Methods and compositions for reducing azole and aox corrosion inhibitors

Abstract

This invention relates to methods and compositions for reducing azole and AOX corrosion inhibitors. A method for reducing or eliminating N-heterocyclic compounds, the method providing one or more environmentally friendly chelating agents (EBCs) to an aqueous cooling system having at least one N-heterocyclic compound in the presence of a halogenated or non-halogenated oxidant. A method for reducing or eliminating AOX, the method providing one or more environmentally friendly chelating agents (EBCs) to an aqueous cooling system having at least one AOX-containing substance in the presence of a halogenated biocide.

Description

[0001] This application is a divisional application of patent application No. 201980017981.1, filed on March 1, 2019, entitled "Method and Composition for Reducing Zolpidem and AOX Corrosion Inhibitors". Cross-reference to related applications This application claims priority to U.S. Provisional Patent Application Serial No. 62 / 640,163, filed March 8, 2018. Technical Field

[0002] The present invention relates to methods and compositions for reducing or eliminating N-heterocyclic compounds and / or AOX (adsorbable organohalides), and more specifically, to reducing or eliminating azoles and / or AOX from industrial cooling systems while maintaining adequate corrosion protection. Background Technology

[0003] Industrial systems use water as the medium for heating and cooling applications. These recirculation systems can be closed or open to the environment. Open recirculation cooling systems utilize various features of metal pipes, condensers, and heat exchangers. The metallurgy chosen can vary from very expensive metals (such as titanium) or various types of stainless steel to less expensive metals (such as low-carbon steel) and alloys of various yellow metals (such as copper, ADM, and copper-nickel).

[0004] Water and the various salt ions it contains are naturally corrosive to many types of metallurgy. Chlorides and sulfates, combined with dissolved oxygen, can lead to the formation of generalized or localized corrosion galvanic cells on metal surfaces. In open-circuit cooling systems, water becomes concentrated as it passes through cooling towers, further increasing its corrosivity, as measured by known indices such as the Larson-Scoll index, which correlates corrosion rates with chloride and sulfate concentrations. Due to operating conditions, open-circuit industrial systems can carry and promote microbial growth. These microorganisms can enhance the corrosivity of concentrated water through the formation of biofilms (whose respiratory waste produces chlorides and sulfates) or the treatments required to control their populations.

[0005] A common and cost-effective method for treating microorganisms is the use of oxidizing biocides. Oxidizing biocides can be divided into two categories: halogenated ones (chlorine and bromine types) and non-halogenated ones (chlorine dioxide, inorganic peroxides, organic peroxides, and ozone). Halogenated oxidants react with organic materials or industrial chemical treatment agents to control scaling and corrosion, producing absorbable organohalides (AOX). All oxidants increase the corrosivity of water because they have a sufficiently high oxidation potential to avoid conventional cathodic corrosion reactions with oxygen and accept electrons from base metals, accelerating general and localized corrosion.

[0006] Industrial systems are frequently treated with corrosion inhibitors due to salt concentration, microbial growth, and the use of oxidants. Precipitated salts are a common method in iron-based metallurgy, utilizing molecular and polymeric treatments to achieve specific control over salt supersaturation and inhibition. Typical cathode inhibitor salts used are calcium carbonate and calcium phosphate. Surface films readily form and are controlled by appropriate scale inhibitors. These passivation films are on the micrometer scale and are not considered scale or fouling because they minimally interfere with heat transfer processes. When conditions in the water make calcium carbonate and phosphate insufficient, various metals can be added in low doses to supplement or replace them. Typical metals include various transition metals, p-block metals, and f-block metals: Cr, Mo, W, Ti, Mn, Al, As, Sn, Zn, La, Eu, etc.

[0007] Alternatively, organic-based molecules and polymers characterized by p-block elements have become common corrosion inhibitors in both ferrometallurgical and copper-based metallurgical processes. Those characterized by nitrogen atoms have shown suitability for both ferrometallurgical and copper-based surfaces. Specifically, the molecules or polymers are characterized by nitrogen heterocycles. The industrial standard for treating yellow metal surfaces is the use of substituted azoles, particularly the benzotriazole family.

[0008] Unfortunately, many N-heterocyclic compounds (such as azoles) are characterized by unfavorable biodegradability and toxicity profiles. This can be seen in the benzotriazole family, where (due to the poor biodegradability and molecular stability of these molecules) they escape wastewater treatment processes and bioaccumulate in rivers and lakes. This is further exacerbated by their associated aquatic toxicity profile. There is a need to reduce or eliminate the use of N-heterocyclic compounds as industrial chemical treatment agents to favor “greener” alternatives while providing equivalent or improved corrosion inhibition in iron and copper-based metallurgicals. In the case of copper, the ability to control copper emissions through chelation and precipitation chemical reactions must also be provided.

[0009] A common use of halogenated biocides with residual free halides at concentrations above 0.5 ppm is to minimize risks associated with Legionella, which has also led to increasing concerns about AOX (Average Oxygen sulfide). In industrial systems feeding halogenated biocides, N-heterocyclic substances are prone to in-situ reactions. Halogens added to the N-heterocycle can exist in equilibrium, either as transient substances or permanently covalently linked to the N-heterocycle, increasing the AOX contribution in the industrial system in either manner. Azole inhibitors often encounter problems where benzotriazole or tolyltriazole has been shown to result in inhibitor loss, foul odor, and increased AOX upon chlorination or bromination under industrial cooling conditions. Therefore, AOX substances are inherently toxic, as seen in the flame retardant industry, and increasing health and environmental regulations seek to minimize or reduce AOX levels.

[0010] A common practice to minimize the reactivity of N-heterocycles with halogenated biocides is to incorporate a halogen at a specific site, or to enhance the N-heterocycle by thermodynamically or sterically blocking the in-situ reaction in the new molecule. This non-in-situ approach unfortunately leads to the formation of inherent AOX substances when a halogen is added to the parent molecule, and provides improved corrosion resistance. This was seen in the development of chloro- and bromo-tolyltriazoles.

[0011] There is a need to develop new corrosion control procedures and inhibitors to reduce or eliminate AOX from industrial treatment processes. Therefore, due to the poor biodegradability of N-heterocyclic substances (such as azoles) and the corresponding bioaccumulation of a class of molecules that can have potent toxic distributions, there is a need to reduce or minimize N-heterocyclic substances (such as azoles) from industrial water treatment processes. Similarly, there is a need to reduce or minimize industrial corrosion treatment processes that contribute AOX substances under halogenated oxidation conditions due to the formation of in-situ transient halogenated N-heterocyclic rings or the use of ex-situ halogenated N-heterocyclic rings. Therefore, it is desirable to develop “greener” inhibitors and overall corrosion procedures that achieve the aforementioned results with the same or improved performance. Summary of the Invention

[0012] The disclosed techniques described below are generally used to reduce or eliminate azoles (N-heterocyclic compounds) or AOX from industrial cooling systems.

[0013] According to one aspect of the disclosed technology, a method for reducing or eliminating N-heterocyclic rings is provided. The method includes providing one or more environmentally friendly chelating agents (EBCs) to an aqueous cooling system containing at least one N-heterocyclic ring in the presence of a halogenated or non-halogenated oxidant.

