ELECTROLYTIC DEVICE FOR GENERATION OF pH-CONTROLLED HYPOHALOUS ACID AQUEOUS SOLUTIONS FOR DISINFECTANT APPLICATIONS

Abstract

An electrolytic device for the generation of hypohalous acid in aqueous solutions includes at least a single liquid chamber for receiving an aqueous solution containing halide ions therein, the single liquid chamber having an exterior wall and a solid anode contained within to provide for the oxidation of the halide ions, which, in turn, provides for the formation of hypohalous acid in aqueous solution, and a gas permeable cathode forming a portion of the exterior wall of the single liquid chamber, the cathode providing for the reduction of oxygen to provide hydroxyl ions in solution within the single liquid chamber to mix with the products generated at the anode. An embodiment of the electrolytic device including an anolyte chamber and a catholyte chamber separated by an ionomeric membrane is also described, whereby the anolyte chamber further includes an outlet including a pH control for determining and regulating the pH of the exiting anolyte effluent to between about 4 and 9. The product is suitable for disinfectant applications including as a hand sanitizer.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a divisional application of U.S. patent application Ser. No. 12 / 243,457, filed Oct. 1, 2008, the disclosure of which is hereby incorporated by reference.TECHNICAL FIELD[0002]The present invention relates to a method for forming hypohalous acid and further relates to at least a single liquid chamber electrolytic device for generation of pH-controlled hypohalous acid aqueous solutions for disinfectant applications. This method and device has the advantage whereby the pH of the solution is regulated and optimized. Such a method and device is particularly useful for preparing hypochlorous acid. Specifically, the resultant effluent exiting the device, which may be HClO in aqueous solution, is suitable for use in hand sanitizers.BACKGROUND OF THE INVENTION[0003]Others have attempted to produce hypohalous acids using a variety of methods. For example, one method of producing low-chloride aqueous solutions of hypochlorous acid...

AI Technical Summary

Benefits of technology

[0018]In the present device, an aqueous solution containing halide ions is introduced into an electrolytic device for generation of pH-controlled hypohalous acid aqueous solutions, whereby at least a single liquid chamber may be utilized in which reactions are taking place at the interface between the each of the electrodes and the electrolyte solution to produce an effluent of HClO in aqueous solution. As reactions are taking place in the presence of excess water, the reactions occurring in the single liquid chamber release an effluent which may be monitored for pH, a desired pH range between about 4 and about 9. This method and device has an advantage in that storage of gaseous species, such as chlorine gas, is not needed. Also, the source electrolyte is economical and safe for handling, while the end product may be directly used for disinfectant purposes at a controlled pH level suitable for use as a hand sanitizer without irritation or damage.

Problems solved by technology

Creating the spray of fine droplets requires high pressures, and thus, a high energy input.

Disadvantages of this process include difficulty in handling the solid salt, high chlorine ratios, and energy inefficiency.

This process suffers from a need to further remove the HClO from the organic solvent to produce an aqueous HClO solution, a need to remove residual solvent from the brine solution, and undesirable reactions of HClO with the organic solvent.

However, the invention necessitates the use of a dual chamber device, and hydrogen peroxide would not be suitable for a daily hand sanitizing formulation.

Chlorine may be provided in multiple forms including chlorine gas (Cl2), a relatively cheap and highly effective antimicrobial agent; however, it is also a highly toxic and corrosive gas.

Hypochlorites, such as NaOCl or Ca(OCl)2, are a much safer alternative, but are considerably more expensive than gaseous chlorine.

Finally, hypochlorite solutions (i.e., bleach) may also be utilized; however, these are rarely used in large scale applications because they are bulky and hazardous.

However, human skin may be damaged by application of acid sterilizing liquid of such a low pH.

It is, however, difficult to control the efficiency of the carbon dioxide gas usage and these processes are inherently inefficient.

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