WO2010034519A2 - Synergistic peroxide based biocidal compositions - Google Patents
Synergistic peroxide based biocidal compositions Download PDFInfo
- Publication number
- WO2010034519A2 WO2010034519A2 PCT/EP2009/006975 EP2009006975W WO2010034519A2 WO 2010034519 A2 WO2010034519 A2 WO 2010034519A2 EP 2009006975 W EP2009006975 W EP 2009006975W WO 2010034519 A2 WO2010034519 A2 WO 2010034519A2
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- hydrogen
- peroxide
- sulfite
- compound
- aqueous system
- Prior art date
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/18—Water
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
- A01N37/00—Biocides, pest repellants or attractants, or plant growth regulators containing organic compounds containing a carbon atom having three bonds to hetero atoms with at the most two bonds to halogen, e.g. carboxylic acids
- A01N37/16—Biocides, pest repellants or attractants, or plant growth regulators containing organic compounds containing a carbon atom having three bonds to hetero atoms with at the most two bonds to halogen, e.g. carboxylic acids containing the group; Thio analogues thereof
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
- A01N59/00—Biocides, pest repellants or attractants, or plant growth regulators containing elements or inorganic compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
- C02F1/722—Oxidation by peroxides
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
- C02F1/76—Treatment of water, waste water, or sewage by oxidation with halogens or compounds of halogens
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/02—Non-contaminated water, e.g. for industrial water supply
- C02F2103/023—Water in cooling circuits
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/42—Nature of the water, waste water, sewage or sludge to be treated from bathing facilities, e.g. swimming pools
Definitions
- the invention relates to a method for controlling microbial growth in aqueous systems containing sulfite and/or bisulfite residues, such as solutions or suspensions obtained after appli- cation of sulfite-based reducing bleaches. It further relates to a method for stabilizing active halogen biocides in peroxide-containing aqueous systems.
- bleaches are frequently used in paper making applications. Such bleaching processes typically employ bisulfite or bisulfite generating solutions. While enhancing paper brightness, the use of such solutions can also result in sulfite residues in the produced pulp. Sulfite residues make pulp preservation and subsequent paper machine deposit control more difficult as many major paper slimicides and preservatives such as dibromonitrilopropionamide, isothiazolinones, and, in particular, oxidizing biocides are unstable in the presence of sulfite.
- microbial growth in an aqueous system containing sulfite and/or bisulfite residues is controlled by adjusting and maintaining a pH >5, preferably pH 6-11, and more preferably 7.5-10, in the aqueous system and adding a peroxy compound.
- Preferred peroxy compounds include hydrogen peroxide, inorganic peroxy compounds such as alkali metal or alkaline earth metal perborates, percarbonates or persulfates, organic peroxy acids such as peracetic or perbenzoic acid, other organic peroxy compounds such as urea peroxide, and mixtures of the beforementioned.
- the term "persulfates” includes both mono- persulfates (i.e., the salts of peroxymonosulfuric acid, H 2 SO 5 ) and peroxydisulfates (i.e., the salts of peroxydisulfuric acid, H 2 S 2 O 8 ).
- the efficacy of the peroxy compounds may be increased by the addition of bleach activators such as tetraacetylethylenediamine (TAED).
- TAED tetraacetylethylenediamine
- a particularly preferred peroxy compound is hydrogen peroxide.
- the pH of the aqueous system can be controlled and/or buffered, if necessary, by addition of bases or basic salts such as alkali or alkaline earth metal hydroxides, carbonates, bicarbonates, borates, metasilicate, or mixtures thereof.
- bases or basic salts such as alkali or alkaline earth metal hydroxides, carbonates, bicarbonates, borates, metasilicate, or mixtures thereof.
- the concentrations of sulfite and/or bisulfite and peroxy compound immediately after addition of the peroxy compound are 1 to 300 ppm each, more preferably 5 to 200 ppm and most preferred 10 to 100 ppm each.
- an active halogen bio- cide in an aqueous system containing peroxides or peroxide residues is stabilized by adding an N-hydrogen compound to the active halogen biocide before combining the biocide with the peroxide containing aqueous system.
- an N-hydrogen compound is an organic or inorganic compound having at least one hydrogen atom directly bound to a nitrogen atom.
- Active halogen biocides are biocides containing halogen, in particular chlorine or bromine, in the oxidation state 0 or +1, such as elemental chlorine or bromine and hypochlorite or hypo- bromite.
- the concentration of active halogen (as Cl 2 ) stabilized by an N-hy- drogen compound is 0.1 to 20 ppm.
- the expression “as Cl 2” denotes the concentration of elemental chlorine that is stoichiometrically equivalent to the concentration of active halogen in a given system.
- N-hydrogen compounds are selected from the group consisting of ammonia, ammonium salts, such as ammonium sulfate and ammonium bromide, other nitrogen compounds containing no carbon-hydrogen bonds, such as urea, biuret, isocyanuric acid, and sulfamic acid, organic N-hydrogen compounds such as p-toluenesulfonamide, 5,5-dialkyl- hydantoins, methanesulfonamide, barbituric acid, 5-methyluracil, imidazoline, pyrrolidone, morpholine, acetanilide, acetamide, N-ethylacetamide, phthalimide, benzamide, succinimide, N-methylolurea, iV-methylurea, acetylurea, methyl allophanate, methyl carbamate, phthalo- hydrazide, pyrrole, indole, formamide, N-methylform
- the ⁇ -hydrogen compound is 5,5-dimethylhydantoin, urea, ammonia, or an ammonium salt.
- the peroxide or peroxide residue in the aqueous system is preferably hydrogen peroxide, an alkali metal or alkaline earth metal percarbonate, perborate, or persulfate, an organic peroxy acid, or a mixture of two or more of the beforementioned, hydrogen peroxide being most preferred.
- Preferred applications of either finding, namely the synergistic performance of peroxide treated sulfite pulps and the stabilization of active halogen against degradation by peroxides or peroxide residues are in pulp and paper processing, recycle pulping and papermaking, deinking, pulp bleaching, biomass bleaching, textile bleaching or clay slurry bleaching.
