Methods for treating process water

Abstract

A method of reducing microorganisms in process water includes treating the process water with an organic amine and treating the process water with a biocide comprising methylisothiazolinone and methylchloroisothiazolinone. Treatment with both the biocide and the organic amine reduces microorganism viability in the process water more than treatment with the biocide alone.

Description

METHODS FOR TREATING PROCESS WATERRELATED APPLICATIONS

[0001] The present application is based on and claims priority to U. S. Provisional Patent application Serial No. 63 / 715,118, filed on November 01, 2024, which is incorporated herein by reference.BACKGROUND

[0002] Various industrial processes utilize process water. For instance, paint manufacturing uses process water to maintain equipment. In some processes, the process water is circulated through the equipment to rinse residual product material from the equipment. Over time, these components can accumulate within the process water. Some processes recycle the process water for inclusion in the final products to limit total water usage for the production process.

[0003] Microbial growth in process water can significantly accelerate deterioration of manufacturing plant hygiene, which can lead to product spoilage, operational inefficiency, and other drawbacks, particularly when the process water is recycled for inclusion in the final products. Conventional biocides can treat process water but have limitations. For instance, final product components can interfere with the efficacy of surface-active biocides, such as quaternary ammonium compounds, chlorohexidine, and polyhexanide, and the efficacy of oxidizing biocides, such as chlorine, bromine hydrogen peroxide, and bleach. Conventional biocides can also have compatibility issues with the final products if such biocides pass from the process water into the final products. For instance, surfaceactive biocides can break act as an emulsion-breaker in the final product. As another example, oxidizing biocides can oxidize components of the final product.

[0004] A conventional biocide that avoids the limitations of surface-active and oxidizing biocides is 2,2-dibromo-2-cyanoacetamide, which is commonly referred to as DBNPA. DBNPA has fast activity (e.g., hours timeframe) and subsequently degrades into inert components. Thus, DBNPA is a popular biocide for manufacturing facilities that recycle process water to increase sustainability. However, various biocides, including DBNPA, are under increasing regulatory scrutiny.

[0005] Improved methods for treating process water would be useful. Moreover, methods for treating process water that provide fast activity and are compatible with the final products would be useful.SUMMARY

[0006] The present disclosure is generally directed to methods for treating process water. The methods may include treating the process water with an organic amine and a biocide. The biocide may include methylisothiazolinone (MIT) and methylchloroisothiazolinone (CMIT). The organic amine may advantageously increase reduction of microorganisms present in the process water by the biocide within a useful contact time, enabling more rapid use of the process water in subsequent downstream steps. For instance, a speed-of-kill of the biocide for microorganisms present in the process water may be greater when with both the biocide and the organic amine are present in the process water relative to the biocide alone. Moreover, in some example embodiments, the biocide in combination with the organic amine may provide no less than a 2-log reduction of microorganisms present in the process water within four hours (4 hrs.). In some example embodiments, the organic amine may also advantageously accelerate chemical degradation of the biocide, such as CMIT. For instance, the biocide may be present in the process water at less than fifteen parts per million (15 ppm) within forty-eight hours (48 hrs.). Thus, the method for treating process water may advantageously provide a fast kill rate for microorganisms in the process water while also limiting or preventing compatibility issues with the final product, such as accumulation of the biocide in the final product and associated labelling requirements.

[0007] In example embodiments, a method of reducing microorganisms in process water includes treating the process water with an organic amine and treating the process water with a biocide comprising methylisothiazolinone and methylchloroisothiazolinone. Treatment with both the biocide and the organic amine reduces microorganism viability in the process w ater more than treatment with the biocide alone.

[0008] In example embodiments, a method of reducing microorganisms in process water includes treating the process water with a polyetheramine comprising at least one compound of the Formula I,wherein R1 is H or Ci to C9 alkyl, each of R2, R3, and R4 is independently H or CH3, and each of x, y, and z is independently 1 to 10. The method also includes treating the process water with a biocide comprising methylisothiazolinone and methylchloroisothiazolinone. Treatment with both the biocide and the organic amine reduces microorganism viability in the process water more than treatment with the biocide alone.

[0009] Other features and aspects of the present disclosure are discussed in greater detail below.DETAILED DESCRIPTION

[0010] It is to be understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only and is not intended as limiting the broader aspects of the present disclosure.The present disclosure is generally directed to methods for treating process w ater to reduce microorganisms in process w ater. The methods may include treating the process water with an organic amine, such as a polyetheramine, and treating the process water with a biocide, which may include methylisothiazolinone (MIT) and methylchloroisothiazolinone (CMIT). The biocide may reduce microorganisms present in the process water. However, methylisothiazolinone and methylchloroisothiazolinone alone may have slow- activity and speed-of-kill, e.g., on the order of days. Treatment with both the biocide and the organic amine may advantageously reduce microorganism viability in the process water more than treatment with the biocide alone. For instance, the organic amine may advantageously increase a speed-of-kill of the biocide and thereby improve performance of the biocide at reducing microorganisms present in the process water.

[0011] The organic amine may also accelerate chemical degradation of the biocide. For example, methylisothiazolinone and methylchloroisothiazolinone alone may be relatively chemically stable in process water when the process water is alkaline (e.g., pH 7-9), whichcan lead to retention of the methylisothiazolinone and methylchloroisothiazolinone in the process water such that recycling of the process water into the final product leads to regulatory labeling requirements. Advantageously, the organic amine may accelerate chemical degradation of the biocide in the process water, e.g., by increasing the pH of the process water. Thus, the organic amine may advantageously increase the speed-of-kill of the biocide in the short term (e.g., the two-to-eight-hour time frame) while accelerating chemical degradation of the biocide in the long term (e.g., the twenty-four-to-seventy-two-hour time frame). Treating the process water with the biocide and the organic amine may thus provide fast activity (e.g., hours) while being compatible with the final product when the process water is recycled.

