.
Olsen-RS; Bullard-SJ; Gruzensky-WG; Mrazek-RV; Henry-JL
Albany, OR: U.S. Department of the Interior, Bureau of Mines, RI 8744, 1983 Feb; :1-11
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.
Leaching; Aluminum oxide; Kaolinite; Hydrometallurgy; Extractive metallurgy; Hydrochloric acid; Aluminum
IH; Report of Investigations
NTIS Accession No.
Albany, OR: U.S. Department of the Interior, Bureau of Mines, RI 8744