Resveratrol-based micromolecular scale inhibitor as well as preparation and application thereof

Abstract

The invention discloses a resveratrol-based micromolecular scale inhibitor as well as preparation and application thereof, and belongs to the field of industrial and commercial circulating cooling water. The natural product-based micromolecule scale inhibitor is synthesized by taking resveratrol as a raw material. Static scale inhibition experiments and concentration ratio tests show that the scale inhibition performance of 0.01 wt% of the resveratrol-based small molecular scale inhibitor on calcium ions at 80 DEG C is better than that of sodium polyacrylate and EDTA-2Na with the same mass concentration, the calcium ion concentration of supernatant liquid after addition is 151.66 mg / L, and the resveratrol-based small molecular scale inhibitor is still clear after concentration. The resveratrol-based micromolecular scale inhibitor disclosed by the invention is efficient, green and environment-friendly, and a new scheme is provided for circulating water treatment.

Description

TECHNICAL FIELD

[0001] The present application relates to a class of resveratrol-based small molecule scale inhibitors, their preparation and application, and belongs to the field of industrial and commercial circulating cooling water. BACKGROUND

[0002] Circulating cooling water systems play an important role in industrial production and building operation activities. Through water circulation, heat generated during the production process or equipment operation can be removed, maintaining the normal operation of production or equipment. However, as the concentration ratio of open cooling water increases, the concentration of calcium and magnesium ions in the water increases, and the water quality deteriorates, which is prone to scale formation. Scale formation can form an insulating layer on the surface of the heat exchanger, reducing heat transfer and affecting the normal operation of the equipment. In addition, scale formation can also cause pipe blockage, equipment failure, and even require maintenance, resulting in production interruption and additional maintenance costs.

[0003] Scale inhibitors play a crucial role in circulating water treatment, which can react with calcium, magnesium and other ions in water to form stable complexes, preventing the deposition of dissolved minerals in equipment, pipes and cooling systems to avoid scale formation. Polymer scale inhibitors are the most commonly used type. Common polymer scale inhibitors include polyacrylic acid, polycarboxylic acid, polyurethane, polyvinyl alcohol and polyphosphate. They prevent crystalline deposition by reacting with calcium and magnesium ions in water and are widely used in industrial circulating water and cooling water treatment. However, polymer scale inhibitors are easily affected by changes in water quality, and organic matter or pollutants in water can interfere with their effectiveness; long-term use can cause flocculation, affecting water flow and equipment efficiency. In addition, some polymers are difficult to degrade and may pose a risk to the ecosystem. Traditional scale inhibitors such as polyphosphates and organic phosphates have hydrolysis and toxicity problems, and their effectiveness in complex water quality is poor.

[0004] Compared with polymer scale inhibitors, small molecule scale inhibitors have fast diffusion speed, sensitive solubility to temperature changes, easy degradation, and easy compounding with polymer scale inhibitors, making them a relatively ideal choice for scale inhibitors. However, some common small molecule chelating agents such as EDTA or sodium citrate can also bind to calcium and magnesium ions, providing some scale inhibition, but the resulting complex has low solubility and weak interaction with polymer scale inhibitors, making it easy to form mixed crystals, which is one of the sources of hard scale.

[0005] Therefore, how to design new small molecule structures to obtain small molecule scale inhibitors with good scale inhibition performance and compounding performance is one of the difficult problems that need to be solved in the field of water treatment. SUMMARY

[0006] [TECHNICAL PROBLEM]

[0007] Traditional small molecule scale inhibitors are easy to form mixed crystals, which is one of the sources of hard scale.

[0008] [Technical scheme]

[0009] In order to solve the above problems, the present application takes natural product resveratrol as raw material, introduces larger hydrophobic group in the molecule, to weaken the interaction of the molecule with the surface of the calcium carbonate crystal formed in the process of complexing calcium and magnesium ions, to provide a more efficient, green and environmentally friendly solution for water treatment field.

[0010] The first object of the present application is to provide a kind of resveratrol-based small molecule scale inhibitor, its structural formula is as follows:

[0011]

[0012] Wherein, n=0, 1, 2.

[0013] The second object of the present application is to provide a method for synthesizing resveratrol-based small molecule scale inhibitor, the synthetic route is as follows:

[0014]

[0015] Wherein, n=0, 1, 2.

