Iminodisuccinate products with high copper chelation value and high calcium chelation value, and preparation and use thereof

Abstract

The application discloses an iminodisuccinic acid salt product with high copper chelation value and high calcium chelation value, and adopts a maleic anhydride process to produce the iminodisuccinic acid salt product, wherein the mass dosage molar ratio of L-aspartic acid, maleic anhydride and sodium hydroxide in raw materials is controlled to be 1:(1.03-1.06):(3.4-3.7), and the holding temperature of an ammonia addition reaction is controlled to be 100-105 DEG C, and the holding time is 12-14 hours. The iminodisuccinic acid salt product can make the calcium chelation value reach 330 mg / g or more while ensuring that all indexes of the product meet the requirements of industry standards, and can greatly improve the situation that a user adds a large amount of medicament and adds frequently due to the low calcium chelation capacity of the iminodisuccinic acid salt in daily use.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of imidosuccinate, in particular to an imidosuccinate with high copper chelating value and high calcium chelating value, and preparation and application of the imidosuccinate. BACKGROUND

[0002] Chelating agents are widely used in industrial and agricultural production and life due to their stable metal coordination ability. However, with the discharge of industrial and agricultural wastewater, a large amount of chelating agents enter the environment with the wastewater, not only causing pollution to water and soil due to the non-degradability of chelating agents, but also causing heavy metal accumulation in water and soil due to the chelating ability of chelating agents.

[0003] Imidosuccinate (IDS) is a new type of green chelating agent, which has excellent chelating performance and good biodegradability, and is widely used in many technical fields, especially in water treatment. The main functions of water treatment agents are to prevent scale, prevent corrosion, treat wastewater and alleviate water hardness, etc. IDS can not only combine with scale-forming ions such as calcium, magnesium, iron and copper in water to form water-soluble complexes, thereby avoiding the generation of scale and protecting the normal operation of pipelines and equipment, but also can combine with metal ions in water to form stable complexes, thereby reducing the concentration of metal ions and reducing the corrosion of metal ions to pipelines and equipment. In addition, IDS can be used to treat harmful metal ions in the wastewater treatment process to reduce the pollution of the environment, so it is used as an important chelating raw material for various water treatment agents.

[0004] However, based on the different chelating abilities of IDS to different metal ions, the chelating values of different metal ions are obviously different. For example, the chelating value of IDS to Mn 2+ is about 245 mg / g, the chelating value to Ca 2+ is about 214 mg / g, the chelating value to Cu 2+ is about 371 mg / g, and the chelating value to Fe 3+ is about 99 mg / g. The current conventional imidosuccinate product has a calcium chelating value of only about 220 mg / g, which may cause poor cleaning effect due to the low chelating ability to calcium ions. To solve this problem, users increase the dosage, which not only increases the cleaning cost and operation cost, but also increases the content of organic matter in the water treatment system, making it difficult for subsequent treatment. Therefore, users require that the imidosuccinate product significantly improve the calcium chelating value while maintaining the copper chelating value. SUMMARY

[0005] In order to solve the problem of insufficient calcium chelation value of imino disuccinate product, the imino disuccinate product with high copper chelation value and high calcium chelation value is provided, which can make the calcium chelation value reach more than 330 mg / g, and the highest can reach 354.67 mg / g, so that the condition that the user adds too much and too frequently due to the low calcium chelation ability of imino disuccinate in daily use can be greatly improved.

[0006] In order to achieve the above-mentioned purpose, the imino disuccinate product with high copper chelation value and high calcium chelation value provided by the present application is produced by using maleic anhydride process, and the molar ratio of the mass amount of L-aspartic acid, maleic anhydride and sodium hydroxide in the raw material is controlled to be 1:(1.03-1.06):(3.4-3.7), and the holding temperature after the ammonia addition reaction is controlled to be 100-105 DEG C, and the holding time is 12-14 h.

