System and method for generation of reactive oxygen species and applications thereof

Abstract

Reactive oxygen species formulations as well as methods for making and using such formulations. Reactive oxygen species formulations comprising one or more parent oxidants, such as peroxides, or peroxyacids, and one or more reactive oxygen species (ROS). The formulations optionally contain in addition one or more reactive species other than ROS. The reactive oxygen species and other reactive species when present provide chemical reactivity, oxidative activity and/or antimicrobial activity not provided otherwise by the parent oxidant. The invention provides methods for making such formulation and applications of such formulations. In certain formulations, ROS and other reactive species are generated in situ in the formulation by an activation event, such as a change in pH to an activation pH, a change in temperature, irradiation with electromagnetic radiation or by the addition of one or more precursors or a combination of precursors. In certain formulations, peracid containing precursors are activated by adjusting the pH of the formulation to be within an activation pH range for generation of singlet oxygen. In other formulations, formulations containing peracid and superoxide also evolve singlet oxygen. Formulations containing different combinations of ROS exhibit differences in oxidation activity and antimicrobial activity.

1 - 38 . (canceled) 
     
     
         39 . A method for generating a reactive oxygen species formulation, the method comprising:
 preparing a peracid mixture in an activated pH range of from pH 9.5 to pH 12.5 for gene rating reactive oxygen species including singlet oxygen, the preparing comprising:   mixing an alkaline hydrogen peroxide solution with a molar excess of an acyl donor to hydrogen peroxide at a molar ratio of hydrogen peroxide to acyl donor in a range of from 1:1.25 to 1:4;   during or after the mixing adjusting pH to initially prepare the peracid mixture at a pH in the activated pH range, and comprising hydrogen peroxide at less than 3% of a mass concentration of peracid in the peracid mixture, for generating the reactive oxygen species; and   distributing the peracid mixture at a point of use and at the point of use applying the peracid mixture to a substrate to be subjected to oxidation.   
     
     
         40 . The method of  claim 39 , wherein the reactive oxygen species formulation comprises singlet oxygen and superoxide. 
     
     
         41 . The method of  claim 39 , wherein the acyl donor is an acetyl donor. 
     
     
         42 . The method of  claim 39 , wherein the alkaline hydrogen peroxide solution is generated from the combination of an alkali and a hydrogen peroxide concentrate. 
     
     
         43 . The method of  claim 42 , wherein the alkaline hydrogen peroxide solution is generated using a molar ratio of H 2 O 2  to alkali in the range 1:1.2 to 1:2.5. 
     
     
         44 . The method of  claim 39 , wherein the alkaline hydrogen peroxide solution is generated electrochemically. 
     
     
         45 . The method of  claim 39 , wherein the reactive oxygen species is distributed to the point of use in at least one form selected from the group consisting of a liquid, an ice, a foam, an emulsion, a microemulsion and an aerosol. 
     
     
         46 . The method of  claim 44 , wherein the alkaline hydrogen peroxide solution as electrochemically generated, has a pH in a range of pH 12.0 to pH 13.0, and has a percent weight of hydrogen peroxide in the range of 0.1 to 3 wt %. 
     
     
         47 . The method of  claim 44 , wherein the alkaline hydrogen peroxide solution comprises a molar ratio of superoxide to hydrogen peroxide in a range of from 0.01:1 to 10:1 and a pH in a range from pH 8 to pH 13 
     
     
         48 . The method of  claim 39 , wherein the reactive oxygen species formulation comprises an ORP of 600 mv vs SHE or more. 
     
     
         49 . The method of  claim 39 , wherein the reactive oxygen species formulation comprises an ORP of 700 mv vs SHE or more. 
     
     
         50 . The method of  claim 39 , comprising after the adjusting pH, diluting the peracid mixture. 
     
     
         51 . The method of  claim 39 , wherein the peracid mixture comprises hydrogen peroxide at less than 0.5% of a mass concentration of peracid in the peracid mixture. 
     
     
         52 . The method of  claim 39 , wherein the peracid mixture comprises no detectible level of hydrogen peroxide. 
     
     
         53 . The method of  claim 39 , comprising applying the peracid mixture to the substrate to be subjected to oxidation within a few hours following the adjusting pH to initially prepare the peracid mixture as a pH in the activated pH range. 
     
     
         54 . The method of  claim 39 , wherein the substrate is contained in water to be treated and the applying comprises adding the peracid mixture to the water to be treated. 
     
     
         55 . The method of  claim 39 , wherein the substrate comprises one or more chemical species to be oxidized in the water to be treated. 
     
     
         56 . The method of  claim 39 , wherein the substrate comprises food items during food processing.