Verfahren zur Abtrennung von Galliumchlorid von Eisen(III)-chlorid

Gallium is extracted from a hydrochloric acid solution of concentration 2 to 10 N, preferably 4 to 7 N, containing gallium, iron and optionally aluminium, the ratio of ferric to gallium ions being at least 10, by extracting the solution with a C3 to C6 trialkyl phosphate, especially tributyl phosphate, optionally in an organic solvent, e.g. kerosene, in an amount less than equivalent, i.e. one ion of Fe to three mols. trialkyl phosphate, to the amount of iron in solution. The extraction may be performed countercurrent, multistage. The optimum acid concentration depends on the amount of iron present and is discussed. In the examples, the use of tributyl phosphate in batch and countercurrent processes is described, using the tributyl phosphate neat or diluted with kerosene or ligroin. The organic solvent phase is extracted with water thereby transferring the gallium and iron into the aqueous phase achieving a concentration of the gallium with respect to the iron.