[0007] By adjusting the reaction conditions of imino disuccinate (IDS) produced by maleic anhydride process, including the amount ratio of reaction raw materials, ammonia addition reaction temperature and time, the composition of imino disuccinate product is changed, the calcium chelation ability is significantly improved without affecting the original excellent performance, such as effective component content and copper chelation ability. Specifically, by reducing the amount ratio of maleic anhydride and alkali, and reducing the reaction temperature and shortening the reaction time, the difference of main components is reflected in the product performance index detection results and infrared analysis spectrum, so that the copper chelation value is maintained, and the calcium chelation value is significantly improved, which has extremely important application value in practical application.

[0008] As a limitation of the above technical solution, in the maleic anhydride process, the acid-base reaction of maleic anhydride and sodium hydroxide is carried out first, and the reaction is carried out at 60-80 DEG C for 1-2 h, and after the reaction, the solution is clear, and L-aspartic acid is added for ammonia addition reaction.

[0009] As a limitation of the above technical solution, the conversion rate of imino disuccinate obtained after holding is >80%.

[0010] As a limitation of the above technical solution, the effective content of imino disuccinate in the imino disuccinate product is >32%, and the calcium chelation value is ≥330 mg / g.

[0011] As a limitation of the above technical solution, the copper chelation value of the imino disuccinate product is ≥380 mg / g, and other indexes meet the requirements of industry standards.

[0012] The preparation method of the imino disuccinate product with high copper chelation value and high calcium chelation value is provided, which comprises the following preparation steps:

[0013] Firstly, water, maleic anhydride and sodium hydroxide are added into a reaction kettle, and an acid-base reaction is carried out at 60-80 DEG C to generate sodium maleate, then L-aspartic acid is added to carry out an ammoniation reaction, and then the reaction solution is kept warm until the ammoniation reaction is completed, and then water is added to obtain the imino disuccinate product.

[0014] As a limitation of the above technical solution, the molar ratio of the first water amount to L-aspartic acid is 11-13:1, that is, the amount of water added into the reaction kettle is used for the ammoniation reaction of L-aspartic acid.

[0015] As a limitation of the above technical solution, the molar ratio of the second water amount to L-aspartic acid is 10-12:1, that is, the amount of water added into the reaction kettle is used for the ammoniation reaction of L-aspartic acid.

[0016] The preparation steps and conditions of the imino disuccinate product are improved, and the product performance is optimized.

[0017] Meanwhile, the application also provides the application of the imino disuccinate product with high copper chelating value and high calcium chelating value as described above, which is used as a cleaning agent for a circulating water system or a scale and corrosion inhibitor for a circulating water system.

[0018] The imino disuccinate product of the application has significantly improved calcium chelating capacity on the basis of maintaining the original excellent chelating capacity for different ions, and can greatly enhance the ability to clean calcium scale when used, and has universal applicability to water treatment systems.

[0019] In summary, the application does not affect the original excellent performance of the imino disuccinate product, and by regulating the preparation reaction of the product during preparation, the composition and component content of the product are affected, so that the calcium chelating capacity is significantly improved, the use amount and the addition frequency are greatly reduced when the product is used to clean calcium scale, the user use cost is reduced, the water quality and subsequent treatment are optimized, and the application has obvious application advantages and value. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 , calcium chelating value titration detection method;

[0021] Figure 2 , the left graph is the state before titration, and the right graph is the state after titration;

[0022] Figure 3 , titration result of example 1;

[0023] Figure 4 , titration result of comparative example 1;

[0024] Figure 5, infrared detection spectrum of imino disuccinate product of Example 1, wherein a is a complete spectrum, and b is a local enlarged view of the spectrum;

[0025] Figure 6 , infrared detection spectrum of imino disuccinate product of Comparative Example 1, wherein a is a complete spectrum, and b is a local enlarged view of the spectrum. DETAILED DESCRIPTION

[0026] The technical solutions of the present application will be described clearly and completely below in conjunction with the embodiments. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0027] The raw materials used in the following examples and comparative examples are typical products purchased on the market.

