Pt of pickling liquid waste, Pd, Rh metal recovery process

摘要

PURPOSE: To recover a catalytic metal from a pickling soln. obtained by incorporating a catalyst such as Pt ion, Pd ion and Rh ion into hydrochloric acid and selectively adding NO₃^- ion and which has been used for pickling a steel- base metal. ;CONSTITUTION: A steel-base metal is pickled by a pickling soln. obtained by incorporating Pt ion, Pd ion and Rh ion or further NO₃^- ion into hydrochloric acid, and Cr⁶⁺ ion is added to the waste pickling soln. in the form of K₂Cr₂O₇, CrO₃, etc. When ≥90% of Pd and Rh are recovered, Cr⁶⁺ ion (g/l) ≥22.5+3.75×T (°C) should be kept, and Cr⁶⁺ ion (g/l) ≥52.5+3.75×T (°C) should be kept when ≥40% Pt, Pd and Rh are recovered.;COPYRIGHT: (C)1993,JPO&Japio