[0012] As used herein, the term ‘‘process water” means any water used in the manufacturing, preparation, or production of goods or materials. Process water may be employed for various applications. For instance, the applications include, but are not limited to, manufacturing and / or processing of metalworking fluids, polymer latex, paints, polymer emulsion, coatings, adhesives, admixtures, spackling and joint compounds, sealants, caulks, mineral and pigment slurries, printing inks, household products, personal care products, leather and hide treatment products, etc. Other processes and applications are also within the scope of the present subject matter. As an example, process water may be used in production of paints or coatings to wash and rinse equipment. Thus, process water may be used to rinse fluids, such as latex emulsions, from mixers, agitators, pumps, and other fluid handling equipment during production of latex paints. Again, process water may be used in other applications as well.

[0013] In example embodiments, the process water may include no less than seventy percent (70%) water by weight of the process water. Moreover, the process water may include less than thirty percent (30%) residual product material by weight of the process water, e.g., after exposure to the product material, such as after washing and rinsing equipment.

[0014] To increase sustainability, at least a portion of the process water may be recycled, e.g., and incorporated into the final product. For instance, the process water used to rinse a paint mixer may be recycled such that a portion of the process water is incorporated into the final paint product. The process water may or may not be treated to remove solids and other additives prior to incorporation into the final product. Moreover, as noted above and discussed in greater detail below, the process water may be treated witha biocide and an organic amine to accelerate reduction of microorganisms in the process water, e.g., prior to incorporation of the process water into the final product.

[0015] The biocide may include at least one isothiazolinone compound. For instance, the isothiazolinone compound may include an isothiazolin-3-one compound. The isothiazolin-3-one compound may include, but is not limited to, l,2-benzisothiazolin-3-one (“BIT”), N-butyl-l,2-benzisothiazolin-3-one (“BBIT”), N-methyl-l,2-benzisothiazolin-3-one (“nMBIT”), 2-methyl-2H-isothiazol-3-one (“MIT”), 5-chloro-2-methyl-2H-isothiazol-3-one (“CMIT”), 2-octyl-3(2H)-isothiazolone (“OIT”), 4,5-dichloro-2n-octyl-3(2H)-isothiazolone (“DCOIT”), 2,2-dithiobis(N-methylbenzamide) (“DTMB”), or a combination thereof. In one example embodiment, the preservative composition disclosed herein may include 2-methyl-2H-isothiazol-3-one (“MIT”) and / or 5-chloro-2-methyl-2H-isothiazol-3-one (“CMIT”).

[0016] In example embodiments, the biocide may include a mixture of MIT and CMIT. MIT and CMIT may be present within the biocide at weight ratio from 2: 1 to 4: 1, such as about 3:1. The biocide, such as a mixture including MIT and CMIT, may reduce microorganism activity within the process water. However, the speed-of-kill provided by the mixture of MIT and CMIT alone may be too slow for effective treatment of the process water. In contrast, MIT and CMIT in combination with the organic amine may increase the speed-of-kill such that the MIT and CMIT provides fast-acting biocidal activity for reducing microorganisms within process water at desirable rates for industrial processes, such as paint production. Thus, treatment with both the biocide and the organic amine may reduce microorganism viability in the process water more than treatment with the biocide alone.

[0017] In example embodiments, the process water may be treated with the biocide such that the biocide is initially present within the process water at a concentration of from about five parts per million (5 ppm) to about five hundred parts per million (500 ppm), such as from about ten parts per million (10 ppm) to about one hundred parts per million (100 ppm), such as from about fifteen parts per million (15 ppm) to about fifty parts per million (50 ppm), or any range therebetween. It will be understood that other biocide concentrations may be utilized depending upon the particular industrial process for the process water. As described herein, the organic amine may accelerate chemical degradation of the biocide in the long term. Thus, the concentrations of the biocide in the process water recited above may correspond to the concentrations of the biocide in the process water within two-to-eight hours after treating the process water with the biocide. Theconcentration of the biocide in the process water may decrease after such time frame due to the organic amine accelerating chemical degradation of the biocide (e.g., unless additional process water is retreated with biocide as described below).

[0018] The biocide may be effective against bacteria and / or fungi in the process water. Exemplary microorganisms can include one or more species from one or both of the following groups.

[0019] Bacteria: Alcaligenes such as Alcaligenes faecalis, Acinetobacter such as Acinetobacter calcoaceticus, Bacillus such as Bacillus subtilis, Citrobacter such as Citrobacter freundii, Corynebacterium such as C 'orynebacterium ammoniagenes, Enterobacter such as Enterobacter aerogenes or Enterobacter cloacae, Enterococcus such as Enterococcus hirae, Escherichia such as Escherichia coli, Proteus such as Proteus hauseri, Pseudomonas such as Pseudomonas aeruginosa. Pseudomonas fluorescens, or Pseudomonas stutzeri, Salmonella such as Salmonella enterica, Staphylococcus such as Staphylococcus aureus,'

[0020] Fungi: Acremonium such as Acremonium strictum, Altemaria such as Alternaria tenuis or Alternaria alternata, Aspergillus such as Aspergillus nlger or Aspergillus brasiliensis, Candida such as Candida albicans, Chaetomium such as Chaetomium globosum, Fusarium such as Fusarium solani, Geotrichum such as Geotrichum candidum, Lentinus such as Lentinus tigrinus, Penicillium such as Penicillium glaucum, Penicillium funiculosum, or Penicillium pinophilum, Rhodotorula such as Rhodotorula rubra or Rhodotorula mucilaginosa, Stachybotrys such as Stachybotrys chartarum, Trichoderma such as Trichoderma virens.

