阅读说明：本技术 一种基于苯并咪唑衍生物的缓蚀剂及其制备方法和应用 (Corrosion inhibitor based on benzimidazole derivative and preparation method and application thereof ) 是由 辛格 于 2019-10-30 设计创作，主要内容包括：本发明属于油井酸化模拟技术领域,公开了一种基于苯并咪唑衍生物的缓蚀剂及其制备方法和应用,按照摩尔比2-(4-甲氧基苯基)-1H苯并咪唑：2-苯基-1H-苯并咪唑＝1:1。在圆底烧瓶中按照2-(4-甲氧基苯基)-1H苯并咪唑:和2-苯基-1H-苯并咪唑以1:1的摩尔比合成苯并咪唑衍生物；室温刺激芳香醛2mol、邻苯二胺2mol、硼酸0.1g和水1ml,15-30min；反应结束后加入水5ml,再搅拌10min,得到沉淀物；从乙醇中过滤和再结晶E。本发明不破坏人体,符合绿色化学的价值观；效率高、缓蚀效果好、使用浓度低的；缓蚀效果达95％以上；原料价廉易得,成本低廉。缓蚀剂具有生物和药物活性。(The invention belongs to the technical field of oil well acidification simulation, and discloses a benzimidazole derivative-based corrosion inhibitor, and a preparation method and application thereof, wherein the benzimidazole derivative-based corrosion inhibitor is prepared from 2- (4-methoxyphenyl) -1H benzimidazole in a molar ratio: 2-phenyl-1H-benzimidazole ═ 1: 1. Synthesizing a benzimidazole derivative in a round bottom flask according to 2- (4-methoxyphenyl) -1H-benzimidazole and 2-phenyl-1H-benzimidazole in a molar ratio of 1: 1; stimulating 2mol of aromatic aldehyde, 2mol of o-phenylenediamine, 0.1g of boric acid and 1ml of water at room temperature for 15-30 min; after the reaction is finished, adding 5ml of water, and stirring for 10min to obtain a precipitate; e was filtered and recrystallized from ethanol. The invention does not damage human body and accords with the value view of green chemistry; the efficiency is high, the corrosion inhibition effect is good, and the use concentration is low; the corrosion inhibition effect reaches more than 95 percent; the raw materials are cheap and easily available, and the cost is low. The corrosion inhibitor has biological and pharmaceutical activity.)

1. A corrosion inhibitor based on a benzimidazole derivative, characterized in that the corrosion inhibitor based on the benzimidazole derivative consists of 2- (4-methoxyphenyl) -1H-benzimidazole and 2-phenyl-1H-benzimidazole according to a molar ratio; 2- (4-methoxyphenyl) -1H benzimidazole: 2-phenyl-1H-benzimidazole ═ 1: 1.

2. A method for preparing the benzimidazole derivative-based corrosion inhibitor according to claim 1, wherein the method comprises the following steps:

a first step of synthesizing a benzimidazole derivative in a round-bottom flask according to 2- (4-methoxyphenyl) -1H-benzimidazole and 2-phenyl-1H-benzimidazole in a molar ratio of 1: 1;

secondly, stimulating aromatic aldehyde, o-phenylenediamine, boric acid and water at room temperature for 15-30 min;

step three, adding water after the reaction is finished, and stirring again to obtain a precipitate; e was filtered and recrystallized from ethanol.

3. The method for preparing a benzimidazole derivative-based corrosion inhibitor according to claim 2, wherein the second step stimulates 2mol of aromatic aldehyde, 2mol of o-phenylenediamine, 0.1g of boric acid and 1ml of water at room temperature for 15-30 min.

4. The method for preparing the benzimidazole derivative-based corrosion inhibitor according to claim 2, wherein 5ml of water is added after the reaction of the third step is completed, and the mixture is stirred for 10min to obtain a precipitate; e was filtered and recrystallized from ethanol.

5. The method of preparing the benzimidazole derivative-based corrosion inhibitor according to claim 2, wherein the benzimidazole derivative-based corrosion inhibitor is prepared by reacting two benzimidazole derivatives, which are synthesized as inhibitors of 2- (4-methoxyphenyl) -1H-benzimidazole and 2-phenyl-1H-benzimidazole on N80 steel, with piperidine to form the structural formula of the formula:

6. use of a benzimidazole derivative-based corrosion inhibitor according to claim 1 in oil well simulation.

7. Use of a benzimidazole derivative-based corrosion inhibitor according to claim 1 for the acidification of oil wells.

Technical Field

The invention belongs to the technical field of oil well acidification simulation, and particularly relates to a benzimidazole derivative-based corrosion inhibitor, and a preparation method and application thereof.