[0014] In some implementations, environmentally friendly chelating agents (EBCs) include (1) aminopolycarboxylic acids, (2) polyamino acids or nucleic acids, (3) buffers, or (4) aminoalkylphosphonic acids and mixtures of their respective hydrolysis products.

[0015] In some embodiments, the aminopolycarboxylic acid comprises a substituted amino acid or a combination thereof having -COOH and / or -PO3. In some embodiments, the aminopolycarboxylic acid contains one or more amino functional groups, wherein the aminopolycarboxylic acid is ethylenediaminetetraacetic acid, N-(2-hydroxyethyl)ethylenediaminetriacetic acid, diethylenetriaminepentaacetic acid, hypozoxytriacetic acid, methylglycine diacetic acid (MGDA), tetrasodium N,N-dicarboxymethyl glutamate, (2R,3R,4S,5R,6R)-3,4,6-trihydroxy-5-sulfonoxyoxane-2-carboxylic acid, or ethylenediamine-N,N'-disuccinic acid. In some embodiments, the polyamino acid is polyaspartic acid or a peptide containing more than one amino acid.

[0016] In some embodiments, the buffer is selected from N-(2-acetamido)-2-aminoethanesulfonic acid, N-(2-acetamido)iminodiacetic acid, adenosine monophosphate, 2-amino-2-methylpropane-1,3-diol, 2-hydroxy-3-[(2-hydroxy-1,1-dimethylethyl)amino]-1-propanesulfonic acid, N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid, N,N-dihydroxyethylglycine (Bicine), Bis-Tris 1,3-Bis(tris(hydroxymethyl)methylamino)propane, calcium alkylbenzene sulfonate, N-cyclohexyl-3-aminopropanesulfonic acid, N-cyclohexyl-2-hydroxy-3-aminopropanesulfonic acid, 2-(cyclohexylamino)ethanesulfonic acid, 3-(bis(2-hydroxyethyl)amino)-2-hydroxypropane-1-sulfonic acid, 3-[4-(2-hydroxyethyl)-1-piperazinyl]propanesulfonic acid, 4-(2-hydroxyethyl)-1-piperazinepropanesulfonic acid, 4-(4-(2-hydroxyethyl))-1-piperazinepropanesulfonic acid Piperazine-1-yl)butane-1-sulfonic acid, 4-(2-hydroxyethyl)-1-piperazine ethanesulfonic acid, 2-hydroxy-3-(4-(2-hydroxyethyl)piperazine-1-yl)propane-1-sulfonic acid, 2-(N-morpholino)ethanesulfonic acid, 4-morpholinobutane-1-sulfonic acid, 3-(N-morpholino)propanesulfonic acid, 3-morpholino-2-hydroxypropanesulfonic acid, piperazine-N,N'-bis(2-ethanesulfonic acid), piperazine-1,4-bis(2-hydroxypropanesulfonic acid), 4-((1 3-Dihydroxy-2-(hydroxymethyl)prop-2-yl)amino)butane-1-sulfonic acid, 3-((1,3-dihydroxy-2-(hydroxymethyl)prop-2-yl)amino)propane-1-sulfonic acid, N-[tris(hydroxymethyl)methyl]-3-amino-2-hydroxypropanesulfonic acid, triethanolamine, N-tris(hydroxymethyl)methyl-2-aminoethanesulfonic acid, tricine, tris(hydroxymethyl)aminomethane or its substituted or functionalized compounds.

[0017] In some embodiments, aminoalkylphosphonic acid is represented by formula (I). Where R1 is -CH2-R3 or -(CH2) y -NR2 or -(CH2) y -NR-(CH2) y -NR2; where R is -(CH2) x -R3; R2 is -(CH2) x R3; and R3 is -PO3 or -OH, wherein R3 is the same or different, and wherein y is between 1 and 4, and x is between 1 and 4.

[0018] In some embodiments, environmentally friendly chelating agents may be used with metal cation salts comprising transition metals, p-block metals, p-block half-metals, SiO2, silicates and metal silicates, lanthanides, and actinides.

[0019] In some embodiments, the at least one N-heterocycle is an azole, cyclic amine, lactam, sulfonamide, pyridine, hydrogen-pyridine, pyridone, pyrazine, pyrimidine, triazine, or aza In some embodiments, the azole is an imidazolidineone, oxazolidineone, hydantoin, urea, oxazolidine, imidazolidine, isoxazolidine, pyrazolidine, pyrrolidine, maleimide, pyrrolidine-2-one, 2-isooxazolidine, 4-isooxazolidine, 2-oxazolidine, 3-oxazolidine, 2-imidazoline, pyrrole, thiazoline, pyrazolidine, 3-pyrazolidine, 3H-pyrazole, imidazoline, pyrazole, 1,2,3-triazole, 1,2,4-triazole, tetrazolidine, pentazoline, oxazole, isoxazole, 1,2,3-oxadiazole, 1,2,4-oxadiazole, furazolidone, 1,3,4-oxadiazole, thiazole, isothiazole, 1,2,4-thiadiazole, 1,2,5-thiadiazole, 1,3,4-thiadiazole, or a substituted or functionalized compound thereof.

[0020] In some embodiments, an environmentally friendly chelating agent (EBC) is added at a concentration greater than that of the at least one N-heterocyclic ring. In some embodiments, the concentration of the at least one N-heterocyclic ring is less than 1.0 ppm. In some embodiments, the method reduces the N-heterocyclic ring content by about 0.1% to 100%. In some embodiments, the non-halogenated oxidant includes ClO2, inorganic peroxides, organic peroxides, or ozone.

[0021] In another aspect of the disclosed technology, a method for reducing or eliminating AOX is provided. The method includes providing one or more environmentally friendly chelating agents (EBCs) to an aqueous cooling system containing at least one AOX-containing substance in the presence of a halogenated biocide.

[0022] In some embodiments, the environmentally friendly chelating agent (EBC) comprises (1) an aminopolycarboxylic acid, (2) a polyamino acid or nucleic acid, (3) a buffer, or (4) an aminoalkylphosphonic acid and a mixture of their respective hydrolysis products.

[0023] In some embodiments, the aminopolycarboxylic acid comprises substituted amino acids or combinations thereof having -COOH and / or -PO3.

[0024] In some embodiments, the aminopolycarboxylic acid comprises one or more amino functional groups, wherein the aminopolycarboxylic acid is ethylenediaminetetraacetic acid, N-(2-hydroxyethyl)ethylenediaminetriacetic acid, diethylenetriaminepentaacetic acid, hypozoxytriacetic acid, methylglycine diacetic acid, tetrasodium N,N-dicarboxymethylglutamate, (2R,3R,4S,5R,6R)-3,4,6-trihydroxy-5-sulfonoxyoxane-2-carboxylic acid, ethylenediamine-N,N'-disuccinic acid, or a substituted or functionalized compound thereof. In some embodiments, the polyamino acid is polyaspartic acid or a peptide comprising more than one amino acid.