[0028] The copper chelating capacity detection method refers to the effective content detection in HG / T 5749-2020 Tetrasodium iminodisuccinate.

[0029] The imino disuccinic acid content determination method is as follows: according to the complex reaction of tetrasodium iminodisuccinate with copper ions at a molar ratio of 1:1 at a pH value of about 3.6, the content is determined by using potentiometric titration, and the tetrasodium iminodisuccinate content is calculated from the volume of copper sulfate standard titration solution consumed to the potential jump point (i.e. the theoretical end point).

[0030] Effective content calculation formula

[0031]

[0032] In the formula, V1 is the volume of copper sulfate standard titration solution consumed by the sample, mL; V0 is the volume of copper sulfate standard titration solution consumed by the blank, mL; c is the concentration of copper sulfate standard titration solution; M is the molecular weight of tetrasodium iminodisuccinate, g / mol (M = 337.1); and m is the weight of the sample.

[0033] Copper chelating value calculation formula

[0034]

[0035] In the formula, c is the concentration of copper sulfate standard solution, mol / L; V is the volume of copper sulfate standard solution consumed in titration, mL; m is the mass of the sample, g; s is the solid content of the sample, %; and M is the molar mass of CuSO4, g / mol (M = 160).

[0036] The calcium chelating ability detection method refers to the turbidity titration method in "Calcium Ion Chelating Force Test Method and Comparison" in Dyeing and Finishing Auxiliaries, December 2006, Vol. 23, No. 12, as shown below. The specific operation is as follows: about 5 g of chelating agent is weighed, dissolved with water and diluted to 500 ml in a volumetric flask, 10 ml is taken, 5 ml of ammonia-ammonium chloride buffer solution is added to adjust the pH value to about 10, 1 ml of sodium oxalate solution is added, and the solution is titrated with calcium acetate standard solution until it becomes turbid as the end point. Figure 1

[0037] Calcium chelating value calculation formula:

[0038]

[0039] In the formula, c is the concentration of the calcium acetate standard solution, mol / L; V is the volume of the calcium acetate standard solution consumed in titration, mL; m is the sample mass, g; s is the sample solid content, %; M is the molar mass of CaCO3, g / mol (M = 100.1).

[0040] The rest of the detection refers to "HG / T 5749-2020 Tetrasodium Imminodisuccinate".

[0041] Example 1

[0042] L-aspartic acid: maleic anhydride: sodium hydroxide = 1: 1.05: 3.4 (molar ratio);

[0043] The holding temperature is 104℃, and the holding time is 13h;

[0044] First, add water 1533.6 kg (85.2 mol), maleic anhydride 730.59 kg (7.455 mol) and sodium hydroxide 965.6 kg (24.14 mol) to the reaction kettle, and carry out acid-base reaction at 60-80℃. When the reaction solution is clear (about 1-2h), the reaction is completed to generate sodium maleate. Then add L-aspartic acid 944.3 kg (7.1 mol), and increase the kettle temperature to the holding temperature for ammonia addition reaction. After adding L-aspartic acid, the reaction solution will gradually become white emulsion and then clear and transparent. After the holding time is completed (i.e. the reaction is completed), imminodisuccinate is obtained. Then add water 1405.8 kg (78.1 mol) and stir uniformly to obtain imminodisuccinate product.

[0045] ​The obtained imino disuccinate product: colorless to light yellow transparent liquid, solid content 41.30%, effective content (imino disuccinate) 33.78%, conversion rate (copper chelating ability) 81.79%, L-aspartic acid 3.11%, butenedioic acid 1.19%, 1% solution (i.e. imino disuccinate product diluted 100 times) pH 10.87, copper chelating value 388.21 mg / g, calcium chelating value 354.67 mg / g.