Background

Currently, the closest prior art: the prior art mainly adopts an ammonification and emulsion polymerization method, and the method has the defects that an emulsifier in a system is not easy to remove, and the defects are caused by using an oxidant with lower oxidability as an initiator in the emulsion polymerization process. In oil production technology, well simulation or acidizing is typically the introduction of an acidic solution into a well at high pressure. Thermal decomposition leads to a decrease in corrosion inhibitor performance as well depth increases. To collect the effect of temperature increase on the corrosion rate of N80 steel in 15% HCl at 30, 50, 70, and 90 ℃, the effect of temperature increase on the corrosion rate of N80 steel without BZs and at the optimal BZs concentration was investigated. The use of the arrhenius equation, which is known as the corrosion rate versus temperature and expressed in terms of the corrosion rate versus 1/t logarithm, shows that the organic compounds used as effective corrosion inhibitors during acidification are mainly acetols.

In summary, the problems of the prior art are as follows: the prior art adopts an ammoniation and emulsion polymerization method, so that the intermediate steps are more, the produced pollutants are more, and the additive is not easy to remove.

The difficulty of solving the technical problems is as follows: the corrosion inhibitor is synthesized directly on the basis of imidazole derivatives.

The significance of solving the technical problems is as follows: in order to solve the problem of serious corrosion of equipment pipelines caused by oilfield sewage, an economical and practical method for synthesizing the corrosion inhibitor is provided in the oilfield sewage treatment process.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a benzimidazole derivative-based corrosion inhibitor and a preparation method and application thereof.

The invention is realized by that, the corrosion inhibitor based on the benzimidazole derivative, the corrosion inhibitor based on the benzimidazole derivative consists of 2- (4-methoxyphenyl) -1H benzimidazole and 2-phenyl-1H-benzimidazole according to molar ratio, wherein the corrosion inhibitor is a chemical substance or a mixture of several chemical substances which can prevent or slow down corrosion when existing in an environment (medium) in proper concentration and form, and is characterized in that the corrosion speed of a metal material in the medium can be obviously reduced to zero by adding a trace amount or a small amount of the chemical substances, and the original physical and mechanical properties of the metal material can be kept unchanged; 2- (4-methoxyphenyl) -1H benzimidazole: 2-phenyl-1H-benzimidazole ═ 1: 1.

Another object of the present invention is to provide a method for preparing the benzimidazole derivative-based corrosion inhibitor, which comprises the following steps:

a first step of synthesizing a benzimidazole derivative in a round-bottom flask according to 2- (4-methoxyphenyl) -1H-benzimidazole and 2-phenyl-1H-benzimidazole in a molar ratio of 1: 1;

secondly, stimulating 2mol of aromatic aldehyde, 2mol of o-phenylenediamine, 0.1g of boric acid and 1ml of water at room temperature for 15-30 min;

step three, adding 5ml of water after the reaction is finished, and stirring for 10min to obtain a precipitate; e was filtered and recrystallized from ethanol.

Further, the preparation method of the benzimidazole derivative based corrosion inhibitor comprises the step of reacting two benzimidazole derivatives, which are synthesized inhibitors of 2- (4-methoxyphenyl) -1H benzimidazole and 2-phenyl-1H-benzimidazole on N80 steel as corrosion inhibitors, with piperidine to form a structural formula of a molecular formula:

another object of the present invention is to provide a use of the benzimidazole derivative-based corrosion inhibitor in oil well simulation.

Another object of the present invention is to provide a use of the benzimidazole derivative-based corrosion inhibitor in oil well acidizing.

In summary, the advantages and positive effects of the invention are: the invention adopts two synthesized benzimidazole derivatives (BZS) as N80 steel corrosion inhibitors in 15% HCl corrosion environment at the temperature of 30-90 ℃, and the corrosion inhibition potential is researched by methods such as electrochemistry, gravimetric analysis, surface screening and the like. BZS is a good corrosion inhibitor at 30 ℃, but the corrosion inhibition effect is weak at high temperature. Gibbs free energy and adsorption enthalpy indicate that BZS is adsorbed on metal surfaces primarily by physical action. The adsorption of BZS on the surface of N80 steel was confirmed with Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM).

The invention takes BZS as a basic component, adds additives such as potassium iodide, SDS, N-acetylcysteine and the like, and develops four different BZS formulas. The corrosion inhibition performance of the four formulas is examined under different experimental temperatures and compared with the corrosion inhibitor sold in the market. The results show that the BZS-based formulations (F4BZ-1 and F4BZ-2) compete with commercial corrosion inhibitors even at high temperatures; the commercial corrosion inhibitor has a corrosion inhibition efficiency of 95.46% at 90 ℃, while the corrosion inhibition efficiencies of F4BZ-1 and F4BZ-2 are 92.94% and 90.61%, respectively.