- Preferred aqueous systems are pulp and papermaking slurries and liquors, recycle pulp slurries, pulp thick stock, deinking pulp slurries, pulp or biomass bleaching slurries and liquids, textile bleaching liquids and clay slurries.
- Still other preferred applications are in aqueous systems found in food and crop protection applications, including fruit and vegetable washes, meat and poultry processing, beverage processing, fish farming, and aquaculture.
- the aqueous system containing peroxides is obtained by the addition of a composition comprising at least one peroxy compound to said aqueous system at a pH greater than 5
- aqueous system is selected from the group consisting of pulp and papermaking slurries, recycle pulp slurries, pulp thick stock, deinking pulp slurries, pulp or biomass bleaching slurries and liquids, textile bleaching solutions, and clay slurries.
- optimized cost performance can be achieved through the co-application of sulfite and peroxy compounds, optionally in combination with activators such as tetraacetylethylenediamine, co-application of peroxy compounds with active halogens, or co- application of sulfite and peroxy compounds followed by co-application or generation of peroxy compounds with active halogens.
- activators such as tetraacetylethylenediamine
- co-application of peroxy compounds with active halogens co-application of peroxy compounds with active halogens
- co-applications have been prohibited to date by the rapid mutual neutralization of these species.
- the current invention demonstrates methodologies for utilizing these classes of compounds cooperatively and even synergistically.
- Another object of the invention is an analytical method for determining peroxide concentrations in aqueous systems containing sulfite and/or bisulfite.
- the method comprises the steps of:
- the amount of unreacted N-hydrogen-stabilized active chlorine compound in step (ii) may be measured by any method known in the art, in particular by the well-known DPD method according to ISO 7393-2.
- the sulfite and/or bisulfite concentration corresponds to the difference of the amount of N-hydrogen-stabilized active chlorine compound added in step (i) and the amount of unreacted N-hydrogen-stabilized active chlorine compound measured in step (ii).
- step (iii) can be achieved by one of the methods known in the art, for example by titration with thiosulfate using potassium iodide as indicator.
- a preferred N-hydrogen-stabilized active chlorine compound to be used in the above analytical method is l-chloro-5,5-dimethylhydantoin (MCDMH).
- Ig cfu/mL denotes the common (decadic) logarithm of the number of colony- forming units per milliliter or, in connection with the term “reduction”, the common logarithm of the quotient of the number of colony-forming units per milliliter before treatment and the number of colony-forming units after treatment. Unless otherwise indicated all concentrations in percent or ppm are expressed on a weight basis.
- Aqueous solutions containing sodium sulfite and hydrogen peroxide were mixed at 21 °C to obtain a solution having a sulfite content (as SO 3 ) of 40 ppm, a hydrogen peroxide content of 20.0 ppm and a pH of 6.7.
- the temperature of the solution was maintained at 21 °C and the residual sulfite and peroxide content was determined at 15, 30 and 60 minutes after mixing.
- the procedure consisted of adding a known amount of l-chloro-5,5-dimethylhydantoin (MCDMH) to the samples in excess of the estimated residual sulfite content. The remaining MCDMH concentration was then measured by standard DPD total halogen methodologies.
- the H 2 O 2 concentration was determined by recording the concentration of H 2 O 2 measured using acidic thiosulfate titration with KI indicator (HACH HYP-I hydrogen peroxide test kit — Hach Co., Loveland, CO). Since this titration is run at acidic pH, this method yields the concentration of H 2 O 2 in excess of the sulfite concentration contained in the sample. As the sulfite concentration is known from the MCMDH analysis and Equation 1, the H 2 O 2 concentration can be calculated using the following Equation 2:
- the estimated error in the methodology is ⁇ 1 ppm
- Example 2 The procedure of Example 1 was repeated with the difference that the pH of the mixed solution was 9.0 and the residual concentrations were determined 5, 15, 30, 60, 120 and 1080 minutes after mixing. The results are shown in Table 2 which demonstrates that the co-stability of hydrogen peroxide and sulfite is even further enhanced at pH 9.0 where a significant residual concentration of both peroxide and sulfite was observed even after a period of 2 h. Table 2
- Synergistic biocidal performance upon co-application of sulfite with hydrogen peroxide at elevated pH was investigated.
- the sulfite and peroxide concentrations indicated in Table 3 below were added to an aqueous solution made from: (a) deionized water, (b) NaHCO 3 to achieve a carbonate buffer concentration of 200 ppm (as CaCO 3 total alkalinity), (c) sulfite bleached pulp slurry to achieve a final consistency of 0.05%, carrying an associated minimal concentration of residual sulfite of 6 ppm, and (d) NaOH to achieve a pH of 9.0.
- the microbial population was that provided by preparing the pulp slurry 24—48 h prior to testing and storing at room temperature, thus allowing microbial growth to a high test level.
- Populations reported are total aerobic counts using tryptone soy agar plating. The test results are shown in Table 3.
- the stability of nitrogen-bound active halogen species in the presence of residual H 2 O 2 was investigated. Free and total chlorine concentrations were measured by standard DPD methodology and the total H 2 O 2 concentration by acidic sulfite titration.
- the concentration of MCDMH is the concentration of the total active halogen less the concentration of free active halogen.
- the concentration of H 2 O 2 is the total oxidant concentration less the MCDMH concentration.
- the effect of the addition of a molar equivalent of 5,5-dimethylhydantoin (DMH) to NaOCl solutions prior to combination with hydrogen peroxide was investigated.
- the results are shown in Table 7.
- the concentration of MCDMH is the concentration of the total active halogen less the concentration of free active halogen.
- the concentration Of H 2 O 2 is the total oxidant concentration less the MCDMH concentration.