[0046] The data of the calcium chelating value detection process are as follows:

[0047] The calcium acetate concentration is 0.2013 mol / L, the sample weighs 5.021 g, the imino disuccinate product is colorless and transparent liquid before titration, and the aminodisuccinate solution is turbid after titration, as shown in Figure 2 The titration consumes 7.3 mL of calcium acetate, as shown in Figure 3 The calculation shows that the calcium chelating value is 354.67 mg / g.

[0048] The data of the copper chelating value and effective content detection process are as follows:

[0049] The copper sulfate concentration is 0.1230 mol / L, the sample weighs 0.8224 g, and the copper sulfate consumption is 6.7 mL. The calculation shows that the copper chelating value is 388.21 mg / g, and the effective content is 33.78%.

[0050] The imino disuccinate product is subjected to infrared analysis, and the spectrum is shown in Figure 5 .

[0051] Example 2:

[0052] L-aspartic acid: maleic anhydride: sodium hydroxide = 1: 1.04: 3.7 (molar ratio);

[0053] The holding temperature is 104°C, and the holding time is 13 h;

[0054] First, 1661.4 kg (92.3 mol) of water, 723.63 kg (7.384 mol) of maleic anhydride, and 1050.8 kg (26.27 mol) of sodium hydroxide are added to the reaction kettle, and the acid-base reaction is carried out at 60-80°C. After the reaction solution is clear (about 1-2 h), the reaction is completed to generate sodium maleate. Then, 944.3 kg (7.1 mol) of L-aspartic acid is added, and the kettle temperature is raised to the holding temperature for ammonia addition reaction. After the addition of L-aspartic acid, the reaction solution gradually becomes white emulsion, and then slowly becomes clear and transparent. After the completion of the holding time, the imino disuccinate is obtained. Then, 1405.8 kg (78.1 mol) of water is added to the reaction kettle, and the imino disuccinate product is obtained after stirring.

[0055] The obtained imino disuccinate product: colorless to light yellow transparent liquid, solid content 40.61%, effective content 33.02%, conversion rate (copper chelating capacity) 81.31%, L-aspartic acid 3.08%, butenedioic acid 1.25%, 1% pH 10.88, copper chelating value 385.92 mg / g, calcium chelating value 347.03 mg / g.

[0056] The data of the calcium chelating value detection process are as follows:

[0057] The calcium acetate concentration is 0.2013 mol / L, the sample weighs 5.0043 g, and the volume of consumed calcium acetate is 7 ml.

[0058] The calculated calcium chelating value is 347.03 mg / g.

[0059] The data of the copper chelating value and effective content detection process are as follows:

[0060] The copper sulfate concentration is 0.1230 mol / L, the sample weighs 0.7911 g, and the volume of consumed copper sulfate is 6.3 ml.

[0061] The calculated copper chelating value is 385.92 mg / g, and the effective content is 33.02%.

[0062] Example 3:

[0063] L-aspartic acid: maleic anhydride: sodium hydroxide = 1: 1.06: 3.4;

[0064] The holding temperature is 104°C, and the holding time is 12 h.

[0065] First, 1405.8 kg (78.1 mol) of water, 737.55 kg (7.526 mol) of maleic anhydride, and 965.6 kg (24.14 mol) of sodium hydroxide are added to the reaction kettle, and an acid-base reaction is carried out at 60-80°C. After the reaction solution is clear (about 1-2 h), the reaction is completed to generate sodium maleate. Then, 944.3 kg (7.1 mol) of L-aspartic acid is added, and the kettle temperature is raised to the holding temperature for ammonia addition reaction. After the addition of L-aspartic acid, the reaction solution gradually becomes white and turbid, and then slowly becomes clear and transparent as the reaction proceeds. After the completion of the holding time, imino disuccinate is obtained. Then, 1278 kg (71 mol) of water is added again, and the imino disuccinate product is obtained after stirring uniformly.

[0066] The obtained imino disuccinate product: colorless to light yellow transparent liquid, solid content 40.97%, effective content 33.01%, conversion rate (copper chelating capacity) 80.57%, 1% pH 10.88, L-aspartic acid 3.03%, butenedioic acid 1.21%, copper chelating value 382.41 mg / g, calcium chelating value 348.49 mg / g.