[0016] In an embodiment of the present application, the synthesis method is specifically as follows:

[0017] (1) resveratrol and anhydrous potassium carbonate are added to acetone, heated to 60 DEG C, and reacted for 0.5 h, then heated to 65 DEG C, and ethyl acid is added at one time, and the reaction process is monitored in real time by thin layer chromatography; after the reaction is completed, the filtrate is obtained by suction filtration, and the acetone is removed by rotary evaporation under reduced pressure, at this time, a yellow viscous liquid is obtained, which is separated by column chromatography to obtain compound I;

[0018] Wherein, the amount ratio of resveratrol, anhydrous potassium carbonate, ethyl acid and acetone is 0.1 mol:0.6 mol:0.32 mol:300 mL:

[0019] The ethyl acid is one of 2-bromopropionic acid ethyl ester, 3-bromobutyric acid ethyl ester and 4-bromopentanoic acid ethyl ester;

[0020] (2) compound I is dissolved in anhydrous ethanol, and added to a three-necked flask equipped with a reflux condenser, the temperature is raised to 85-90 DEG C, and then anhydrous ethanol containing sodium hydroxide is added, and the reaction is continued for 10 h; then the reaction mixture is centrifuged, washed and dried to obtain compound II;

[0021] The compound I, sodium hydroxide, anhydrous ethanol, and anhydrous ethanol containing sodium hydroxide are in a ratio of 0.05682 moL:0.182 moL:200 mL:100 mL. The washing is performed by using anhydrous ethanol for 3-5 times, and the drying is performed in a vacuum drying box.

[0022] A third object of the present application is to provide a new composite scale inhibitor containing the resveratrol-based small molecule scale inhibitor.

[0023] In an embodiment of the present application, the composite scale inhibitor contains the resveratrol-based small molecule scale inhibitor and sodium polyacrylate in a mass ratio of 1-3:1-3.

[0024] A fourth object of the present application is the application of the resveratrol-based small molecule scale inhibitor in the field of water treatment.

[0025] A fifth object of the present application is to provide a method for inhibiting the precipitation of calcium carbonate in water, comprising the following steps:

[0026] The resveratrol-based small molecule scale inhibitor is added into the water containing calcium carbonate.

[0027] In an embodiment of the present application, the concentration of calcium ions in the water is 500-600 mg / L.

[0028] In an embodiment of the present application, the mass concentration of the resveratrol-based small molecule scale inhibitor in the water is 0.005-0.1%.

[0029] [Advantages]

[0030] (1) The present application has a better chelating effect by rationally designing the molecular structure of the small molecule scale inhibitor, and reduces the interaction between the molecule and the surface of calcium carbonate or magnesium carbonate crystal, so that the mixed crystal is not easily formed.

[0031] (2) The resveratrol-based small molecule scale inhibitor of the present application can make 532 mg / L of calcium ions dissolved in water to form a clear solution when the addition amount is 0.01 wt%, while the water sample with a single polymer scale inhibitor or without a scale inhibitor has white precipitate. This indicates that the new small molecule scale inhibitor has a good effect of complexing divalent ions.

[0032] (3) The raw material used in the resveratrol-based small molecule scale inhibitor of the present application is resveratrol, which is easy to degrade and has good environmental compatibility, and will not cause secondary pollution to water quality. It is a green and environmentally friendly product with excellent performance. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 This is the nuclear magnetic resonance hydrogen spectrum of compound II in Example 1 (measured in CD3OD).

[0034] Figure 2 The calcium concentration standard curve chart for atomic absorption method.

[0035] Figure 3 The static scale inhibition experiment chart of the scale inhibitor used in Example 2 and Comparative Examples 1-3.

[0036] Figure 4 The solution appearance chart of the static scale inhibition solution of the scale inhibitor used in Example 2 and Comparative Examples 1-3 after being concentrated 15 times at 50°C.

[0037] Figure 5 The static scale inhibition experiment chart of the composite scale inhibitor with different compounding mass ratios (resveratrol-based small molecule scale inhibitor: sodium polyacrylate) used.

[0038] Figure 6 The static scale inhibition experiment chart of the scale inhibitor containing 0.01%, 0.005%, and 0.001% of the resveratrol-based small molecule scale inhibitor used in Example 6, respectively. DETAILED DESCRIPTION

[0039] The preferred embodiments of the present application are described below, and it should be understood that the embodiments are for better explaining the present application and are not used to limit the present application.

[0040] The raw materials used in the embodiments are as follows:

[0041] Resveratrol: 98% purity, commercially available;

[0042] 2-bromopropionic acid ethyl ester, 3-bromobutyric acid ethyl ester, 4-bromopentanoic acid ethyl ester, anhydrous potassium carbonate, acetone, anhydrous ethanol, and sodium hydroxide are all conventional experimental raw materials.