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Zoology (AREA)
- Wood Science & Technology (AREA)
- Environmental Sciences (AREA)
- Dentistry (AREA)
- Agronomy & Crop Science (AREA)
- Plant Pathology (AREA)
- Pest Control & Pesticides (AREA)
- Inorganic Chemistry (AREA)
- Analytical Chemistry (AREA)
- Physics & Mathematics (AREA)
- Water Supply & Treatment (AREA)
- Organic Chemistry (AREA)
- Hydrology & Water Resources (AREA)
- Pathology (AREA)
- Immunology (AREA)
- General Physics & Mathematics (AREA)
- Biochemistry (AREA)
- Environmental & Geological Engineering (AREA)
- Medicinal Chemistry (AREA)
- Food Science & Technology (AREA)
- Agricultural Chemicals And Associated Chemicals (AREA)
- Toxicology (AREA)
- Treatment Of Water By Oxidation Or Reduction (AREA)
- Paper (AREA)
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
- Apparatus For Disinfection Or Sterilisation (AREA)
Abstract
Disclosed is a method for controlling microbial growth in an aqueous system containing sulfite and/or bisulfite residues by addition of a peroxy compound at a pH of greater than 5. Also disclosed is a method for stabilizing an active halogen biocide in an aqueous system containing peroxide residues by addition of an N-hydrogen compound to the active halogen biocide before combining it with the peroxide containing aqueous system. Further disclosed is an optimized papermaking biocide program consisting of initially treating sulfite bleached pulp with peroxide followed by application of an N-hydrogen-stabilized active halogen compound to the paper producing white waters and an analytical method for determining peroxide concentrations in aqueous systems in the presence of sulfite and/or bisulfite.
Description
Synergistic Peroxide Based Biocidal Compositions
The invention relates to a method for controlling microbial growth in aqueous systems containing sulfite and/or bisulfite residues, such as solutions or suspensions obtained after appli- cation of sulfite-based reducing bleaches. It further relates to a method for stabilizing active halogen biocides in peroxide-containing aqueous systems.
Reducing bleaches are frequently used in paper making applications. Such bleaching processes typically employ bisulfite or bisulfite generating solutions. While enhancing paper brightness, the use of such solutions can also result in sulfite residues in the produced pulp. Sulfite residues make pulp preservation and subsequent paper machine deposit control more difficult as many major paper slimicides and preservatives such as dibromonitrilopropionamide, isothiazolinones, and, in particular, oxidizing biocides are unstable in the presence of sulfite.
Surprisingly, it has been found that at optimized pH, application of oxidizing biocides to systems containing residual sulfite can not only be successful but can even provide synergistic microbial control. Specifically, it has been found that upon optimization of pH sulfite bleached pulp can be effectively, even synergistically, treated with hydrogen peroxide for enhanced bleaching and microbial control.
The rapid neutralization of hydrogen peroxide by sulfite in acidic media (pH <5) is well known and is the basis of standard hydrogen peroxide titrimetric analytical methods. It has been found that at elevated pH these normally incompatible materials can coexist for time periods sufficient for bleaching and microbial control applications.
According to the invention, microbial growth in an aqueous system containing sulfite and/or bisulfite residues is controlled by adjusting and maintaining a pH >5, preferably pH 6-11, and more preferably 7.5-10, in the aqueous system and adding a peroxy compound. These pH ranges as well as any numerical ranges in this application which are defined by upper and lower boundaries are to be understood to also include all subranges resulting from the combination of any of the upper boundaries with any of the lower boundaries.
Preferred peroxy compounds include hydrogen peroxide, inorganic peroxy compounds such as alkali metal or alkaline earth metal perborates, percarbonates or persulfates, organic peroxy acids such as peracetic or perbenzoic acid, other organic peroxy compounds such as urea peroxide, and mixtures of the beforementioned. The term "persulfates" includes both mono- persulfates (i.e., the salts of peroxymonosulfuric acid, H2SO5) and peroxydisulfates (i.e., the salts of peroxydisulfuric acid, H2S2O8).
The efficacy of the peroxy compounds may be increased by the addition of bleach activators such as tetraacetylethylenediamine (TAED).
A particularly preferred peroxy compound is hydrogen peroxide.
The pH of the aqueous system can be controlled and/or buffered, if necessary, by addition of bases or basic salts such as alkali or alkaline earth metal hydroxides, carbonates, bicarbonates, borates, metasilicate, or mixtures thereof.
In a preferred embodiment the concentrations of sulfite and/or bisulfite and peroxy compound immediately after addition of the peroxy compound are 1 to 300 ppm each, more preferably 5 to 200 ppm and most preferred 10 to 100 ppm each.
Applications which may benefit from the sulfite/peroxide compatibilization according to the invention include pulp and papermaking, recycle paper pulping and papermaking, pulp or bio- mass bleaching, textile bleaching, and similar applications.
As treating aqueous systems such as pulp slurries with peroxy compounds such as hydrogen peroxide will result in a range of peroxide concentrations or residues in said aqueous systems it is important that any subsequently applied biocides be stable to the peroxide treatment or peroxide residues. It has been found that solutions containing hydrogen peroxide, such as diluted pulps for papermaking, can be successfully treated with stabilized active halogen. This additional result is unexpected as it is well known that active halogen species are neutralized by the presence of peroxides since hydrogen peroxide can act as both an oxidizing and a reducing agent.
Specifically it has been found that active halogen species with nitrogen-bound halogen are surprisingly stable in the presence of peroxides. According to the invention, an active halogen bio- cide in an aqueous system containing peroxides or peroxide residues is stabilized by adding an N-hydrogen compound to the active halogen biocide before combining the biocide with the peroxide containing aqueous system. Here and herein below, an N-hydrogen compound is an organic or inorganic compound having at least one hydrogen atom directly bound to a nitrogen atom.
Application areas where both peroxides and active halogen have found utility are those most suited to this novel approach.
Active halogen biocides are biocides containing halogen, in particular chlorine or bromine, in the oxidation state 0 or +1, such as elemental chlorine or bromine and hypochlorite or hypo- bromite.
In a preferred embodiment the concentration of active halogen (as Cl2) stabilized by an N-hy- drogen compound is 0.1 to 20 ppm. Here and herein below, the expression "as Cl2" denotes the concentration of elemental chlorine that is stoichiometrically equivalent to the concentration of active halogen in a given system.
