A tracing type complex scale inhibitor based on benzofuran fluorescent agent and a preparation method and application thereof

Abstract

This invention provides a tracer-type compound scale inhibitor based on benzofuran fluorescent agents, its preparation method, and its application. In the tracer-type compound scale inhibitor, the mass ratio of scale inhibitor to benzofuran fluorescent agent is (20-100):1; the benzofuran fluorescent agent is [6-hydroxy-2-(2-hydroxy-4-oxocyclohexyl-2,5-diene-1-yl)benzofuran-3-one]; the scale inhibitor is selected from acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer and / or ethylenediaminetetramethylene phosphate sodium. The benzofuran fluorescent agent of this invention combines real-time concentration detection and scale inhibition performance, exploring the potential of fluorescent tracers in water treatment. Due to the synergistic effect between BD and PAA, the tracer-type compound scale inhibitor prepared by this invention exhibits good fluorescence stability and excellent calcium carbonate scale inhibition rate, allowing for widespread application in circulating cooling water systems and other fields with relatively low dosage.

Description

Technical Field

[0001] This invention relates to a tracer-type compound scale inhibitor based on benzofuran fluorescent agents, its preparation method and application, belonging to the field of water treatment technology. Background Technology

[0002] In industrial production, various scale-forming ions (SO42-) are commonly present in water systems. 2- CO3 2- Ca 2+ These ions gradually form scale as the circulating water system operates, depositing on the pipe walls and causing serious economic losses and operational problems. Therefore, identifying suitable scale inhibitors is crucial to ensuring the normal operation of circulating cooling water systems, and accurately measuring the concentration of scale inhibitors is essential for achieving their optimal effect. Since the water quality of circulating cooling water systems may change constantly in actual industrial production, real-time monitoring of scale inhibitor concentration is vital.

[0003] Currently, the commonly used methods for detecting scale inhibitor concentration in industry mainly include the following: 1. Total phosphorus content detection: This method assesses the scale inhibitor concentration by detecting the total phosphorus content in the water. However, it is environmentally unfriendly and has been gradually phased out. 2. Atomic absorption spectrometry: Although accurate, this method is cumbersome to operate and has a time lag, making it difficult to meet the needs of real-time monitoring. 3. Fluorescence tracer technology: This technology directly measures the fluorescence intensity of the scale inhibitor, thereby detecting its concentration in real time. These technologies have become research hotspots in fields such as fluorescent dyes and biosensors due to their high sensitivity and selectivity. However, the synthesis process of fluorescent scale inhibitors constructed from traditional fluorescent dyes (such as coumarin) is complex, the raw material cost is high, and some synthesized fluorescent scale inhibitors have poor stability, making them difficult to apply in practical water systems.

[0004] Therefore, it is of great significance to select a suitable scale inhibitor and fluorescent agent to formulate a tracer-type compound scale inhibitor for use in circulating cooling water systems. Summary of the Invention

[0005] To address the aforementioned technical problems, the present invention aims to provide a tracer-type compound scale inhibitor based on benzofuran fluorescent agents, its preparation method, and its application, thereby solving the technical problem that fluorescent scale inhibitors struggle to simultaneously achieve stable fluorescence performance and excellent scale inhibition effect.

[0006] To achieve the above objectives, in a first aspect, the present invention provides a tracer-type compound scale inhibitor based on benzofuran fluorescent agents, wherein the mass ratio of the scale inhibitor to the benzofuran fluorescent agent in the tracer-type compound scale inhibitor is (20-100):1. If too much scale inhibitor is added, the prepared tracer-type compound scale inhibitor will undergo fluorescence quenching and cannot be detected by fluorescence; while if the fluorescent dose is too small, its scale inhibition effect will be reduced.

[0007] The benzofuran fluorescent agent is [6-hydroxy-2-(2-hydroxy-4-oxocyclohexyl-2,5-diene-1-yl)benzofuran-3-one] (BD);

[0008] The scale inhibitor is selected from acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer (PAA) and / or sodium ethylenediaminetetramethylene phosphate.

[0009] According to a specific embodiment of the present invention, preferably, the scale inhibitor is selected from acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer.

[0010] According to a specific embodiment of the present invention, preferably, the scale inhibitor has a solid content of 30% and a weight-average molecular weight of 2000-5000.

[0011] According to a specific embodiment of the present invention, preferably, in the tracer-type compound scale inhibitor, the mass ratio of scale inhibitor PAA to benzofuran fluorescent agent is (50-70):1, more preferably 60:1.

