Abstract: An improved apparatus and method for recovering metallic silver from solutions containing silver ions by reducing silver ions and oxidizing an element in the electromotive series above silver, such as iron. The apparatus provides plug flow of solution into the reaction media and thereby eliminates the principal cause of channelling and premature failure of the media. A distribution chamber distributes solution uniformly to a porous pad of tangled threads or fibers ahead of the media. This ensures a planar flow front of solution as it enters and passes through the media. In a preferred embodiment, the pad is resilient and is supported by a highly open grating. By eliminating the flow and pressure imbalances or gradients at the entry to the media which are inherent in previous apparatus designs, the invention prevents or greatly retards the onset of channelling or plugging of the media.

Abstract: A waste solution containing heavy metals tightly bound by complexing agents such as EDTA, NTA, and thiosulfate is treated by contacting the solution with a mixture of peroxide and ozone to oxidize and destroy the complexing agents thereby facilitating separation and recovery of the heavy metals and reducing pollution of streams by the heavy metals.