[0021] The organic amine may include at least one poly etheramine. In example embodiments, two or more poly etheramines may be used to treat the process water.

[0022] The polyetheramine(s) may have the following formula (I):R-(R1)(R2)(R3)(R4) (I),wherein R is C*(CH2—)4 (tetrafunctional), CH3CH2C*(CH2— )3 (trifunctional), CH3C*H= (difunctional), — H2C(C6HIO)*CH2— (difunctional), CI FOCI EC*! I2— (monofunctional), or a combination thereof; and Ri. R2, Rs, R4 are independently — H, — NH2.— (OCH2CHR’)nNH2, or a combination thereof; and wherein R’ is H or Cl-9 alkyl chain and n = 1 to 2. In Formula (I), R may be the junction point (*: junction carbon atom) of multiple poly etheramine chains and not limited to the exemplary structures disclosed herein.

[0023] In example embodiments, the polyetheramine may be an organic aliphatic polyamine. For instance, the poly etheramine may be polyoxypropylenediamine or polyoxyprolyenetriamine. In one example embodiment, the polyetheramine of Formula I is Jeffamine® T403 polyetheramine (Huntsman Corp., Houston, Texas).

[0024] In other example embodiments, the poly etheramine may be a linear polyetheramine. The linear polyetheramine may have a molecular weight greater than about 118 Daltons (Da). For instance, the linear polyetheramine may have a molecular weight greater than about 150 Da, such as greater than about 200 Da, such as greater than about 230 Da, such as greater than about 300 Da, such as greater than about 400 Da, such as greater than about 500 Da, such as greater than about 600 Da, such as greater than about 800, such as greater than about 900 Da, such as greater than 1500 Da. such as greater than about 2000 Da, or such as greater than about 2500 Da. The linear polyetheramine may have the following formulaIn one example embodiment, the linear polyetheramine of Formula I may include, but is not limited to, JEFF AMINE® ED900, JEFF AMINE® D2000, JEFFAMINE® ED600, JEFFAMINE® D400, JEFFAMINE® D230, JEFFAMINE® M2005, JEFFAMINE® M600, and combinations thereof.

[0025] In example embodiments, the polyetheramine may be a cycloaliphatic poly etheramine. For instance, the poly etheramine of Formula 1 may be JEFFAMINE® RFD270. RFD270 is a reaction product of 1,4-cyclohexyanedimethanol, propylene oxide, and ammonia.

[0026] In example embodiments, the polyetheramine may have the structure of Formula II:wherein R1 is H or Ci to C9 alkyl, each of R2, R3, and R4 is independently H or CH3, and each of x, y, and z is independently 1 to 10.

[0027] The degree of polymerization (x. y, and z) of Formula I may be independently one (1) to ten (10). The polymerization degrees x, y, and z can be the same or different in some instances. For instance, x may be one, y may be two, and z may be three. In another instance, x, y, and z may each be two. In one example embodiment, the sum of polymerization (e.g., the total of x, y, and z values) is no less than five (5), such as six (6), seven (7), eight (8), nine (9), or ten (10). In one example embodiment, the sum of x, y, and z values is no greater than ten (10).

[0028] As noted above, the poly etheramine may be a primary aliphatic poly amine. For instance, the polyetheramine may be polyoxypropylenediamine or polyoxyprolyenetriamine. In one example embodiment, the polyetheramine of Formula II may be Jeffamine® T403 polyetheramine (Huntsman Corp., Houston, Texas).

[0029] Other organic amines may include, but are not limited to, 2-amino-2-methyl-l-propanol ("AMP95"). monoethanolamine, l-amino-2-propanol, 3-amino-l -propanol. 2-(methylamino)ethanol. 2-(ethylamino)ethanol, 2(propylamino)ethanol, 2(isopropylamino)ethanol, diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine,, 2-amino-2-ethyl-l,3-propanediol (also called AEPD), 2(2-aminoethoxy)ethanol (also called diglycol amine), N-methyldiethanolamine, N, N-dimethylethanolamine. N, N-diethylethanolamine, N, N-dibutylaminoethanol, N, N dimethylammo-2-propanol, etc. The organic amines described above may be used individually or in any combination.

[0030] The process w ater may be treated with the organic amine such that the organic amine is present within the process water at a concentration of from about fifty parts per million (50 ppm) to about twenty-thousand parts per million (20,000 ppm), such as from about two hundred parts per million (200 ppm) to about ten-thousand parts per million (10,000 ppm), such as from about five hundred parts per million (500 ppm) to about five-thousand parts per million (5000 ppm), or any range therebetween. It will be understood that other organic amine concentrations may be utilized depending upon the particular industrial process for the process water and / or the concentration of the biocide present in the process w ater.

[0031] As noted above, the organic amine may advantageously increase the speed-of-kill of the biocide in the process water compared to the biocide alone. For instance, the biocide, such as MIT and CM1T. alone may have a speed-of-kill of two or more days for a2-log reduction of microorganisms present in the process water. Conversely, the biocide may have a significantly faster speed-of-kill when the organic amine is also present in the process water. For instance, the biocide, such as a mixture of MIT and CMIT, in combination with the organic amine may have a speed-of-kill of less than six hours for a 2-log reduction of microorganisms present in the process water.

[0032] In example embodiments, the biocide may treat the process water such that the microorganisms present in the process water are reduced by no less than 2-log within six hours, such as within four hours, such as within three hours. As another example, the biocide may treat the process water such that the microorganisms present in the process water are reduced by no less than 3-log within six hours, such as within four hours, such as within three hours. Thus, the organic amine may advantageously increase a speed-of-kill of the biocide and thereby improve performance of the biocide for reducing microorganisms present in the process water.

