Performic acid on-site generator and formulator

• US 10,172,351 B2
• Filed: 09/01/2016
• Issued: 01/08/2019
• Est. Priority Date: 09/04/2015
• Status: Active Grant

• Current Assignee: Ecolab USA Incorporated (Ecolab, Inc.)
• Original Assignee: Ecolab USA Incorporated (Ecolab, Inc.)
• Inventors: Kraus, Paul R., Crew, Benjamin, Li, Junzhong, McSherry, David D., Balasubramanian, Ramakrishnan, Staub, Richard, Kleczewski, Ariel Chatman, Tran, Minh, Hanson, Catherine, Yunus, Irwan, Breshears, Jeffery D., Brunner, Brian Paul
• Primary Examiner(s): Chorbaji, Monzer R
• Application Number:
  US15/254,559
• Publication Number:
  US 20170064949A1
• Time in Patent Office: 859 Days
• Field of Search: 422129, 422256, 422300
• CPC Class Codes: A01N 37/16 containing the group; Thio analogues thereof
• CPC Class Codes: A01N 37/36 containing at least one carboxylic group or a thio analogue, or a derivative thereof, and a singly bound oxygen or sulfur atom attached to the same carbon skeleton, this oxygen or sulfur atom not being a member of a carboxylic group or of a thio analogue, or of a derivative thereof, e.g. hydroxy-carboxylic acids
• CPC Class Codes: A23L 3/3463 Organic compounds; Microorganisms; Enzymes
• CPC Class Codes: A23L 3/3481 Organic compounds containing oxygen
• CPC Class Codes: A23L 3/3499 with doubly-bound oxygen
• CPC Class Codes: A23V 2002/00 Food compositions, function of food ingredients or processes for food or foodstuffs
• CPC Class Codes: B01J 19/1812 Tubular reactors
• CPC Class Codes: B01J 19/1818 in series
• CPC Class Codes: B01J 19/2415 Tubular reactors
• CPC Class Codes: B01J 2219/00051 Controlling the temperature
• CPC Class Codes: B01J 2219/00094 Jackets
• CPC Class Codes: B01J 2219/00132 using electric heating or cooling elements
• CPC Class Codes: B01J 2219/00144 Sunlight; Visible light
• CPC Class Codes: C07C 407/00 Preparation of peroxy compounds
• CPC Class Codes: C07C 409/24 the —O—O— group being bound between a >C=O group and hydrogen, i.e. peroxy acids
• CPC Class Codes: C07C 51/367 by introduction of functional groups containing oxygen only in singly bound form
• CPC Class Codes: C23F 11/10 using organic inhibitors
• CPC Class Codes: Y02W 10/37 using solar energy

Abstract

Methods of generating performic acid by contacting aqueous oxidizing agent and aqueous formic acid source in liquid phase are disclosed. A system and apparatus for the in situ production of the performic acid chemistries is further disclosed. In particular, a continuous flow reactor is provided to generate performic acid at variable rates. Methods of employing the oxidizing biocide for various disinfection applications are also disclosed.

Claims

1. An adjustable biocide generator system for on-site performic acid forming composition generation comprising:

an apparatus comprising at least one inlet, a length of pipe, a heating device, and an outlet for dosing a performic acid forming composition from said length of pipe;

wherein said inlet(s) are in fluid connection with said length of pipe and supply reagents to produce said performic acid forming composition in said length of pipe;

wherein said reagents comprise a formic acid source and an oxidizing agent;

wherein said reagents undergo degasification in the inlet(s); and

wherein said length of pipe is in fluid connection with said outlet to dispense said performic acid forming composition.

2. The system according to claim 1, wherein said performic acid forming composition is an individual or mixed performic acid forming composition according to a user- or system-inputted selection, and wherein the mixed performic acid forming composition comprises performic acid and an additional C1-C22 percarboxylic acid.

3. The system according to claim 1, wherein the formic acid source is formic acid, and wherein said oxidizing agent is 1-50% w/v hydrogen peroxide.

4. The system according to claim 1, wherein the reagents do not include a chelating agent, stabilizing agent and/or chemical catalyst.

5. The system according to claim 1, wherein the reagents further comprise a corrosion inhibitor and/or an additional biocide selected from the group consisting of gluteraldehyde, THPS, a quaternary amine, and TTPC.

6. The system according to claim 1, further comprising at least one measurement device, wherein said measurement device measure one or more reaction kinetics or system operations for said performic acid forming composition generation.

7. The system according to claim 6, wherein said measurement device is selected from the group consisting of conductivity, weight, flow, pH, pressure, temperature, titrator for reagent concentration and combinations thereof.

