阅读说明：本技术 一种高温酸化缓蚀增效剂及其制备方法和缓蚀组合物 (High-temperature acidification corrosion inhibition synergist, preparation method thereof and corrosion inhibition composition ) 是由 崔仕章 宋新旺 侯云福 崔学章 王黎明 刘小芳 郭鑫 郑志微 丁松松 于 2020-12-11 设计创作，主要内容包括：本申请涉及油田开发技术领域,具体涉及一种高温酸化缓蚀增效剂及其制备方法和缓蚀组合物。本申请通过设计新型的分子结构,合成了一种具有表面活性的新型高温酸化缓蚀增效剂,该缓蚀增效剂既可以以吸附层的方式吸附在金属表面对金属材质的管道、设备等起到缓蚀作用,又可以作为表面活性剂对缓蚀主剂起到增强缓蚀效果的作用；并且,将本申请设计并制备获得的缓蚀增效剂与作为缓蚀主剂的壳聚糖进行复配,增加了壳聚糖的溶解性,提高壳聚糖的吸附缓蚀效果,耐温性好；此外,增效剂和壳聚糖均具有很好的降解性,并且降解后的小分子对环境无污染,是更加绿色环保的油田化学品。(The application relates to the technical field of oilfield development, in particular to a high-temperature acidification corrosion inhibition synergist, a preparation method thereof and a corrosion inhibition composition. The novel high-temperature acidification corrosion inhibition synergist with surface activity is synthesized by designing a novel molecular structure, and the corrosion inhibition synergist can be adsorbed on the metal surface in an adsorption layer manner to play a corrosion inhibition role on pipelines, equipment and the like made of metal materials, and can also be used as a surfactant to play a role in enhancing the corrosion inhibition effect on a main corrosion inhibition agent; in addition, the corrosion inhibition synergist which is designed and prepared by the application is compounded with chitosan which is used as a main corrosion inhibition agent, so that the solubility of the chitosan is increased, the adsorption and corrosion inhibition effects of the chitosan are improved, and the temperature resistance is good; in addition, both the synergist and the chitosan have good degradability, and the degraded micromolecules have no pollution to the environment, so that the chitosan/synergist-containing oil field chemical is more environment-friendly.)

1. A high-temperature acidification corrosion inhibition synergist is characterized in that the high-temperature acidification corrosion inhibition synergist has a structure shown as a formula (I):

in the formula, R₁Is a C6-10 substituent, R₂Is a substituent with 8-12C atoms.

2. The high temperature acidizing corrosion inhibition synergist of claim 1 wherein R is₁Is a saturated straight-chain alkyl group with 6-10 carbon atoms, R₂Is a saturated straight-chain alkyl group with 8-12C atoms.

3. The high-temperature acidification corrosion inhibition synergist according to claim 1 is a light yellow liquid, the viscosity of the high-temperature acidification corrosion inhibition synergist is less than 300mPa.s, and the density of the high-temperature acidification corrosion inhibition synergist is 0.90-0.98 g/ml.

4. A process for the preparation of a high temperature acidizing corrosion inhibition synergist according to any one of the claims 1 to 3 wherein said process comprises the steps of:

the method comprises the following steps: dissolving substituted primary amine and glucose in n-butyl alcohol, reacting for 5-8 h at 40-50 ℃, cooling to room temperature, and separating out white floccule to obtain an intermediate A;

step two: dissolving the intermediate A and the 4-substituted phenol in ethanol, heating to 50-60 ℃, uniformly stirring, adding formaldehyde, heating to 75-80 ℃, performing reflux dehydration reaction for 10-12 h, and performing vacuum dehydration and desolventization after the reaction is finished to obtain the high-temperature acidification corrosion inhibition synergist.

5. The method according to claim 4, wherein in the first step, the substituted primary amine and the glucose are used in a molar ratio of 1.1-1.5: 1; and/or in the second step, the molar ratio of the intermediate A to the 4-substituted phenol to the formaldehyde is (1.3-1.5) to 1 (2-4).

