NZ296363A

NZ296363A - Synergistic biocidal compositions containing an oxidant and a non-oxidizing microbiocide for controlling bacteria

Info

Publication number: NZ296363A
Application number: NZ296363A
Authority: NZ
Inventors: Robert M Gerhold; Paul U Labine; Chih M Hwa; Grace L Fan
Original assignee: Betzdearborn Inc
Priority date: 1994-11-04
Filing date: 1995-10-31
Publication date: 1999-04-29
Also published as: EP0789595A1; WO1996014092A1; AU696309B2; AU4014795A; JPH10509141A; KR970706850A; MX9703280A; EP0789595A4; CA2204279A1; NO972002L; FI971852A; BR9509598A; NO972002D0; CZ135497A3; FI971852A0

Description

<div class="application article clearfix" id="description"> New Zealand Paient Spedficaiion for Paient Number £96363 New Zealand No 296363 International No PCT/US95/13947 TO BE ENTERED AFTER ACCEPTANCE AND PUBLICATION Priority dates 04 11 1994, Complete Specification Filed 31 101995 Classification (6) A01N35/00, A01N37/00.02, A01N43/80, A01 N59/00,02,08,10,12,14, A61L2/00,16,18 Publication date 29 April 1999 Journal No 1439 Title of Invention Synergistic biocidal combinations Name, address and nationality of apphcant(s) as in international application form BETZDEARBORN INC , 4636 Somerton Road, Trevose, Pennsylvania 19053, United States of America NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION 296363 WO 96/14092 ^ 3 U J U J PCTYUS95/13947 SYNERGISTIC BIOCIDAL COMBINATIONS 10 FIELD OF THE INVENTION The present invention relates to microbiccidal compositions and to processes of utilising these microbiocidal compositions for inhibiting the growth of microorganisms m aqueous systems. More particularly, the microbiocidal compositions of this inventJ on comprise a combination of (i) an oxidant, and (n) a non-oxidizing microbiocide optionally with a surfactant/dispersant, an anti-corrosive material, and/or an anti-scale material. BACKGROUND OF THE INVENTION The proliferation of microorganisms and resultant formation of slime is a problem which commonly occurs m many aqueous systems. Problematic slime producing 15 microorganisms include bacteria, airborne microorganisms, sulfate reducing bacteria, fungi and algae. Slime deposits commonly form m many industrial aqueous systems including cooling water systems, pulp and paper mill systems, petroleum operations, industrial lubricants, 20 cutting fluids, coolants, etc. The formation of slime by microorga sms in these systems is a significant and constant problem. For example, slime deposits deteriorate cooling toners made of wood and promote corrosion when deposited 25 on the metal surfaces of cooling water systems. Furthermore, slime deposits tend to plug or foul pipes and valves and reduce heat exchange or cooling efficiency on heat exchange surfaces. Pulp and paper mill systems operate under conditions 3 0 which encourage the growth of microorgamsr and often results in fouling problems. Moreover, microorganisms can form large slime deposits which can become dislodged and show up in the paper product as spots, holes or tears. This necessitates shutting down the paper making WO 96/14092 PCT/US95/13947 2 process to clean the equipment, and results m lost production time. Slims may also be objectionable from the standpoint of cleanliness and sanitation m breweries, wineries, 5 dairies and other industrial food and beverage process water systems. Moreover, sulfate reducing bacteria are often problematic in waters used for the secondary recovery of petroleum or for oil drilling in general. For example, these organisms reduce sulfates present in 10 the infection water to form insoluble iron sulfide deposits and may enhance corrosion of metals by accelerating galvanic action. The proliferation of bacteriological contamination m lubricants and cutting fluids is a common problem due 15 to the elevated temperature and unsanitary conditions found in many metal working plants. It is often necessary to discard these fluids due to microbiological contamination. Accordingly, because of the foregoing problems in 20 various industrial processes, numerous biocidal materials have been employed to eliminate, inhibit or to reduce microbial growth. Various oxidizing biocides have enjoyed widespread use m such applications including chlorine, chlorine dioxide and bromine. However, these 25 oxidizing biocides are not always effective for controlling microbiological growth. For example, oxidizing biocides are consumed by inorganic species such as ferrous iron, reduced manganese, sulfides, etc. as well as organic compounds which are commonly found in 30 those systems. In addition, the effectiveness of a biocide is rapidly reduced as a result of exposure to adverse physical conditions such as temperature or contact with i incompatible water treating agents in the system. 