[0025] In some embodiments, the buffer is selected from N-(2-acetamido)-2-aminoethanesulfonic acid, N-(2-acetamido)iminodiacetic acid, adenosine monophosphate, 2-amino-2-methylpropane-1,3-diol, 2-hydroxy-3-[(2-hydroxy-1,1-dimethylethyl)amino]-1-propanesulfonic acid, N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid, N,N-dihydroxyethylglycine, Bis-Tris, 1,3 -bis(tris(hydroxymethyl)methylamino)propane, calcium alkylbenzene sulfonate, N-cyclohexyl-3-aminopropanesulfonic acid, N-cyclohexyl-2-hydroxy-3-aminopropanesulfonic acid, 2-(cyclohexylamino)ethanesulfonic acid, 3-(bis(2-hydroxyethyl)amino)-2-hydroxypropane-1-sulfonic acid, 3-[4-(2-hydroxyethyl)-1-piperazinyl]propanesulfonic acid, 4-(2-hydroxyethyl)-1-piperazinepropanesulfonic acid, 4-(4-(2-hydroxyethyl))-1-piperazinepropanesulfonic acid Piperazine-1-yl)butane-1-sulfonic acid, 4-(2-hydroxyethyl)-1-piperazine ethanesulfonic acid, 2-hydroxy-3-(4-(2-hydroxyethyl)piperazine-1-yl)propane-1-sulfonic acid, 2-(N-morpholino)ethanesulfonic acid, 4-morpholinobutane-1-sulfonic acid, 3-(N-morpholino)propanesulfonic acid, 3-morpholino-2-hydroxypropanesulfonic acid, piperazine-N,N'-bis(2-ethanesulfonic acid), piperazine-1,4-bis(2-hydroxypropanesulfonic acid, 4-((1,3-dihydroxy-2-(hydroxymethyl)prop-2-yl)amino)butane-1-sulfonic acid, 3-((1,3-dihydroxy-2-(hydroxymethyl)prop-2-yl)amino)propane-1-sulfonic acid, N-[tris(hydroxymethyl)methyl]-3-amino-2-hydroxypropanesulfonic acid, triethanolamine, N-tris(hydroxymethyl)methyl-2-aminoethanesulfonic acid, tris(hydroxymethyl)aminomethane, or substituted or functionalized compounds thereof.

[0026] In some embodiments, the aminoalkylphosphonic acid is represented by formula (II). Where R4 is -CH2-R6 or -(CH2) y -NR5 or -(CH2) y-NR'-(CH2) y -NR5; R5 is -(CH2) x R6; and R' is -(CH2). x -R6; and R6 is -PO3 or -OH, where R 6 They are the same or different, and where y is between 1 and 4, and x is between 1 and 4.

[0027] In some embodiments, the at least one AOX-containing substance comprises (1) inherently AOX-containing molecules or (2) transiently AOX-containing molecules.

[0028] In some embodiments, the inherently AOX-containing molecule is an inherently AOX azole under halogenated or non-halogenated conditions. In some embodiments, the halogenation conditions provide a halogenated biocide comprising a bleaching agent, chlorine, bromine, stabilized halogen, or haloamine.

[0029] In some embodiments, the method reduces the AOX contribution by 0.1% to 100%. In some embodiments, the environmentally friendly chelating agent can be used with a metal cation salt comprising transition metals, p-block metals, p-block half-metals, SiO2, silicates and metal silicates, lanthanides, and actinides.

[0030] In another aspect of the disclosed technology, compositions are provided for reducing or eliminating N-heterocyclic or AOX rings from aqueous cooling systems. The compositions comprise (i) a dispersant polymer; (ii) a biocide; (iii) a pH adjuster; and (iv) an environmentally friendly chelating agent, wherein the environmentally friendly chelating agent comprises: (1) an aminopolycarboxylic acid, (2) a polyamino acid or nucleic acid, (3) a buffer, or (4) an aminoalkylphosphonic acid and a mixture of the corresponding hydrolysis products.

[0031] In some embodiments, the composition for reducing or eliminating N-heterocyclic rings or AOX from an aqueous cooling system further comprises (vi) a salt inhibitor, a metal inhibitor, or both. In some embodiments, the composition for reducing or eliminating N-heterocyclic rings or AOX from an aqueous cooling system further comprises (vii) at least one N-heterocyclic ring.

[0032] In some embodiments, the at least one N-heterocycle is an azole, cyclic amine, lactam, sulfonamide, pyridine, hydrogen-pyridine, pyridone, pyrazine, pyrimidine, triazine, or aza In some embodiments, the azole is an imidazolidineone, oxazolidineone, hydantoin, urea, oxazolidine, imidazolidine, isoxazolidine, pyrazolidine, pyrrolidine, maleimide, pyrrolidine-2-one, 2-isooxazolidine, 4-isooxazolidine, 2-oxazolidine, 3-oxazolidine, 2-imidazoline, pyrrole, thiazoline, pyrazolidine, 3-pyrazolidine, 3H-pyrazole, imidazoline, pyrazole, 1,2,3-triazole, 1,2,4-triazole, tetrazolidine, pentazoline, oxazole, isoxazole, 1,2,3-oxadiazole, 1,2,4-oxadiazole, furazolidone, 1,3,4-oxadiazole, thiazole, isothiazole, 1,2,4-thiadiazole, 1,2,5-thiadiazole, 1,3,4-thiadiazole, or a substituted or functionalized compound thereof. Detailed Implementation

[0033] The invention will now be described in a detailed description, in which preferred embodiments are described in detail to enable the practice of the invention. Although the invention has been described with reference to these specific preferred embodiments, it should be understood that the invention is not limited to these preferred embodiments. Rather, the invention includes many alternatives, modifications, and equivalents, as will become apparent from the following detailed description.

[0034] This disclosure provides a method for using an environmentally friendly chelating agent (EBC) to bind low levels of azoles (or N-heterocyclic compounds), which allows for the reduction or elimination of N-heterocyclic compounds and / or AOX. In some embodiments, the use of EBC, concentrated industrial water, dispersants, and salt-suppressing polymers provides the necessary surface passivation on iron and copper alloys.

[0035] Phosphonates are a common water treatment technology used in industrial cooling water systems. They can inhibit mineral scaling and help form passivation films on iron and copper alloys. However, many phosphonates can form insoluble salts with calcium or calcium mineral salts, limiting their widespread use in industrial applications. It is known that phosphonates hydrolyze, at least breaking down the -PO3 functional group, which adds o-PO4 (orthophosphate) to large volumes of industrial water. The additional o-PO4 can increase the scaling potential of Ca / PO4 or contribute to the formation of a passivation film. Once the phosphonate reverts to o-PO4, the remaining substance is no longer an effective scale inhibitor.

[0036] Oxidizing biocides (such as HOCl / OCl-, HOBr / OBr-, ClO2, H2O2, O3, etc.) accelerate the hydrolysis of phosphonates, forming degradation products that are no longer effective scale inhibitors. Surprisingly, phosphonate reversion substances have been found to be EBCs, which can be used to reduce or eliminate N-heterocyclic rings and / or AOX from industrial cooling systems. A wide range of phosphonates have been used to form reversion EBCs. Examples of such reversion EBCs include (but are not limited to) hydroxyethylidene-1,1-diphosphonite (HEDP), amino-tris(methylenephosphonate) (AMP), and 1,3-propanediaminotetramethylenephosphonic acid (PDTMP).