[0067] The calcium chelating value detection process data are as follows:

[0068] The calcium chelating value detection process data are as follows:

[0069] The copper chelating value and effective content detection process data are as follows:

[0070] The copper chelating value and effective content detection process data are as follows:

[0071] Comparative Example 1

[0072] The comparative example adopts the preparation conditions of conventional imino disuccinate.

[0073] L-aspartic acid: maleic anhydride: sodium hydroxide = 1: 1.08: 3.8 (molar ratio);

[0074] The holding temperature is 107°C, and the holding time is 15 h;

[0075] First, 1405.8 kg (78.1 mol) of water, 751.46 kg (7.668 mol) of maleic anhydride and 1079.2 kg (26.98 mol) of sodium hydroxide are added to the reaction kettle, and the acid-base reaction is carried out at 60-80°C. After the reaction solution is clear (about 1-2 h), the reaction is completed to generate sodium maleate. Then, 944.3 kg (7.1 mol) of L-aspartic acid is added, and the kettle temperature is increased to the holding temperature for ammonia addition reaction. After the addition of L-aspartic acid, the reaction solution gradually becomes white emulsion, and then slowly becomes clear and transparent as the reaction proceeds. After the completion of the holding time, imino disuccinate is obtained. Then, 1661.4 kg (92.3 mol) of water is added again, and the imino disuccinate product is obtained after stirring.

[0076] The obtained imino disuccinate product: colorless to light yellow transparent liquid, solid content 41.43%, effective content 34.20%, conversion rate (copper chelating ability) 82.55%, 1% pH 10.93, L-aspartic acid 2.25%, butenedioic acid 1.98%, copper chelating value 381.79 mg / g, calcium chelating value 226.20 mg / g.

[0077] The calcium chelating value detection process data are as follows:

[0078] The calcium acetate concentration is 0.2013 mol / L, the sample weighs 4.9992 g, and the calcium acetate volume consumed is 4.65 ml, as shown in Figure 4 The calculation shows that the calcium chelating value is 226.20 mg / g.

[0079] The copper chelating value and effective content detection process data are as follows:

[0080] The copper sulfate concentration is 0.1230 mol / L, the sample weighs 0.8002 g, and the copper sulfate volume consumed is 6.6 ml, and the calculation shows that the copper chelating value is 391.79 mg / g, and the effective content is 34.20%.

[0081] The obtained imino disuccinate product: colorless to light yellow transparent liquid, solid content 41.43%, effective content 34.20%, conversion rate (copper chelating ability) 82.55%, 1% pH 10.93, L-aspartic acid 2.25%, butenedioic acid 1.98%, copper chelating value 381.79 mg / g, calcium chelating value 226.20 mg / g. Figure 6

[0082] The obtained imino disuccinate product: colorless to light yellow transparent liquid, solid content 41.43%, effective content 34.20%, conversion rate (copper chelating ability) 82.55%, 1% pH 10.93, L-aspartic acid 2.25%, butenedioic acid 1.98%, copper chelating value 381.79 mg / g, calcium chelating value 226.20 mg / g.

[0083] This comparative example is based on the conventional imino disuccinate (Comparative Example 1) product, and a trace amount of L-aspartic acid is additionally added.

[0084] The obtained imino disuccinate product: colorless to light yellow transparent liquid, solid content 41.43%, effective content 34.20%, conversion rate (copper chelating ability) 82.55%, 1% pH 10.93, L-aspartic acid 2.25%, butenedioic acid 1.98%, copper chelating value 381.79 mg / g, calcium chelating value 226.20 mg / g.

[0085] The calcium chelating value detection process data are as follows:

[0086] The calcium acetate concentration is 0.2013 mol / L, the sample weighs 4.9992 g, and the calcium acetate volume consumed is 4.65 ml, as shown in The calculation shows that the calcium chelating value is 226.20 mg / g.