3 Therefore multiple doses or large quantities of expensive biocidal chemicals have heretofore been required m order to maintain control over microbial growth. SUMMARY OF THE INVENTION 5 It is an object of the present invention to provide novel microbiocidal compositions which provide enhanced effectiveness for controlling or inhibiting the growth of microorganisms in ar. aqueous system. It is another object of this invention to provide an 10 improved process for controlling microorganisms m aqueous systems such as pulp and paper mill systems, cooling water systems, metal working fluids and petroleum operations. It is another object of this invention to reduce the 15 level of toxic biocides in industrial-water effluents. It is an advantage of the present invention that the biocidal compositions permit a reduction in the dosage amount of biocide required to treat nuisance microbiota in industrial waters, and significantly reduces the time 20 required to control microbiological organisms. In accordance with the present invention, there have been provided certain novel biocidal compositions which are used to control or inhibit microbial growth, comprising (l) a microbiocidal effective amount of an 25 oxidant or oxidizing biocide, for inhibiting the growth of microorganisms, selected from the group consisting of monopersulfates, halogens, halogen releasing compounds, perborates, peroxides, percarbonates, perorganic acid, chlorine dioxide, persulfates, diperoxydodecanoic acid, permanganates, ozone and mixtures thereof, and (n) a microbiocidal effective amount of a non-oxidizing microbiocide selected from the group consisting of glutaraldehyde, limonene, bis(trichloromethyl) sulfone, 2-(decylthio)-ethanamine, dodecylguanidine hydrochloride, 2-(2-bromo-2-nitroethyl)1 30 intellectual property office OFNZ 25 FEB 1999 RECEIVED 4 (followed by page 4a) furan, poly(oxyethylene (dimethyliminio) ethylene (dimethyliminio) ethylene dichlorxde), alkyl dimethyl benzyl ammonium chloride, alkylamidopropyl propylene glycol dimethyl ammonium chloride phosphate, 2,4,4'-5 tnchloro-2'-hydroxydiphenyl ether, tetrakis- hydroxylmethyl phosphonium sulfate, tributyltetradecyl phosphonium chloride, 2-bromo-2-nitropropane-l, 3~diol, and 2,2-dibromo-2-nitroethanol and sanguinaria extract, and (in) a surfactant/dispersant, 10 and wherein the composition comprises (l) at least 0 1 ppm of said oxidant, (n) at least 0 1 ppm of said microbiocide, and (in) about 5 ppm of said surfactant/dispersant 15 Also provided in accordance with the present invention is a method for controlling or inhibiting microbial growth m a pulp and paper mill water system comprising adding to the system (1) a microbiocidal effective amount of an oxidant selected from the group 20 consisting of monopersuifates, halogens, halogen releasing compounds, perborates, peroxides, persulfates, permanganates, percarbonates, perorganic acid, chlorine dioxide, ozone, and mixtures thereof, and (i\) a microbiocidal effective amount of a non-oxidizing microbiocide selected from the group consisting of glutaraldehyde, limonene, bis(trichloromethyl) sulfone, 2-(decylthio)-ethanamine, dodecylguanidine hydrochloride, 2-(2-bromo~2-nitroethyl) furan, poly(oxyethylene (dimethyliminio) ethylene (dimethyliminio) ethylene dichloride), alkyl dimethyl benzyl ammonium chloride, alkylamidopropyl propylene glycol dimethyl ammonium chloride phosphate, 2,4,4'-trichloro-2'-hydroxydiphenyl ether, tetrakis-hydroxylmethyl phosphonium sulfate, tributyltetradecyl phosphonium chloride, 2-bromo-2-nitropropane-l, 3-diol, 25 30 2,2—dibromo—2—nitroethanol and sanguinaria extract. intellectual property office of n z 25 FEB 1999 Dtrcn/cn 4a t c. ^ '-N_ 0 DETAILED DESCRIPTION The present invention is directed to certain novel biocidal compositions comprising combinations of oxidants intellectual property office of l\j z 25 FFB 1.q.qq Received WO 96/14092 PCT/US95/13947 5 and non-oxidizing biocides which are added to an aqueous system in amounts effective to inhibit or control the growth of microorganisms in the aqueous system. More particularly, the biocidal compositions of this invention 5 comprise combinations of (l) an oxidant selected from the group