[0043] Example 1

[0044] A method for synthesizing a resveratrol-based small molecule scale inhibitor, comprising the following steps:

[0045] (1) resveratrol (22.8 g, 0.1 mol) and anhydrous potassium carbonate (82.8 g, 0.6 mol) are added to 300 mL of acetone, and the temperature is raised to 60°C, and the reaction is carried out for 0.5 h; then the temperature is raised to 65°C, and 2-bromopropionic acid ethyl ester (58 g, 0.32 mol) is added at one time, and the reaction progress is monitored in real time by thin layer chromatography; when the resveratrol corresponding point on the thin layer chromatography plate disappears, the reaction is considered to be completed; after the reaction is completed, the filtrate is obtained by suction filtration, and the solvent acetone is removed by rotary evaporation under reduced pressure; at this time, a yellow viscous liquid is obtained, which is separated by column chromatography to obtain compound I with n = 0;

[0046] The above compound I (30 g, 0.05682 mol) was dissolved in 200 mL of anhydrous ethanol, added to a three-necked flask equipped with a reflux condenser, the temperature was raised to 90°C, 100 mL of anhydrous ethanol containing sodium hydroxide (7.3 g, 0.182 mol) was added, and the reaction was continued for 10 h, after which the reaction mixture was centrifuged to obtain a white precipitate; the precipitate was washed with anhydrous ethanol 4 times and dried in a vacuum drying oven to obtain the final product compound II with n = 0.

[0047] The specific synthesis route is as follows:

[0048]

[0049] Wherein, n = 0.

[0050] The nuclear magnetic resonance hydrogen spectrum result of the final product is as follows: Figure 1

[0051] 1 H NMR (400 MHz, MeOD) δ 7.41 (d, J = 9.7 Hz, 2H), 7.04 (d, J = 16.4 Hz, 1H), 6.92-6.85 (m, 3H), 6.68-6.63 (m, 2H), 6.42 (q, J = 2.3 Hz, 1H), 4.54 (q, J = 6.5 Hz, 3H), 1.58-1.52 (m, 9H).

[0052] It can be seen from Figure 1 that Example 1 indeed obtained a white mulberry alcohol-based small molecule scale inhibitor.

[0053] Example 2

[0054] A method for inhibiting the precipitation of calcium carbonate in water, comprising the following steps:

[0055] A 532 mg / L calcium chloride aqueous solution was prepared as hard water for testing in the experiment;

[0056] The hard water solution was taken, and the white mulberry alcohol-based small molecule scale inhibitor of Example 1 with a concentration of 0.01 wt% was added, which was recorded as 0.01% white mulberry alcohol-based scale inhibitor.

[0057] Subsequently, sodium bicarbonate was added to the solution to a mass concentration of 806.4 mg / L, and then incubated in a 80°C water bath for 10 h to reach an equilibrium state, and then cooled.

[0058] Comparative Example 1

[0059] In Example 2, the white mulberry alcohol-based small molecule scale inhibitor of Example 1 was replaced by sodium polyacrylate, and the rest was the same as Example 2; it was recorded as 0.01% sodium polyacrylate.

[0060] ​Comparative Example 2

[0061] Adjust the "resveratrol-based small molecule scale inhibitor of Example 1" in Example 2 to EDTA-2Na, and keep the rest of Example 2 unchanged; recorded as 0.01% EDTA-2Na.

[0062] Comparative Example 3

[0063] Adjust the "resveratrol-based small molecule scale inhibitor of Example 1" in Example 2 to deionized water, and keep the rest of Example 2 unchanged; recorded as 0.01% deionized water.

[0064] The calcium ion concentration of the supernatant in Example 2 and Comparative Examples 1-3 was measured by atomic absorption spectrometry. The higher the calcium ion concentration of the supernatant, the fewer calcium ions involved in the formation of calcium carbonate precipitate, i.e. the better the scale inhibition performance. The scale inhibition performance of resveratrol-based small molecule scale inhibitors, sodium polyacrylate, and EDTA-2Na can be compared.

[0065] The calcium concentration standard curve is shown in Figure 2 , and the specific equation is y = -0.0259 + 0.00795x (where y is the absorbance and x is the calcium element concentration in μg / mL).