6. A corrosion inhibiting composition comprising a high temperature acidification corrosion inhibition synergist according to any one of claims 1-3 and/or a high temperature acidification corrosion inhibition synergist obtained by the preparation method according to claim 4 or 5, wherein the corrosion inhibiting composition further comprises chitosan as a main corrosion inhibition agent, the chitosan has a deacetylation degree of 75-90% and a viscosity of 50-800 mPa-S.

7. The corrosion inhibiting composition of claim 6, wherein the corrosion inhibiting composition comprises, in weight percent: 0.1-10% of high-temperature acidification corrosion inhibition synergist, 15-40% of chitosan, 1-15% of organic acid, 5-10% of organic alcohol and 0.5-2% of film-forming auxiliary agent.

8. The method of preparing the corrosion inhibiting composition of claim 6 or 7, comprising the steps of:

dissolving the high-temperature acidification corrosion inhibition synergist by using a small amount of water, adding chitosan, stirring and mixing at 50-65 ℃ for 6-8 h, adding a proper amount of water for dilution, adding an organic acid, an organic alcohol and a film-forming assistant, and stirring and mixing at 45-55 ℃ for 2-4 h to obtain the high-temperature acidification corrosion inhibition synergist.

9. Use of a high temperature acidizing corrosion inhibition synergist according to any one of claims 1 to 3 and/or a high temperature acidizing corrosion inhibition synergist prepared by the process according to claim 4 or 5 and/or a corrosion inhibition composition according to claim 6 or 7 and/or a corrosion inhibition composition prepared by the process according to claim 8 in the operation of an acidized oil and gas well at a temperature of not less than 90 ℃.

10. The use according to claim 9, wherein the use is carried out by injecting the acid solution together with hydrochloric acid in an amount of 0.5-5% by mass of the acid solution, wherein the acid solution is hydrochloric acid or earth acid with a mass concentration of 15-28%.

Technical Field

The application relates to the technical field of oilfield development, in particular to a high-temperature acidification corrosion inhibition synergist, a preparation method thereof and a corrosion inhibition composition.

Background

In the tertiary oil recovery construction process, the pipeline, the storage tank and various metal equipment suffer from serious corrosion due to the addition of the acid liquor, so that huge economic loss can be caused, and serious safety accidents can be caused. Corrosion inhibitors play a critical role in preventing corrosion.

The corrosion inhibitor on the market is prepared by single component or compounding a plurality of components, and takes aldehyde ketone amine condensation compound, imidazoline derivative and quinazoline quaternary ammonium salt as main corrosion inhibitors and formaldehyde, alkynol and the like as synergists. However, the corrosion inhibition main agent and the synergist commonly used in the industrial production have high toxicity and high harm to the environment, so that the development of an environment-friendly corrosion inhibitor is urgently needed.

The chitosan is a product obtained by N-deacetylation of chitin, and is a green natural high molecular material. And researches find that the chitosan can form an adsorption layer on the surface of the metal due to a large amount of free groups and heteroatoms with lone pair electrons, so that the corrosion inhibition effect on the metal is realized. However, the solubility of chitosan is poor due to more hydrogen bonds in molecules, so that the corrosion inhibition effect is slow and the effect is weak, and the temperature resistance of the chitosan is poor, so that the application of the chitosan is greatly limited.

Chemical modification of chitosan is commonly used in the prior art to enhance the corrosion inhibition effect of chitosan, for example, patent CN 111748048A. However, the direction of chemically modifying a certain material is too many, the preparation process is complex, the workload is large, and the effect is unknown. However, in the prior art, the green environment-friendly oil field additive with good corrosion inhibition effect can not be obtained from the viewpoint of designing a corrosion inhibition synergist.

Disclosure of Invention

In order to solve the problems, the invention provides a green environment-friendly oil field additive with good corrosion inhibition effect at high temperature from the viewpoint of designing and synthesizing a novel molecular structure.