consisting of mono- or di-peroxyorganic acids, halogen dioxides, monopersulfates, halogens, halogen releasing compounds, perborates, peroxides, persulfates, permanganates, percarbonates, ozone, their water soluble 10 salts, and mixtures thereof and (n) a non-oxidizing microbiocide selected from the group consisting of glutaraldehyde, limonene, bis(trichloromethyl) sulfone, 2-(decylthio)ethanamine, dodecylguanidine hydrochloride, 2-(2-bromo-2-nitroethyl) furan, poly(oxyethylene 15 (dimethyliminio) ethylene (dimethyliminio) ethylene dichloride), alkyl dimethyl benzyl ammonium chloride, alkylamidopropyl propylene glycol dimethyl ammonium chloride phosphate, 2,4,4'-trichloro-2'-hydroxydiphenyl ether, tetrakis-hydroxylmethyl phosphonium sulfate, 20 tributyltetradecyl phosphonium chloride, 2-bromo-2-nitropropane-1, 3-diol, 2,2-dibromo-2-nitroethanol, sanguinaria extract and optionally in combination with (in) a surfactant/ dispersant, (iv) an anti-corrosive agent and (v) an anti-scale agent. The above oxidants 25 and non-oxidizing microbiocides of this invention are commercially available or may be easily synthesized from commercially available raw materials by known methods. Suitable peroxides include inorganic peroxides such as hydrogen peroxide, sodium peroxide, as well as organic 30 peroxides such as benzoyl peroxide and the like. Suitable halogen releasing compounds include hydantoins such as 1,3-dichloro-5,5-dimethyl hydantom, 1,3-dibromo-5,5-dimethyl hydantoin or l,3-dnodo-5,5-dimethyl hydantoin. Suitable mono- or di-peroxyorganic acids WO 96/1409." PCT/US95/13947 include, but are not limited to, peracetic acid, perbenzoic acid, peroxypropionic acid, hexane diperoxoic acid, dodecanediperoxoic acid. Suitable halogen dioxides include chlorine dioxide, bromine dioxide and iodine 5 dioxide. Specific examples of other suitable oxidants include sodium perborate, sodium percarbonate, potassium permanganate, sodium persulfate, potassium persulfate, ammonium persulfate, chlorine, bromine, iodine and chlorine, bromine, iodine releasing compounds, sodium 10 monopersulfate, potassium monopersulfate, and ammonium monopercarbonate. Potassium monopersulfate is a preferred oxidant and is commercially available from DuPont as OXONE. The combination of the above oxidants and non-15 oxidizing biocides unexpectantly provide enhanced biocidal activity which is greater than that of the individual components which make up the mixtures. The microbiocidal compositions of the present invention possess a high degree of slimicidal activity which could 20 not have been predicted from the known activities of the individual ingredients comprising the combination. The enhanced activity of the mixture permits a significant reduction in the total quantity of the biocide required for an effective treatment of an aqueous system. The 25 enhanced biocidal effectiveness of the compositions of the present invention was particularly surprising since not all oxidants provide enhanced biocidal activity when used m combination with non-oxidizing biocides. In fact, some oxidants are actually antagonistic when used 30 in combination with non-oxidizing biocides, and result m less biocidal effectiveness than the use of either component alone. The biocidal combinations of this invention are effective for ^controlling and inhibiting the growth and WO 96/14092 PCT/US95/13947 reproduction of microorganisms in cooling water systems, pulp and paper mill systems, petroleum operations (e.g. oil well applications), industrial lubricants and coolants, lagoons, lakes and ponds, etc. The particular 5 type of microorganisms present m these areas vary from location to location, and even at a given location over a period of time. Representative examples of microorganisms which may effectively be treated with the biocidal compositions of the present invention include 10 fungi, bacteria and algae and, more particularly, include such genera as Aspergillus, Penicillium, Candida, Saccharomyces, Aerobacter, Escherichia, Alcaligenes, Bacillus, Chlorella, Spirogyra, Oscillatoria, Vaucheria, Pseudomonas, Salmonella, Staphylococcus, Pullularia, 15 Flavobacterium and Rhizopus. In accordance with the invention, an aqueous system is treated to inhibit the growth of the microorganisms by adding to the aqueous system at least one oxidant and at least one non-oxidizing microbiocide. These components 20 are present in the system at the same time. While it is possible to combine the oxidant and the non-oxidizing