[0012] Secondly, the present invention provides a method for preparing a tracer-type compound scale inhibitor based on benzofuran fluorescent agents as described above, comprising the following steps:

[0013] The scale inhibitor is mixed with a benzofuran fluorescent agent and stirred for 5-15 minutes to prepare a tracer-type compound scale inhibitor based on the benzofuran fluorescent agent.

[0014] According to a specific embodiment of the present invention, preferably, the scale inhibitor is physically blended with a benzofuran fluorescent agent for 10 minutes to obtain the tracer-type compound scale inhibitor.

[0015] According to a specific embodiment of the present invention, preferably, the BD is prepared by the following steps:

[0016] Step 1: Add resorcinol to glyoxylic acid solution until the solid is completely dissolved, then add 0.1-0.5 mL of hydrochloric acid solution, more preferably 2 mL; heat and stir in an oil bath at 90-130°C for 1-3 hours, more preferably at 110°C for 1.5 hours; wherein the ratio of resorcinol to glyoxylic acid solution is (1.5-3) g: (0.5-0.7) mL, more preferably 2.4 g: 0.6 mL.

[0017] Step 2: Wash and filter the solution obtained in Step 1 with deionized water, and then vacuum dry to obtain a mixture;

[0018] Step 3: Dissolve the mixture obtained in Step 2 in anhydrous ethanol, add potassium hydroxide, heat to 40-60℃ and stir for 1-4 hours, more preferably heat to 50℃ and stir for 2 hours; cool the solution to room temperature and vacuum dry to obtain the BD; wherein, the mass ratio of the mixture to potassium hydroxide is 1:(0.2-0.6), more preferably 1:0.42; the volume ratio of the mixture to anhydrous ethanol is (0.5-2)g:(8-12)mL, more preferably 1g:9.6mL.

[0019] Secondly, the present invention provides an application of the tracer-type compound scale inhibitor based on benzofuran fluorescent agents as described above in circulating cooling water treatment.

[0020] According to a specific embodiment of the present invention, preferably, the tracer-type compound scale inhibitor is used to inhibit and detect scale in circulating cooling water.

[0021] According to a specific embodiment of the present invention, preferably, the dosage of the tracer-type compound scale inhibitor is 2-40 mg / L, more preferably 20 mg / L.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] This invention synthesizes BD using resorcinol and glyoxylic acid as raw materials through esterification and nucleophilic addition reactions. Compared to traditional fluorescent agents, BD combines online concentration detection and scale inhibition performance, achieving a scale inhibition rate of 55% for calcium carbonate scale at a dosage of 40 mg / L. Subsequently, PAA and BD are blended to prepare a tracer-type compound scale inhibitor based on benzofuran fluorescent agents. Because the -OH group of BD can enhance the scale inhibition performance of acrylate-2-acrylamide-2-methylpropanesulfonic acid copolymer against calcium carbonate, a synergistic effect is achieved, significantly improving the scale inhibition effect, with a scale inhibition rate of up to 98.1% for calcium carbonate scale. The tracer-type compound scale inhibitor of this invention exhibits good fluorescence stability during online detection and also possesses excellent calcium carbonate scale inhibition rate, allowing for widespread application in circulating cooling water systems and other fields with a relatively small dosage. Attached Figure Description

[0024] Figure 1 This is the Fourier infrared spectrum of BD in an embodiment of the present invention.

[0025] Figure 2 This is the fluorescence spectrum of BD at a concentration of 10 mg / L in an embodiment of the present invention.

[0026] Figure 3 This is a graph showing the fluorescence emission spectrum of BD and the linear relationship between its concentration and fluorescence intensity in an embodiment of the present invention.

[0027] Figure 4This is the fluorescence spectrum of BD-PAA at a concentration of 20 mg / L in an embodiment of the present invention.

[0028] Figure 5 This is a graph showing the fluorescence emission spectrum of BD-PAA and the linear relationship between its concentration and fluorescence intensity in an embodiment of the present invention.

[0029] Figure 6a This is a comparison of the fluorescence intensities of BD-PMA, BD-EDTMPS, and BD-PAA at a concentration of 10 mg / L.

[0030] Figure 6b This is a comparison of the fluorescence intensity of BD-EDTMPS and BD-PAA at a concentration of 5 mg / L.

[0031] Figure 7 This is a comparison chart of the scale inhibition performance of BD-PAA and BD-EDTMPS on calcium carbonate.