In one aspect, the present application provides a high temperature acidizing corrosion inhibition synergist having a structure according to formula (I):

wherein R is₁Is a C6-10 substituent, R₂Is a substituent with 8-12C atoms.

The high-temperature acidification corrosion inhibition synergist with the molecular structure introduces a substituted tertiary amine group structure and a glucose structure on alkylphenol molecules, wherein R with a long carbon chain₁And R₂The group can show lipophilicity, and the amido group and the glucose group can show hydrophilicity, so the high-temperature acidification corrosion inhibition synergist has certain surface activity.

And N atoms and more O atoms in the molecules can form coordination bonds with metal ions on the metal surface by providing lone-pair electrons, so that the coordination bonds are adsorbed on the metal surface, the oleophylic end is arranged on the other side, and the molecules play a corrosion inhibition role on the metal in an adsorption layer mode. Namely, the corrosion inhibition synergist provided by the application can show a corrosion inhibition effect when being used alone, and can also be used as a synergist due to the surface activity effect of the corrosion inhibition synergist, so that the corrosion inhibition effect of a main corrosion inhibition agent is enhanced.

In addition, the corrosion inhibition synergist also has good degradability, and degraded micromolecules do not pollute the environment, so that the corrosion inhibition synergist is a more environment-friendly oil field additive.

In one embodiment, R₁And R₂Alternative substituents may be saturated hydrocarbon groups such as alkyl groups, unsaturated hydrocarbon groups such as alkylene groups, substituted alkylphenyl groups, etc., and may be attached to a carbon atom of the substituent by a hydroxy group-OH, a carboxyl group-COOH, etc., wherein R is₁And R₂Preferably a hydrocarbon group, more preferably a saturated alkyl hydrocarbon.

Further, R₁Is a saturated straight-chain alkyl group with 6-10 carbon atoms, R₂Is a saturated straight-chain alkyl group with 8-12C atoms.

In the molecular structure, as the alkyl is an electron-repellent group, the increase of the carbon chain and the increase of the alkyl can improve the electric-repellent effect, so that the electron cloud density on the heteroatom is increased, the formed coordination bond is more stable, the corrosion inhibition efficiency is improved, the thickness of the hydrophobic layer is increased due to the increase of the hydrophobic carbon chain, the diffusion difficulty of metal ions, oxygen molecules and hydrogen molecules is increased, the corrosion inhibition efficiency is improved, and the solubility of the synergist is influenced by the overlong carbon chain, so that the saturated straight-chain alkyl with the carbon atom number can be used as a more preferable technical scheme.

Further, the high-temperature acidification corrosion inhibition synergist is light yellow liquid, the viscosity of the liquid is less than 300mPa.s, and the density of the liquid is 0.90-0.98 g/ml.

On the other hand, the application also provides a preparation method of the high-temperature acidification corrosion inhibition synergist, which comprises the following steps:

the method comprises the following steps: dissolving substituted primary amine and glucose in n-butyl alcohol, reacting for 5-8 h at 40-50 ℃, cooling to room temperature, and separating out white floccule to obtain an intermediate A;

step two: dissolving the intermediate A and the 4-substituted phenol in ethanol, heating to 50-60 ℃, uniformly stirring, adding formaldehyde, heating to 75-80 ℃, performing reflux dehydration reaction for 10-12 h, and performing vacuum dehydration and desolventization after the reaction is finished to obtain the high-temperature acidification corrosion inhibition synergist.

Further, in the first step, the molar ratio of the substituted primary amine to the glucose is 1.1-1.5: 1; and/or in the second step, the molar ratio of the intermediate A, the 4-substituted phenol and the formaldehyde is (1.3-1.5): 1, (2-4).

Optionally, the formaldehyde is 37% formaldehyde solution or paraformaldehyde.

Wherein, the chemical reaction process involved in the preparation process is as follows:

wherein R is₁Is C6-10 alkyl, R₂Is an alkyl group having 8 to 12 carbon atoms.