[0037] Furthermore, it has been surprisingly found that several classes of environmentally friendly chelating agents (EBCs) exist that can be used under oxidizing conditions to reduce or remove N-heterocyclic compounds (or azoles) or AOX from industrial cooling systems, while simultaneously improving the toxicity or biodegradability profile of the entire cooling process. The decomposition products resulting from phosphonate reversion form complexes that synergistically interact with azoles to provide electrochemical protection, as well as the necessary passivation film in iron and copper metallurgy. Therefore, EBCs allow for the reduction or elimination of azoles. By reducing or eliminating these known industrial contaminants (such as azoles), the disclosed techniques will reduce the contribution of AOX.

[0038] The disclosed techniques are steps toward developing “green” cooling processes by reducing or eliminating these known industrial contaminants (such as azoles). This invention further reduces the contribution of AOX, or the total amount of adsorbable organohalogens (AOX) present. The combination of low levels of azoles and EBC surprisingly provides improved corrosion rates under enhanced oxidizing conditions, which are standard for controlling microbial growth.

[0039] In one aspect of the disclosed technology, a method for reducing or eliminating N-heterocyclic rings is generally provided. The method includes providing one or more environmentally friendly chelating agents (EBCs) to an aqueous cooling system, wherein the aqueous cooling system contains at least one N-heterocyclic ring in the presence of a halogenated or non-halogenated oxidant. An N-heterocyclic ring refers to any cyclic structure containing nitrogen within a ring.

[0040] The aqueous cooling system disclosed herein includes industrial cooling water systems, recirculated water, wastewater, and pre-solid separation cleaning water. In some embodiments, the aqueous system comes into contact with metal surfaces, particularly copper and ferrous metallurgical materials (including their alloys). In some embodiments, alternative surfaces may include plastics, ceramics, or composite materials. In some embodiments, the composite material may be a combination of plastics, ceramics, or inorganic materials (such as carbon-based allotropes).

[0041] Environmentally friendly chelating agents (EBCs) work in conjunction with water, dispersants, and salt-inhibiting polymers present in waterborne cooling systems to allow for the formation of an improved calcium phosphate passivation film on industrial surfaces. The EBCs used in this paper meet Good's essential requirements for buffers, such as buffering capacity, biosafety, inexpensiveness, and the ability to coordinate with metals.

[0042] Environmentally friendly chelating agents (EBCs) may be selected from (1) aminopolycarboxylic acids, (2) polyamino acids or nucleic acids, (3) buffers, or (4) aminoalkylphosphonic acids and mixtures of their respective hydrolysis products.

[0043] In some embodiments, the environmentally friendly chelating agent (EBC) is an aminopolycarboxylic acid. An aminopolycarboxylic acid with the ability to chelate metals is produced by suitably substituting one or more carboxylic acid functional groups into an aminopolycarboxylic acid. Such substitution methods include, but are not limited to, Michel addition, the use of chloroalkylene carboxylic acid derivatives (such as chloroacetic acid), or the conventional use of formaldehyde and sodium cyanide. Alternatively, in some embodiments, the Mannich reaction with formaldehyde and phosphorous acid can be used instead of EBCs that readily react with halogenated biocides.

[0044] In some embodiments, the aminopolycarboxylic acid comprises a substituted amino acid having -COOH and / or -PO3. In some embodiments, the aminopolycarboxylic acid contains one or more amino functional groups, wherein the aminopolycarboxylic acid is ethylenediaminetetraacetic acid, N-(2-hydroxyethyl)ethylenediaminetriacetic acid, diethylenetriaminepentaacetic acid, hypozoxytriacetic acid, methylglycine diacetic acid (MGDA), tetrasodium N,N-dicarboxymethylglutamate, (2R,3R,4S,5R,6R)-3,4,6-trihydroxy-5-sulfonoxyoxane-2-carboxylic acid, or ethylenediamine-N,N'-disuccinic acid.

[0045] In other embodiments, the environmentally friendly chelating agent is a polyamino acid or nucleic acid. The polyamino acid or peptide disclosed herein may comprise homopolymers of amino acid groups, such as polyaspartic acid, or consist of more than one amino acid, such as a peptide that is artificially synthesized and behaves like an aptamer, or is isolated from natural and sustainable sources. In some embodiments, the polynucleic acid consists of various base pairs that form DNA or RNA-type aptamers.

[0046] In other embodiments, the environmentally friendly chelating agent is a buffer, particularly a Good's buffer. In some embodiments, the Good's buffer, or a suitably functionalized Good's buffer, may be selected from the following compound families: morpholine, piperazine, bis(2-hydroxyethyl)amine, TRIS, cyclohexylamino, acetamido, and propanol. It should be understood that suitable functionalization of the Good's buffer includes: addition of alkyl carboxylic acids (similar to the synthetic pathways used to construct aminopolycarboxylic acids), addition of alkyl sulfonic acids, alkyl phosphonic acids, or phosphonic acids, and ring-opening of the functionalized epoxide moiety.

[0047] In some embodiments, appropriately functionalized Goods buffers include, but are not limited to, N-(2-acetamido)-2-aminoethanesulfonic acid (ACES), N-(2-acetamido)iminodiacetic acid (ADA), adenosine monophosphate (AMP), 2-amino-2-methylpropane-1,3-diol (AMPD), 2-hydroxy-3-[(2-hydroxy-1,1-dimethylethyl)amino]-1-propanesulfonic acid (AMPSO), N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid (BES), N,N-dihydroxyethylglycine, and Bis-Tris 1,3-Bis(tris(hydroxymethyl)methylamino)propane (BTP), calcium alkylbenzene sulfonate (CABS), N-cyclohexyl-3-aminopropanesulfonic acid (CAPS), N-cyclohexyl-2-hydroxy-3-aminopropanesulfonic acid (CAPSO), 2-(cyclohexylamino)ethanesulfonic acid (CHES), 3-(bis(2-hydroxyethyl)amino)-2-hydroxypropane-1-sulfonic acid (DIPSO), 3-[4-(2-hydroxyethyl)-1-piperazinyl]propanesulfonic acid (EPPS), 4-(2-hydroxyethyl)-1-piperazinepropanesulfonic acid (HEPPS), 4-(4- (2-Hydroxyethyl)piperazine-1-yl)butane-1-sulfonic acid (HEPBS), (4-(2-hydroxyethyl)-1-piperazine ethanesulfonic acid) (HEPES), 2-hydroxy-3-(4-(2-hydroxyethyl)piperazine-1-yl)propane-1-sulfonic acid (HEPPSO), 2-(N-morpholino)ethanesulfonic acid (MES), 4-morpholinobutane-1-sulfonic acid (MOBS), 3-(N-morpholino)propanesulfonic acid (MOPS), 3-morpholino-2-hydroxypropanesulfonic acid (MOPSO), piperazine-N,N'-bis(2-ethanesulfonic acid) (PIPES), piperazine... Azine-1,4-bis(2-hydroxypropanesulfonic acid) (POPSO), 4-((1,3-dihydroxy-2-(hydroxymethyl)propane-2-yl)amino)butane-1-sulfonic acid (TABS), 3-((1,3-dihydroxy-2-(hydroxymethyl)propane-2-yl)amino)propane-1-sulfonic acid (TAPS), N-[tris(hydroxymethyl)methyl]-3-amino-2-hydroxypropanesulfonic acid (TAPSO), triethanolamine (TEA), N-tris(hydroxymethyl)methyl-2-aminoethanesulfonic acid (TES), tris(hydroxymethyl)aminomethane (Tris).