[0033] In addition to increasing the speed-of-kill of the biocide in the process water, the organic amine may also accelerate chemical degradation of the biocide. Moreover, as noted above, the organic amine may advantageously increase the speed-of-kill of the biocide in the short term (e.g., the two-to-eight-hour time frame) while accelerating chemical degradation of the biocide in the long term (e.g., the twenty-four-to-seventy-two-hour time frame). In example embodiments, the primary amine may accelerate chemical degradation of the biocide such that the biocide is present within process water at less than fifteen parts per million (15 ppm), such as less than ten parts per million (10 ppm), such as less than five parts per million (5 ppm), after forty-eight hours. At least a portion of the process water may be recycled, e.g., and incorporated into a final product, after the biocide chemically degrades.

[0034] Due to the organic amine accelerating chemical degradation of the biocide (e.g., in the long term), the methods of the present disclosure may also include retreating the process water with the biocide. For instance, after initially treating the process w ater with the biocide, the biocide may chemically degrade, e.g., such that the biocide is present within process water at less than fifteen parts per million (15 ppm). Retreating the process w ater with the biocide may thus increase the concentration of the biocide in the process water back to an amount for fast-acting biocidal activity to reduce microorganisms within process w ater. As noted above, at least a portion of the process water may be recycled into the final product. The organic amine may accelerate chemical degradation of the biocide is such portion of the process water that is recycled into the final product while the remainingprocess water may be retreated with the biocide to reduce microorganisms within process water.

[0035] In example embodiments, immediately prior to retreating the process water with the biocide, the biocide may be present within process water at less than fifteen parts per million (15 ppm). After retreating the process water with the biocide, the biocide may again be initially present within the process water at a concentration of from about fifteen parts per million (15 ppm) to about fifty parts per million (50 ppm) or more.

[0036] Optionally, the method may also include treating the process water with at least one additive or booster including, but are not limited to, an inorganic metal compound, a silicate, an alkali compound, or a combination thereof.

[0037] If desired, the inorganic metal compound may include, but is not limited to, an inorganic zinc compound, an inorganic magnesium compound, an inorganic copper compound, an inorganic lithium compound, or a combination thereof. In example embodiments, the inorganic metal compound is an inorganic zinc compound, such as one or more of zinc oxide (at times referred to herein as “ZnO”), zinc acetate, zinc oxide, zinc sulfate, zinc chloride, and zinc carboxylate. Preferably, the zinc oxide may have a zinc oxide particle size of less than fifty (50) microns. In example embodiments, the inorganic metal compound may be an inorganic magnesium compound, such as magnesium oxide. In example embodiments, the inorganic metal compound may be an inorganic copper compound, such as copper salts. For instance, copper salt may include copper sulfate, copper nitrate, copper carbonate, copper carbonate hydroxide, copper oxide, copper oxychloride, copper hydroxide, copper acetylacetonate, copper pyrrolidone carboxylic acid (PCA), copper PCA methylsilanol, copper acetyl tyrosinate methylsilanol, copper acetylmethionate, copper aminoacetylamidoimidazolyl propionate, copper picolinate, copper tripeptide- 1, bis (tripeptide- 1) copper acetate, copper ascorbyl phosphate succinoyl tripeptide-34, copper pyrithione, sodium calcium copper phosphate, copper pyridoxal-5-phosphate, sodium copper chlorophyllin, copper chlorophyll, disodium EDTA copper, or a combination thereof. In one embodiment, the copper salt may include one or more of copper sulfate, copper nitrate, copper carbonate, copper oxide, and copper acetylacetonate. In example embodiments, the inorganic metal compound may be an inorganic lithium compound, such as lithium salts. For instance, lithium salts may include lithium carbonate, lithium acetate, lithium fluoride, lithium sulfate, lithium nitrate, lithium tetraborate, lithium metaborate, lithium pyrophosphate, lithium tripolyphosphate, lithium orthosilicate, lithium metasilicate, or a combination thereof.

[0038] If desired, the silicates may include, but are not limited to, silicas such as modified silicas and fumed silicas. In example embodiments, the silicate may be one or both of potassium methylsilicionate and sodium metasilicate (e.g., sodium metasilicate pentahydrate). Commercial examples include Silres 168 (Wacker), Tyson WR50 (Tyson, Singapore), and Xiameter OFS-0777 (Corning).

[0039] If desired, the alkali compound may include, but are not limited to, potassium / sodium methyl siliconate. potassium / sodium hydroxide, potassium / sodium carbonate / bicarbonate, or a combination thereof.

[0040] The process water may be treated with one or more other components, in addition to those mentioned above. Additional optional components include, but are not limited to, dispersants, defoamers (antifoams, e.g., silicone-based defoamers, mineral oil-based defoamers, hydrophobic silica-based defoamers), sequestering / chelating agents, corrosion inhibitors (anti-corrosion additives), antioxidants, solvents, co-solvents, scale inhibitors, and the like.

[0041] In example embodiments, a method of reducing microorganisms in process water includes treating the process water with an organic amine and treating the process water with a biocide that includes MIT and CMIT. The treatment of the process water with the organic amine and the biocide may be taken in any order. For instance, the process water may first be treated with the organic amine and then subsequently treated with the biocide. As another example, the process water may first be treated with the biocide and then subsequently treated with the organic amine. In other examples, the process water may be simultaneously treated with the organic amine and the biocide.

