Rosin amine compounded deep eutectic solvent corrosion inhibitor as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of auxiliaries for pipeline transportation, and particularly relates to a rosin amine compounded deep eutectic solvent corrosion inhibitor as well as a preparation method and application thereof. The corrosion inhibitor is formed by compounding a deep eutectic solvent and rosin amine, the deep eutectic solvent is composed of a hydrogen bond donor (HBD) and a hydrogen bond acceptor (HBA). The preparation method of the rosin amine compounded deep eutectic solvent comprises the following steps: mixing a hydrogen bond donor and a hydrogen bond acceptor, and heating in a water bath to obtain a pure clear and transparent deep eutectic solvent; and adding rosin amine into the deep eutectic solvent to obtain the rosin amine compounded deep eutectic solvent. The rosin amine compounded deep eutectic solvent corrosion inhibitor can be applied to a carbon dioxide conveying pipeline, is low in price and good in corrosion inhibition effect, and when the corrosion inhibitor is added into the carbon dioxide conveying pipeline, the use concentration is 200-500 ppm, and the corrosion inhibition effect can reach 95% or above.

Description

Technical Field

[0001] This invention belongs to the technical field of pipeline transportation additives, specifically relating to a rosin amine compound deep eutectic solvent corrosion inhibitor, its preparation method, and its application. Background Technology

[0003] Various technologies exist for pipeline corrosion protection, including metal coatings, electrochemical methods, and the use of corrosion-resistant materials. Among these, a relatively convenient and inexpensive method is to add corrosion inhibitors. This significantly reduces the rate at which CO2 corrodes pipelines.

[0004] Therefore, this invention provides a rosin amine compound deep eutectic solvent, its preparation method and application, which can reduce CO2 corrosion of pipelines. Summary of the Invention

[0005] In view of the problems existing in the above and / or prior art, the present invention is proposed. The present invention relates to a rosin amine compound deep eutectic solvent corrosion inhibitor and its preparation method.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] The first aspect of this invention is to provide a rosin amine-based deep eutectic solvent corrosion inhibitor, wherein the corrosion inhibitor is composed of a deep eutectic solvent and rosin amine; the deep eutectic solvent is composed of a hydrogen bond donor (HBD) and a hydrogen bond acceptor (HBA), wherein:

[0008] The molar ratio of the hydrogen bond donor (HBD) to the hydrogen bond acceptor (HBA) is (1-3):1; the molar ratio of the deep eutectic solvent to rosin amine is (1-5):1.

[0009] In a preferred embodiment of the preparation method described in this invention, the hydrogen bond acceptor (HBA) is choline chloride; and the hydrogen bond donor (HBD) is citric acid.

[0010] In a preferred embodiment of the preparation method described in this invention, the molar ratio of choline chloride to citric acid is 2:1, and the molar ratio of deep eutectic solvent to rosin amine is 3:7.

[0011] A second aspect of this invention provides a method for preparing a rosin amine complex deep eutectic solvent, comprising:

[0012] A pure and transparent deep eutectic solvent was obtained by mixing a certain proportion of hydrogen bond donors and hydrogen bond acceptors and then heating in a water bath.

[0013] Adding rosin amine to the deep eutectic solvent yields a rosin amine-based deep eutectic solvent.

[0014] In a preferred embodiment of the preparation method described in this invention, the hydrogen bond acceptor HBA is choline chloride; and the hydrogen bond donor HBD is citric acid.

[0015] The ratio of hydrogen bond donor HBD to hydrogen bond acceptor HBA (here, molar ratio / molar ratio / volume ratio) is 1 to 3:1.

[0016] The ratio of the deep eutectic solvent to rosin amine is (1-5):1.

[0017] The water bath temperature is 70-80℃, and the duration is 1-2 hours.

[0018] A third aspect of the present invention provides the application of the above-mentioned rosin amine compounded deep eutectic solvent corrosion inhibitor in carbon dioxide transmission pipelines.

[0019] As a preferred embodiment of the application described in this invention, the application in the field of pipeline transportation additives is that rosin amine compounded deep eutectic solvent can be used as a corrosion inhibitor for long-distance carbon dioxide pipeline transportation. The corrosion inhibitor is added to the carbon dioxide transportation pipeline at a concentration of 200-500 ppm.

[0020] As a preferred embodiment of the application described in this invention, the corrosion inhibition effect of the corrosion inhibitor for long-distance carbon dioxide pipeline transportation can reach over 95%.

[0021] The fourth aspect of the present invention provides a method for preventing corrosion of a carbon dioxide transmission pipeline, wherein the above-mentioned rosin amine compound deep eutectic solvent corrosion inhibitor is added to the transmission pipeline, and the concentration of the corrosion inhibitor is 200-500 ppm.

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

[0023] (1) Based on the idea of ​​“reducing costs”, this invention develops a rosin amine compound deep eutectic solvent corrosion inhibitor. Rosin amine is inexpensive, priced at 2,500 yuan / ton, which is cheaper than traditional corrosion inhibitors, thus reducing costs.

