The Recovery of Soluble Copper from an Industrial Chemical Waste

A novel electrochemical device was used to recover copper metal from an inorganic chemicals process effluent. In a sidestream pilot-plant demonstration, the copper content was continuously reduced from an average of 20 mg/l to less than 2 mg/l. The basic concepts, laboratory testing, and pilot-plant demonstration are described. General Future water-pollution regulations may require effluent concentration limits for heavy metals more restrictive than the Public Health Service drinking water standards. Such regulations would severely limit the allowable levels of copper, lead, silver, chromium, mercury, and manganese in plant effluents. Parallel with this development is the increasing scarcity of the world's mineral r!"-:!rces including metals such as these. The simplest form of any pollution abatement-resource recovery system would have two key features: reduction of the contaminant content of an effluent to a level meeting regulatory standards, and recovery of the contaminant in concentrated form suitable for recycle or sale. The technologies of chemical precipitation, solvent extraction, ion exchange, cementation, and reverse osmosis have all been considered for treating specific , effluents containing such metals. There are practical limitations, however, in i aP$ving these methods: high cost, inadequate heavy-metals rerroval to meet ' h. .ening standards, lack of information on acceptable ultimate disposal of 1 removed metals, or insufficient technical data on how a particular treatment method is affected by other components in the effluent. Moreover, except 1 _for reverse osmosis, these methods generally require continued addition of