Preferred N-hydrogen compounds are selected from the group consisting of ammonia, ammonium salts, such as ammonium sulfate and ammonium bromide, other nitrogen compounds containing no carbon-hydrogen bonds, such as urea, biuret, isocyanuric acid, and sulfamic acid, organic N-hydrogen compounds such as p-toluenesulfonamide, 5,5-dialkyl- hydantoins, methanesulfonamide, barbituric acid, 5-methyluracil, imidazoline, pyrrolidone, morpholine, acetanilide, acetamide, N-ethylacetamide, phthalimide, benzamide, succinimide, N-methylolurea, iV-methylurea, acetylurea, methyl allophanate, methyl carbamate, phthalo- hydrazide, pyrrole, indole, formamide, N-methylformamide, dicyanodiamide, ethyl carbamate, 1,3-dimethylbiuret, methylphenylbiuret, 4,4-dimethyl-2-oxazolidinone, 6-methyluracil, 2-imidazolidinone, ethyleneurea, 2-pyrimidone, azetidin-2-one, 2-pyrrolidone, caprolactam, phenylsulfinimide, phenylsulfinimidylamide, diaryl- or dialkylsulfinimides, isothiazoline- 1,1 -dioxide, hydantoin, glycine, piperidine, piperazine, ethanolamine, glycinamide, creatine, and glycoluril.
More preferably the Ν-hydrogen compound is 5,5-dimethylhydantoin, urea, ammonia, or an ammonium salt.
The peroxide or peroxide residue in the aqueous system is preferably hydrogen peroxide, an alkali metal or alkaline earth metal percarbonate, perborate, or persulfate, an organic peroxy acid, or a mixture of two or more of the beforementioned, hydrogen peroxide being most preferred.
Preferred applications of either finding, namely the synergistic performance of peroxide treated sulfite pulps and the stabilization of active halogen against degradation by peroxides or peroxide residues, are in pulp and paper processing, recycle pulping and papermaking, deinking, pulp bleaching, biomass bleaching, textile bleaching or clay slurry bleaching. Preferred aqueous systems are pulp and papermaking slurries and liquors, recycle pulp slurries, pulp thick stock, deinking pulp slurries, pulp or biomass bleaching slurries and liquids, textile bleaching liquids and clay slurries.
- A -
Other preferred applications are in water treatment such as waste water, papermaking liquors and waters, pool and spa waters, industrial cooling waters, waters exposed to reverse osmosis filters or ion exchange resins, and aqueous systems in oil field applications, including fractionation tanks and down hole applications, or hard surface disinfection.
Still other preferred applications are in aqueous systems found in food and crop protection applications, including fruit and vegetable washes, meat and poultry processing, beverage processing, fish farming, and aquaculture.
Combining the two findings, namely the synergistic performance of peroxide treated sulfite pulps and the stabilization of active halogen against degradation by hydrogen peroxide or peroxide residues leads to the definition of a highly cost-effective microbial control program for papermaking. This program comprises pulp bleaching with sulfite followed by peroxide treatment and subsequent conversion of the pulp into paper in the presence of an active halogen biocide with nitrogen-bound halogen.
In a preferred embodiment, the aqueous system containing peroxides is obtained by the addition of a composition comprising at least one peroxy compound to said aqueous system at a pH greater than 5
Preferred applications of the combined methods are those wherein the aqueous system is selected from the group consisting of pulp and papermaking slurries, recycle pulp slurries, pulp thick stock, deinking pulp slurries, pulp or biomass bleaching slurries and liquids, textile bleaching solutions, and clay slurries.
According to the invention, optimized cost performance can be achieved through the co-application of sulfite and peroxy compounds, optionally in combination with activators such as tetraacetylethylenediamine, co-application of peroxy compounds with active halogens, or co- application of sulfite and peroxy compounds followed by co-application or generation of peroxy compounds with active halogens. Such co-applications have been prohibited to date by the rapid mutual neutralization of these species. The current invention demonstrates methodologies for utilizing these classes of compounds cooperatively and even synergistically.
Another object of the invention is an analytical method for determining peroxide concentrations in aqueous systems containing sulfite and/or bisulfite. The method comprises the steps of:
(i) adding a defined excess of an N-hydrogen-stabilized active chlorine compound to immediately destroy the sulfite and/or bisulfite while leaving an amount of unreacted N-hydrogen stabilized active chlorine compound,
(ii) measuring the amount of unreacted N-hydrogen-stabilized active chlorine compound to determine the sulfite and/or bisulfite concentration, and (iii) determining the peroxide concentration.
The amount of unreacted N-hydrogen-stabilized active chlorine compound in step (ii) may be measured by any method known in the art, in particular by the well-known DPD method according to ISO 7393-2. The sulfite and/or bisulfite concentration corresponds to the difference of the amount of N-hydrogen-stabilized active chlorine compound added in step (i) and the amount of unreacted N-hydrogen-stabilized active chlorine compound measured in step (ii).
The determination of the peroxide concentration in step (iii) can be achieved by one of the methods known in the art, for example by titration with thiosulfate using potassium iodide as indicator.
A preferred N-hydrogen-stabilized active chlorine compound to be used in the above analytical method is l-chloro-5,5-dimethylhydantoin (MCDMH).
The following non-limiting examples are intended to illustrate the invention in more detail.
Examples
The expression "Ig cfu/mL" denotes the common (decadic) logarithm of the number of colony- forming units per milliliter or, in connection with the term "reduction", the common logarithm of the quotient of the number of colony-forming units per milliliter before treatment and the number of colony-forming units after treatment. Unless otherwise indicated all concentrations in percent or ppm are expressed on a weight basis.