On the other hand, the application also provides a corrosion inhibition composition which comprises the high-temperature acidification corrosion inhibition synergist and/or the high-temperature acidification corrosion inhibition synergist prepared by the preparation method, wherein the corrosion inhibition composition also comprises chitosan serving as a main corrosion inhibition agent, the deacetylation degree of the chitosan is 75-90%, and the viscosity is 50-800mPa & S.

The application also finds that when the corrosion inhibition synergist is compounded with chitosan serving as a main corrosion inhibition agent, glucose groups on the synergist can generate intermolecular interaction with active groups of the chitosan, so that intramolecular hydrogen bonds of the chitosan are destroyed, the solubility of the chitosan is increased, and the adsorption corrosion inhibition effect of the chitosan is improved. And the oleophylic group in the synergist can also increase the thickness of the adsorption layer, so that the adsorption effect of the hydrophilic group and chitosan on the surface of the metal pipeline wall is stronger.

In addition, the phenol group in the synergist shows weak acidity after being dissolved, and can provide an acidic environment more suitable for the dissolution of chitosan. Therefore, the synergist can obviously improve the corrosion inhibition effect of the chitosan.

Further, the corrosion inhibiting composition comprises, by weight percent: 0.1-10% of high-temperature acidification corrosion inhibition synergist, 15-40% of chitosan, 1-15% of organic acid, 5-10% of organic alcohol and 0.5-2% of film-forming auxiliary agent.

Preferably, the organic acid is selected from formic acid or acetic acid; the organic alcohol is selected from one or more of ethanol, propanol, isopropanol, butanol, isobutanol or ethylene glycol; the film forming assistant is one or more selected from glycol decamethylene, propylene glycol ethyl ether, propylene glycol butyl ether and dipropylene glycol monomethyl ether.

Preferably, the balance of the above composition is made up with deionized water.

In another aspect, the present application also provides a method for preparing the corrosion inhibiting composition, comprising the following steps:

dissolving the high-temperature acidification corrosion inhibition synergist by using a small amount of water, adding chitosan, stirring and mixing at 50-65 ℃ for 6-8 h, adding a proper amount of water for dilution, adding an organic acid, an organic alcohol and a film-forming assistant, and stirring and mixing at 45-55 ℃ for 2-4 h to obtain the high-temperature acidification corrosion inhibition synergist.

On the other hand, the application also provides the high-temperature acidification corrosion inhibition synergist, and/or the high-temperature acidification corrosion inhibition synergist prepared by the preparation method, and/or the corrosion inhibition composition, and/or the application of the corrosion inhibition composition prepared by the preparation method in the operation of an acidified oil-gas well, wherein the temperature of the acidified oil-gas well is not lower than 90 ℃.

Optionally, the corrosion inhibiting compositions provided herein can provide corrosion inhibition at temperatures of 90 ℃, 120 ℃, 160 ℃, or even 180 ℃.

Further, when in use, the acid solution is injected together with the acid solution, the using amount of the acid solution is 0.5-5% of the mass of the acid solution, and the acid solution is hydrochloric acid or earth acid with the mass concentration of 15-28%.

The following beneficial effects can be brought through the application:

1. the novel high-temperature acidification corrosion inhibition synergist with surface activity is prepared and synthesized by designing a novel molecular structure, can be adsorbed on the metal surface in an adsorption layer manner to play a corrosion inhibition role on pipelines, equipment and the like made of metal materials, and can also be used as a surfactant to play a role in enhancing the corrosion inhibition effect on a main corrosion inhibition agent;

2. according to the corrosion inhibition composition, the corrosion inhibition synergist which is designed and prepared in the application is compounded with chitosan serving as a main corrosion inhibition agent, so that the solubility of the chitosan is increased, the adsorption corrosion inhibition effect of the chitosan is improved, and other auxiliary agents are compounded to obtain the corrosion inhibition composition which can resist the high temperature of 180 ℃ at most;

3. in the corrosion inhibition composition provided by the application, both the synergist and the chitosan have good degradability, and degraded micromolecules have no pollution to the environment, so that the corrosion inhibition composition is a more environment-friendly oilfield chemical.

