An environment-friendly oil corrosion inhibitor, its preparation method and uses

Abstract

The present invention provides an environment-friendly oil corrosion inhibitor, its preparation method and uses. The environment-friendly oil corrosion inhibitor of the present invention is characterized by comprising the following components in parts by weight: 2-10 parts of polybasic acid; 1-5 parts of organic base; 30-50 parts of organic solvent; 10-30 parts of water. The present invention also discloses the preparation method of the environment-friendly oil corrosion inhibitor and its uses in the field of oil corrosion inhibition. The environment-friendly oil corrosion inhibitor of the present invention can protect metals and prevent metal corrosion.

Description

Technical Field

[0001] The present invention relates to the technology of corrosion inhibitors, and particularly to an environment-friendly oil corrosion inhibitor, a preparation method thereof, and uses thereof. Background Art

[0002] In the production of the oil and gas industry, metal corrosion is a crucial problem. To slow down or prevent metal corrosion, corrosion inhibitors are usually added to the environmental medium to protect the metal. This method has the characteristics of being easy to use and cost-saving, and has become one of the important methods for preventing metal corrosion.

[0003] During the petroleum production process, some corrosion inhibitors are usually added to the corrosive medium. The corrosion inhibitor can delay the corrosion of metal and metal alloy equipment by forming a protective film on the metal surface, prevent the damage of the equipment, and thus increase the service life of the equipment. Operating in this way is simple, with quick results, simple dosing, low cost, and strong applicability.

[0004] The existing corrosion inhibitors have poor corrosion inhibition effects and will affect the activity of the catalyst to a certain extent during use. Moreover, the use of quaternary ammonium salts and organic polymer corrosion inhibitors affects the production efficiency of enterprises and increases the production costs of enterprises. Therefore, it is necessary to develop an environment-friendly oil corrosion inhibitor that can effectively protect metals, has good environmental protection performance, and does not generate harmful gases. Summary of the Invention

[0005] The object of the present invention is to propose an environment-friendly oil corrosion inhibitor aiming at the problems of poor corrosion inhibition effect, low production efficiency, high cost, etc. of the existing oil corrosion inhibitors. This corrosion inhibitor can effectively protect metals, has good environmental protection performance, and does not generate harmful gases.

[0006] To achieve the above object, the technical solution adopted by the present invention is: an environment-friendly oil corrosion inhibitor, comprising the following components in weight ratios:

[0007]

[0008]

[0009] Further, the polybasic acid is an organic acid.

[0010] Further, the polybasic acid is an organic acid, and its function is to maintain the acidity of the system and provide necessary hydrogen ions for the reaction.

[0011] Further, the polybasic acid is preferably one or more of suberic acid, azelaic acid, citric acid, tartaric acid, adipic acid.

[0012] Further, the polybasic acid is most preferably suberic acid.

[0013] Further, the acid is 5-9 parts.

[0014] Further, the organic base is an alkanolamine compound.

[0015] Further, the organic base is preferably one or more of N-methylmonoethanolamine, N,N-diethylethanolamine, N-methyldiethanolamine, isopropanolamine, diethanolamine, 3-amino-1-propanol, 2-amino-1-butanol.

[0016] Further, the organic base is most preferably N,N-diethylethanolamine.

[0017] Further, the organic base is 3-5 parts.

[0018] Further, the weight ratio of the polybasic acid to the organic base is 10:1-1:1.

[0019] Further, the weight ratio of the polybasic acid to the organic base is preferably 5:1-2:1.

[0020] Further, the weight ratio of the polybasic acid to the organic base is most preferably 3:1.

[0021] On the one hand, the organic base can increase the steric hindrance and slow down the metal corrosion rate; on the other hand, the organic base contains lone pair electrons, has an electron-withdrawing property and is electronegative, and adsorbs with the electropositive property presented by the metal, so as to adsorb on the metal surface and prevent metal corrosion.

[0022] Further, the organic solvent is heterocyclic and straight-chain.

[0023] Further, the heterocyclic organic solvent is one or more of toluene, xylene, phenol, benzyl alcohol, phenethyl alcohol.

[0024] Further, the straight-chain organic solvent is one or more of methanol, ethanol, n-propanol, ethylene glycol, propylene glycol, glycerol, acetone.

[0025] Further, the organic solvent is most preferably phenol and acetone.

[0026] Further, the mass ratio of the heterocyclic organic solvent to the straight-chain organic solvent is 10:1-1:1.

[0027] Further, the mass ratio of the heterocyclic organic solvent to the straight-chain organic solvent is preferably 4:1-1:1.

[0028] Further, the mass ratio of the heterocyclic organic solvent to the straight-chain organic solvent is most preferably 2:1.

[0029] Further, the organic solvent is 30-40 parts.

[0030] Further, the water is deionized water with a resistance ≥ 18 MΩ.

[0031] Further, the amount of the water is 20 - 30 parts.

[0032] Another object of the present invention also discloses a preparation method of an environment-friendly oil corrosion inhibitor, comprising the following steps:

[0033] Step 1: Weigh each component according to the weight ratio.

[0034] Step 2: Place the water in a container, add an organic solvent, stir evenly, then add an organic base while stirring, stir evenly, add a polybasic acid, and stir evenly to obtain the environment-friendly oil corrosion inhibitor.

[0035] Further, in Step 2: Place the water in a container, add an organic solvent, stir at a speed of 80 - 100 r / min for 5 - 10 min, add an organic base while stirring, stir for 10 - 15 min, add a polybasic acid, and stir for 5 - 10 min to obtain the environment-friendly oil corrosion inhibitor.

