Improvements relating to the isolation of germanium

摘要

Germanium values are isolated from dilute solutions in hydrochloric acid by passing the solution through a selective ion exchanger which contains as a structural unit a fluorone derivative of the formula:- p where R is a hydroxyphenyl with 1 or 2 -OH groups, said ion-exchanges having been prepared by condensation of said fluorone derivative with formaldehyde with or without an admixture of monobasic or dibasic phenols; thereupon treating said ion-exchanger and the adhering germanium with pure concentrated hydrochloric acid to remove the impurities, desorbing said ion-exchanger by washing with distilled water, and removing residual HCl from the solution so obtained, for example by electrolytic anodic oxidation. By evaporating the HCl solution pure GeO2 is obtained. This electrolysis may be carried out in a cell which has joint anode and cathode chambers, the whole of the chlorine being evolved on the anode, and the germanium partly separating on the cathode in elemental form and partly remaining in solution. Alternatively the electrolysis may be effected in a cell in which the anode and cathode chambers are separated by a semi-permeable membrane consisting of an anion exchanger, the anode chamber being filled with the desorbate and the cathode chamber with a dilute solution of ammonia, the chlorine being completely evolved at the anode and the whole of the germanium remaining in solution.