[0024] (2) Based on the idea of ​​“improving corrosion inhibition efficiency”, this invention develops a new type of corrosion inhibitor. Compared with the original corrosion inhibitor, the corrosion inhibition efficiency is improved. When the corrosion inhibitor is added to the carbon dioxide conveying pipeline, the concentration is 200-500ppm, and the corrosion inhibition effect can reach more than 95%. Detailed Implementation

[0025] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the examples in the specification.

[0026] To provide a clearer understanding of the technical features, objectives, and beneficial effects of the present invention, an embodiment of the invention is further described. This embodiment is only for further illustration and should not be construed as limiting the scope of protection of the present invention. Non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention also fall within the scope of protection of the present invention.

[0027] Example 1

[0028] This embodiment describes the preparation of a rosin amine compound deep eutectic solvent corrosion inhibitor, including the following steps:

[0029] (1) Hydrogen bond donor (HBD) choline chloride and hydrogen bond acceptor (HBA) citric acid are mixed in a 2:1 molar ratio. After mixing, the mixture is heated in a water bath at 80°C for 1 hour to obtain a pure and transparent deep eutectic solvent.

[0030] (2) A certain proportion of rosin amine is added to the pure and transparent deep eutectic solvent to obtain a rosin amine compound deep eutectic solvent. The deep eutectic solvent and rosin amine are mixed in a molar ratio of 5:5 to obtain a rosin amine compound deep eutectic solvent corrosion inhibitor.

[0031] Example 2

[0032] The difference between this embodiment and Example 1 is that the molar ratio of rosin amine to deep eutectic solvent is replaced with 4:6, while the rest of the steps are the same as in Example 1.

[0033] Example 3

[0034] The difference between this embodiment and Example 1 is that the molar ratio of rosin amine to deep eutectic solvent is replaced with 3:7, while the rest of the steps are the same as in Example 1.

[0035] Example 4

[0036] The difference between this embodiment and Example 1 is that the molar ratio of rosin amine to deep eutectic solvent is replaced with 2:8, while the rest of the steps are the same as in Example 1.

[0037] Example 5

[0038] This embodiment describes the corrosion inhibition performance test of a rosin-amine compound deep eutectic solvent corrosion inhibitor, including the following steps:

[0039] (1) The steel commonly used for CO2 pipeline transportation is processed into sheets with a length of about 50mm, a width of 10mm, and a thickness of 3mm.

[0040] (2) Polish the hanging piece with sandpaper step by step, clean it with ethanol, put it in a drying oven to dry, and weigh it after drying.

[0041] (3) Prepare 5 wide-mouth bottles, add pipeline CO2 produced water containing 300 ppm rosin amine and pipeline CO2 produced water containing 300 ppm rosin amine compounded deep eutectic solvent prepared in Examples 1 to 4 respectively, and take out the tablets after 7 days in the wide-mouth bottles respectively.

[0042] (4) After removing the plate, acid wash to remove corrosion products, clean and dry it and weigh it. Calculate the average corrosion rate and slow release rate based on the mass loss of the plate. At the same time, measure the deepest pitting depth, calculate the pitting rate, and calculate the corrosion inhibition efficiency. The corrosion inhibition efficiency is shown in Table 1.

[0043] Corrosion / corrosion inhibition rate is calculated using the following formula:

[0044]

[0045] In the formula: Rcorr is the corrosion rate, mm / a; m is the mass of the substrate before the experiment, g; mt is the mass of the substrate after the experiment, g; S1 is the surface area of ​​the substrate, cm². 2 ρ represents the density of the hanging material (g / cm³). 3 ; t is the experimental time, h; 8.76×10⁴ is the unit conversion constant.

[0046] The sustained-release efficiency is calculated using the following formula:

[0047]

[0048] In the formula: Vo -- corrosion rate of the metal without corrosion inhibitor, in mm / a; V -- corrosion rate of the metal with corrosion inhibitor, in mm / a; η -- corrosion inhibition efficiency of the corrosion inhibitor.

[0049] Table 1

[0050] sample Corrosion inhibition efficiency Rosin amine: Deep eutectic solvent ratio 5:5 92.5％ Rosin amine: Deep eutectic solvent ratio 4:6 94.7％ Rosin amine: Deep eutectic solvent ratio 3:7 95.8％ Rosin amine: Deep eutectic solvent ratio 2:8 92.1％ Rosin amine 91.5％

[0051] Table 1 shows that the corrosion inhibition efficiency of rosin amine combined with deep eutectic solvent is higher than that of rosin amine alone. Furthermore, the corrosion inhibition efficiency is best when the ratio of rosin amine to deep eutectic solvent is around 3:7.

[0052] Example 6

[0053] (1) The steel commonly used for CO2 pipeline transportation is processed into a sheet with a length of about 50mm, a width of 10mm, and a thickness of 3mm, and a small opening of 5mm is made on the top.

[0054] (2) Take four wide-mouth bottles and add the produced water from the pipeline CO2 into them.

