KR20010066172A - Method and composition treating water for inhibiting growth of microorganism and corrosion - Google Patents

Abstract

PURPOSE: A water treatment agent composition for inhibiting corrosion and microorganism is provided, which can inhibit corrosion by 10-60 times than existing corrosion inhibitors by inhibiting anode-cathode reaction, electrochemical reaction that occurs on the surface of metal and also exhibits microorganism sterilizing effects of 10¬4 to 10¬8 than that of existing compositions. CONSTITUTION: The composition comprises 0.05-14% of isothiazolinon of chemical formula 1, wherein R is hydrogen or chlorine, 0.5-50% (based on orthophosphate ion) of phosphate, 0.05-20% (based on zinc ion) of zinc salt selected from zinc chloride, zinc sulfate and zinc nitrate and 0.1-50% (based on phosphonate ion) of phosphonate selected from phosphono butane tricarboxylic acid, hydroxy ethylene diphosphonic acid, hydroxy phosphono carboxylic acid, amino trimethylene phosphonic acid and ethylene diamine tetramethylidine phosphonic acid.

Description

Corrosion and microbial water treatment composition and its method {Method and composition treating water for inhibiting growth of microorganism and corrosion}

The present invention relates to a water treatment agent composition for simultaneously suppressing corrosion and microbial slime formation which may occur in an open-circulating cooling water system. More particularly, the present invention relates to a basic phosphate, phosphonate and zinc. A novel water treatment composition comprising a salt.

In general, corrosion is an extremely normal natural phenomena which attempts to return to the oxide state, which is the natural state of metal through redox reaction of metal and aqueous solution. Corrosion occurs by forming positive and negative electrodes.

Microbial slime refers to a phenomenon in which microorganisms contained in water or microorganisms in the atmosphere are introduced into an open circulation cooling system and attached to a filter and a water pipe of a cooling tower.

In fact, it is easy to find corrosion and microbial slime in various industrial facilities, including cooling towers installed in industrial sites. Corrosion and slime generation shorten the lifespan of facilities and cause environmental pollution, causing huge economic losses.

Conventionally, in order to suppress corrosion and microbial slime generation, since the corrosion inhibitor and the microbial inhibitor were separately put into the open circulation cooling system, the work was inconvenient, and the effect was insignificant.

In the 1960s, a technique using chromium salts was widely used as the water treatment agent composition. However, chromium salts cause environmental pollution by heavy metals and are highly toxic to humans. Recently, examples using phosphates, azole compounds, acrylic polymers, maleic polymers, lignin, tannin, and the like have been published, and are widely used in industrial fields. For example, U.S. Patent No. 4,149,969 discloses compositions containing zinc salts, molybdates, manganese salts, nickel salts, azole compounds, phosphonates, and U.S. Patent Nos. 4,411,865 disclose zinc salts, chromium salts, Cooling water treatment technology using a phosphate, acrylate copolymer has been reported, US Pat. No. 5,156,665 has reported a microbial prevention treatment technology.

However, as mentioned above, these conventional water treatment composition cannot inhibit corrosion and microbial slime at the same time, there was a problem that can not have a satisfactory performance in terms of corrosion and environmental pollution by microorganisms.

The present invention has been made to solve the above problems, an object of the present invention to solve the problems associated with corrosion and microorganisms at the same time and to provide a water treatment agent composition easy to use in open-circulation cooling system.

In order to achieve the above object, the present invention is a corrosion and slime of a metal comprising a) 3-isothiazolinone represented by the following formula (1), b) phosphate, c) zinc salt and d) phosphonate Provided is an inhibitory water treatment composition.

[Formula 1]

In Formula 1, R is hydrogen or chlorine.

Hereinafter, the present invention will be described in detail.

In the water treatment agent composition, 3-isothiazolinone represented by Chemical Formula 1 of a) contains 0.05 to 14%, and in Formula 1, 2-methyl-4-isothiazolone- wherein R is hydrogen. Preference is given to 5-chloro-2-methyl-4-isothiazolone-3one, wherein tri- or R is chlorine, 2-methyl-4-isothiazolone-3-one and 5-chloro-2-methyl-4- More preferably, isothiazolone-3one is mixed in a weight ratio of 1:20 to 20: 1. 3-isothiazolinone of a) is effective against a wide range of microorganisms, and also excellent in sustainability. If it contains less than 0.05%, the sterilization effect is lowered when a certain amount is added, so a large amount should be applied. If it contains more than 14%, the sterilization effect is excellent, but it impairs the storage stability of the product and is not economical.