Example 1
Aqueous solutions containing sodium sulfite and hydrogen peroxide were mixed at 21 °C to obtain a solution having a sulfite content (as SO3 ) of 40 ppm, a hydrogen peroxide content of 20.0 ppm and a pH of 6.7. The temperature of the solution was maintained at 21 °C and the residual sulfite and peroxide content was determined at 15, 30 and 60 minutes after mixing. The procedure consisted of adding a known amount of l-chloro-5,5-dimethylhydantoin (MCDMH) to the samples in excess of the estimated residual sulfite content. The remaining MCDMH concentration was then measured by standard DPD total halogen methodologies. As sulfite rapidly neutralizes MCDMH at all pHs the sulfite concentration is the concentration of MCDMH added less the concentration of MCDMH measured, see Equation 1 below. This procedure is valid in
the presence of H2O2 as H2O2 does not react with MCMDH and does not interfere with the total active halogen method as it is run at approximately neutral pH.
( 1 ) [Sulfite] = [MCDMHadded] - [MCDMHmeasured]
The H2O2 concentration was determined by recording the concentration of H2O2 measured using acidic thiosulfate titration with KI indicator (HACH HYP-I hydrogen peroxide test kit — Hach Co., Loveland, CO). Since this titration is run at acidic pH, this method yields the concentration of H2O2 in excess of the sulfite concentration contained in the sample. As the sulfite concentration is known from the MCMDH analysis and Equation 1, the H2O2 concentration can be calculated using the following Equation 2:
(2) [H2O2] = [H2O2 measured] + [Sulfite«Uculated]
The estimated error in the methodology is ±1 ppm
The results are shown in Table 1 which reveals that a significant residual concentration of both materials is observed even after a period of 30 minutes.
Table 1
Example 2
The procedure of Example 1 was repeated with the difference that the pH of the mixed solution was 9.0 and the residual concentrations were determined 5, 15, 30, 60, 120 and 1080 minutes after mixing. The results are shown in Table 2 which demonstrates that the co-stability of hydrogen peroxide and sulfite is even further enhanced at pH 9.0 where a significant residual concentration of both peroxide and sulfite was observed even after a period of 2 h.
Table 2
Example 3
Synergistic biocidal performance upon co-application of sulfite with hydrogen peroxide at elevated pH was investigated. The sulfite and peroxide concentrations indicated in Table 3 below were added to an aqueous solution made from: (a) deionized water, (b) NaHCO3 to achieve a carbonate buffer concentration of 200 ppm (as CaCO3 total alkalinity), (c) sulfite bleached pulp slurry to achieve a final consistency of 0.05%, carrying an associated minimal concentration of residual sulfite of 6 ppm, and (d) NaOH to achieve a pH of 9.0.
The microbial population was that provided by preparing the pulp slurry 24—48 h prior to testing and storing at room temperature, thus allowing microbial growth to a high test level. The untreated control populations were Ig cfu/mL = 5.9 for the 3 h contact test and Ig cfu/mL = 6.5 for the 24 h contact test. Populations reported are total aerobic counts using tryptone soy agar plating. The test results are shown in Table 3.
Table 3
It appears that the presence of sulfite alone had no significant effect on bacterial populations at 32-128 ppm sulfite concentrations. Hydrogen peroxide in contrast demonstrated a slowly developing level of biocidal efficacy yielding Ig cfu/mL reductions of 1.2-3.5 in 3 h and 5.5 in 24 h. Surprisingly, at 3 h contact some mixed sulfite/hydrogen peroxide systems (Test Nos. 7 and 9) provided greater efficacy than hydrogen peroxide alone (Test No. 5).
The observed level of performance demonstrates a clear synergistic effect of sulfite and peroxide at elevated peroxide concentrations. As sulfite alone has no biocidal efficacy, the ob- served enhanced efficacy of hydrogen peroxide in the presence of sulfite is a result of synergy. This result can be quantified using the method of KuIl et al. (F. C. KuIl, P. C. Elisman, H. D. Sylwestrowicz and P. K. Mayer, Appl. Microbiol, 1961, 9, 538) which specifies that synergy is demonstrated when a synergy index (SI) according to Equation 3 of less than 1.0 is observed.
(3) SI = (level of A)/(efficacious level of A) + (level of B)/(efficacious level of B)
Setting A as the sulfite concentration and B as the peroxide concentration the following result is achieved: As sulfite is essentially non-biocidal the denominator of the first term becomes infinite and the value of the first term zero. If we set the efficacy level as the level that produces a Ig cfu/mL reduction of 3.5 in 3 h, the denominator of the second term becomes 160 ppm (according to Test No. 5, Table 3). Synergy indices of less than 1.0 are thus achieved for Test Nos. 7 and 9 at 3 h contact according to Equation 4 below, as these tests produced greater than the target Ig cfu/mL reduction of 3.5 associated with 160 ppm of hydrogen peroxide alone.
(4) SI = 0 + (<160)/160 = (<1.0)
Example 4
Synergy upon co-application of sulfite with hydrogen peroxide at higher concentrations of sulfite and hydrogen peroxide was investigated. The conditions were the same as in Example 3. The microbial population of the untreated control was Ig cfu/mL = 6.26 for the 3 h contact test and Ig cfu/mL = 6.18 for the 24 h contact test. The results are shown in Table 4.
Table 4
As shown in Table 4, the application of sulfite at concentrations of 128-512 ppm has no significant effect on the microbial populations. Hydrogen peroxide at concentrations of 120-160 ppm in contrast demonstrates a slowly developing level of biocidal efficacy yielding Ig cfu/mL reductions of 3.3-4.0 in 3 h and 3.7-5.5 in 24 h. Again surprisingly some mixed sulfite/hydrogen peroxide systems provided greater efficacy than hydrogen peroxide alone. The observed level of performance demonstrates a clear synergistic effect of sulfite and peroxide at elevated peroxide concentrations. As sulfite by itself exhibits no biocidal efficacy the observation of enhanced efficacy of hydrogen peroxide in the presence of sulfite is result of synergy. A completely rigorous demonstration of synergy is possible for Test No. 9. If the desired effect is set as Ig cfu/mL reduction of 4.2 we can see that >512 ppm sulfite would be required to achieve this. The amount of hydrogen peroxide alone that it would take to achieve this is 150 ppm or greater. This produces Equation 5:
(5) SI = 32/(>512) + (<120)/150 = (<0.063) + (<0.8) = (<0.86)
Example 5
The bactericidal efficacy of solutions containing sulfite and hydrogen peroxide was further investigated in the absence of pulp. Efficacy was measured against Pseudomonas aeruginosa grown in nutrient in the presence of 83 and 830 ppm sulfite. The sulfite-containing P. aeruginosa inoculum was then diluted 1 :99 with Butterfield's buffer at pH 7.0. The sulfite concentrations in Table 5 below are the those in the final dilution. The dilutions were then contacted with 50 ppm hydrogen peroxide for 3 h at 37 °C. The untreated control populations (Test 1) were Ig cfu/mL = 6.0. The test results are shown in Table 5.