[0042] After treating the process water with the biocide, the biocide may reduce microorganisms present in the process water. Treating the process water with the organic amine may advantageously increase a speed-of-kill of the biocide and thereby improve performance of the biocide for reducing microorganisms present in the process water. Moreover, treating the process water with both the biocide and the organic amine may reduce microorganism viability in the process water more than treatment with the biocide alone. Treating the process water with the organic amine may also advantageously accelerate chemical degradation of the biocide. Moreover, the organic amine may advantageously increase the speed-of-kill of the biocide in the short term (e.g., the two-to-eight-hour time frame) while accelerating chemical degradation of the biocide in the long term (e.g., the twenty-four-to-seventy-two-hour time frame). The process water may be retreated with the biocide to account for the long-term chemical degradation of the biocide.In example embodiments, the concentration of the organic amine may remain stable relative to the concentration of the biocide. Thus, the process water may not require retreatment of the process water with the organic amine or may require less frequent retreatment with the organic amine relative to the biocide.

[0043] In example embodiments, the process water may also be heated to accelerate chemical degradation of the biocide in the process water. For instance, the process water may be heated to no less than forty degrees Celsius (40° C) and no greater than sixty degrees Celsius (60° C) to assist with chemical degradation of the biocide in the process water. Thus, in addition to treating the process water with the organic amine, the methods described herein may also include heating the process water. The heated process water may include both the biocide and the organic amine, and the heated process water may assist with chemical degradation of the biocide in the process water.

[0044] The preceding description is exemplary in nature and is not intended to limit the scope, applicability or configuration of the disclosure in any way. Various changes to the described embodiments may be made in the function and arrangement of the elements described herein without departing from the scope of the disclosure.

[0045] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention is related.

[0046] As used in this application and in the claims, the singular forms “a”, “an”, and “the” include the plural forms unless the context clearly dictates otherwise. Additionally, the term ‘'includes” means “comprises”. The methods and compositions of the present disclosure, including components thereof, can comprise, consist of, or consist essentially of the essential elements and limitations of the embodiments described herein, as well as any additional or optional ingredients, components or limitations described herein or otherwise useful in preservative compositions.

[0047] Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight, percentages, and so forth, as used in the specification or claims are to be understood as being modified by the term “about”. Accordingly, unless otherwise indicated, implicitly or explicitly, the numerical parameters set forth are approximations that may depend on the desired properties sought and / or limits of detection under standard test conditions / methods. When directly and explicitly distinguishing embodiments from discussed prior art. the embodiment numbers are not approximates unless the word “about” is recited.

[0048] As used herein, “optional” or “optionally” means that the subsequently described material, event or circumstance may or may not be present or occur, and that the description includes instances where the material, event or circumstance is present or occurs and instances in which it does not. As used herein, “w / w%” and “wt%” mean by weight as relative to another component or a percentage of the total weight in the composition.

[0049] The term “about” is intended to mean approximately, in the region of. roughly, or around. When the term “about” is used in conjunction with a numerical range, it modifies that range by extending the boundaries above and below the numerical values set forth. Unless otherwise indicated, it should be understood that the numerical parameters set forth in the following specification and attached claims are approximations. At the very-least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, numerical parameters should be read in light of the number of reported significant digits and the application of ordinary- rounding techniques.

[0050] The term “substantially free of’ when used to describe the amount of substance in a material is not to be limited to entirely or completely free of and may correspond to a lack of any appreciable or detectable amount of the recited substance in the material. Thus, e.g., a material is “substantially free of’ a substance when the amount of the substance in the material is less than the precision of an industry -accepted instrument or test for measuring the amount of the substance in the material. In certain example embodiments, a material may be “substantially free of’ a substance when the amount of the substance in the material is less than 10%, less than 9%, less than 8%, less than 7%, less than 6%, less than 5%, less than 4%, less than 3%, less than 2%, less than 1%, less than 0.5%, or less than 0.1% by weight of the material.

[0051] The phrase “effective amount” means an amount of a compound that promotes, improves, stimulates, or encourages a response to the particular condition or disorder or the particular symptom of the condition or disorder.

[0052] The term “biocidal agent” as used herein refers to any chemical compound that is intended to inhibit or kill organisms on a surface and / or that prevents or kills the growth of organisms in an aqueous solution, such as process water.

[0053] As used herein, the terms “first”, “second”, and “third” may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components.

[0054] Here and throughout the specification and claims, range limitations are combined and interchanged, such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise. For example, all ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other.

[0055] This written description uses examples to disclose the present disclosure, including the best mode, and also to enable any person skilled in the art to practice the disclosure, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the disclosure is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.

[0056] Furthermore, certain aspects of the present disclosure may be better understood according to the following examples, which are intended to be non-limiting and exemplary in nature. Moreover, it will be understood that the compositions described in the examples may be substantially free of any substance not expressly described.EXAMPLES

[0057] Bacterial Kill Rates

[0058] The effect of adding various organic amines to process water on a speed-of-kill of a biocide in the process water was evaluated. In particular, the viability of a mixed bacterial culture in simulated process water was monitored over four hours. Surprisingly, the speed-of-kill of the biocide in the process water was significantly greater in the presence of the organic amines as compared to the biocide alone.

[0059] The biocide was Mergal CM1.5, which incudes MIT and CMIT. The process water was prepared by adding one-part unpreserved water-based acry lic paint formulation to four-parts sterile deionized water by weight and mixing well. The mixed bacterial culture was prepared by blending equal volumes of overnight Tryptic Soy Broth (TSB) cultures ofAlcaligenesfaecalis, Enterobacter aerogenes, Escherichia coli. Pseudomonas aeruginosa. Staphylococcus aureus, Microbacterium paraoxydans, Burkholderia cenocepacia, Citrobacter werkmanii, and Acinetobacter sp. and standardizing the mixed culture to about 109CFU / mL.