[0048] In other embodiments, the environmentally friendly chelating agent (EBC) is an aminoalkylphosphonic acid, or a mixture of aminoalkylphosphonic acids and their respective hydrolysis products. In some embodiments, these aminoalkylphosphonic acids are represented by formula (I). Where R1 is -CH2-R3 or -(CH2) y -NR2 or -(CH2) y-NR-(CH2) y -NR2; R2 is -(CH2) x R3; R stands for -(CH2) x -R3; and R3 is -PO3 or -OH, wherein R3 may be the same or different, and wherein both x and y contain one to four carbon atoms. These aminoalkylphosphonic acids are mixed with hydrolysates comprising at least one or more H2-N-R1, H2-NR, R-NH-R1, R-NH-R, wherein R is -(CH2). x -R3, and R1 is -CH2-R3, -(CH2) y -NR2 or -(CH2) y -NR-(CH2) y -NR2, and R2 is -(CH2). x R3; where x and y each contain one to four carbon atoms.

[0049] In some embodiments, the environmentally friendly chelating agent may be used with a metal cation salt comprising Ti, Mo, Mn, W, Zn, Al, SiO2, As, Sn, La, Eu, or combinations thereof.

[0050] In some embodiments, the environmentally friendly chelating agent (EBC) is added at a concentration greater than the N-heterocyclic concentration. In some embodiments, the N-heterocyclic concentration is less than 1.0 ppm. In other embodiments, the N-heterocyclic concentration is less than 0.5 ppm, and in still other embodiments, the N-heterocyclic concentration is less than 0.25 ppm.

[0051] In some embodiments, the method of the present invention reduces the N-heterocyclic content by about 0.1% to 100%. In other embodiments, the N-heterocyclic content is reduced by about 10-90%, in other embodiments by about 25-75%, and in other embodiments by about 40-60%.

[0052] In some embodiments, the N-heterocycle is an azole. An azole is a five-membered heterocyclic compound containing a nitrogen atom. Those skilled in the art will understand that the azoles of this technology can include any type of substituted or functionalized azole molecules.

[0053] In some embodiments, the N-heterocycle is an azole, which is an imidazolidinone, oxazolidinone, hydantoin, urea, oxazolidinone, imidazolidinone, isoxazolidinone, pyrazolidine, pyrrolidine, maleimide, pyrrolidine-2-one, 2-isooxazolidine, 4-isooxazolidine, 2-oxazolidine, 3-oxazolidine, 2-imidazolidinone, pyrrole, thiazoline, pyrazolidine, 3-pyrazolidine, 3H-pyrazole, imidazoline, pyrazole, 1,2,3-triazole, 1,2,4-triazole, tetraazole, pentaazole, oxazole, isoxazole, 1,2,3-oxadiazole, 1,2,4-oxadiazole, furazolidone, 1,3,4-oxadiazole, thiazole, isothiazole, 1,2,4-thiadiazole, 1,2,5-thiadiazole, 1,3,4-thiadiazole, or any substituted or functionalized compound thereof.

[0054] In other embodiments, the N-heterocycle is a lactam, sulfonamide, pyridine, hydrogen-pyridine, pyridone, pyrazine, pyrimidine, triazine, or aza. .

[0055] In some embodiments, the environmentally friendly chelating agent (EBC) is added at a concentration greater than that of the azole. In some embodiments, the concentration of the azole is less than 1.0 ppm. In other embodiments, the concentration of the azole is less than 0.5 ppm, and in still other embodiments, the concentration of the azole is less than 0.25 ppm.

[0056] In some embodiments, the method of the present invention reduces the azole content by about 0.1% to 100%. In other embodiments, the azole content is reduced by about 10-90%, in other embodiments by about 25-75%, and in other embodiments by about 40-60%.

[0057] In some embodiments, the invention includes an oxidation treatment or an oxidant. Oxidants can counteract the ability of azoles to form a passivation film. The method of the present invention reduces the concentration of azoles in industrial cooling systems to below 1.0 ppm, resulting in minimal passivation film formation by calcium phosphate, thus avoiding competition for surface between azoles and salts. The low levels of azoles, combined with the added EBC, provide the necessary electrochemical corrosion protection, thereby leading to a reduction in azoles (and AOX) while maintaining and improving performance at increased oxidation levels used for microbial control.

[0058] In some embodiments, the oxidant may be selected from sodium hypochlorite (bleach) or hypochlorous acid, sodium hypobromite or hypobromous acid, stabilized bromine, peroxides (inorganic peroxides, such as H₂O₂, and organic peroxides, such as peracetic acid), and ozone. In some embodiments, these oxidants are added directly to the aqueous phase. In some embodiments, the oxidant may be halogenated or non-halogenated. Halogenated oxidants have the ability to add halogens to organic molecules or polymers.

[0059] In some embodiments, a non-halogenated oxidant is provided. In some embodiments, the non-halogenated oxidant includes ClO2, peroxide, or ozone.

[0060] In another aspect of this disclosure, a method for reducing or eliminating AOX is provided. The method includes providing one or more environmentally friendly chelating agents (EBCs) to an aqueous cooling system, wherein the aqueous cooling system contains at least one AOX-containing substance in the presence of a halogenated biocide or oxidant.

[0061] Adsorbable organohalogens, or AOX, can be characterized as any organic substance having halogen atoms covalently linked to the parent structure, thus enabling adsorption onto the substrate. When used with certain oxidants such as halogenated oxidants (e.g., bleaching agents or bromine), azoles can have inherently adsorbable organohalides (AOX) or transient AOX in industrial cooling systems. Molecules or polymers containing halogens in their molecular backbone or polymer backbone are inherently AOX substances.

[0062] In some embodiments, the method of the present invention provides at least one AOX-containing substance, said AOX-containing substance comprising (1) intrinsically AOX-containing molecules, or (2) transiently AOX-containing molecules.

[0063] In some embodiments, an inherent or inherently AOX-containing substance is provided, characterized by the non-in-situ and external covalent addition of halogen to the parent structure in an industrial water stream. The inherent AOX substance can be produced at a significant concentration using a mixing tank or mechanical device, having incorporated sufficient halogenating agent on-site in the industrial system and immediately prior to addition to the industrial water stream.