Table 5
As shown in Table 5, the biocidal efficacy of hydrogen peroxide against P. aeruginosa grown up in 830 ppm sulfite diluted to 8.3 ppm during application (Ig cfu/mL reduction of 1.5) was surprisingly greater than that observed against P. aeruginosa grown up in the absence of sulfite (Ig cfu/mL reduction of 0.9). Thus, the surprising enhancement of hydrogen peroxide bactericidal efficacy by the addition of sulfite was further exemplified in the absence of pulp.
Example 6
The stability of nitrogen-bound active halogen species in the presence of residual H2O2 was investigated. Free and total chlorine concentrations were measured by standard DPD methodology and the total H2O2 concentration by acidic sulfite titration. The concentration of MCDMH is the concentration of the total active halogen less the concentration of free active halogen. The concentration of H2O2 is the total oxidant concentration less the MCDMH concentration. Combination of 2.1 ppm (0.062 mM) H2O2 with 1 ppm (0.014 mM) NaOCl (as Cl2) resulted in an
immediate stoichiometric decrease in both materials, leaving a H2O2 residue of -1.6 ppm (0.048 mM) with no detectable free chlorine. The indicated reaction is shown in Equation 6.
(6) NaOCl + H2O2 → H2O +NaCl + O2
The inherent instability of active halogen in the presence OfH2O2 is shown in Table 6.
Table 6
1) - Determined using HACH HYP-I hydrogen peroxide test kit (Hach Co., Loveland, CO)
Example 7
The effect of the addition of a molar equivalent of 5,5-dimethylhydantoin (DMH) to NaOCl solutions prior to combination with hydrogen peroxide was investigated. The results are shown in Table 7. The concentration of MCDMH is the concentration of the total active halogen less the concentration of free active halogen. The concentration Of H2O2 is the total oxidant concentration less the MCDMH concentration.
Table 7
1) - Determined using HACH HYP-I hydrogen peroxide test kit (Hach Co., Loveland, CO)
It appears that the addition of DMH stabilizes both active chlorine and hydrogen peroxide upon combination. No significant decomposition was observed even after 1 h contact time.
Claims
1. A method for controlling microbial growth in an aqueous system containing sulfite and/or bisulfite residues, said method comprising the addition of a composition comprising at least one peroxy compound to said aqueous system at a pH greater than 5.
2. The method of claim 1, wherein the peroxy compound is selected from the group consisting of hydrogen peroxide, alkali metal percarbonates, alkaline earth metal percarbo- nates, alkali metal perborates, alkaline earth metal perborates, alkali metal persulfates, alkaline earth metal persulfates, organic peroxy acids, and mixtures thereof.
3. The method of claim 2 where the peroxy compound is hydrogen peroxide.
4. The method of any of claims 1 to 3, wherein said composition further comprises a bleach activator.
5. The method of claim 4, wherein said bleach activator is tetraacetylethylendiamine.
6. The method of any of claims 1 to 5, wherein the pH is between 6 and 11.
7. The method of claim 6, wherein the pH is between 7.5 and 10.
8. The method of any of claims 1 to 7, wherein the pH of the aqueous system is adjusted using a compound selected from the group consisting of alkali metal hydroxides, alkaline earth metal hydroxides, alkali metal bicarbonates, alkaline earth metal bicarbonates, alkali metal carbonates, alkaline earth metal carbonates, alkali metal metasilicates, or mixtures thereof.
9. The method of any of claims 1 to 8, wherein the concentrations of sulfite and/or bisulfite and peroxy compound immediately after addition are 1 to 300 ppm each.
10. A method for stabilizing an active halogen biocide in a peroxide-containing aqueous system, said method comprising the addition of an N-hydrogen compound to the active halogen biocide before combining it with said peroxide-containing aqueous system.
11. The method of claim 10, wherein the concentration of active halogen stabilized by N-hydrogen compound (as Cl2) is 0.1 to 20 ppm.
12. The method of claim 10 or 1 1, wherein the N-hydrogen compound is selected from the group consisting of ammonia, ammonium salts, such as ammonium sulfate and ammonium bromide, nitrogen compounds containing no carbon-hydrogen bonds, such as urea, biuret, sulfamic acid, and isocyanuric acid, substituted N-hydrogen compounds such as methanesulfonamide,/?-toluenesulfonamide, 5,5-dialkylhydantoins, barbituric acid,
5-methyluracil, imidazoline, pyrrolidone, morpholine, acetanilide, acetamide, N-ethyl- acetamide, phthalimide, benzamide, succinimide, iV-methylolurea, iV-methylurea, acetyl- urea, methyl allophanate, methyl carbamate, phthalohydrazide, pyrrole, indole, form- amide, Λf-methylformamide, dicyanodiamide, ethyl carbamate, 1,3-dimethylbiuret, methylphenylbiuret, 4,4-dimethyl-2-oxazolidinone, 6-methyluracil, 2-imidazolidinone, ethyleneurea, 2-pyrimidone, azetidin-2-one, 2-pyrrolidone, caprolactam, phenylsulfin- imide, phenylsulfinimidylamide, diarylsulfinimides, dialkylsulfinimides, isothiazoline- 1,1 -dioxide, hydantoin, glycine, piperidine, piperazine, ethanolamine, glycinamide, creatine, glycoluril, and mixtures thereof.