biocide, it is generally preferred not to combine the microbiocide with the oxidant too far in advance of being added to the aqueous system because these materials may 25 adversely react when they are brought into direct contact with each other in their concentrated forms. The dosage amounts of oxidant and non-oxidizing biocide which are added to an aqueous system may vary widely depending upon the nature of the aqueous system 3 0 being treated, the level of organisms present in the aqueous system and the level of inhibition desired. An important consideration when dosing the oxidants of the present invention are the levels of ferrous iron, reduced manganese, sulfide, ammonia, organic constituents, and WO 96/14092 PCT/US95/13947 8 the like, which may react with and thereby consume the oxidants of the present invention. "Oxidant Demand" refers to the difference between the oxidant dosage amount and the residual oxidant concentration after a 5 prescribed contact time and at a given pH and temperature. "Oxidant Requirement" refers to the oxidant dosage amount required to achieve a given residual oxidant concentration at a prescribed contact time, pH and temperature. Since the levels of ferrous iron, 10 reduced manganese, sulfide, etc. can vary widely from system to system, the oxidant demand should be determined for the aqueous system being treated m accordance with the method of this invention. For purposes of this invention, the dosage amount of oxidant which is added to 15 an aqueous system, i.e., a biocidally effective amount, refers to the residual oxidant concentration m an aqueous system. Residual oxidant concentration can readily be determined by one skilled m the art by conventional means. 20 In general, the dosage amount of oxidant may be from 0.1 ppm to 100 ppm, preferably from about 0.5 ppm to about 45 ppm. The dosage amount of microbiocide in the system may be from 0.1 ppm to 125 ppm, preferably about 0.5 ppm to about 45 ppm. When the microbiocides and 25 oxidants are present xn the above amounts, the resultxng combinatxon possesses a higher degree of effectiveness against mxcroorganxsms than the xndxvidual components comprisxng the combination. While larger quantities of the microbiocides or oxidant may be used with no 30 detrimental effect, such large quantities increase the cost of treatment and generally provide little additional benefit. The biocidal compositions of the present invention may optionally be used in combination with one or more WO 96/14092 PCT/US95/13947 9 surfactants/dispersants to disperse biomass and to enhance the dispersibility and stability of these microbiocidal formulations. Suitable surfactants/ dispersants include, but are not limited to, cationic, 5 nonionic, anionic, or amphoteric surfactants and polymers such as fluormated surfactants, alkylaryl polyether alcohols, polyether alcohols, sodium dodecyl sulfate, sodium nonylbenzene sulfonate, sodium dioctyl sulfosuccmate, octylphenoxypolyethoxyethanol, ethylene 10 and/or propylene oxide condensates with long chained alcohols, mercaptans, amines, carboxylic acids, sodium sulfonate of condensated naphthalene-formaldehyde and lignin sulfonate, alkyl benzene sulfonates and sulfates, sodium linear dodecyl benzene sulfonate, propylene oxide-15 ethylene oxide block copolymers such as, e.g., a polyoxypropylene glycol polymer having a molecular weight of from 1500-2000 which has been reacted with from 5-30% by weight of ethylene oxide (commercially available from BASF as the Pluronic and Tetronic surfactants), and the 20 like. Preferred fluormated surfactants include those manufactured by 3M such as FC-99, FC-100 and FC-129. FC-99 is an anionic surfactant which is a 25% active solution of amine-perfluoroalkyl sulfonates in water. FC-100 is an amphoteric surfactant which is a 2 8% active 25 solution of fluorosurfactant solids in glycol/water. FC-129 is an anionic surfactant which is a 50% solution of potassium fluorinated alkyl carboxylates in water, butyl cellosolve and ethanol. The dosage amount of surfactant/dispersant in the aqueous system is not 30 critical, per se, provided of course that it is added in an amount effective to dispersr the biomass or stabilize a particular microbiocidal formulation. These dosage amounts are typically from 0.5 to 500 ppm. WO 96/14092 PCT/US95/13947 10 The biocidal compositions of the present invention may also be used in combination with an anti-corrosive material. Suitable anti-corrosive materials include, but