[0064] Examples of inherently AOX-containing molecules include, but are not limited to, chlorobenzotriazole, bromobenzotriazole, chloro-tolyltriazole, bromo-tolyltriazole, 5-chloro-1-phenyl-1H-tetrazole, or 5-(4-chlorophenyl)-1H-tetrazole. In some embodiments, the inherently AOX-containing molecule is an inherently AOX azole under halogenated or non-halogenated conditions.

[0065] In some embodiments, transient AOX substances are formed, wherein covalent halogen bonds are provided in situ in the industrial water stream due to the presence of reactive organic matter and halogenated oxidizing biocide. The transient AOX substances will exist in equilibrium between the parent molecule and the halogenated transient AOX product. In some embodiments, the inherent AOX substance can react in situ with a chlorinating or brominizing oxidizing agent to form a transient AOX substance existing in equilibrium, wherein at least 0.1% of the molar concentration of the azole is present as AOX. Therefore, at any given time in the industrial stream, a certain proportion of the organic matter is always present as transient AOX.

[0066] In some embodiments, the AOX-containing substance comprises transiently AOX-containing molecules. Examples of transiently AOX-containing molecules include, but are not limited to, 1-N-chlorobenzotriazole, 1-N-chloro-tolyltriazole, 1-N-chloro-chlorotolyltriazole, 1-N-bromobenzotriazole, 1-N-bromo-tolyltriazole, or 5-phenyl-1N-chlorotetrazole.

[0067] In some embodiments, the disclosed method reduces AOX contribution by 0.1% to 100%. In other embodiments, the disclosed method reduces AOX contribution by at least 75%, and in still other embodiments, by at least 50%.

[0068] In some implementations, halogenated biocides are used. In some implementations, halogenated biocides include bleach, chlorine, or bromine.

[0069] In another aspect of the disclosed technology, compositions are provided for reducing or eliminating azoles or AOX from aqueous cooling systems. In some embodiments, the composition comprises (i) a dispersant polymer; (ii) a salt inhibitor; (iii) a biocide; (iv) a pH adjuster; (v) an EBC; (vi) a metal inhibitor; and (vii) an N-heterocyclic compound. In other embodiments, the composition comprises (i) a dispersant polymer; (ii) a salt inhibitor; (iii) a biocide; (iv) a pH adjuster; (v) an EBC; (vi) a metal inhibitor; and / or (vii) an N-heterocyclic compound.

[0070] In some implementations, salt inhibitors and pH adjusters are added as needed to inhibit scaling or corrosion. In some implementations, metal inhibitors are included when a target pH set point is specified. However, in some industrial water applications, a pH set point is not targeted, and the pH of the water can be determined based on its natural pH target based on water properties and buffering capacity.

[0071] In some implementations, the treated industrial water stream consists of mineral cations and anions. A typical characteristic cation is Ca. 2+ and Mg 2+ Its concentration ranges from 0 ppm to 10,000 ppm. A typical characteristic anion is Cl... - SO4 2- PO4 3- HCO3 - and CO3 2- The composition, with concentrations ranging from 0 ppm to 100,000 ppm, is also present. Group 1 cations can also be found, and they generally contribute to the overall charge balance of the aqueous matrix. Various forms of silicates and silica can characterize water flow, with concentrations ranging from 0 ppm to 1000 ppm.

[0072] In some embodiments, industrial water streams can be treated with metal cations to improve corrosion control. In some embodiments, the metal cation salt comprises transition metals, p-block metals, p-block half-metals, SiO2, silicates and metal silicates, lanthanides, and actinides. In some embodiments, the metal cation salts that can be added include, but are not limited to, Ti, Mo, Mn, W, Zn, Al, silica (SiO2), As, Sn, La, and Eu. These can be added as cationic metal salts at concentrations from 0 ppm to 100 ppm.

[0073] In some implementations, salt inhibitors or scale inhibitors may be added to the water flow. Salt inhibitors are typically polycarboxylic acid molecules or low molecular weight polymers (<10,000 MW). Phosphonates have also traditionally been used as salt inhibitors and scale inhibitors. Salt inhibitors are added to the water flow when a particular salt is supersaturated, where the calculated SI is greater than 1. Concentrations of salt inhibitors ranging from 0 ppm to 100 ppm can be added.

[0074] In some embodiments, a polymeric dispersant and / or salt inhibitor is added to the water flow. In some embodiments, the polymeric dispersant and / or salt inhibitor is a polycarboxylic acid polymer, wherein at least one additional monomer consists of a sulfonic acid group. The dispersant monomer suspends supersaturated salts, suspended solids, and metal oxide colloids in the solution and prevents scale or fouling on metal surfaces.

[0075] In some embodiments, biocides are fed into industrial systems that enhance the microenvironment for microbial species. In some embodiments, the biocides can be oxidative or non-oxidative. Additionally, biodispersants can be added together with the biocides. In some embodiments, the biodispersant can be anionic, cationic, or nonionic surfactants.

[0076] In some implementations, a pH adjuster / substance is added to the water flow. The pH adjuster / substance contains any salt, inorganic, or organic substance that allows the pH to change to a target set point. Examples include, but are not limited to, sulfuric acid, hydrochloric acid, sodium hydroxide, caustic soda, sodium bicarbonate, CO2, and citric acid.

[0077] experiment Tables 1 and 2 provide experimental results of the method of the present invention, which provides halogenation stabilization and good corrosion resistance.

[0078] A recirculation test bench was provided. The test bench has a total volume of approximately 1.4 L and is equipped with a water pump, a bypass support for corrosion samples and probes, a resin-glass encapsulated heat exchanger, and probes for controlling pH and ORP. The water chemistry is described below. The heat exchanger is equipped with an electric heater (0-11,000 BTU / ft² / hr) and a flow meter (0-4.6 ft / sec) to control the heat load. The corrosion rate was monitored using a Corrator meter mounted on the bypass support. The weight loss corrosion rate was calculated by inserting the sample into the bypass support for a test period of 7-8 days. pH was controlled using sulfuric acid dripping. The oxidation-reduction potential (ORP) was controlled at the desired free residual chlorine (FRC) level, determined using the Hach Powder Pack method. The water flow rate was maintained at approximately 4 ft / sec, and the bulk water temperature was controlled at 120℉.

[0079] Table 1 As shown in Table 1, the water characteristics are: 600 ppm Ca (calculated as CaCO3), 300 ppm Mg (calculated as CaCO3), 50 ppm M-alkalinity (calculated as CaCO3), 3 ppm p-PO4 (calculated as PO4), 485 ppm Cl. - 285ppm SO4 2- pH = 7.2; ADM-C and LCS-C refer to the average weight loss of the sample; ADM-P and LCS-P refer to the average instantaneous corrosion rate over the entire test duration; AOX refers to the inherent AOX concentration; bleach is a measure of residual free chlorine determined by the Hach Powder Pack test. Dispersant polymers, excluding N-heterocyclic compounds and EBCs, are added to the aqueous system to maintain a concentration of 6 ppm. Chemical dosage is based on active ingredient percentage. a The sample exhibits significant dezincification areas. b The test run measured a Δ > 0.1 ppm between the (total chlorine - residual chlorine) powder test results from Hach.

