Three-Chamber Chlorine Dioxide Generator with Ion-Exchange Membranes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for generating chlorine dioxide are either expensive or involve hazardous reagents that can react inadvertently, posing safety risks and inefficiencies in chlorine dioxide production.
Innovation Solution
A method involving a three-chamber apparatus with cation exchange resin material and a specific ion-exchange reaction that generates chlorine dioxide without a catalyst, using sodium chlorite and sodium hypochlorite with controlled ratios and pH, achieving a 100% theoretical yield and reducing the need for expensive catalysts or hazardous reagents.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If electrolytic methods are used to generate chlorine dioxide, then production cost is reduced, but theoretical yield is limited to 80% due to side reactions forming hydrochloric acid
Solution Approach 1:
The apparatus is divided into three separate chambers (anode chamber, reaction chamber, cathode chamber) connected by ion-exchange membranes. This segmentation allows independent control of chemical reactions in each chamber, enabling the anode to generate chlorine dioxide at 100% theoretical yield while isolating side reactions. The physical separation prevents hazardous reagent interactions and allows optimized chemistry in each compartment.
Solution Approach 2:
Ion-exchange membranes serve as intermediaries between chambers, selectively transporting ions while preventing direct mixing of reagents. The membranes enable controlled ion flow (H+, Na+, OH-) between chambers, facilitating the 100% yield reaction by allowing H+ to reach the reaction chamber without permitting Cl2 or other hazardous intermediates to mix with chlorite solution.
2Productivity
If catalysts are used to improve chlorine dioxide generation, then reaction efficiency increases, but production cost increases due to expensive catalyst materials
Solution Approach 1:
The system uses inexpensive ion-exchange membranes that automatically perform ion transport functions without requiring external catalysts. The membranes self-regulate ion flow based on concentration gradients and electrical fields, eliminating the need for expensive catalytic materials while maintaining high reaction efficiency through optimized chamber design and pH control.
3Productivity
If traditional electrolytic cells with diaphragms are used, then chlorine dioxide can be generated, but hazardous reagents may inadvertently mix causing safety risks
Solution Approach 1:
The three-chamber design physically segments hazardous reagents into separate compartments. The anode chamber contains oxidizing conditions for ClO2 generation, the reaction chamber holds chlorite solution, and the cathode chamber contains reducing conditions. Ion-exchange membranes create selective barriers that prevent direct mixing of incompatible reagents, eliminating safety risks associated with traditional single-chamber electrolytic cells.
Solution Approach 2:
Ion-exchange membranes act as selective intermediaries that allow controlled ion transport while blocking hazardous reagent mixing. The membranes permit passage of small ions (H+, Na+, OH-) necessary for reaction progression while preventing mixing of chlorite, chlorine, and other hazardous species, thus maintaining safety without compromising productivity.
4Ease of manufacture
If ion-exchange resin beds are used to produce chlorous acid, then the process can proceed without catalysts, but the structure of the solid resin undergoes permanent change
Solution Approach 1:
The invention extracts the ion-exchange function from solid resin beads and implements it using thin-film ion-exchange membranes in the three-chamber apparatus. This extraction allows the process to proceed without catalysts while preventing the permanent structural degradation that occurs in resin beds, as the membranes maintain their integrity through selective ion transport without undergoing permanent chemical changes.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method enhances the efficiency and safety of chlorine dioxide production, achieving a higher yield and reducing costs by eliminating the need for catalysts and minimizing hazardous reagent interactions, while allowing for interactive disinfection regimens that optimize disinfection effectiveness.
Implementation Method 1
Each chamber is filled with cation exchange resin material
Implementation Method 2
It is known to produce chlorine dioxide electrolytically by the electro-oxidation of chlorite ions
Implementation Method 3
U.S. Pat. No. 2,163,793 describes an electrochemical chlorine dioxide generating process in which an aqueous solution of alkali metal chlorite and alkali metal chloride is electrolyzed in an electrolytic cell
Data Source
AI summary
The invention is directed to an apparatus and methods of its use to generate chlorine dioxide. The apparatus comprises three cation exchange resin chambers in fluidic communication to convert chlorite salt into chlorine dioxide. Unlike previous converters, the invention utilizes an novel method of acidifying some of the chlorite to produce a more effective process. The invention can achieve a 100% theoretical yield which is s significant improvement over the 80% theoretical yield in previous attempts using non-acidifying chemistry. The method also avoids the need for expensive catalysts.