[0036] Another object of the present invention also discloses the use of an environment-friendly oil corrosion inhibitor in the field of metal protection.

[0037] The environment-friendly oil corrosion inhibitor and its preparation method of the present invention have the following advantages compared with the prior art:

[0038] 1. The present invention uses an organic base to increase the steric hindrance and slow down the metal corrosion rate; on the other hand, the organic base contains lone pair electrons, is electron-withdrawing and electronegative, and adsorbs with the electropositive nature of the metal, thereby adsorbing on the metal surface to prevent metal corrosion.

[0039] 2. The present invention uses a long-chain polybasic acid to be compounded with an organic base, adjusts the weight ratio of the two to control the pH value of the corrosion inhibitor, and further improves the metal corrosion inhibition ability.

[0040] 3. The present invention simultaneously introduces a heterocyclic organic solvent and a straight-chain organic solvent, further promotes the adsorption of the corrosion inhibitor on the metal surface to form a protective film, and enhances the solubility of the corrosion inhibitor system.

[0041] 4. The preparation process of the environment-friendly oil corrosion inhibitor of the present invention is simple, has no special requirements for subsequent processes, and is easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a scanning electron microscope picture of a metal test piece magnified 10,000 times after being corroded by the corrosion inhibitor of Example 1;

[0043] Figure 2Scanning electron microscope image of a metal specimen after corrosion with the corrosion inhibitor of Comparative Example 1, magnified 10,000 times. Detailed implementation manners

[0044] The present invention will be further described below in conjunction with embodiments:

[0045] Embodiments 1-10

[0046] Embodiments 1-10 of the present invention disclose a variety of environmentally friendly oil corrosion inhibitors. The components and weight ratios thereof are shown in Table 1. The preparation of the environmentally friendly oil corrosion inhibitor includes the following steps:

[0047] Step 1: Weigh each component according to the weight ratio.

[0048] Step 2: Place water in a container, add an organic solvent, stir at a speed of 90 r / min for 8 min, add an organic base while stirring, after stirring for 12 min, add a polybasic acid, and after stirring for 8 min, the environmentally friendly oil corrosion inhibitor can be obtained.

[0049] Table 1 Components and weight ratios of the environmentally friendly oil corrosion inhibitors in Embodiments 1-10

[0050]

[0051] Comparative Examples 1-4

[0052] Comparative Examples 1-4 disclose a variety of corrosion inhibitors. The components and weight ratios thereof are shown in Table 2. The preparation method is the same as that of Example 1.

[0053] Table 2 Components and weight ratios of the corrosion inhibitors in Comparative Examples 1-4

[0054]

[0055] Corrosion experiments were carried out using the environmentally friendly oil corrosion inhibitors of Embodiments 1-10 and the corrosion inhibitors of Comparative Examples 1-4. The weight change of the metal specimens was measured, and the weight loss rate was calculated. The test method is as follows:

[0056] Weight loss rate test: Immerse the metal specimens into the corrosion inhibitors of the embodiments or comparative examples (100 mL) respectively, seal them with plastic wrap, heat them in a water bath to 60 °C, take out the specimens after 300 min, weigh the mass of the metal specimens before and after immersion 3 times with an analytical balance, and take the average value of the three weighings as the mass of the specimen. The weight loss rate = (mass before immersion - mass after immersion) / mass before immersion * 100%.

[0057] Table 3 shows the test results of the environmentally friendly oil corrosion inhibitors of Embodiments 1-10 and the corrosion inhibitors of Comparative Examples 1-4. It can be seen that the weight loss rate of the embodiments is lower than that of the comparative examples, the corrosion of the metal is weaker, and the metal can be better protected.

[0058] Table 3 Test Results of Examples 1-10 and Comparative Examples 1-4

[0059]

[0060]

[0061] The metal specimens were immersed in the corrosion inhibitors of Example 1 and Comparative Example 1 for corrosion (corrosion for 300 min at 60 °C), and the corrosion results are as Figure 1 and 2 shown. Figure 1 is a scanning electron microscope image of the metal specimen after corrosion with the corrosion inhibitor of Example 1 magnified 7000 times; Figure 2 is a scanning electron microscope image of the metal specimen after corrosion with the corrosion inhibitor of Comparative Example 1 magnified 7000 times. It can be seen from Figure 1 that the surface of the metal specimen immersed in Example 1 is flat and basically not corroded, indicating that the corrosion inhibitor of Example 1 has a high corrosion inhibition effect on the metal. And it can be seen from Figure 2 that the metal specimen has been severely corroded into white flocs, indicating that the corrosion inhibitor of Comparative Example 1 has a poor corrosion inhibition effect on the metal.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An environment-friendly oil corrosion inhibitor, characterized in that, It is composed of the following components in the following weight ratios: The polybasic acid is suberic acid; The organic base is N,N-diethylethanolamine; The weight ratio of the polybasic acid to the organic base is 3:1; The organic solvent is phenol and acetone, and the mass ratio of phenol to acetone is 2:

1.

2. A preparation method of the environment-friendly oil corrosion inhibitor according to claim 1, characterized in that, It includes the following steps: Step 1: Weigh each component according to the weight ratio; Step 2: Place water in a container, add the organic solvent, stir evenly, then add the organic base while stirring, stir evenly, add the polybasic acid, and stir evenly to obtain an environmentally friendly oil corrosion inhibitor.

3. Use of the environment-friendly oil corrosion inhibitor according to claim 1 in the field of oil corrosion inhibition.

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