are not limited to, phosphates such as sodium 5 tripolyphosphate or tetrapotassium pyrophosphate, phosphonates, carboxylates, etc. These components may be added to help protect mild steel from corrosive attack by the oxidant. The antl-corrosive material may be blended with the oxidant before being added to the system or may 10 be added separately. The anti-corrosive material is generally added to the system in a dosage amount of from 0.5 to 50% based on the total amount of oxidant and anti-corrosive material in the mixture. More preferably, tne amount of the anti-corrosive material is at least 1% of 15 the total amount of oxidant and anti-corrosive material in the mixture. The biocidal compositions of this invention may also be used in combination with other biocides which further enhance the synergistic effectiveness. For example, 20 preferred biocidal combinations include glutaraldehyde with isothiazolone. The ratio of these biocidal combinations can range from 1:10 to 10:1 on a weight basis. A preferred isothiazolone is a mixture of 5-chloro-2-methyl~4-isothiazolm-3-one and 2-methyl-4-25 isothiazolm-3-one. The biocidal compositions of the present invention may also be used in combination with an anti-scale material. Suitable anti-scale materials include, but are not limited to, polyaurylates such as sodium 30 polyacrylate, phosphonates such as hydroxyethylidene diphosphonic acid, etc. The anti-scale material is generally added to the system in a dosage amount of from 0.5 to 50% based on the total amount of oxidant and anti-scale material in the mixture! WO 96/14092 PCT/13 S95/13947 11 The oxidants of this invention may be m solid or liquid form and may be diluted with a solid or liquid carrier. Powders may be prepared with a finely divided solid carriers including talc, clay, pyrophyllite, 5 diatomaceous earth, hydrated silica, calcium silicate, or magnesium carbonate. Powders may typically contain 1 to 15 percent of the microbiocides of this invention, while a wettable powder may be obtained by increasing the proportion of microbiocide to about 50 percent or more. 10 A typical formulation of a wettable powder comprises 20 percent to 50 percent of the suitable compounds of this invention, 15 percent to 75 percent of one or more finely divided solids, one percent to five percent of a wetting agent, and one percent to five percent of a dispersing 15 agent. The oxidants of this invention may also be used m the form of liquid concentrates. These are prepared by diluting or dissolving the oxidants and/or microbiocides of this invention in a solvent together with one or more 20 surface active agents. The following examples are provided to illustrate the present invention in accordance with the principles of this invention, but are not to be construed as limiting the invention in any way except as indicated m 25 the appended claims. All parts and percentages are by weight unless otherwise indicated. The synergism of the two-component miciobiocidal combinations of the present invention was demonstrated by testing a wide range of concentrations and ratios of 30 compounds, generated by two-fold serial dilutions m a liquid. The liquid medium is composed of deionized water supplemented with inorganic constituents to simulate an industrial water. Work was performed with the bacterium Enterobacter aerogenes or a mixed bacteria culture WO 96/14092 PCT/US95/13947 12 consisting of Enterobacter aerogenes, Escherichia coli, Pseudomonas aeruginosa, and Bacillus subtilis; the fungus Aspergillus niger; and for the algae, Chlorella vulgaris, or Scenedesmus quadracauda. All organisms were 5 representative of those typically found in industrial waters. Contact periods ranged from 2-24 hours and incubations of subcultures to agar surfaces were conducted at temperatures, times, and lighting conditions permitting the growth of visible colonies. For bacteria 10 the agar was Tryptic Soy, for algae CHU-10, and for fungi Potato Dextrose Yeast Extract. Uniform inoculations within tests of simulated industrial waters were made such that all test-solutions and all exposures of organisms were made with the same density of organisms 15 per ml. After inoculation of the simulated industrial waters these cell-densities were m the thousands per ml for fungi-spores, and algae, and in the millions per ml for bacteria. Following the bacteria-biocide contact in liquid medium and subculture to agar, organic nutrients 20 in the form of sterile Tryptic Soy Broth was added to each tube or well of the bioassay followed by reincubation to determine the viability of any surviving organisms expressed as turbidity (growth). No-growth of bacteria resulted in clear medium without turbidity. 