Chromium and zinc removal and recovery by ion exchange
AssigneePetro-Metals Recovery Systems Limited
InventorsTerrence I. Scott, Vincent H. Westlake, Michael K. Bridle
Life of this patent
Estimating the term…
Abstract
In the removal of chromium and zinc, the combination of an anion exchange resin and cation exchange resin in a single vessel, the anion exchange resin being selective of chromium in its chromate and dichromate ionic forms, and the cation exchange resin being an intermediate acid cation exchange resin with a phosphonic acid functional group on a cross-linked polystyrene matrix, having the repeating structural formula: ##STR1## selective of zinc in its ionic form, said single vessel, having distributors selected from the group of inlet distributors, regenerant distributors, subsurface washers, collectors, disposed therein, and inlets and outlets for the addition or removal of effluent, water and regenerant.
Claims35
In a process for the selective recovery from effluent, of zinc and chromium in their ionic forms, by ion exchange, the step of passing the effluent through a fixed bed of anion exchange resin and cation exchange resin, in the same ion exchange vessel, the anion exchange resin being selective of chromium and the cation exchange resin being an intermediate acid cation exchange resin with a phosphonic acid functional group on a cross-linked polystyrene matrix having the repeating structural formula:
- ##STR6## selective of zinc.
A process for the selective recovery of zinc and chromium in their ionic forms from effluent, including the steps of combining an intermediate acid, cation exchange resin with phosphonic acid functional group on a cross-linked polystyrene matrix, having the repeating structural formula:
- ##STR7## with an anion exchange resin selective of, or having an affinity for, chromium in its ionic forms in a fixed bed in a single vessel, passing effluent containing chromium and zinc in their respective ionic forms therethrough and regenerating the resins into their useful forms, in the same vessel.
Dependencies are inferred from the claim text.