8. The system according to claim 1, wherein said heating device is selected from the group consisting of a cartridge, heat exchanger, heat blanket, steam jacket, solar panels, steam preheat, an electrical source and combinations thereof.

9. The system according to claim 1, wherein said heating device maintains a temperature that does not exceed 200°

C. for the reagent temperature, and wherein said length of pipe is designed to accommodate at least 5 times the pressure of the system.

10. The system according to claim 1, further comprising a control software for operating said apparatus to generate a user- or system-inputted performic acid forming composition and desired flow rate of said performic acid forming composition for on-site generation, wherein said control software determines the flow rate and/or timing of feeding of said raw materials to said length of pipe and reaction time required for production of said user- or system-inputted performic acid forming composition and desired flow rate.

11. The system according to claim 1, further comprising a data output means for sharing information related to said performic acid forming composition formulation, performic acid forming composition consumption or usage, additional performic acid forming composition production-related data or combinations of the same.

12. The system according to claim 1, wherein the apparatus further comprises a safety release valve and/or rupture disk to vent the system, and wherein the apparatus comprises at least two inlets, wherein the first inlet doses a formic acid source to said length of pipe and the second inlet doses an oxidizing agent to said length of pipe, and optionally wherein said second inlet does an oxidizing agent to said length of pipe via downward flow.

13. A method of cleaning using an on-site generated performic acid composition comprising:

obtaining a user- or system-inputted performic acid composition on-site using the adjustable biocide generator system of claim 1;

applying said performic acid composition in an amount sufficient to sanitize, bleach and/or disinfect a surface in need thereof.

14. The method of claim 13, wherein the surface is a food item or a plant item and/or at least a portion of a medium, a container, an equipment, a membrane, a system or a facility for growing, holding, processing, packaging, storing, transporting, preparing, cooking or serving the food item or the plant item.

15. The method of claim 13, wherein the performic acid composition is applied to the surface by means of a spray, immersion, foam, or gel.

16. The method of claim 13, wherein the applying step lasts for at least 5 seconds.

17. The method of claim 13, wherein the performic acid composition reduces a microbial population by at least three log₁₀.

18. The method of claim 13, wherein the surface is liquid system, process water, or surfaces of equipment that come in contact with liquid systems.

19. A method of on-site generating performic acid forming composition comprising:

providing a formic acid source to a length of pipe at a desired flow rate;

providing an oxidizing agent to said length of pipe at a desired flow rate;

degasifying said formic acid source and said oxidizing agent in inlet(s) prior to entering said length of pipe;

contacting said formic acid source with an effective amount of said oxidizing agent within said length of pipe in the presence of a heating device to form a performic acid composition;

delivering said performic acid composition to a downstream process, wherein said performic acid is an individual or mixed performic acid composition according to a user- or system-inputted selection,

wherein the reaction to form the performic acid composition begins generating yield instantaneously and reaches maximum yield within 10 minutes or less.

20. The method of claim 19, wherein the formic acid source is formic acid and the oxidizing agent is hydrogen peroxide, and wherein the hydrogen peroxide and the performic acid concentration generated on-site is from 2 wt-% to about 15 wt-% and has a higher concentration to the unreacted hydrogen peroxide.

21. The method of claim 19, wherein said heating device is selected from a group consisting of a cartridge, heat exchanger, heat blanket, steam jacket, solar panels, steam preheat, an electrical source and combinations thereof, and wherein said heating device provides heat sufficient to raise the temperature of the solution within said pipe to a temperature not exceeding about 180°

C.

22. The method of claim 19, wherein said heating device is a cartridge contained with said length of pipe and wherein the difference between said pipe'"'"'s inner diameter and said cartridge'"'"'s diameter is less than about 5 inches.

23. The method of claim 19, further comprising cooling said performic acid to a temperature at or below freezing to stabilize the performic acid composition.

24. The method of claim 19, further comprising a step of:

(a) measuring variables of the reaction to form the performic acid composition, wherein the measuring step measures conductivity, temperature, product levels, concentrations, IR/UV/VIS spectroscopy, pressure, performic acid and/or oxidant concentrations, and/or flow rate; and

/or (b) controlling the method using control software for operating said apparatus to generate a user- or system-inputted performic acid forming composition and said desired flow rate of said performic acid forming composition for on-site generation.

25. The method according to claim 19, wherein the reaction reaches maximum yield within 60 seconds or less, wherein the reaction generates at least about 2% performic acid near instantaneously, the reaction generates at least about 4% performic acid within 1 minute, the reaction generates at least about 8% performic acid within 2 minutes, or the reaction generates at least 15% performic acid within 30 minutes.