[0032] Figure 8 This is a comparison chart of the scale inhibition performance of calcium carbonate by BD, PAA, and BD-PAA at different concentrations. Detailed Implementation

[0033] 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.

[0034] Example 1

[0035] This embodiment provides a method for preparing a tracer-type compound scale inhibitor based on benzofuran fluorescent agents, including the following steps:

[0036] Step 1: Add resorcinol to glyoxylic acid solution and dissolve the solid completely. Then add concentrated hydrochloric acid solution and stir magnetically in an oil bath at 110°C for 1.5 hours.

[0037] Step 2: Wash and filter the solution obtained in Step 1 with deionized water, and then vacuum dry it.

[0038] Step 3: Dissolve the product obtained in Step 2 in anhydrous ethanol, add potassium hydroxide, heat to 50°C, stir for 2 hours, cool the solution to room temperature and then dry under vacuum to obtain BD;

[0039] Step 4: Stir the product obtained in Step 3 in water with a magnetic force to make the solution evenly mixed;

[0040] Step 5: Add PAA to the solution obtained in Step 4 and mix thoroughly. The mass ratio of PAA to BD is 20:1, resulting in BD-PAA, a tracer-type compound scale inhibitor based on benzofuran fluorescent agents.

[0041] Example 2

[0042] This embodiment provides a method for preparing a tracer-type compound scale inhibitor based on benzofuran fluorescent agents, which differs from Example 1 only in that the mass ratio of PAA to BD is 40:1.

[0043] Example 3

[0044] This embodiment provides a method for preparing a tracer-type compound scale inhibitor based on benzofuran fluorescent agents, which differs from Example 1 only in that the mass ratio of PAA to BD is 60:1.

[0045] Example 4

[0046] This embodiment provides a method for preparing a tracer-type compound scale inhibitor based on benzofuran fluorescent agents, which differs from Example 1 only in that the mass ratio of PAA to BD is 80:1.

[0047] Example 5

[0048] This embodiment provides a method for preparing a tracer-type compound scale inhibitor based on benzofuran fluorescent agents, which differs from Example 1 only in that the mass ratio of PAA to BD is 100:1.

[0049] Comparative Examples 1-5

[0050] This comparative example provides a method for preparing a tracer-type compound scale inhibitor based on benzofuran fluorescent agents, including the following steps:

[0051] Step 1: Add resorcinol to glyoxylic acid solution and dissolve the solid completely. Then add concentrated hydrochloric acid solution and heat in an oil bath at 110°C with stirring for 1.5 hours.

[0052] Step 2: Wash and filter the solution obtained in Step 1 with deionized water, and then vacuum dry it.

[0053] Step 3: Dissolve the product obtained in Step 2 in anhydrous ethanol, add potassium hydroxide, heat to 50°C, stir for 2 hours, cool the solution to room temperature and then vacuum dry to obtain BD;

[0054] Step 4: Stir BD magnetically in water to mix the solution evenly;

[0055] Step 5: Mix the maleic acid-acrylic acid copolymer PMA evenly, add it to the solution obtained in Step 4 and mix evenly to obtain the BD-based tracer-type compound scale inhibitor BD-PMA.

[0056] The mass ratios of PMA to BD were 20:1 (Comparative Example 1), 40:1 (Comparative Example 2), 60:1 (Comparative Example 3), 80:1 (Comparative Example 4), and 100:1 (Comparative Example 5).

[0057] Comparative Examples 6-10

[0058] This comparative example provides a method for preparing a tracer-type compound scale inhibitor based on benzofuran fluorescent agents, including the following steps:

[0059] Step 1: Add resorcinol to glyoxylic acid solution and dissolve the solid completely. Then add concentrated hydrochloric acid solution and heat in an oil bath at 110°C with stirring for 1.5 hours.

[0060] Step 2: Wash and filter the solution obtained in Step 1 with deionized water, and then vacuum dry it.

[0061] Step 3: Dissolve the product obtained in Step 2 in anhydrous ethanol, add potassium hydroxide, heat to 50°C, stir for 2 hours, cool the solution to room temperature and then vacuum dry to obtain BD;

[0062] Step 4: Stir BD magnetically in water to mix the solution evenly;

[0063] Step 5: Mix sodium ethylenediaminetetramethylene phosphate (EDTMPS) evenly, add it to the solution obtained in Step 4, and mix evenly to obtain BD-EDTMPS, a tracer-type compound scale inhibitor based on benzofuran fluorescent agents.