[0060] Treated samples were prepared in 100g aliquots using an analytical balance, and 15g were removed to inoculate with the standardized mixed culture at 1 %v / w to provide an initial about 107CFU / g in all test samples. The inoculated samples were then incubated at 37°C with shaking at 200 rpm for four hours before 0.1mL of each sample was removed, neutralized in 9.9mL of Dey-Engley neutralizing broth, and quantified with serial dilution into lx Butterfield's Phosphate Buffer (pH 7) and pour plates with Tryptic Soy Agar. The plates were incubated for forty-eight hours at 32°C before reading. The remainder of the sample was used for analytical measurements of biocide content and pH readings using an OrionStar A111 pH probe freshly calibrated between 7 and 10.

[0061] The pH of the untreated and treated process water, with and without the biocide (from 0.25 %w / w Mergal CM1.5), at the beginning of the testing and before inoculation is below shown in Table 1.

[0062] The log reductions and synergy calculations in the mixed bacterial culture after four hours of incubation are shown below in Table 2.

[0063] The Bliss predicted inhibition rate (Yab) for log reductions was calculated by the following equation:Yab =Ya + Yb-Ya*Yb

[0064] Yais the log reduction occurring in the absence of the biocide at the pH value closest to pH of the treatment, and Yb is the log reduction caused by 0.25 %w / w of thebiocide at the pH value closest to the pH of the treatment. A treatment combination is considered non-additive if the observed value is higher than the predicted value.

[0065] The log reduction and pH data in Tables 1 and 2 show that increasing the pH of the process water to about 9.5 with sodium hydroxide (NaOH) did not improve the observed log reduction of treatment with the biocide after four hours of treatment. In contrast, a combination of 0.20 %w / w of all four tested organic amines with about 37.5 ppm of the biocide caused log reductions higher than predicted by the effects of the individual components.Biocide Chemical Degradation Rate

[0066] The effect of the various organic amine treatments on the concentration of the biocide in the process water was also evaluated in uninoculated samples within one hour of sample preparation and after one day and after two days of incubation at 40°C. All the tested samples contained 0.25 %w / w of the biocide. The concentrations were measured with HPLC after extraction in acetonitrile, mixing, centrifugation, and filtering through a 0.2 micron nylon syringe filter. The standard used was the biocide, Mergal MC14 (14% CMIT / MIT).

[0067] As may be seen from the above, all sample organic amines significantly accelerate decomposition of the CMIT and brought the concentration of the CMIT significantly below fifteen parts per million (15 ppm).

[0068] These and other modifications and variations to the present invention may be practiced by those of ordinary skill in the art, without departing from the spirit and scope of the present invention, which is more particularly set forth in the appended claims. In addition, it should be understood that aspects of the various embodiments may be interchanged both in whole or in part. Furthermore, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only, and is not intended to limit the invention so further described in such appended claims.EXAMPLE EMBODIMENTS

[0069] First example embodiment: A method of reducing microorganisms in process water, comprising: treating the process water with an organic amine; and treating the process water with a biocide comprising methylisothiazolinone and methylchloroisothiazolinone, wherein treatment with both the biocide and the organic amine reduces microorganism viability in the process water more than treatment with the biocide alone.

[0070] Second example embodiment: The method of the first example embodiment, wherein the process water is simultaneously treated with the organic amine and the biocide.

[0071] Third example embodiment: The method of the first or second example embodiment 1, wherein the process water is treated with the organic amine and then treated with the biocide.

[0072] Fourth example embodiment: The method of any one of the first through third example embodiments, wherein the process water is treated with the biocide and then treated with the organic amine.

[0073] Fifth example embodiment: The method of any one of the first through fourth example embodiments, wherein treating the process water with the organic amine increases a pH of the process water.

[0074] Sixth example embodiment: The method of any one of the first through fifth example embodiments, wherein the biocide and organic amine combination treats the process water such that the microorganisms present in the process water are reduced by no less than 2-log within four hours.

[0075] Seventh example embodiment: The method of any one of the first through sixth example embodiments, wherein the biocide and organic amine combination treats the process water such that the microorganisms present in the process water are reduced by no less than 3-log within four hours.

[0076] Eighth example embodiment: The method of any one of the first through seventh example embodiments, wherein, after treating the process water with the biocide, the biocide is initially present within the process water at no less than fifteen parts per million and no greater than fifty parts per million.

[0077] Ninth example embodiment: The method of any one of the first through eighth example embodiments, wherein, after treating the process water with the biocide, the organic amine is present within the process water at no less than five hundred parts per million and no greater than five thousand parts per million.

[0078] Tenth example embodiment: The method of the eighth example embodiment, further comprising retreating the process water with the biocide.

[0079] Eleventh example embodiment: The method of the tenth example embodiment, wherein the organic amine causes degradation of the biocide in the process water.

[0080] Twelfth example embodiment: The method of any one of the first through eleventh example embodiments, wherein treating the process water with the primary amine further comprises treating the process water with the primary amine in order to accelerate chemical degradation of the biocide.

[0081] Thirteenth example embodiment: The method of the twelfth example embodiment, wherein the primary amine accelerates the chemical degradation of the biocide such that the biocide is present within process water at less than fifteen parts per million after forty-eight hours.

[0082] Fourteenth example embodiment: The method of any one of the first through thirteenth example embodiments, wherein the organic amine comprises a poly etheramine.

[0083] Fifteenth example embodiment: The method of the fourteenth example embodiment, wherein: the poly etheramine comprises at least one compound of the Formula I,(I); and R1 is H or Ci to C9 alkyl, each of R2, R3, and R4 is independently H or CH3, and each of x, y, and z is independently 1 to 10.

