Decrease of Iron Content of Bauxite Through High Temperature Chlorination

Selective Fe extraction from Hungarian bauxite of low grade was studied in the temperature range of 600-850 deg C, in a Cl flow, using a batch chlorination device and a fluidized bed of laboratory scale. A reduction of Fe sub 2 O sub 3 content from 16.8 to 3-3.5% was achieved. The results of structure analytical methods (DTG, X-ray diffractometry, Mossbauer spectroscopy, and EDAX, etc.) proved that acidic extraction and the chlorination studied are suitable only for extracting that part of the Fe content, which is in hematite or in goethite form, while the Fe content built into the mineral structure, having an oxidation degree of three and co-ordination number six, cannot be removed by these methods. The previous reduction or sulphidation of the samples before Fe reducing chlorination also only affected the hematite phase. This means that the method tested is suitable only for Fe content reduction and not for total Fe extraction. Graphs, Spectra. 16 ref.--AA