13. The method of claim 12, wherein the N-hydrogen compound is 5,5-dimethylhydantoin.
14. The method of claim 12, wherein the N-hydrogen compound is urea, ammonia, or an ammonium salt.
15. The method of any of claims 10 to 14, wherein the peroxide is selected from the group consisting of hydrogen peroxide, alkali metal percarbonates, alkaline earth metal percarbonates, alkali metal perborates, alkaline earth metal perborates, alkali metal persulfates, alkaline earth metal persulfates, organic peroxy acids, and mixtures thereof.
16. The method of claim 15, wherein the peroxide is hydrogen peroxide.
17. The method of any of claims 10 to 16, wherein the aqueous system is selected from the group consisting of pulp and papermaking slurries, recycle pulp slurries, pulp thick stock, deinking pulp slurries, pulp or biomass bleaching slurries and liquids, textile bleaching solutions and clay slurries.
18. The method of any of claims 10 to 16, wherein the aqueous system is selected from the group consisting of waste water, papermaking liquors and waters, pool and spa waters, industrial cooling waters, waters exposed to reverse osmosis filters or ion exchange resins, and aqueous systems in oil field applications, including fractionation tanks and down hole applications.
19. The method of any of claims 10 to 16, wherein the aqueous system is selected from aqueous solutions for food and crop protection applications, including fruit and vegetable washes, meat and poultry processing, beverage processing, fish farming and aquaculture.
20. The method of any of claims 10 to 19, wherein the aqueous system containing peroxides has been obtained by the method of any of claims 1 to 9.
21. A method for determining peroxide concentrations in aqueous systems in the presence of sulfite and/or bisulfite, said method comprising the steps of (i) adding a defined excess of an N-hydrogen-stabilized active chlorine compound to immediately destroy the sulfite and/or bisulfite while leaving an amount of unreacted
N-hydrogen stabilized active chlorine compound,
(ii) measuring the amount of unreacted N-hydrogen-stabilized active chlorine compound to determine the sulfite and/or bisulfite concentration, and (iii) determining the peroxide concentration.
22. The method of claim 21, wherein the N-hydrogen stabilized active chlorine compound is 1 -chloro-5,5-dimethylhydantoin.
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP09778746A EP2346337A2 (en) | 2008-09-26 | 2009-09-28 | Synergistic peroxide based biocidal compositions |
CN2009801382852A CN102176830A (en) | 2008-09-26 | 2009-09-28 | Synergistic peroxide based biocidal compositions |
JP2011528251A JP5670334B2 (en) | 2008-09-26 | 2009-09-28 | Synergistic peroxide disinfectant composition |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10032608P | 2008-09-26 | 2008-09-26 | |
US61/100,326 | 2008-09-26 | ||
EP08018736.2 | 2008-10-27 | ||
EP08018736 | 2008-10-27 |
Publications (3)
Publication Number | Publication Date |
---|---|
WO2010034519A2 true WO2010034519A2 (en) | 2010-04-01 |
WO2010034519A3 WO2010034519A3 (en) | 2011-04-28 |
WO2010034519A8 WO2010034519A8 (en) | 2011-06-23 |
Family
ID=44246644
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP2009/006975 WO2010034519A2 (en) | 2008-09-26 | 2009-09-28 | Synergistic peroxide based biocidal compositions |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP2346337A2 (en) |
JP (2) | JP5670334B2 (en) |
CN (2) | CN102176830A (en) |
WO (1) | WO2010034519A2 (en) |
Families Citing this family (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103053613A (en) * | 2011-10-21 | 2013-04-24 | 纳尔科公司 | Improved biological control by using chlorine-stabilizing agent mixture |
CN109769855A (en) * | 2011-10-21 | 2019-05-21 | 纳尔科公司 | Sulfamic acid or its salt, the application of combination or other halogen-containing biocides with ammonium salt and/or amine in field of papermaking |
US9909219B2 (en) * | 2014-04-14 | 2018-03-06 | Ecolab Usa Inc. | Slurry biocide |
WO2016080243A1 (en) * | 2014-11-17 | 2016-05-26 | 日本曹達株式会社 | Method for treating water for indoor swimming pool |
KR101784513B1 (en) | 2017-03-30 | 2017-10-11 | 허운덕 | Herbicide compositions for controlling pests of horticultural products comprising rare-earth elements as active ingredients and method for manufacturing the same |
KR101915411B1 (en) | 2017-09-26 | 2018-11-05 | 허운덕 | Herbicide compositions for controlling pests of horticultural products comprising rare-earth elements as active ingredients |
GB2592911B (en) * | 2020-02-28 | 2023-06-28 | Aga Nanotech Ltd | A plasma-activatable wound dressing for treatment of infections |
CN114680348B (en) * | 2020-12-31 | 2023-11-03 | 广东美的白色家电技术创新中心有限公司 | Cleaning device |
CN115474609B (en) * | 2021-06-16 | 2024-01-26 | 苏州北辰新材料科技有限公司 | Disinfectant, preparation method thereof and film layer |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3684477A (en) * | 1969-08-28 | 1972-08-15 | Fmc Corp | Microorganism control |
US5234606A (en) * | 1991-10-09 | 1993-08-10 | Nec Environment Engineering Ltd. | Method and system for recovering wastewater |
EP0622339A1 (en) * | 1993-04-30 | 1994-11-02 | Kodak-Pathe | Process for treating photographic effluents by means of ultraviolet radiation and hydrogen peroxide |
WO1996011882A1 (en) * | 1994-10-14 | 1996-04-25 | Lonza Inc. | Hydantoin-enhanced halogen efficacy in pulp and paper applications |
WO2003062149A2 (en) * | 2002-01-22 | 2003-07-31 | Lonza Inc. | Antimicrobial composition including a triamine and a biocide |