2 5 Various end-points of colony formation were employed for the calculation of synergies from 90 percent to 100 percent reduction as compared to untreated controls. The test results for demonstration of synergism of biocide combinations are illustrated in the following 30 examples. Each table in the examples is organized to show synergy by illustrating (1) the concentration of each test material acting alone required to produce a given end-point of growth prevention or colony-forming-unit WO 96/14092 PCT/US95/13947 13 inhibition as compared to untreated controls; and (2) the lower required concentrations of the combined test materials. Example 1 This example shows synergies between glutaraldehyde and H202 using the bacterium Enterobacter aerogenes and a mixed bacteria culture. WO 96/14092 PCT/US95/13947 10 14 Table 1 Active Biocide Concentrations to Achieve 100% Inhibition of Enterobacter aerogenes, 4 Hours Contact Glutaraldehyde. Ma/1 H;Q;. Ma/1 64 0 0 200 4 6.3 Table 2 Active Biocide Concentrations to Achieve 100% Inhibition of Four Mixed Bacteria Species, 4 Hours Contact 15 Glutaraldehyde. Ma/1 H-,0,. Ma/1 100 0 0 100 3.8 50 7.5 25 20 15 3.1 Example 2- This example demonstrates synergies between 25 glutaraldehyde and H202 using the green algae Chlorella vulgaris and Scenedesmus quadracauda. i WO 96/14092 PCT/U S95/13947 * 15 Table 3 Active Biocide Concentrations to Achieve 100% Inhibition of Cklorella vulgaris plus Unknown Ancillary Bacteria 5 23 Hours Contact Glutaraldehyde. Mq/1 H,0,. Mq/1 >320 0 0 40 5 20 10 Table 4 Active Biocidal Concentrations to Achieve 100% Inhibition of Scenedesmus quadracauda 15 4 Hours Contact Glutar .idehvde. Mo/1 H^O,. Ma/1 80 0 0 40 5 5 20 Example 3 The data (Table 5) indicate hydrogen peroxide as synergist with a combination of glutaraldehyde and Kathon 25 886Ff4:1 active) using the green algae Chlorella vulgaris. Kath n 886F is a mixture of 5-chloro-2-methyl-4-isot^iazolm-3-one and 2-methyl-4-isothiazolin-3-one. WO 96/14092 PCT/US95/13947 16 Table 5 Active Biocide Concentrations to Achieve 100% Inhibition of Chlorella vulgaris 5 2 Hours Contact Glutaraldehyde/Kathon. Mq/1 H70,. Mq/1 416 0 0 100 10 104 6.3 52 12.5 Example 4 This example demonstrates synergies between limonene 15 and oxidizing biocides using a mixture of four bacteria species. Table 6 Active Biocide Concentrations to Achieve 100% Inhibition 20 of Four Mixed Bacteria Species, 4 Hours Contact d-Limonene, Mq/1 H,0,, Mq/1 Peracetic Acid. Mq/1 >2,000 0 0 0 300 0 25 0 0 23.5 31 75 0 31 0 11.8 Example 5 This example demonstrates synergies between 2-(decylthio)-ethanamme (DTEA) and the oxidizing biocide hydrogen peroxide employing a mixed bacteria culture (Table 7). WO 96/14092 PCT/US95/13947 17 Table 7 Active Biocide Concentrations to Achieve 100% Inhibition of Four Mixed Bacteria Species, 4 Hours Contact 5 DTEA. Mq/1 H,0,. Mq/1 100 0 0 100 25 3.1 10 Example 6 This example demonstrates synergies between 2,2-dibromo-2-nitroethanol and the oxidizing biocide hydrogen peroxide. 15 Table 8 Active Biocide Concentrations to Achieve 100% Inhibition of Four Mixed Bacteria Species, 4 Hours Contact 20 2,2-Dibromo-2-nitroethanol, H202/ Mq/1 Ma/1 7.8 0 0 >200 3.9 3.1 25 Example 7 This example demonstrates synergies between poly(oxyethylene (dimethyliminio) ethylene (dimethyliminio) 30 ethylene dichloride) (WSCP) and the oxidizing biocide hydrogen peroxide. In this test the bacterium Enterobacter aerogenes was employed as the test organism. WO 96/14092 PCT/VS9S/13947 18 Table 9 Active Biocide Concentrations to Achieve 100% Inhibition of Enterobacter aerogenes 4 Hours Contact WSCP. Mq/1 &0?, Mg/1 2 C 0 30 1 5 10 Example 8 This example demonstrates synergies between tetradecyl dimethyl benzyl ammonium chloride and the oxidizing biocide 15 hydrogen peroxide. Table 10 Active Biocide Concentrations to Achieve 100% Inhibition 20 of Enterobacter aerogenes 4 Hours Contact Tetradecyl Dimethyl Benzyl H202, Ammonium Chloride. Ma/1 Mq/1 20 0 25 0 100 2.5 20 5 10 Example 9 30 This example demonstrates synergy between tetrakis-hydroxylmethyl phosphonium sulfate and hydrogen peroxide (Table 11). WO 96/14092 PCT/US95/13947 19 Table 11 Active Biocide Concentrations to Achieve 100% Inhibition of Four Mixed Bacteria Species, 5 4 Hours Contact Tetrakis-Hydroxylmethyl H202 Phosphonium Sulfate. Mq/1 Mq/1 31.2 0 0 100 10 15.6 50 Example 10 This example shows synergy between tributyltetradecyl phosphonium chloride and hydrogen 15 peroxide (Table 12). Table 12 Active Biocide Concentrations to Achieve 100% Inhibition of Four Mixed Bacteria Species, 4 Hours Contact 20 Tributyltetradecyl H202 Phosphonium Chloride. Mq/1 Mq/1 31.3 0 0 200 7.8 3.1 25 Example 11 This example demonstrates synergies between 2-bromo-2-nitropropane-l,3-diol and hydrogen peroxide (Table 13). 