Process for the Continuous On-Site Production of Percarboxycilic Acid Solutions and Device for Its Implementation

Abstract

Provided are various methods and systems for producing peroxycarboxylic acid compositions, and in particular, nonequilibrium compositions of peracetic acid. The methods and systems control flow rates and proportions of feedstocks/reactants, perform the required sequence of reaction steps to produce high yield peroxycarboxcylic acid solutions in a continuous manner, and provide optimal reaction time and reactant mixing for continuous and safe on-site production.

What is claimed: 
     
         1 . A method for the continuous production of non-equilibrium peroxycarboxcylic acid, comprising:
 a. providing at least one source of water on demand at a point of use of the peroxycarboxcylic acid;   b. providing at least one source of aqueous peroxide;   c. then diluting the aqueous peroxide with the water to generate a diluted aqueous peroxide having a concentration of between 0.1% and 10% and a pH greater than 8;   d. next, providing at least one source of aqueous hydroxide;   e. then, adjusting the pH of the diluted aqueous peroxide to a pH in a range of 10 to 13.5 by adding the aqueous hydroxide source to the diluted aqueous peroxide;   f. providing at least one source of acyl donor; and   h. mixing the at least one sources of acyl donor and dilute aqueous peroxide to produce a single-phase composition of non-equilibrium peroxycarboxcylic acid.   
     
     
         2 . The method of  claim 1 , wherein the at least one aqueous peroxide source is hydrogen peroxide. 
     
     
         3 . The method of  claim 1 , wherein the acyl donor is a liquid acetyl donor. 
     
     
         4 . The method of  claim 1 , wherein the acyl donor is selected from the group consisting of asacetin, diacetin, triacetin, acetylsalicylic acid, (β)-D-glucose pentaacetate, cellulose acetate, D-mannitol hexaacetate, sucrose octaacetate, acetic anhydride, N,N,N′N′- tetraacetylethylenediamine (TAED), N-acetyl glycine, N-acetyl-5 DL-methionine, 6-acetamidohexanoic acid, N-acetyl-L-cysteine, 4-acetamidophenol, and N-acetyl-Lglutamine. 
     
     
         5 . The method of  claim 4 , wherein the liquid acetyl donor is triacetin. 
     
     
         6 . The method of  claim 1 , wherein the at least one aqueous hydroxide source is an alkali metal hydroxide solution or an earth alkali metal hydroxide solution. 
     
     
         7 . The method of  claim 1 , wherein the at least one aqueous hydroxide source is a sodium hydroxide solution. 
     
     
         8 . A method of producing non-equilibrium peroxycarboxcylic acid solution on demand at a point of use, comprising:
 a. diluting an aqueous hydrogen peroxide solution having an initial pH with water to a concentration less than 10% (w/w),   b. adding alkali metal hydroxide or alkali earth metal hydroxide, or solutions of alkali metal hydroxide or alkali earth metal hydroxide whereby the pH of the resulting hydrogen peroxide mixture is between 10.5 to 13.0;   c. adding an O-acetyl or N-acetyl donor such that the ratio of hydrogen peroxide to the acetyl donor in the reaction mixture is at least 1, whereby a two-phase mixture is created; and   d. mixing the components until the two-phase mixture changes into a single-phase solution.   
     
     
         9 . The method of  claim 8  wherein the aqueous hydrogen peroxide solution in step a. is diluted to a concentration of less than 6% (w/w). 
     
     
         10 . The method of  claim 8  wherein the O-acetyl or N-acetyl donor is added until the ratio of peroxide to the acetyl group in the reaction mixture is at least 1.5. 
     
     
         11 . The method of  claim 8  further including the step of adding additional peroxide to the solution. 
     
     
         12 . The method of  claim 8  further including the step of adding an acid source to the solution, whereby the pH of the solution is reduced and any reactions in the solution are stopped. 
     
     
         13 . The method of  claim 8  wherein the non-equilibrium peroxycarboxcylic acid solution has an equilibrium constant defined by the equation 
       
         
           
           
               
               
           
         
       
       which is less than 1.8 or greater than 2.5.