[0087] The copper chelating value and effective content detection process data are as follows:

[0088] The copper sulfate concentration is 0.1230 mol / L, the sample weighs 0.8021 g, the copper sulfate consumption volume is 6.62 ml, and the copper chelation value is calculated as 391.20 mg / g, and the effective content is 34.22%.

[0089] Compared with the example, the copper chelation capacity of the comparative example 1 is slightly stronger, but the calcium chelation value is much worse; compared with the example, the L-aspartic acid content of the comparative example 2 is equivalent, the calcium chelation value is improved, but there is a big gap with the example, so simply increasing the L-aspartic acid content has little effect on improving the calcium chelation capacity.

[0090] In summary, under the premise of ensuring the copper chelation value, the product of the application improves the calcium chelation value, so that the product reduces the dosage and frequency of adding medicaments in the application process of circulating water, and reduces the use cost of customers.

Claims

1. An iminodisuccinate product possessing both high copper chelation value and high calcium chelation value, characterized in that: To produce iminodisuccinate using the maleic anhydride process, water, maleic anhydride, and sodium hydroxide are first added to the reaction vessel. An acid-base reaction is carried out at 60-80°C to generate sodium maleate. After the reaction solution becomes clear and the reaction is completed, L-aspartic acid is added to carry out an ammonia reaction. The temperature is then maintained. After the maintenance time is completed, iminodisuccinate is obtained. Water is then added to adjust the product to meet the requirements. The molar ratio of L-aspartic acid, maleic anhydride, and sodium hydroxide in the raw materials is controlled at 1:(1.03~1.06):(3.4~3.7), and the holding temperature of the ammonia addition reaction is controlled at 100~105℃ and the holding time is controlled at 12~14h.

2. The iminodisuccinate product with both high copper chelation value and high calcium chelation value according to claim 1, characterized in that: In the maleic anhydride process, the acid-base reaction between maleic anhydride and sodium hydroxide is carried out first at 60~80℃ for 1~2 hours. After the solution is clear after the reaction, L-aspartic acid is added to carry out the ammonia addition reaction.

3. The iminodisuccinate product with both high copper chelation value and high calcium chelation value according to claim 2, characterized in that: The conversion rate of iminodisuccinate obtained after the heat preservation period is >80%.

4. The iminodisuccinate product with both high copper chelation value and high calcium chelation value according to claim 3, characterized in that: The effective content of iminodisuccinate in the iminodisuccinate product is >32%, and the calcium chelation value is ≥330mg / g.

5. The iminodisuccinate product with both high copper chelation value and high calcium chelation value according to claim 4, characterized in that: The copper chelation value of the iminodisuccinate product is ≥380mg / g, and other indicators meet the industry standard requirements.

6. The method for preparing the iminodisuccinate product with both high copper chelation value and high calcium chelation value as described in any one of claims 1 to 5, characterized in that, The preparation steps include the following: First, water, maleic anhydride, and sodium hydroxide are added to the reaction vessel, and an acid-base reaction is carried out at 60~80℃ to produce sodium maleate. After the reaction solution becomes clear, the reaction is stopped. Then, L-aspartic acid is added to carry out an ammonia reaction. The temperature is kept warm, and after the holding time is completed, iminodisuccinate is obtained. Water is then added to adjust the product to obtain the iminodisuccinate product that meets the requirements.

7. The method for preparing the iminodisuccinate product with both high copper chelation value and high calcium chelation value according to claim 6, characterized in that: The initial water addition was in a molar ratio of 11 to 13:1 to L-aspartic acid.

8. The method for preparing the iminodisuccinate product with both high copper chelation value and high calcium chelation value according to claim 7, characterized in that: The molar ratio of water added in the second addition to L-aspartic acid is 10~12:

1.

9. The application of the iminodisuccinate product with both high copper chelation value and high calcium chelation value as described in any one of claims 1 to 5, characterized in that: Used as a cleaning agent or scale and corrosion inhibitor for circulating water systems.

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