Detailed Description

In order to more clearly explain the overall concept of the present application, the following detailed description of the overall scheme of the present invention is made by way of example. In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring the invention.

Unless otherwise specified, the starting components in the examples below are commercially available, and the laboratory instruments used are laboratory conventional laboratory instruments and the performance testing methods are those known in the art.

Example 1

The embodiment provides a high-temperature acidification corrosion inhibition synergist, which is prepared by the following method:

the method comprises the following steps: 2.631g (26mmol) of n-hexylprimary amine is dissolved in 50ml of n-butyl alcohol, 3.637g (20mmol) of anhydrous glucose is added, the mixture is uniformly mixed by magnetic stirring, the mixture is heated to 50 ℃ under the condition of water bath and reacts for 5 to 8 hours, the mixture is cooled after the reaction is finished, and is placed at the low temperature of 4 ℃ for standing for 12 hours, and a large amount of white floccules are separated out, namely an intermediate A;

step two: dissolving 0.05mol of 4-n-nonylphenol in 100ml of ethanol, adding 0.07mol of the intermediate A, magnetically stirring to mix and dissolve the intermediate A, heating to 55 ℃ and keeping for 30min, dropwise adding 37% formaldehyde solution, wherein the dropwise adding amount is 3 times of the molar amount of the nonylphenol, after the dropwise adding is finished, continuously heating to 79 ℃ to perform reflux dehydration reaction for 10-12 h, and after the reaction is finished, performing dehydration and solvent removal under a vacuum condition to obtain the high-temperature acidification corrosion inhibition synergist.

The high-temperature acidification corrosion inhibition synergist obtained by the method has the following chemical formula:

the appearance of the high-temperature acidification corrosion inhibition synergist is light yellow liquid, and according to the relevant standard of liquid petrochemical products, the viscosity of the high-temperature acidification corrosion inhibition synergist is about 200mPa.s, the density of the high-temperature acidification corrosion inhibition synergist is 0.96g/ml, and the solid content of the high-temperature acidification corrosion inhibition synergist is more than or equal to 98%.

Examples 2 to 6

Examples 2 to 6 each provide a high-temperature acidification corrosion inhibition synergist, which is prepared by the same method as in example 1, except that the type of alkyl primary amine used in the first step and the type of alkyl phenol used in the second step are different, and all satisfy the following general formula:

wherein R is₁Selected from saturated straight chain hydrocarbon alkyl with 6-10 carbon atoms, R₂Selected from saturated straight chain hydrocarbon alkyl with 8-12 carbon atoms. In addition, the high-temperature acidification corrosion inhibition synergist prepared in the embodiment 2-6 is addedThe appearance and the character are all yellow liquid, and according to the relevant standard of liquid petrochemical products, the density of the corrosion inhibition synergist of each embodiment is measured to be 0.90-0.98 g/ml, the viscosity is less than 300mPa.s, the solid content is more than or equal to 98%, and the yield is 80-94%.

And (3) determination of corrosion inhibition performance:

the slow release performance of the corrosion inhibitor in each embodiment is inspected by a weight loss method, and the specific test method is as follows: soaking an oil-free packaged N80 carbon steel sheet in absolute ethyl alcohol for 10min, wiping the steel sheet with absorbent cotton, drying the steel sheet in a dryer to constant weight after cold air blow drying, and accurately weighing the steel sheet to 0.0001 g. The corrosion test is carried out in a water bath kettle at a constant temperature of 90 ℃ for 4h by taking 20% hydrochloric acid as a corrosion medium and putting the N80 carbon steel sheet into the corrosion medium containing the corrosion inhibitor and a blank acid solution. After the corrosion test is finished, the carbon steel sheet is wiped by distilled water and absolute ethyl alcohol, then is dried in vacuum to constant weight, is weighed, calculates the corrosion inhibition rate according to the mass data of the carbon steel sheet before and after corrosion and the surface area of the carbon steel sheet, and carries out scanning electron microscope test on a test sample to observe the surface morphology. Blank controls without any corrosion inhibitors were set, with commercially available cycloalkylimidazoline corrosion inhibitors as positive controls, and each example corrosion inhibitor was formulated with deionized water to a concentration of 100 ppm. In the specific examples R₁And R₂See table 1 for the choices of (d), and the results of the tests.