WO2007011445A2 (en) * | 2005-07-15 | 2007-01-25 | Nalco Company | Synergistic composition and method for inhibiting growth of microorganisms |
WO2008056025A2 (en) * | 2006-11-09 | 2008-05-15 | Kemira Oyj | Method for preventing growth of microorganisms, and a combination for the prevention of microbial growth |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5631492A (en) * | 1979-08-22 | 1981-03-30 | Nitto Chem Ind Co Ltd | Stabilization of residual chlorine |
JPH04360672A (en) * | 1991-06-07 | 1992-12-14 | Juichiro Yagi | Bacteria-elimination and bactericidal agent for food |
JP3560360B2 (en) * | 1994-05-11 | 2004-09-02 | 伯東株式会社 | Sterilization treatment method in water system |
FR2728143A1 (en) * | 1994-12-16 | 1996-06-21 | Sodifra | AQUEOUS COMPOSITION BASED ON H2O2, ACIDS AND AG, PROCESS FOR PREPARATION AND USE IN THE FIELD OF DISINFECTION AND / OR HYGIENE |
JP3219698B2 (en) * | 1996-09-06 | 2001-10-15 | クリーンケミカル株式会社 | Manufacturing method of disinfectant solution |
EP1027827A1 (en) * | 1998-05-28 | 2000-08-16 | Mandalay Inversiones, S.L. | Disinfectant composition |
JP4321733B2 (en) * | 2000-03-23 | 2009-08-26 | 伯東株式会社 | Stable water treatment composition containing hypochlorite |
BR0211313A (en) * | 2001-06-29 | 2004-09-28 | Lonza Ag | Halogen-containing biocide mixtures, halogen stabilizers and nitrogen-containing biocides |
ATE534295T1 (en) * | 2002-09-11 | 2011-12-15 | Univ Louisiana State | BIOCIDAL COMPOSITION AND SIMILAR METHODS |
-
2009
- 2009-09-28 WO PCT/EP2009/006975 patent/WO2010034519A2/en active Application Filing
- 2009-09-28 JP JP2011528251A patent/JP5670334B2/en active Active
- 2009-09-28 CN CN2009801382852A patent/CN102176830A/en active Pending
- 2009-09-28 CN CN201610631117.9A patent/CN106417360A/en active Pending
- 2009-09-28 EP EP09778746A patent/EP2346337A2/en not_active Withdrawn
-
2014
- 2014-07-07 JP JP2014140015A patent/JP2015028015A/en active Pending
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3684477A (en) * | 1969-08-28 | 1972-08-15 | Fmc Corp | Microorganism control |
US5234606A (en) * | 1991-10-09 | 1993-08-10 | Nec Environment Engineering Ltd. | Method and system for recovering wastewater |
EP0622339A1 (en) * | 1993-04-30 | 1994-11-02 | Kodak-Pathe | Process for treating photographic effluents by means of ultraviolet radiation and hydrogen peroxide |
WO1996011882A1 (en) * | 1994-10-14 | 1996-04-25 | Lonza Inc. | Hydantoin-enhanced halogen efficacy in pulp and paper applications |
WO2003062149A2 (en) * | 2002-01-22 | 2003-07-31 | Lonza Inc. | Antimicrobial composition including a triamine and a biocide |
WO2007011445A2 (en) * | 2005-07-15 | 2007-01-25 | Nalco Company | Synergistic composition and method for inhibiting growth of microorganisms |
WO2008056025A2 (en) * | 2006-11-09 | 2008-05-15 | Kemira Oyj | Method for preventing growth of microorganisms, and a combination for the prevention of microbial growth |
Non-Patent Citations (2)
Title |
---|
LIU W ET AL: "Optimal methods for quenching H2O2 residuals prior to UFC testing", WATER RESEARCH, ELSEVIER, AMSTERDAM, NL, vol. 37, no. 15, 1 September 2003 (2003-09-01), pages 3697-3703, XP004437626, ISSN: 0043-1354, DOI: DOI:10.1016/S0043-1354(03)00264-1 * |
N. J. RAGAB-DEPRE: "Water disinfection with the hydrogen peroxide-ascorbic acid-copper (II) system", APPLIED ENVIRONMENTAL MICROBIOLOGY, vol. 44, no. 3, September 1982 (1982-09), pages 555-560, XP002624438, * |
Also Published As
Publication number | Publication date |
---|---|
JP5670334B2 (en) | 2015-02-18 |
JP2012503614A (en) | 2012-02-09 |
WO2010034519A8 (en) | 2011-06-23 |
JP2015028015A (en) | 2015-02-12 |
WO2010034519A3 (en) | 2011-04-28 |
CN102176830A (en) | 2011-09-07 |
EP2346337A2 (en) | 2011-07-27 |
CN106417360A (en) | 2017-02-22 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20120237611A1 (en) | Synergistic peroxide based biocidal compositions | |
EP2346337A2 (en) | Synergistic peroxide based biocidal compositions | |
KR101307064B1 (en) | Synergistic composition amd method for inhibiting growth of microorganisms | |
AU692323B2 (en) | Hydantoin-enhanced halogen efficacy in pulp and paper applications | |
CA2640452A1 (en) | Suppressing microbial growth in pulp and paper | |
AU2010278367B2 (en) | Stabilized active halogen solutions | |
JP5985511B2 (en) | Use of oxidants to control microorganisms under reducing conditions | |
CA2844833C (en) | Improved biocontrol through the use of chlorine-stabilizer blends | |
US9161543B2 (en) | Biocontrol through the use of chlorine-stabilizer blends | |
CA2843162C (en) | Use of sulfamic acid or its salts as stabilizers for halogen containing biocides | |
US20070032397A1 (en) | Fragrant monopersulfate compositions for water treatment and articles containing them | |
US20120207852A1 (en) | Biocide compositions and related methods | |
NZ620230B2 (en) | Use of sulfamic acid or its salts as stabilizers especially in combination with ammonium salt and/or ammine for bleach or other halogen containing biocides in the paper area |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 200980138285.2 Country of ref document: CN |
|
NENP | Non-entry into the national phase in: |
Ref country code: DE |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2011528251 Country of ref document: JP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2009778746 Country of ref document: EP |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 09778746 Country of ref document: EP Kind code of ref document: A2 |