30 WO 96/14092 PCT/US95/13947 20 Table 13 Active Biocide Concentrations to Achieve 100% Inhibition of Four Mixed Bacteria Species, 5 4 Hours Contact 2-Bromo-2-Nitropropane- H202> 1.3-Diol. Mq/1 Mq/1 62.5 0 0 100 10 7.8 25 15.6 6.3 Example 12 This example demonstrates synergies between 15 cocamidopropyl propylene glycol dimethyl ammonium chloride phosphate and hydrogen peroxide (Table 14). Table 14 Active Biocide Concentrations to Achieve 100% 20 Inhibition of Enterobacter aerogenes 2 Hours Contact Cocamidopropyl Propylene Glycol H202 Dimethyl Ammonium Chloride Phosphate Mq/1 25 Ma/1 78 0 0 200 39 2.5 30 Example 13 This example demonstrates synergies between 2,4,4'-trichloro-2 *-hydroxydiphenyl ether and hydrogen peroxide (Table 15). WO 96/14092 © PCT/US95/13947 21 Table 15 Active Biocide Concentrations to Achieve 100% Inhibition of Four Mixed Bacteria Species, 5 4 Hours Contact 2,4,4,-Tnchloro-2l- H202 Hydroxydiphenyl Ether, Mg/1 Mg/l 500 0 10 0 150 31.2 75 Example 14 15 The data (Table 16) show hydrogen peroxide as a synergist with sanguinaria extract against a mixed bacteria culture. Table 16 20 Active Biocide Concentrations to Achieve 100% Inhibition of Four Mixed Bacteria Species, 4 Hours Contact Sanguinaria Extract, H202i 25 Mct/1 Mcr/1 31.2 0 0 200 3.9 25 7.8 3.1 30 Example 15 This example demonstrates synergies between p ~ly(oxyethylene(dimethyliminio) ethylene(dimethyliminio) ethylene dichloride) (WSCP) and potassium monopersulfate. WO 96/14092 PCT/US95/13947 22 Table 17 Active Biocide Concentrations to Achieve 99.93% Inhibition of Four Mixed Bacteria Species, 5 15 Hours Contact Potassium Monopersulfate, WSCP. Mq/1 Mq/1 16 0 0 >4 10 8 0.5 Example 16 This example shows synergies between glutaraldehyde and sodium hypochlorite. 15 Table 18 Active Biocide Concentrations to Achieve 100% Inhibition of Four Mixed Bacteria Species, 20 4 Hours Contact Sodium Hypochlorite, Glutaraldehyde. Mq/1 Mq/1 as C1-, 25 0 0 >1 25 12.5 0.016 Example 17 This example demonstrates synergies between 30 glutaraldehyde and bromine. WO 96/14092 PCT/US95/13947 23 Table 19 Active Biocide Concentrations to Achieve 100% Inhibition 5 of Four Mixed Bacteria Species, 2 Hours Contact Glutaraldehyde. Mq/1 Bromine. Mq/1 50 0 0 1 10 3.1 0.125 Example 18 The experimental results (Table 20) indicate peracetic 15 acid as a synergist with glutaraldehyde using a mixed bacteria culture. Table 20 Active Biocide Concentrations to Achieve 100% 20 Inhibition of Four Mixed Bacteria Species, 4 Hours Contact Glutaraldehvde. Mq/1 Peracetic Acid. Mg/1 50 0 25 0 25 6.3 6.3 Example 19 30 Additional combinations showing synerg. tic microbiocidal activity ar' * follows: (1) Bis(trichlorome +.) sulfone and potassium percarbonate. WO 96/14092 PCT/US95/13947 24 (2) Dodecylguanidine hydrochloride and sodium perborate. (3) 2-(2-Bromo-2-nitroethy1) furan and ozone. (4) Glutaraldehyde and potassium permanganate. 5 (5) Glutaraldehyde and chlorine dioxide. (6) Tributyltetraderyl phosphonium chloride and sodium persulfate. (7) Bis(trichloromethyl) sulfone and diperoxydodecanoic acid. 10 (8) d-Limonene, hydrogen peroxide and peracetic acid. (9) Glutaraldehyde, hydrogen peroxide and sodium nonylbenzene sulfonate. (10) Glutaraldehyde, peracetic acid and a polyoxypropylene glycol polymer having a molecular 15 weight of 1,650 which has been reacted with 25% by weight of ethylene oxide (Commercially available from BASF as Pluronic L62). (11) d-Limonene, hydrogen peroxide and sodium dioctyl sulfosuccmate. 20 Example 20 In this experiment 4,5-dichloro-l,2-dithiol-3-one(Dithiol) was evaluated under the experimental conditions 25 and found that no synergy existed in inhibition between Dithiol and hydrogen peroxide. The results (Table 21) demonstrated no synergy, but a very strong antagonism between the two test-materials, indicating that not all microbiocides may be combined with an oxidant for 30 controlling the growth and deposition of slime forming microorganisms m water. </div>

