Removal and recovery of copper from substantially cyanide-free alkaline waste solutions

Abstract

Abstract PROCESS FOR THE REMOVAL OF SUBSTANTIALLY ALL COPPER FROM A SUBSTANTIALLY CYANID-FREE ALKALINE WASTE SOLUTION CONTAINING IONIC COPPER, A REDUCING AGENT, FOR EXAMPLE FORMALDEHYDE, FOR THE IONIC COPPER WHICH IS ADDED TO THE SOLUTION IF NOT ALREADY PRESENT THEREIN, AND USUALLY A COMPLEXING AGENT FOR THE IONIC COPPER. THE PROCESS ALSO PROVIDES FOR THE RECOVERY OF MARKETABLE ZERO VALENT METALLIC COPPER. THE ALKALINE WASTE SOLUTION IS CONTACTED WITH A MATERIAL OR METAL CATALYTIC TO THE REDUCTION OF THE IONIC COPPER BY THE REDUCING AGENT TO ZERO VALENT METALLIC COPPER, AND THE CATALYTIC CONTACTING CONTINUED UNTIL THE DESIRED AMOUNT OF COPPER IS PRECIPITATED AS ZERO VALENT METALLIC COPPER. THE METALLIC COPPER PRECIPITATE IS THEN SEPARATED, FOR INSTANCE BY FILTRATION, FROM THE SOLUTION. EXEMPLARY OF THE CATALYSTIC METALS FOR USE IN CATALYZING THE REDUCTION OF THE IONIC COPPER TO ZERO VALENT METALLIC COPPER ARE PALLADIUM, PLATINUM, BOLD AND SILVER.

Inventors

• 👤 Edward B Saubestre

Bibliographic Details