[0080] Table 1 presents exemplary data on the reduction or elimination of N-heterocyclic compounds and AOX under neutral industrial conditions. Runs 1 and 2 in Table 1 represent typical cooling procedures utilizing N-heterocyclic chlorotoluenetriazole, differing only in the ppm of residual free chlorine. Increased free chlorine leads to a more corrosive environment, as seen in the increased corrosion rate of the samples in Run 2. In Run 2, dezincification or dealloying of copper metallurgy was also observed, not fully represented by the corrosion rate figures. Longer trials will ultimately result in much higher corrosion rates.

[0081] The EBC in runs 4, 5, and 8 demonstrated its ability to reduce the N-heterocyclic content from 2 ppm to 0.5 ppm and the intrinsic AOX from 500 ppb to 100 ppb. The o-PO4 concentration increased by 2 ppm due to the reversion of phosphonates. A control run 3 was conducted to show that, in the absence of EBC, increasing the o-PO4 concentration by 2 ppm resulted in a significantly higher corrosion rate for the LCS sample. Runs 4 and 5 also showed that not all phosphonates performed equally well; for both ADM and LCS samples relative to control run 2, run 4 outperformed run 5. The combination of EBC and hydrolysis products in run 4 was superior in passivating the metal surface and chelating soluble copper for electrochemical protection.

[0082] Compared to controls 1 and 2, all examples in Table 1 effectively protected copper and copper alloy surfaces. Operations 9 through 12 all showed significant Δ values ​​for total chlorine versus residual free chlorine, indicating that EBCs are susceptible to some halogenated forms from halogenated oxidants and bleaching agents. These EBCs are better suited for systems with non-halogenated oxidants, or can be appropriately functionalized with alkylene carboxylic acids or phosphonates.

[0083] Examples of chelating agents, 13-14, exhibit a considerable binding constant for copper. Despite this property, they are less effective than other EBCs in protecting metal surfaces. EBCs are not selected solely based on the metal binding constant and are effective in maintaining performance while reducing N-heterocyclic rings and / or AOX.

[0084] Table 2 provides exemplary examples of the use of EBC under alkaline industrial cooling conditions. Run 3 demonstrates the ability of EBC to reduce N-heterocyclic (azole) and AOX in test water. Run 4 confirms the ability of EBC to reduce only N-heterocyclic (azole) compounds in industrial water. EBC GLADMP is also an example of how the amino acid glycine can be substituted with a suitable functional group that imparts halogen stability and activity as an EBC. The amine functional group of glycine reacts with 2 equivalents of chloroacetic acid (see exemplary procedure).

[0085] Table 2 provides results in an alkaline industrial water system. In Table 2, Run 4 provides an example of reducing transient AOX using EBC. Published literature estimates that tolyltriazole forms approximately 10% of the transient 1-N-chloro-tolyltriazole. Using standard methods for measuring AOX, tolyltriazole (3 ppm sample) and benzotriazole (1.5 ppm sample) have been found to contribute 97 μg Cl / L and 46 μg Cl / L, respectively. Therefore, in addition to reducing the azole concentration, Run 4 was able to reduce transient AOX from 97 μg Cl / L to a possible 16 μg Cl / L.

[0086] Table 2 As shown in Table 2, the water characteristics are: 400 ppm Ca (calculated as CaCO3), 150 ppm Mg (calculated as CaCO3), 200 ppm M-alkalinity (calculated as CaCO3), and ppm Cl. - ppm SO4 2- pH = 8.6; ADM-C and LCS-C refer to the average weight loss of the sample; ADM-P and LCS-P refer to the average instantaneous corrosion rate over the entire test duration; AOX refers to the inherent AOX concentration; bleach is a measure of residual free chlorine as determined by the Hach Powder Pack test. Dispersant polymers, excluding N-heterocyclic compounds and EBC, are added to the aqueous system to maintain a concentration of 8 ppm. An additional 8 ppm of salt inhibitor is added for scale control. Chemical dosage is based on active ingredient percentage.

[0087] The synthesis of GLADMP as shown in Table 2 (or the synthesis using bis(phosphonomethyl)glycine reacting with phosphorous acid in a Mannich-type manner) was carried out as follows: 46.62 g (0.56 mol) of phosphorous acid was dissolved in 55.00 mL of deionized water in a four-necked flask equipped with a thermometer, stirrer, condenser, and feed line. Next, 21.07 g (0.28 mol) of glycine and 27.59 g (0.28 mol) of 37% HCl were added to the flask, and the mixture was heated to reflux at 105 °C. Once under reflux, 53.57 g (0.66 mol, 20% excess) of 37% formaldehyde was added over a 1-hour period. After the addition was complete, the solution was kept under reflux for 3 hours and then cooled to 25 °C. The pH of the solution was adjusted from 0.64 to 5.24 by adding 91.42 g (1.14 mol) of 50% caustic soda. The product solution had a mass of 288.19 g and a solid content of 39.73%.

[0088] This written description uses examples to disclose the invention, including the best mode, and enables those skilled in the art to practice the invention, including making and using any device or system and performing any combined methods. The patentable scope of the invention is defined by the claims, and may include other embodiments that would occur to those skilled in the art. Such other embodiments are intended to be within the scope of the claims if they have structural elements that are not different from the literal language of the claims, or if they include equivalent structural elements that are not substantially different from the literal language of the claims.

Claims

1. The use of an inhibitor composition for providing corrosion protection to yellow metallic surfaces in contact with a water-based cooling system, said composition comprising: (i) Dispersant polymers; (ii) Biocides; (iii) pH adjusting substances; as well as (iv) An environmentally friendly chelating agent, wherein the environmentally friendly chelating agent comprises: (1) Amino polycarboxylic acids, (2) Polyamino acids, (3) A buffer, wherein the buffer is selected from N-(2-acetamido)-2-aminoethanesulfonic acid, N-(2-acetamido)iminodiacetic acid, 2-amino-2-methylpropane-1,3-diol, 2-hydroxy-3-[(2-hydroxy-1,1-dimethylethyl)amino]-1-propanesulfonic acid, N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid, N,N-dihydroxyethylglycine, Bis-Tris, 1,3-bis(tris(hydroxymethyl)methylamino)propane, calcium alkylbenzenesulfonate, N-cyclohexyl-3-aminopropanesulfonic acid, N-cyclohexyl-2-hydroxy-3-amino 2-(cyclohexylamino)ethanesulfonic acid, 3-(bis(2-hydroxyethyl)amino)-2-hydroxypropane-1-sulfonic acid, 4-((1,3-dihydroxy-2-(hydroxymethyl)prop-2-yl)amino)butane-1-sulfonic acid, 3-((1,3-dihydroxy-2-(hydroxymethyl)prop-2-yl)amino)propane-1-sulfonic acid, N-[tris(hydroxymethyl)methyl]-3-amino-2-hydroxypropanesulfonic acid, triethanolamine, N-tris(hydroxymethyl)methyl-2-aminoethanesulfonic acid, tris(hydroxymethyl)aminomethane, tris(hydroxymethyl)aminomethane, or their substituted or functionalized compounds, or (4) A mixture of aminoalkylphosphonic acid and the corresponding hydrolysis product, and The composition described herein does not contain N-heterocyclic rings.