[0066] Figure 3 The static scale inhibition test diagram of the scale inhibitors used in Example 2 and Comparative Examples 1-3. The calcium ion concentration of the supernatant in Example 2 (0.01% resveratrol-based scale inhibitor), Comparative Example 1 (0.01% sodium polyacrylate), Comparative Example 2 (0.01% EDTA-2Na), and Comparative Example 3 (0.01% deionized water) was 151.66 mg / L, 87.78 mg / L, 79.48 mg / L, and 21.53 mg / L, respectively. That is, the effect of Example 2 is better than that of Comparative Examples 1-3.

[0067] The relevant performance evaluation of scale inhibitors for circulating water was carried out by static scale inhibition method concentration ratio test. The supernatant of Example 2 (0.01% resveratrol-based scale inhibitor), Comparative Example 1 (0.01% sodium polyacrylate), Comparative Example 2 (0.01% EDTA-2Na), and Comparative Example 3 (0.01% deionized water) was heated and volatilized in a 50°C water bath to concentrate to 1 / 15 of the original solution mass, and the scale inhibition effect is shown in Figure 4 . As can be seen from Figure 4 , the solution of Example 2 (0.01% resveratrol-based scale inhibitor) is still clear, i.e. no calcium carbonate precipitate is produced, the solutions of Comparative Example 1 (0.01% sodium polyacrylate) and Comparative Example 2 (0.01% EDTA-2Na) have a slight turbidity, and the solution of Comparative Example 3 (0.01% deionized water) has a significant turbidity.

[0068] Example 3

[0069] A method for synthesizing a resveratrol-based small molecule scale inhibitor, comprising the following steps:

[0070] Resveratrol (22.8 g, 0.1 mol) and anhydrous potassium carbonate (82.8 g, 0.6 mol) were added to 300 mL of acetone, and the temperature was raised to 60°C, and reacted for 0.5 h; then the temperature was raised to 65°C, and 3-bromobutyric acid ethyl ester (66.9 g, 0.32 mol) was added at one time, and the reaction process was monitored in real time by thin layer chromatography; when the resveratrol corresponding point on the thin layer chromatography plate disappeared, it indicated that the reaction was completed; after the reaction was completed, filtration was carried out again to obtain the filtrate, and the solvent acetone was removed by rotary evaporation under reduced pressure at this time, and a yellow viscous liquid was obtained, which was separated by column chromatography to obtain compound I with n = 1;

[0071] The above compound I (35 g, 0.057 mol) was dissolved in 200 mL of anhydrous ethanol, and a three-necked flask equipped with a reflux condenser was added, the temperature was raised to 90°C, and 100 mL of anhydrous ethanol containing sodium hydroxide (7.3 g, 0.182 mol) was added, and the reaction was continued for 10 h, and then the reaction mixture was centrifuged to obtain a white precipitate; the precipitate was washed with anhydrous ethanol 4 times, and dried in a vacuum drying box to obtain the final product compound II with n = 1.

[0072] The specific synthesis route is as follows:

[0073]

[0074] Wherein, n = 1.

[0075] Example 4

[0076] A method for synthesizing a resveratrol-based small molecule scale inhibitor, comprising the following steps:

[0077] Resveratrol (22.8 g, 0.1 mol) and anhydrous potassium carbonate (82.8 g, 0.6 mol) were added to 300 mL of acetone, and the temperature was raised to 60°C, and reacted for 0.5 h; then the temperature was raised to 65°C, and 3-bromobutyric acid ethyl ester (66.9 g, 0.32 mol) was added at one time, and the reaction process was monitored in real time by thin layer chromatography; when the resveratrol corresponding point on the thin layer chromatography plate disappeared, it indicated that the reaction was completed; after the reaction was completed, filtration was carried out again to obtain the filtrate, and the solvent acetone was removed by rotary evaporation under reduced pressure at this time, and a yellow viscous liquid was obtained, which was separated by column chromatography to obtain compound I with n = 1;

[0078] The above compound I (37.3 g, 0.057 mol) was dissolved in 200 mL of anhydrous ethanol, added to a three-necked flask equipped with a reflux condenser, the temperature was raised to 90°C, 100 mL of anhydrous ethanol containing sodium hydroxide (7.3 g, 0.182 mol) was added, and the reaction was continued for 10 h, after which the reaction mixture was centrifuged to obtain a white precipitate; the precipitate was washed with anhydrous ethanol 4 times and dried in a vacuum drying oven to obtain the final product compound II with n = 2.

[0079] The specific synthesis route is as follows:

[0080]

[0081] wherein n = 2.

[0082] The white alpinenyl small molecule scale inhibitors synthesized in Examples 3 and 4 can effectively inhibit the precipitation of calcium carbonate in water.

