Method for treating wastewater containing a triazole-based compound

Abstract

The present application provides a method for treating wastewater containing a triazole compound, which comprises adding hypochlorous acid with a neutral or slightly acidic pH to the wastewater containing the triazole compound to react, so that more than 90% of the triazole compound can be effectively reacted and treated.

Description

Technical Field

[0001] This invention relates to a wastewater treatment method for triazole compounds, and more particularly to a wastewater treatment method that uses hypochlorous acid solution to react with triazole compounds. Background Technology

[0002] In the manufacturing of electronic components such as wafers and circuit boards, a large amount of waste liquid containing triazole compounds is generated during the production of electronic components such as wafers or circuit boards. Currently, most of these waste liquids are degraded using biological treatment processes. However, this method requires a lot of land and is time-consuming. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a method for treating wastewater containing triazole compounds, which involves reacting the triazole compounds with hypochlorous acid (HOCl) with a slightly acidic pH value, effectively treating over 90% of the triazole substances.

[0004] This invention provides a method for treating wastewater containing triazole compounds, comprising:

[0005] Adjust the pH of the wastewater containing triazole compounds to between pH 3 and 10; and

[0006] Hypochlorous acid solution is added to the wastewater to treat the concentration of the triazole compound to below a critical concentration, wherein the pH of the hypochlorous acid solution is 3 to 7. Attached Figure Description

[0007] Figure 1 This is a flowchart of the treatment method for wastewater containing triazole compounds according to the present invention.

[0008] Explanation of symbols in the attached drawings: S1~S2: steps Detailed Implementation

[0009] In order to provide a clearer understanding of the technical features, objectives and beneficial effects of the present invention, the technical solution of the present invention will now be described in detail below, but it should not be construed as limiting the scope of implementation of the present invention.

[0010] The following detailed descriptions of various embodiments of the present invention, along with accompanying drawings, will provide the reader with a better understanding. In addition to these detailed descriptions, the present invention can be widely implemented in other embodiments. Any easy substitutions, modifications, or equivalent changes to the described embodiments should be understood to be included within the scope of the present invention, and the scope of the patent should be defined by the claims. It should be noted that the drawings are for illustrative purposes only and do not represent the actual size or quantity of the components; some details may not be fully depicted for the sake of simplicity.

[0011] Please refer to Figure 1This is a flow chart of the treatment method for wastewater containing triazole compounds according to the present invention. First, the wastewater containing triazole compounds is adjusted with hydrochloric acid or sulfuric acid and sodium hydroxide solution until its pH value is 3-10 (step S1). The concentration of triazole compounds in the wastewater is between 5 and 1,000 ppm, with particularly good results observed at 5-100 ppm. In some embodiments, the hypochlorous acid solution has a pH value of 3-7, which is slightly acidic, and exhibits preferred reaction effects.

[0012] The pH of wastewater containing triazole compounds can be adjusted using hydrochloric acid, sulfuric acid, or sodium hydroxide solution by any method known in the art until the desired pH value is achieved, and the amount of hydrochloric acid, sulfuric acid, or sodium hydroxide solution added can be determined according to the required pH value.

[0013] Similarly, the pH of a hypochlorous acid solution can be adjusted using sodium hypochlorite or sodium hydroxide solution by any method known in the art until the desired pH is achieved. The amount of hydrochloric acid, sulfuric acid, or sodium hydroxide solution added depends on the desired pH value. Hypochlorous acid solutions are commercially available.

[0014] Next, the wastewater containing triazole compounds is treated with a hypochlorous acid solution (step S2). The pH of the hypochlorous acid solution is preferably between pH 5 and 7, and the concentration is between 800 and 120,000 ppm. The concentration ratio of the hypochlorous acid solution to the triazole compounds in the wastewater is 800-120,000:5-1,000. The volume ratio of the hypochlorous acid solution to the wastewater is 0.001-1:1. The preferred reaction temperature is 20-40°C, and the preferred pressure is atmospheric pressure.

[0015] The reaction is terminated when the concentration (or critical concentration) of the triazole compound is below 0.5 ppm. In some embodiments, the concentration (or critical concentration) of the triazole compound is below 0.03 ppm. Therefore, the amount of hypochlorous acid solution added is determined based on the concentration of the triazole compound in the wastewater or the volume of the wastewater until the concentration of the triazole compound in the wastewater decreases to the critical concentration.

[0016] Triazole compounds refer to compounds containing methylbenzotriazole, benzotriazole, 1,2,4-triazole or combinations thereof, wherein the reaction product of methylbenzotriazole with hypochlorous acid and the reaction product of benzotriazole with hypochlorous acid are the same, and the reaction formulas of the three are shown in Table 1 below.

[0017] Table 1

[0018]

[0019]

[0020] Table 2

[0021] experimental group T-450 I II Hypochlorous acid (ppm) - 800 1,600 Triazole compounds (ppm) 10.53 2.14 0.03 Removal rate (%) - 79.73 99.69

[0022] Table 3

[0023] experimental group T-450 I II III Hydrogen peroxide (ppm) - 800 1,600 3,200 Triazole compounds (ppm) 16.1 16.1 16.0 16.0 Removal rate (%) - - - -

[0024] Comparing the removal efficiencies of hypochlorous acid (Table 2) and hydrogen peroxide (Table 3) on triazole compounds, it is clear that hypochlorous acid can effectively remove triazole compounds.

Claims

1. A method for treating wastewater containing triazole compounds, characterized in that: Adjust the pH of the wastewater containing triazole compounds to pH 3-10; and Hypochlorous acid solution is added to the wastewater to treat the concentration of the triazole compound to below a critical concentration of 0.5 ppm, wherein the pH of the hypochlorous acid solution is 3 to 7. The concentration ratio of the hypochlorous acid solution to the triazole compound in the wastewater is 800~120000:5~1000.

2. The processing method as described in claim 1, characterized in that, The pH value of the wastewater is adjusted using hydrochloric acid solution, sulfuric acid solution, sodium hydroxide solution, or a combination thereof.

3. The processing method as described in claim 1, characterized in that, The pH value of this hypochlorous acid solution is 5-7.

4. The processing method as described in claim 1, characterized in that, The concentration of this hypochlorous acid solution is 800-120000 ppm.

5. The processing method as described in claim 1, characterized in that, The volume ratio of the hypochlorous acid solution to the wastewater is 0.001-1:

1.

6. The processing method as described in claim 5, characterized in that, The critical concentration is 0.03 ppm.

7. The processing method as described in claim 1, characterized in that, The concentration of this triazole compound is 10-20 ppm.

8. The processing method as described in claim 1, characterized in that, The triazole compounds include methylbenzotriazole, benzotriazole, 1,2,4-triazole or combinations thereof.

9. The processing method as described in claim 1, characterized in that, The reaction temperature for the degradation of this wastewater by the hypochlorous acid solution is 20~40℃.

10. The processing method as described in claim 1, characterized in that, The reaction pressure at which the hypochlorous acid solution degrades the wastewater is atmospheric pressure.

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