2. The use according to claim 1, wherein the composition further comprises (vi) a salt inhibitor, a metal inhibitor, or both.

3. The use according to claim 1, wherein the aminopolycarboxylic acid comprises a substituted amino acid or a combination thereof having -COOH and / or -PO3.

4. The use according to claim 1, wherein the aminopolycarboxylic acid comprises one or more amino functional groups, wherein the aminopolycarboxylic acid is ethylenediaminetetraacetic acid, N-(2-hydroxyethyl)ethylenediaminetriacetic acid, diethylenetriaminepentaacetic acid, hypozoxytriacetic acid, methylglycine diacetic acid (MGDA), tetrasodium N,N-dicarboxymethylglutamate, (2R,3R,4S,5R,6R)-3,4,6-trihydroxy-5-sulfonoxyoxane-2-carboxylic acid, or ethylenediamine-N,N'-disuccinic acid.

5. The use according to claim 1, wherein the polyamino acid is polyaspartic acid or a peptide containing more than one amino acid.

6. The use according to claim 1, wherein the aminoalkylphosphonic acid is represented by formula (I). ， Where R1 is -CH2-R3 or -(CH2) y -NR2 or -(CH2) y -NR-(CH2) y -NR2; where R is -(CH2) x -R3; R2 is -(CH2) x R3; and R3 is -PO3 or -OH, wherein R3 is the same or different, and wherein y is between 1 and 4, and x is between 1 and 4.

7. The use according to claim 1, wherein the environmentally friendly chelating agent is used in conjunction with a metal cation salt comprising transition metals, p-block metals, p-block half-metals, SiO2, silicates and metal silicates, lanthanides and actinides.

8. The use according to claim 1, wherein the biocide is selected from ClO2, inorganic peroxides, organic peroxides, ozone, bleaching agents, chlorine, bromine, stabilized halogens or haloamines.

9. A method for inhibiting corrosion on a yellow metallic surface in contact with a water-based cooling system, the method eliminating the use of N-heterocyclic rings, the method comprising adding an inhibitor composition to the water-based cooling system, wherein the inhibitor composition comprises: (i) Dispersant polymers; (ii) Biocides; (iii) pH-regulating substances; and (iv) a chelating agent, wherein the chelating agent comprises: (1) Amino polycarboxylic acids, (2) Polyamino acids, (3) A buffer, wherein the buffer is selected from N-(2-acetamido)-2-aminoethanesulfonic acid, N-(2-acetamido)iminodiacetic acid, 2-amino-2-methylpropane-1,3-diol, 2-hydroxy-3-[(2-hydroxy-1,1-dimethylethyl)amino]-1-propanesulfonic acid, N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid, N,N-dihydroxyethylglycine, Bis-Tris, 1,3-bis(tris(hydroxymethyl)methylamino)propane, calcium alkylbenzenesulfonate, N-cyclohexyl-3-aminopropanesulfonic acid, N-cyclohexyl-2-hydroxy-3-amino 2-(cyclohexylamino)ethanesulfonic acid, 3-(bis(2-hydroxyethyl)amino)-2-hydroxypropane-1-sulfonic acid, 4-((1,3-dihydroxy-2-(hydroxymethyl)prop-2-yl)amino)butane-1-sulfonic acid, 3-((1,3-dihydroxy-2-(hydroxymethyl)prop-2-yl)amino)propane-1-sulfonic acid, N-[tris(hydroxymethyl)methyl]-3-amino-2-hydroxypropanesulfonic acid, triethanolamine, N-tris(hydroxymethyl)methyl-2-aminoethanesulfonic acid, tris(hydroxymethyl)aminomethane, tris(hydroxymethyl)aminomethane, or their substituted or functionalized compounds, or (4) A mixture of aminoalkylphosphonic acid and the corresponding hydrolysis product, and The composition described herein does not contain N-heterocyclic rings.

10. The method of claim 9, wherein the yellow metal comprises copper, ADM, and copper-nickel.

11. The method of claim 9, wherein the aminopolycarboxylic acid comprises a substituted amino acid or a combination thereof having -COOH and / or -PO3.

12. The method according to claim 9, wherein the aminopolycarboxylic acid comprises one or more amino functional groups, wherein the aminopolycarboxylic acid is ethylenediaminetetraacetic acid, N-(2-hydroxyethyl)ethylenediaminetriacetic acid, diethylenetriaminepentaacetic acid, hypozoxytriacetic acid, methylglycine diacetic acid (MGDA), tetrasodium N,N-dicarboxymethylglutamate, (2R,3R,4S,5R,6R)-3,4,6-trihydroxy-5-sulfonoxyoxane-2-carboxylic acid, or ethylenediamine-N,N'-disuccinic acid.

13. The method of claim 9, wherein the polyamino acid is polyaspartic acid or a peptide containing more than one amino acid.

14. The method according to claim 9, wherein the aminoalkylphosphonic acid is represented by formula (I). ， Where R1 is -CH2-R3 or -(CH2) y -NR2 or -(CH2) y -NR-(CH2) y -NR2; where R is -(CH2) x -R3; R2 is -(CH2) x R3; and R3 is -PO3 or -OH, wherein R3 is the same or different, and wherein y is between 1 and 4, and x is between 1 and 4.

15. The method of claim 9, wherein the environmentally friendly chelating agent is used in conjunction with a metal cation salt comprising transition metals, p-block metals, p-block half-metals, SiO2, silicates and metal silicates, lanthanides and actinides.

16. The method according to claim 9, wherein the biocide is selected from ClO2, inorganic peroxides, organic peroxides, ozone, bleaching agents, chlorine, bromine, stabilized halogens, or haloamines.

17. A corrosion-inhibiting composition for use in a water-based cooling system, said composition comprising: (i) Dispersant polymers; (ii) Biocides; (iii) pH adjusting substances, wherein the pH adjusting substances are selected from: sulfuric acid, hydrochloric acid, caustic alkali, sodium bicarbonate, CO2 and citric acid; (iv) a chelating agent comprising an aminoalkylphosphonic acid and a mixture of the corresponding hydrolysis product; and (v) at least one N-heterocyclic ring, The concentration of the chelating agent is greater than the concentration of the at least one N-heterocycle.

18. The corrosion-inhibiting composition for a water-based cooling system according to claim 17, wherein the caustic alkali is sodium hydroxide.

19. A method for inhibiting corrosion on a metal surface in contact with a water-based cooling system, wherein the method uses reduced levels of N-heterocyclic compounds, the method comprising adding a corrosion-inhibiting composition to the water-based cooling system, wherein the corrosion-inhibiting composition comprises: (i) Dispersant polymers; (ii) Biocides; (iii) pH adjusting substances; (iv) a chelating agent comprising an aminoalkylphosphonic acid and a mixture of the corresponding hydrolysis product; and (v) at least one N-heterocyclic ring, The concentration of the chelating agent is greater than the concentration of the at least one N-heterocycle.

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