[0084] Sixteenth example embodiment: The method of either the fourteenth or fifteenth example embodiment, wherein: the polyetheramine comprises at least one compound of the Formula I, R-(RI)(R2)(RJ)(R4) (I): and R is C*(CH2—)4 (tetrafunctional), CH3CH2C*(CH2— )3 (trifunctional), CH3C*H= (difunctional), — H2C(CeHio)*CH2— (difunctional), CH3OCH2C*H2— (monofunctional), or a combination thereof: Ri. R2. R3, R4 are independently — H, — NH2, — (OCFECHR’lnNFh, or a combination thereof; and R’ is H or C 1-9 alkyl chain and n = 1 to 20.

[0085] Seventeenth example embodiment: The method of any one of the first through sixteenth example embodiments, wherein a weight ratio of the methylisothiazolinone to the methylchloroisothiazolinone in the biocide is between 1: 1 and 5:1.

[0086] Eighteenth example embodiment: The method of the seventeenth example embodiment, wherein the weight ratio of the methylisothiazolinone to the methylchloroisothiazolinone in the biocide is about 3:1.

[0087] Nineteenth example embodiment: The method of any one of the first through eighteenth example embodiments, wherein the process water comprises process water for paints or coatings.

[0088] Twentieth example embodiment: The method of the nineteenth example embodiment, wherein the process water comprises process water for latex paints.

[0089] Twentieth-first example embodiment: The method of any one of the first through tw entieth example embodiments, wherein the process water comprises no less than seventy percent water by weight of the process water.

[0090] Twentieth-second example embodiment: A method of reducing microorganisms in process water, comprising: treating the process water with a polyetheramine comprising at least one compound of the Formula I,(I), wherein R1 is H or Ci to C9 alkyl, each of R2, R3, and R4 is independently H or CH3. and each of x, y, and z is independently 1 to 10; and treating the process water with a biocide comprising methylisothiazolinone and methylchloroisothiazolinone, wherein treatment with both the biocide and the organic amine reduces microorganism viability in the process water more than treatment with the biocide alone.

[0091] Twentieth-third example embodiment: The method of the twentieth-second example embodiment, wherein the process water is simultaneously treated with the polyetheramine and the biocide.

[0092] Twentieth-fourth example embodiment: The method of the twentieth-second example embodiment, wherein the process water is treated with the polyetheramine and then treated with the biocide.

[0093] Twentieth-fifth example embodiment: The method of the twentieth-second example embodiment, wherein the process water is treated with the biocide and then treated with the poly etheramine.

[0094] Twentieth-sixth example embodiment: The method of any one of the twentieth-second through twentieth-fifth example embodiments, wherein treating the process water with the polyetheramine increases a pH of the process water.

[0095] Twentieth-seventh example embodiment: The method of any one of the twentieth-second through twentieth-sixth example embodiments, wherein the biocide and organic amine combination treats the process water such that the microorganisms present in the process water are reduced by no less than 2-log within four hours.

[0096] Twentieth-eighth example embodiment: The method of the twentieth-seventh example embodiment, wherein the biocide and organic amine combination treats the process water such that the microorganisms present in the process water are reduced by no less than 3-log within four hours.

[0097] Twentieth-ninth example embodiment: The method of any one of the twentieth-second through twentieth-eighth example embodiments, wherein, after treating the process water with the biocide, the biocide is initially present within the process water at no less than fifteen parts per million and no greater than fifty parts per million.

[0098] Thirtieth example embodiment: The method of the twentieth-ninth example embodiment, wherein, after treating the process water with the biocide, the poly etheramine is present within the process water at no less than five hundred parts per million and no greater than five thousand parts per million.

[0099] Thirtieth-first example embodiment: The method of the twentieth-ninth example embodiment, further comprising retreating the process water with the biocide.

[0100] Thirtieth-second example embodiment: The method of the thirtieth-first example embodiment, wherein the polyetheramine causes degradation of the biocide in the process water.

[0101] Thirtieth-third example embodiment: The method of any one of the twentieth-second through thirtieth-second example embodiments, wherein treating the process water with the polyetheramine further comprises treating the process water with thepoly etheramine in order to accelerate chemical degradation of the biocide.

[0102] Thirtieth-fourth example embodiment: The method of the thirtieth-third example embodiment, wherein the primary amine accelerates the chemical degradation of the biocide such that the biocide is present within process water at less than fifteen parts per million after forty-eight hours.

[0103] Thirtieth-fifth example embodiment: The method of any one of the twentieth-second through thirtieth-fourth example embodiments, wherein a weight ratio of themethylisothiazolinone to the methylchloroisothiazolinone in the biocide is between 1:1 and 5:1.

[0104] Thirtieth-sixth example embodiment: The method of the thirtieth-fifth example embodiment, wherein the weight ratio of the methylisothiazolinone to the methylchloroisothiazolinone in the biocide is about 3:1.

[0105] Thirtieth-seventh example embodiment: The method of any one of the twentieth-second through thirtieth-sixth example embodiments, wherein the process water comprises process water for paints or coatings.

[0106] Thirtieth-eighth example embodiment: The method of the thirtieth-seventh example embodiment, wherein the process water comprises process water for latex paints.

[0107] Thirtieth-ninth example embodiment: The method of any one of the twentieth-second through thirtieth-eighth example embodiments, wherein the process water comprises no less than seventy percent water by weight of the process water.

[0108] Fortieth example embodiment: A method of treating process water substantially as described herein.