It is preferable to use 0.5 to 50% of the phosphate of b) based on ortho phosphate, and phosphoric acid, sodium monophosphate, sodium diphosphate, sodium triphosphate, potassium monophosphate, potassium diphosphate or potassium triphosphate may be used. have.

The zinc salt of c) is contained 0.05 to 20% based on the zinc ion, zinc chloride, zinc sulfate, zinc nitrate and the like can be used.

The phosphonate of d) is contained in an amount of 0.1 to 50% on the basis of organic phosphate ions, hydroxy ethyline diphosphonic acid, phosphonobutane tricarboxylic acid, hydroxy phosphono carboxylic acid, amino trimethylene Phosphoric acid or ethylene diamine tetra methyllidine phosphonic acid and the like can be used. The use of 0.1% or less is ineffective and should be used in excess, and the use of 50% or more is not economical. The water treatment composition of the present invention is characterized in that it contains 3-isothiazolinone, phosphate, zinc salt, phosphonate, excellent bactericidal effect against all microorganisms, anodization which is an electrochemical reaction occurring on the metal surface Excellent anticorrosive effect can be expected by suppressing the cathodic reaction and minimizing the conditions that can cause corrosion. Therefore, the water treatment agent composition of the present invention containing all of the above components can be used in open circulation cooling systems and daily cooling systems to prevent corrosion that can occur in various industrial water pipes, and effectively inhibit the growth of microorganisms.

The present invention will be described in detail through the following examples and comparative examples. However, these Examples are for illustrating the present invention, and the present invention is not limited to these.

(Example)

Examples 1-5

After maintaining the respective concentrations of the water treatment agent components shown in Table 2 in the test water shown in Table 1, after adding water to make 100% by weight, the weight of the carbon steel by the following corrosion and microbial inhibition test The corrosion rate (mdd, mg / (dm ² ㆍ day)) and the microbial reduction concentration according to the weight loss are described in Table 4.

(Corrosion and Microbial Suppression Test Method)

Rotating corrosion tester was used at 30 ℃, 170rpm, 10ml / min air injection. A mixture of pneumoniae ATCC 1560, Staphylococcus edidermis ATCC 155, Staphylococcus aureus ATCC 6538, and 8 species of Bac.

At this time, after maintaining each concentration of the water treatment agent components shown in Table 2 in the test water quality of Table 1, the corrosion rate (mdd, mg / (dm ² ㆍ day) and the results of microbial reduction according to the weight loss of carbon steel is shown in Table 4 It was.

Table 1 Test Solution Water Quality Conditions

Water quality # One # 2 # 3 # 4 # 5 pH 8.5 8.2 8.0 7.8 7.6 Ca-H (ppm) 50 100 200 300 400 Mg-H (ppm) 10 20 40 60 80 Chloride (ppm) 40 80 160 240 320 Initial Microbial Concentration (CFU / ml) 10 ⁷ 10 ⁷ 10 ⁷ 10 ⁷ 10 ⁷

pH was adjusted with 0.1 N aqueous sodium hydroxide solution and 0.05 N sulfuric acid solution.

Ca-H represents calcium hardness and was adjusted with calcium chloride.

Mg-H was adjusted to magnesium sulfate by magnesium hardness.

The initial microbial concentration was adjusted to the initial microbial concentration after the preparation of ⁸ microbial mixtures 10 ⁸ CFU / ml. Where CFU is the Cell Forming Unit.

Table 2 Composition of Water Treatment Agent of Example 1-5

ingredient Content (ppm) Example 1 Example 2 Example 3 Example 4 Example 5 3-isothiazolinone 1.3 1.5 2.0 2.5 3.0 Ortho phosphate 15 20 15 20 25 Phosphonates 5 10 10 10 20 zinc 1.5 2 2.5 3 3.5

Phosphonate was purchased from Bayer, and 3-isothiazolinone was used by SK Chemical.

Comparative Example 1-5

After maintaining each concentration of the water treatment agent component shown in the following Table 3 in the test water quality of Table 1, add water to make 100% by weight of the whole, then experimented in the same manner as in Examples 1 to 5 and the corrosion rate and The results of microbial reduction are shown in Table 4.