[0083] Example 5 New composite scale inhibitor

[0084] Adjust the amount of "alpinenyl scale inhibitor of Example 1" in Example 2 to be a new composite scale inhibitor with a mass ratio of alpinenyl small molecule scale inhibitor of Example 1 to sodium polyacrylate of 1:1, 1:2, 1:3, 2:1, and 3:1, and the total mass concentration is 0.01%, and the rest is consistent with Example 2.

[0085] Figure 5 The static scale inhibition experiment graph of the composite scale inhibitor with different compounding mass ratios (alpinenyl small molecule scale inhibitor: sodium polyacrylate) is shown in the figure. The calcium ion concentration of the supernatant was measured by atomic absorption method when the mixture with a mass ratio of alpinenyl small molecule scale inhibitor and sodium polyacrylate of 1:1, 1:2, 1:3, 2:1, and 3:1 was added, and the total mass concentration was 0.01%. The calcium ion concentration of the supernatant was 151.66 mg / L, 108.42 mg / L, 94.73 mg / L, 145.58 mg / L, and 143.89 mg / L, respectively. That is, among these several ratios, the composite scale inhibitor with a mass ratio (alpinenyl small molecule scale inhibitor: sodium polyacrylate) of 1:1 has the best scale inhibition effect.

[0086] Example 6

[0087] Adjust the amount of "alpinenyl scale inhibitor of Example 1" in Example 2 to be 0.001% and 0.005%, and the rest is consistent with Example 2.

[0088] Figure 6The static scale inhibition experiment graph of using different amounts of resveratrol-based small molecule scale inhibitors. The calcium ion concentration of the supernatant after adding 0.001% and 0.005% of the resveratrol-based small molecule scale inhibitor is 53.48 mg / L and 107.34 mg / L respectively, measured by atomic absorption method.

[0089] Although the present application has been disclosed in the above with preferred embodiments, it is not intended to limit the present application, and any person skilled in the art can make various modifications and modifications without departing from the spirit and scope of the present application, and therefore the protection scope of the present application should be defined by the claims.

Claims

1. A resveratrol-based small molecule scale inhibitor, characterized in that: The structural formula is as follows: Among them, n=0, 1, 2.

2. A method for synthesizing the resveratrol-based small molecule scale inhibitor according to claim 1, characterized in that: The synthetic route is as follows: Among them, n=0, 1, 2.

3. The method according to claim 2, characterized in that The synthesis method is as follows: (1) Resveratrol and anhydrous potassium carbonate were added to acetone, heated to 60°C, and reacted for 0.5 h. The temperature was then raised to 65°C, and ethyl acetate was added all at once. The reaction progress was monitored in real time by thin-layer chromatography. After the reaction was completed, the filtrate was filtered to obtain a filtrate, and the acetone was removed by vacuum rotary evaporation to obtain a yellow viscous liquid, which was then separated by column chromatography to obtain Compound I. (2) Compound I was dissolved in anhydrous ethanol and added to a three-necked flask equipped with a reflux condenser. The temperature was raised to 85-90°C, and anhydrous ethanol containing sodium hydroxide was added. The reaction was continued for 10 hours. The reaction mixture was then centrifuged, washed, and dried to obtain Compound II.

4. The method according to claim 3, characterized in that The usage ratio of resveratrol, anhydrous potassium carbonate, ethyl acetate and acetone is 0.1 mol: 0.6 mol: 0.32 mol: 300 mL.

5. The method according to claim 3, characterized in that The usage ratio of compound I, sodium hydroxide, anhydrous ethanol, and anhydrous ethanol containing sodium hydroxide is 0.05682 moL:0.182 moL:200 mL:100 mL.

6. A new type of composite scale inhibitor, characterized in that: Contains the resveratrol-based small molecule scale inhibitor according to claim 1.

7. The composite scale inhibitor according to claim 6, characterized in that The composite scale inhibitor comprises a resveratrol-based small molecule scale inhibitor and sodium polyacrylate, and the mass ratio of the two is 1-3:1-3.

8. Use of the resveratrol-based small molecule scale inhibitor according to claim 1 in the field of water treatment.

9. A method for inhibiting calcium carbonate precipitation in water, characterized in that: The steps include: The resveratrol-based small molecule scale inhibitor according to claim 1 is added to water containing calcium carbonate.

10. The method according to claim 9, characterized in that The concentration of calcium ions in water is 500-600 mg / L; the mass concentration of the resveratrol-based small molecule scale inhibitor in water is 0.005-0.1%.

Images