METHOD AND INSTALLATION OF METAL RETRIEVING FROM USED CHROMING SOLUTIONS

摘要

The invention concerns a method or procedure and an installation of metal retrieving from used water chroming solutions, with high content of Cr and other impurifying metals as Fe, Cr<3+>, Cu, using as reactive the gas ammonia, introducted at the base of the reaction tub, through a detachable device, connected to a gas contained through a flexible tube. The technology consists in the reduction of the acidity of the used solution, from PH = 0,5 to a PH of 5.5, in the same time with the precipitation of the impurifying metals as insoluble hydroxydes non toxic and re-usable, as well as the separation of the Cr<6+> as water solution of ammonia dychromate.