Table 3 Water treatment agent composition of Comparative Examples 1-5

ingredient Content (ppm) Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 3-isothiazolinone - - 0.5 1.0 - Ortho phosphate - - - 5 10 Phosphonates - 5 10 - - zinc - - 0.5 - 0.5

[Table 4] Corrosion and microbial inhibition test results

Corrosion results (mdd) Residual Microbial Concentration After 5 Days (CFU / ml) Water Quality # 1 Water Quality # 2 Water Quality # 3 Water Quality # 4 Water Quality # 5 Water Quality # 1 Water Quality # 2 Water Quality # 3 Water Quality # 4 Water Quality # 5 Example 1 4.2 4.3 4.8 5.2 5.5 10 10 10 ² 10 ² 10 ² Example 2 3.8 4.0 4.1 4.5 4.9 0 0 10 10 10 Example 3 3.9 4.0 4.0 4.8 5.0 0 0 0 0 0 Example 4 2.7 2.9 2.9 3.1 3.2 0 0 0 0 0 Example 5 1.1 1.3 1.3 1.5 1.6 0 0 0 0 0 Comparative Example 1 278.3 298.4 303.0 312.4 342.3 10 ⁸ 10 ⁸ 10 ⁸ 10 ⁹ 10 ⁹ Comparative Example 2 45.3 46.0 48.4 51.2 53.7 10 ⁸ 10 ⁸ 10 ⁸ 10 ⁸ 10 ⁸ Comparative Example 3 34.7 38.6 40.5 42.3 45.8 10 ⁵ 10 ⁵ 10 ⁵ 10 ⁶ 10 ⁶ Comparative Example 4 30.7 28.7 34.5 40.5 47.7 10 ³ 10 ⁴ 10 ⁴ 10 ⁴ 10 ⁵ Comparative Example 5 13.2 16.8 19.6 20.4 22.6 10 ⁸ 10 ⁸ 10 ⁸ 10 ⁸ 10 ⁸

As can be seen from Table 4, the corrosion protection effect of Examples 1 to 5 was about 10 to 60 times higher than that of Comparative Examples 1 to 5, and the microbial sterilization effect was higher than that of Comparative Examples 1 to 5 at 10 ⁴ . 10 ⁸ is shown.

Therefore, the present invention is characterized in that it contains isothiazolinone, phosphate, zinc salt and phosphonate, and has a sustained bactericidal effect, which is excellent for disinfecting all microorganisms and can be generated on the metal surface. By suppressing the positive and negative reactions, which are chemical reactions, they have an excellent anticorrosive effect by minimizing the conditions where corrosion can occur, and have an excellent effect of simultaneously controlling corrosion and microbial slime.

Claims (7)

In the water treatment composition for inhibiting metal corrosion and microbial slime generation, the water treatment agent composition for inhibiting corrosion and microorganisms comprising isothiazolinone, phosphate, zinc salt and phosphonate of the formula [Formula 1] In Formula 1, R is hydrogen or chlorine. The composition of claim 1, wherein the composition comprises 0.05 to 14% of isothiazolinone, 0.5 to 50% of phosphate based on orthophosphate ions, 0.05 to 20% of zinc salt based on zinc ions, organic phosphonate A water treatment agent composition for inhibiting corrosion and microorganisms, having a composition ratio of 0.1 to 50% phosphonate on an ionic basis, and having a total weight of 100% by weight of water. The method of claim 1 or 2, wherein the isothiazolinone is 2-methyl-4-isothiazolone-3-one or 5-chloro-2-methyl-4-isothiazolone-3-one, Corrosion and characterized in that methyl-4-isothiazolone-3-one and the 5-chloro-2-methyl-4-isothiazolone-3-one are mixed in a weight ratio of 1:20 to 20: 1. Water treatment agent composition for inhibiting microorganisms. The method of claim 1 or 2, wherein the phosphate is selected from the group consisting of phosphoric acid, sodium monophosphate, sodium diphosphate, sodium triphosphate, potassium monophosphate, potassium diphosphate and potassium triphosphate. Water treatment agent composition. The method of claim 1 or 2, wherein the zinc salt is selected from zinc chloride, zinc sulfate and zinc nitrate water treatment composition for corrosion and microbial inhibition. 3. The phosphonate of claim 1 or 2, wherein the phosphonate is phosphonobutane tricarboxylic acid, hydroxyethylin diphosphonic acid, hydroxyphosphono carboxylic acid, aminotrimethylene phosphonic acid and ethylene diamine tetramethylidine phosphate. A water treatment agent composition for inhibiting corrosion and microorganisms, characterized in that selected from fornic acid. A method of inhibiting corrosion and microbial slime of an underwater metal, comprising administering the composition of claim 1 to various water pipes including a cooling tower and a heat exchanger.