[0064] The mass ratios of EDTMPS to BD were 20:1 (Comparative Example 6), 40:1 (Comparative Example 7), 60:1 (Comparative Example 8), 80:1 (Comparative Example 9), and 100:1 (Comparative Example 10).

[0065] Example

[0066] The above examples and comparative examples were characterized by infrared spectroscopy and fluorescence spectroscopy, respectively, for BD and BD-PAA, a tracer-type compound scale inhibitor based on benzofuran fluorescent agents. The fluorescence and scale inhibition performance of BD-PAA, BD-PMA and BD-EDTMPS were compared. The results showed that the scale inhibition and fluorescence performance of BD-PAA of the present invention were significantly stronger than those of the other two scale inhibitors.

[0067] according to Figure 1 It can be seen that the stretching vibration peak of the -OH bond on the benzene ring appears at 3435 cm⁻¹. -1 Location, 1619cm -1 The absorption peak at 1519 cm⁻¹ corresponds to the stretching vibration peak of C=O, indicating that the hydroxyl group on the benzene ring is oxidized to the quinone form. -1 and 1460cm -1The absorption peak at 1383 cm⁻¹ corresponds to the stretching vibration peak of the benzene ring. -1 The absorption peak at that point is the CO stretching vibration peak, which confirms the successful synthesis of BD.

[0068] Figure 2 The fluorescence spectrum of BD at 10 mg / L is shown. Figure 2 It can be seen that when BD is excited by light with a wavelength of 471nm, it has a maximum emission peak at 534nm, and the excitation spectrum and emission spectrum of BD show a good mirror symmetry relationship, which indicates that BD has good fluorescence properties.

[0069] Figure 3 The graph shows the fluorescence emission spectrum of BD and the linear relationship between its concentration and fluorescence intensity. Figure 3 As can be seen, within the concentration range of 2-10 mg / L, the fluorescence intensity increases with increasing concentration, showing a linear positive correlation between fluorescence intensity and concentration. R 2 =0.999.

[0070] Figure 4 The figure shows the fluorescence spectrum of BD-PAA (mass ratio of BD to PAA is 1:60). It can be seen from the figure that the fluorescence excitation spectrum and emission spectrum of BD-PAA have a good mirror symmetry relationship. The optimal excitation wavelength and the optimal emission wavelength of BD-PAA and BD with a ratio of 1:60 are the same. Therefore, the emission spectrum is plotted with 471nm as the optimal excitation wavelength, and the maximum emission peak is also reached at 523nm.

[0071] according to Figure 5 It can be seen that when the concentration is in the range of 5-40 mg / L, the fluorescence intensity increases with the increase of BD-PAA concentration, and the fluorescence intensity is linearly positively correlated with the BD-PAA concentration. 2 =0.991. This indicates that BD-PAA (BD to PAA mass ratio of 1:60) has excellent fluorescence properties.

[0072] Figure 6a This is a fluorescence intensity graph of BD with three tracer-type compound scale inhibitors at different concentrations. The graph shows that when the ratios of BD with the three different tracer-type compound scale inhibitors are 1:20, 1:40, 1:60, 1:80, and 1:100, BD-PAA exhibits the highest fluorescence intensity, followed by BD-EDTMPS, and BD-PMA exhibits the lowest fluorescence intensity. Since not all fluorescent agents retain fluorescence after physical compounding with scale inhibitors, BD-PMA experiences fluorescence quenching when the dosage of all three scale inhibitors is 10 mg / L. Figure 6bAs can be seen, when the dosage of the remaining two tracer-type compound scale inhibitors with unquenched fluorescence is 5 mg / L, both BD-PAA and BD-EDTMPS with a ratio of 1:100 undergo fluorescence quenching.

[0073] from Figure 7 It can be seen that the scale inhibition rate of BD-PAA is higher with the increase of the dosage of BD-PAA and BD-EDTMPS. When the dosage is 20 mg / L and the mass ratio of BD to PAA is 1:60, the scale inhibition rate of BD-PAA can reach 98.1%, producing a threshold effect. Therefore, the scale inhibition performance and fluorescence performance are optimal when the mass ratio of BD to PAA is 1:60.

[0074] The tracer-type compound scale inhibitor BD-PAA (mass ratio of BD to PAA of 1:60) based on benzofuran fluorescent agents was used in a simulated cooling water system to test the scale inhibition rate of calcium carbonate (CaCO3) at different dosage concentrations.