Claims

1. WO 96/14092 PCT/US95/13947 10 25 Table 21 Colony-Forming-Unit Survival on Tryptic Soy Agar after 4-Hour Exposure to Combinations of H202 and Dithiol Four Mixed Bacteria Species Number of Colony-Formmg- Treatment Dithiol 15.6 ppm Dithiol 15.6 ppm + H2o2 25 ppm Dithiol 62.5 ppm + H202 25 ppm H202 25 ppm Unit Survival >2 x 10c >2 x 106 >2 x 106 15 WHAT WE CLAIM IS 26 1 A method of inhibiting or controlling the growth and deposition of slime-forming organisms m a pulp and paper water system, which comprises adding to the water system a microbiocidal combination comprising (i) a microbiocidally effective amount of an oxidant, for inhibiting the growth of microorganisms, selected from the group consisting of monopersulfates, halogens, halogen releasing compounds, perborates, peroxides, percarbonates, perorganic acid, chlorine dioxide, persulfates, permanganates, ozone, and mixtures thereof; and (li) a microbiocidally effective amount of microbiocide, for inhibiting the growth of microorganisms, selected from the group consisting of glutaraldehyde, limonene, bis(trichloromethyl) sulfone, 2-(decylthio)-ethanamine, dodecylguanidine hydrochloride, 2-(2-bromo-2-nitroethyl) furan, poly(oxyethylene (dimethyliminio) ethylene (dimethyliminio) ethylene dichloride), alkyl dimethyl benzyl ammonium chloride, alkylamidopropyl propylene glycol dimethyl ammonium chloride phosphate, 2,4,4'-trichloro-2'-hydroxydiphenyl ether, tet^akis-hydroxylmethyl phosphonium sulfate, tributyltetradecyl phosphonium chloride, 2-bromo-2-nitropropane-1,3-diol, 2,2-dibromo-2-nitroethanol, and sanguinaria extract.

2. A method according to Claim 1, wherein the microorganisms comprise algae, bacteria, and fungi.

3. A method according to claim 2, wherein Che water system is a cooling water system. intellectual property office OFNZ 25 FEB 1999 RECEIVED 27 C J

4. A microbiocidal composition comprising: (1) a microbiocidally effective amount of an oxidant or oxidizing biocide, for inhibiting the growth of microorganisms, selected from the group consisting of monopersulfates, halogens, halogen releasing compounds, perborates, peroxides, percarbonates, perorganic acid, chlorine dioxide, persulfates, diperoxydodecanoic acid, permanganates, ozone and mixtures thereof; and (n) a microbiocidally effective amount of a microbiocide, for inhibiting the growth of microorganisms, selected from the group consisting of glutaraldehyde, limonene, bis(trichloromethyl) sulfone, 2-(decylthio)-ethanamine, dodecylguanidine hydrochloride, 2-(2-bromo-2-nitroethyl) furan, poly(oxyethylene (dimethyliminio) ethylene (dimethyliminio} ethylene dichloride), alkyl dimethyl benzyl ammonium chloride, alkylamidopropyl propylene glycol dimethyl ammonium chloride phosphate, 2,4,4'-trichloro-2'-hydroxydiphenyl ether, tetrakis-hydroxylmethyl phosphonium sulfate, tributyltetradecyl phosphonium chloride, 2-bromo-2-nitropropane-l,3-diol, 2,2-dibromo-2-nitroethanol, and sanguinaria extract; and (in) a surfactant/cispersant, and wherein the composition comprises (l) at least 0 1 ppm of said oxidant, (n) at least 0 1 ppm of said microbiocide, and (in) about 5 ppm of said surfactant/dispersant

5. The composition of Claim 4, comprising 0 5 ppm to 45 ppm of said oxidant and 0.5 ppm to 45 ppm of said microbiocide.

6. The composition of Claim 4, wherein the surfactant is a fluorinated surfactant. INTELLECTUAL PROPERTY OFFICE OF N Z 25 FFR 1999 n c r c i w c r\ 28 ' 7 J

7. The composition of Claim 4, further comprising an anti-corrosive material.

8. The composition of Claim 4, further comprising an anti-scale material.

9. The composition of Claim 7, wherein the anti-corrosive material is tetrapotassium pyrophosphate or sodium tripolyphospate.

10. The composition of Claim 8, wherein the anti-scale material is sodium polyacrylate.

11. A microbiocidal combination of materials comprising at least 10 parts by weight of microbiocide and 90 parts by weight of oxidant to 90 parts by weight of microbiocide to 10 parts by weight of oxidant, wherein: (i) said oxidant is selected from the group consisting of potassium monopersulfate, sodium perborate, hydrogen peroxide and sodium percarbonate, and (li) said microbiocide is selected from the group consisting of glutaraldehyde.

12. A microbiocidal composition according to any one of Claims 4 to 11, substantially as herein described

13. A method according to Claim 1, 2 or 3, substantially as herein described eND 05= CLAIMS OFNZ 25 FFR 1999