Claims

What Is Claimed:

1. A method of reducing microorganisms in process water, comprising:treating the process water with an organic amine; andtreating the process water with a biocide comprising methylisothiazolinone and methylchloroisothiazolinone,wherein treatment with both the biocide and the organic amine reduces microorganism viability in the process water more than treatment with the biocide alone.

2. The method of claim 1, wherein the process water is simultaneously treated with the organic amine and the biocide.

3. The method of claim 1, wherein the process water is treated with the organic amine and then treated with the biocide.

4. The method of claim 1, wherein the process water is treated with the biocide and then treated with the organic amine.

5. The method of claim 1. wherein treating the process water with the organic amine increases a pH of the process water.

6. The method of claim 1, wherein the biocide and organic amine combination treats the process water such that the microorganisms present in the process water are reduced by no less than 2-log within four hours.

7. The method of claim 6, wherein the biocide and organic amine combination treats the process water such that the microorganisms present in the process water are reduced by no less than 3-log within four hours.

8. The method of claim 1, wherein, after treating the process water with the biocide, the biocide is initially present within the process water at no less than fifteen parts per million and no greater than fifty parts per million.

9. The method of claim 8, wherein, after treating the process water with the biocide, the organic amine is present within the process water at no less than five hundred parts per million and no greater than five thousand parts per million.

10. The method of claim 8, further comprising retreating the process water with the biocide.

11. The method of claim 10, wherein the organic amine causes degradation of the biocide in the process water.

12. The method of claim 1. wherein treating the process water with the primary amine further comprises treating the process water with the primary amine in order to accelerate chemical degradation of the biocide.

13. The method of claim 12, wherein the primary amine accelerates the chemical degradation of the biocide such that the biocide is present within process water at less than fifteen parts per million after forty-eight hours.

14. The method of claim 1, wherein the organic amine comprises a poly etheramine.

15. The method of claim 14, wherein:the polyetheramine comprises at least one compound of the Formula I,(I); andR1 is H or Ci to C9 alkyl, each of R2, R3, and R4 is independently H or CH3, and each of x, y, and z is independently 1 to 10.

16. The method of claim 14, wherein:the polyetheramine comprises at least one compound of the Formula I, R-(R1)(R2)(R3)(R4) (I); andR is C*(CH2—)4 (tetrafunctional), CH3CH2C*(CH2— )? (trifunctional), CHsC*H= (difunctional), — H2C(C6HIO)*CH2— (difunctional), CHsOCH2C*H2— (monofunctional), or a combination thereof;Ri, R2, RS, R4 are independently — H. — NH2, — (OCH2CHR )nNH2, or a combination thereof; andR’ is H or Cl -9 alkyl chain and n = 1 to 20.

17. The method of claim 1, wherein a weight ratio of the methylisothiazolinone to the methylchloroisothiazolinone in the biocide is between 1: 1 and 5:1.

18. The method of claim 17, wherein the weight ratio of the methylisothiazolinone to the methylchloroisothiazolinone in the biocide is about 3:1.

19. The method of claim 1, wherein the process water comprises process water for paints or coatings.

20. The method of claim 19, wherein the process water comprises process water for latex paints.

21. The method of claim 1, wherein the process water comprises no less than seventy percent water by weight of the process water.

22. A method of reducing microorganisms in process water, comprising:treating the process water with a polyetheramine comprising at least one compound of the Formula I,(I). wherein R1 is H or Ci to C9 alkyl, each of R2, R3, and R4 is independently H or CH3, and each of x, y. and z is independently 1 to 10; andtreating the process water with a biocide comprising methylisothiazolinone and methylchloroisothiazolinone,wherein treatment with both the biocide and the organic amine reduces microorganism viability in the process water more than treatment with the biocide alone.

23. The method of claim 22, wherein the process water is simultaneously treated with the polyetheramine and the biocide.

24. The method of claim 22, wherein the process water is treated with thepoly etheramine and then treated with the biocide.

25. The method of claim 22, wherein the process water is treated with the biocide and then treated with the polyetheramine.

26. The method of claim 22, wherein treating the process water with thepoly etheramine increases a pH of the process water.

27. The method of claim 22, wherein the biocide and organic amine combination treats the process water such that the microorganisms present in the process water are reduced by no less than 2-log within four hours.

28. The method of claim 27, wherein the biocide and organic amine combination treats the process water such that the microorganisms present in the process water are reduced by no less than 3-log within four hours.

29. The method of claim 22, wherein, after treating the process water with the biocide, the biocide is initially present within the process water at no less than fifteen parts per million and no greater than fifty parts per million.

30. The method of claim 29, wherein, after treating the process water with the biocide, the polyetheramine is present within the process water at no less than five hundred parts per million and no greater than five thousand parts per million.

31. The method of claim 29, further comprising retreating the process water with the biocide.

32. The method of claim 31, wherein the polyetheramine causes degradation of the biocide in the process water.

33. The method of claim 22, wherein treating the process water with the polyetheramine further comprises treating the process water with the polyetheramine in order to accelerate chemical degradation of the biocide.

34. The method of claim 33, wherein the primary amine accelerates the chemical degradation of the biocide such that the biocide is present within process water at less than fifteen parts per million after forty-eight hours.

35. The method of claim 22, wherein a weight ratio of the methylisothiazolinone to the methylchloroisothiazolinone in the biocide is between 1: 1 and 5:1.

36. The method of claim 35, wherein the weight ratio of the methylisothiazolinone to the methylchloroisothiazolinone in the biocide is about 3:1.

37. The method of claim 22, wherein the process water comprises process water for paints or coatings.

38. The method of claim 37, wherein the process water comprises process water for latex paints.

39. The method of claim 22, wherein the process water comprises no less than seventy percent water by weight of the process water.

40. A method of treating process water substantially as described herein.

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