[0055] (3) One wide-mouth bottle contains no corrosion inhibitor; another wide-mouth bottle contains a mixture of rosin amine and deep eutectic solvent in a molar ratio of 5:5, resulting in a concentration of 200 ppm; another wide-mouth bottle contains a mixture of rosin amine and deep eutectic solvent in a molar ratio of 5:5, resulting in a concentration of 400 ppm; and another wide-mouth bottle contains a mixture of rosin amine and deep eutectic solvent in a molar ratio of 5:5, resulting in a concentration of 500 ppm.

[0056] (4) The weighed plates were hung in the experimental media with and without corrosion inhibitors respectively. After soaking for 7 days under the specified conditions, they were taken out and the corrosion inhibition efficiency was calculated. Table 2 shows the corrosion inhibition effect of rosin amine compounded deep eutectic solvent under CO2 corrosion conditions.

[0057] Table 2

[0058] sample Concentration / ppm Corrosion inhibition efficiency Rosin amine compound deep eutectic solvent 0 / Rosin amine compound deep eutectic solvent 200 92.3％ Rosin amine compound deep eutectic solvent 400 93.7％ Rosin amine compound deep eutectic solvent 500 95.8％

[0059] Table 2 shows that the corrosion inhibition efficiency of rosin amine compounded deep eutectic solvent is related to its concentration, and within a certain range, the higher the concentration, the higher the corrosion inhibition efficiency.

[0060] Comparative Example 1

[0061] This comparative example is a compound without rosin amine, using only the same deep eutectic solvent as the corrosion inhibitor.

[0062] Preparation of deep eutectic solvent: Hydrogen bond donor (HBD) choline chloride and hydrogen bond acceptor (HBA) citric acid are mixed in a 2:1 molar ratio. After mixing, the mixture is heated in a water bath at 80°C for 1 hour to obtain a pure and transparent deep eutectic solvent.

[0063] To verify the corrosion inhibition effect of using only the same deep eutectic solvent in the compound formulation as a corrosion inhibitor under CO2 corrosion conditions, the following steps were performed:

[0064] (1) The steel commonly used for CO2 pipeline transportation is processed into a sheet with a length of about 50mm, a width of 10mm, and a thickness of 3mm, and a small opening of 5mm is made on the top.

[0065] (2) Take four wide-mouth bottles and add the produced water from the pipeline CO2 into them.

[0066] (3) No corrosion inhibitor was added to one wide-mouth bottle, and the above-mentioned deep eutectic solvent was added to the other three identical wide-mouth bottles respectively so that its concentration was 200ppm, 400ppm and 500ppm.

[0067] (4) The weighed plates were hung in the experimental media with and without corrosion inhibitors respectively. After soaking for 7 days under the specified conditions, they were taken out and the corrosion inhibition efficiency was calculated. Table 3 shows the corrosion inhibition effect of the same deep eutectic solvent when compounded under CO2 corrosion conditions.

[0068] Table 3

[0069]

[0070]

[0071] The data from Example 6 and Comparative Example 1 show that, at the same concentration, the release efficiency of the corrosion inhibitor without rosin amine is lower than that of the rosin amine compounded with a deep eutectic solvent.

[0072] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. A rosin-amine compound deep eutectic solvent corrosion inhibitor, characterized in that, The corrosion inhibitor is a compound of a deep eutectic solvent and rosin amine; the deep eutectic solvent is composed of a hydrogen bond donor (HBD) and a hydrogen bond acceptor (HBA), wherein: The molar ratio of the hydrogen bond donor (HBD) to the hydrogen bond acceptor (HBA) is (1-3):1; the molar ratio of the deep eutectic solvent to rosin amine is (1-5):

1.

2. The rosin amine compound deep eutectic solvent corrosion inhibitor according to claim 1, characterized in that, The hydrogen bond acceptor (HBA) is choline chloride; the hydrogen bond donor (HBD) is citric acid.

3. The rosin amine compound deep eutectic solvent corrosion inhibitor according to claim 2, characterized in that, The molar ratio of choline chloride to citric acid is 2:1, and the molar ratio of deep eutectic solvent to rosin amine is 3:

7.

4. A method for preparing a rosin amine compound deep eutectic solvent as described in any one of claims 1-3, characterized in that, include: A pure and transparent deep eutectic solvent was obtained by mixing hydrogen bond donors and hydrogen bond acceptors and then heating in a water bath. Adding rosin amine to the deep eutectic solvent yields a rosin amine-based deep eutectic solvent.

5. The preparation method according to claim 4, characterized in that, The water bath heating temperature is 70-80℃, and the duration is 1-2 hours.

6. The application of a rosin amine compounded deep eutectic solvent corrosion inhibitor as described in any one of claims 1-3 in carbon dioxide transmission pipelines.

7. The application according to claim 6, characterized in that, The corrosion inhibitor is added to the carbon dioxide delivery pipeline at a concentration of 200–500 ppm.

8. The application according to claim 7, characterized in that, The corrosion inhibition efficiency of the rosin amine compound deep eutectic solvent corrosion inhibitor is over 95%.

9. A method for corrosion protection of a carbon dioxide transmission pipeline, characterized in that, Add the rosin amine compound deep eutectic solvent corrosion inhibitor according to any one of claims 1-3 into the conveying pipeline, wherein the concentration of the corrosion inhibitor is 200-500 ppm.

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