TABLE 1

As can be seen from the data in Table 1, the corrosion inhibition synergist provided by the application has a corrosion inhibition rate and a corrosion inhibition rate which are slightly different from those of the commercial corrosion inhibitors, so that the corrosion inhibition synergist can play a good corrosion inhibition role on metals when being used alone. At the same time, R₁And R₂The length of the carbon chain of the two groups has certain influence on the corrosion inhibition effect, and when the carbon chain is shorter, the hydrophobic partThe electricity repulsion is insufficient, and the adhesive force of the adsorption layer is not strong; when the carbon chain is longer, the solubility is reduced at the same dosage concentration, and the adhesion effect is limited.

Examples 7 to 10

The embodiment provides a corrosion inhibition composition, which comprises the following components in percentage by weight:

8 percent of high-temperature acidification corrosion inhibition synergist, 35 percent of chitosan (the deacetylation degree of the chitosan is 85 percent, and the viscosity is 100 mPa.S), 12 percent of acetic acid, 6 percent of isopropanol, 1 percent of decaglycol ester, and the balance of deionized water.

Wherein, the corrosion inhibition synergist in the embodiments 1-4 is compounded with chitosan, and then the compounded composition is prepared with the organic acid, the organic alcohol, the film forming assistant and the deionized water with the same components and dosage to obtain embodiments 7-10, and the corrosion inhibition performance of the series of compositions is tested. The corrosion inhibition performance test still takes 20% hydrochloric acid as a corrosion medium, adopts N80 carbon steel to corrode the coupon for 4 hours at different temperatures, the mass of the added composition agent is 1% of the mass of the acid corrosion medium solution, and still sets a blank control example without any corrosion inhibitor, a commercially available naphthenic imidazoline corrosion inhibitor (43%) is adopted to replace a high-temperature acidification corrosion inhibition synergist (8%) and chitosan (35%) in the composition as a positive control, and the composition without any corrosion inhibition synergist in the example is used as D1. In the specific examples R₁Group and R₂The choice of groups, as well as the test results, are shown in table 2.

TABLE 2

The data in table 2 show that the corrosion inhibition effect of chitosan used alone is not as good as that of the commonly-used commercially-available corrosion inhibitor, but after the chitosan is compounded with the acidification corrosion inhibition synergist provided by the application, the corrosion inhibition rate and the corrosion inhibition effect are remarkably improved, the high temperature resistance is shown, and the corrosion inhibition rate at 180 ℃ can still reach over 79%. From the foregoing, although the synergist provided by the present application shows a good corrosion inhibition effect when used alone, the corrosion inhibition effect is still weaker than that of a commercially available imidazoline corrosion inhibitor, however, the corrosion inhibition composition after being compounded shows a corrosion inhibition effect which is significantly better than that of a commercially available corrosion inhibitor, so that the corrosion inhibition synergist provided by the present application and the corrosion inhibition effect of a chitosan corrosion inhibition main agent have an obvious synergistic improvement effect when chitosan is used as a main corrosion inhibitor.

In conclusion, the high-temperature acidification corrosion inhibition synergist provided by the application can show a good corrosion inhibition effect when used alone or compounded with other main corrosion inhibitors, particularly can show a synergistic effect when compounded with unmodified chitosan, and can resist a high temperature of 180 ℃ at most. Meanwhile, in the corrosion inhibition composition provided by the application, both the synergist and chitosan have good degradability, and degraded small molecules have no pollution to the environment, so that the corrosion inhibition composition is a more environment-friendly oilfield chemical compared with the existing industrial product.

The above description is only an example of the present application and is not intended to limit the present application. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.