Chlorine dioxide generation for water treatment
First Claim
Patent Images
1. A method of forming an aqueous solution of chlorine dioxide, which comprises:
- feeding an aqueous solution of sodium chlorite to an anodic compartment of an electrochemical cell divided by at least one ion-permeable separator from a cathode compartment to which water or an aqueous electrolyte is fed,electrochemically generating a first aqueous solution of chlorine dioxide in the anodic compartment of said electrochemical cell in the presence of about 20 to about 450 gpL of sodium chlorate,contacting said aqueous solution of chlorine dioxide with one face of a hydrophobic microporous membrane, andproviding a differential of partial pressure of both said chlorine dioxide and water vapor between said aqueous solution and an aqueous recipient medium in contact with the opposite face of said hydrophobic microporous membrane, whereby both chlorine dioxide and water vapor pass through the membrane to the recipient medium to form a second aqueous solution of chlorine dioxide as the product.
4 Assignments
0 Petitions
Accused Products
Abstract
Chlorine dioxide is generated by electrochemical oxidation of sodium chlorite in an anode compartment of a cation-exchange membrane-divided cell in the presence of significant quantities of sodium chlorate and is recovered in a suitable recipient medium by passing the chlorine dioxide through a hydrophobic microporous membrane. Water balance in a continuous operation is maintained by removing water from the anolyte by transporting the same partly across the hydrophobic microporous membrane in vapor form and partly across the cation-exchange membrane.
86 Citations
7 Claims
-
1. A method of forming an aqueous solution of chlorine dioxide, which comprises:
-
feeding an aqueous solution of sodium chlorite to an anodic compartment of an electrochemical cell divided by at least one ion-permeable separator from a cathode compartment to which water or an aqueous electrolyte is fed, electrochemically generating a first aqueous solution of chlorine dioxide in the anodic compartment of said electrochemical cell in the presence of about 20 to about 450 gpL of sodium chlorate, contacting said aqueous solution of chlorine dioxide with one face of a hydrophobic microporous membrane, and providing a differential of partial pressure of both said chlorine dioxide and water vapor between said aqueous solution and an aqueous recipient medium in contact with the opposite face of said hydrophobic microporous membrane, whereby both chlorine dioxide and water vapor pass through the membrane to the recipient medium to form a second aqueous solution of chlorine dioxide as the product. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
Specification