[0075] Figure 8 This is a comparison of the scale inhibition performance of different concentrations of BD, BD-PAA, and PAA on CaCO3. First, the scale inhibition performance of the fluorescent agent BD was measured. The graph shows that BD has a certain scale inhibition performance on CaCO3. When the dosage of BD is 20 mg / L... -1 At that time, its scale inhibition rate reached 39.7%; when the dosage was 40 mg·L⁻¹ -1 At this point, a threshold effect occurs after the CaCO3 scale inhibition rate reaches 55%. Secondly, as shown in the figure, when the dosage of BD-PAA and PAA is both 20 mg / L, the scale inhibition rates are 98.1% and 90.2%, respectively. This indicates that when the scale inhibitor PAA is added to BD, in addition to enabling online concentration monitoring, BD-PAA has a better CaCO3 scale inhibition ability than PAA. This is because PAA does not contain -OH groups, and there is no competitive or inhibitory relationship between BD and PAA. The -OH groups in BD can, to some extent, compensate for the CaCO3 scale inhibition performance of PAA, thus playing a synergistic role and achieving excellent scale inhibition effect.

[0076] In summary, when the dosage of BD is 40 mg / L, the scale inhibition rate of calcium carbonate scale can reach 55%. When PAA is added to BD, in addition to enabling real-time monitoring, the scale inhibition rate of the prepared tracer-type compound scale inhibitor is even better. In particular, in Example 3, when the mass ratio of BD to PAA is 1:60 and the dosage of BD-PAA is 20 mg / L, the scale inhibition rate of calcium carbonate scale can reach 98.1%, and its fluorescence and scale inhibition performance are optimal. After adding PAA to BD, it has both online concentration detection and scale inhibition performance.

Claims

1. A tracer type complexing scale inhibitor based on benzofuran class of fluorescing agent wherein, In the aforementioned tracer-type compound scale inhibitor, the mass ratio of scale inhibitor to benzofuran fluorescent agent is (20-100):1; The benzofuran fluorescent agent is [6-hydroxy-2-(2-hydroxy-4-oxocyclohexyl-2,5-diene-1-yl)benzofuran-3-one]; The scale inhibitor is selected from acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer and / or sodium ethylenediaminetetramethylene phosphate.

2. The tracer-type compounded scale inhibitor according to claim 1, wherein, The scale inhibitor is selected from acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer; And / or, the scale inhibitor has a solid content of 30% and a weight-average molecular weight of 2000-5000.

3. The tracer-type compounded scale inhibitor according to claim 1, wherein, The mass ratio of the scale inhibitor to the benzofuran fluorescent agent is (50-70):

1.

4. A method for preparing a tracer-type compound scale inhibitor as described in any one of claims 1-3, wherein, Includes the following steps: The scale inhibitor is mixed with a benzofuran fluorescent agent and stirred for 5-15 minutes to prepare a tracer-type compound scale inhibitor based on the benzofuran fluorescent agent.

5. The method for preparing the tracer-type compound scale inhibitor according to claim 4, wherein, The benzofuran-based fluorescent agent BD is prepared using the following steps: Step 1: Add resorcinol to glyoxylic acid solution until the solid is completely dissolved, then add 0.1-0.5 mL of concentrated hydrochloric acid solution and heat and stir in an oil bath at 90-130℃ for 1-3 hours. Step 2: Wash and filter the solution obtained in Step 1 with deionized water, and then vacuum dry to obtain a mixture; Step 3: Dissolve the mixture obtained in Step 2 in anhydrous ethanol, add potassium hydroxide, heat to 40-60℃ and stir for 1-4 hours. After cooling the solution to room temperature, dry it under vacuum.

6. The method for preparing the tracer-type compound scale inhibitor according to claim 5, wherein, In step one, the ratio of resorcinol to glyoxylic acid solution is (1.5-3) g : (0.5-0.7) mL.

7. The method for preparing the tracer-type compound scale inhibitor according to claim 5, wherein, In step three, the mass ratio of the mixture to potassium hydroxide is 1:(0.2-0.6); the volume ratio of the mixture to anhydrous ethanol is (0.5-2)g:(8-12)mL.

8. The application of a tracer-type compound scale inhibitor based on benzofuran fluorescent agents as described in any one of claims 1-3 in circulating cooling water treatment.

9. The application according to claim 8, wherein, The aforementioned tracer-type compound scale inhibitor was used to inhibit and detect scale in circulating cooling water.

10. The application according to claim 8, wherein, The dosage of the tracer-type compound scale inhibitor is 20 mg / L.

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