The corrosion inhibitor provided by the invention is simulated by using Material Studio software, and the result shows that the organic corrosion inhibitors can be adsorbed on the metal surface through different substituents and have higher adsorption capacity on the iron surface, thereby achieving the purpose of inhibiting corrosion and improving the corrosion inhibition effect and efficiency. The hydrochloric acid solution carries an excessive positive charge on the steel surface. Therefore, the hydrated chloride ions on the positively charged metal surface are adsorbed on the solution side to generate excessive negative charges, which is beneficial to the adsorption of corrosion inhibitor molecules on the iron surface. In addition, the interaction between the p electron in the BZ-1 molecule and the iron atom vacancy d can also be adsorbed on the iron surface, thereby inhibiting the occurrence of corrosion. In addition, the delocalization of P electron is enhanced by the presence of an electron donating group (-OCH3), and the adsorption ability of BZ-1 is improved.

The invention not only considers the change of the temperature field of the shaft, but also considers the factors of the filtration loss of acid liquor, the change of reaction activation energy and the like. More technical problems are involved, the technical scheme is considered more thoroughly, and the obtained technical effect is better. Compared with the prior art, the invention does not damage human body and accords with the value view of green chemistry. The corrosion inhibitor has the advantages of high efficiency, good corrosion inhibition effect and low use concentration, and the corrosion inhibition effect reaches more than 95%. The raw materials of the corrosion inhibitor are cheap and easy to obtain, and the cost is low. The corrosion inhibitor has wide biological and pharmaceutical activity. The corrosion inhibitor contains organic matter components which are composed of polar groups with corrosion inhibition effect and other nonpolar groups, wherein most of the polar groups contain O, N, S and other heteroatoms with lone pair electrons. Therefore, he is said to have biological and pharmaceutical activity.

Drawings

FIG. 1 is a flow chart of a method for preparing a corrosion inhibitor based on benzimidazole derivatives according to an embodiment of the present invention.

FIG. 2 is a graphical illustration of corrosion rate and inhibition rate as a function of concentration and temperature provided by an embodiment of the present invention;

in the figure: (a) the corrosion rate varies with concentration; (b) inhibition efficiency as a function of concentration; (c) suppressing the variation of efficiency with temperature.

Fig. 3 is an arrhenius curve of Corrosion Rate (CR) of N80 steel in 15% HCl (no BZs and optimal concentration with BZs present) provided by an embodiment of the present invention.

Figure 4 is a graphical representation of the langmuir thermal curve of the adsorption inhibitor provided by the examples of the present invention as a function of ln-Kads vs T adsorption to BZs on N80 steel;

in the figure: (a) langmuir thermal profile of adsorption inhibitor; (b) ln-Kads adsorbed by BZs on N80 steel correlates with T.

FIG. 5 is a Nyquist plot of the absence and presence of different concentrations BZs and an equivalent circuit schematic diagram of use provided by an embodiment of the present invention;

in the figure; (a) nyquist plots of different concentrations BZs were not present; (b) nyquist plots of different concentrations BZs exist; (c) an equivalent circuit is used.

FIG. 6 is a BODE plot in the absence and presence of a different concentration BZs versus phase angle plot in the absence and presence of a different concentration BZs as provided by an embodiment of the present invention;

in the figure: (a) BODE plots lacking different concentrations BZs; (b) BODE plots of different concentrations BZs exist; (c) phase angle plots in the absence of different concentrations BZs; (d) phase angle plots at different concentrations BZs.

Fig. 7 is a graph illustrating the dynamic polarization curves of potentials in the absence and presence of various concentrations BZs provided by an embodiment of the present invention.

FIG. 8 is an electrochemical frequency modulation plot of N80 steel provided by an embodiment of the present invention;

in the figure: (a) blank; (b) electrochemical frequency modulation diagram of N80 steel in BZ-1; (c) electrochemical frequency modulation of N80 steel in BZ-2.

FIG. 9 is a schematic diagram of intermodulation spectrum of N80 steel provided by an embodiment of the present invention;

in the figure: (a) a blank; (b) intermodulation spectrum of N80 steel in BZ-1; (c) intermodulation spectrum of N80 steel in BZ-2.

FIG. 10 is a schematic view of a scanning electron microscope image of N80 steel provided by an embodiment of the present invention;

in the figure: (a) a blank; (b) scanning electron microscope images of N80 steel in BZ-2; (c) scanning electron microscope images of N80 steel in BZ-1.

FIG. 11 is a schematic representation of an AFM image of N80 steel provided by an embodiment of the present invention;

in the figure: (a) blank; (b) AFM images of N80 steel in BZ-2; (c) AFM images of N80 steel in BZ-1.

FIG. 12 is a schematic diagram of roughness peaks provided by an embodiment of the present invention;

in the figure: (a) blank; (b) peak roughness obtained for BZ-2; (c) peak roughness obtained for BZ-1.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Aiming at the problems in the prior art, the invention provides a benzimidazole derivative-based corrosion inhibitor, a preparation method and application thereof, and the Benzimidazole (BZS) derivative is used as an N80-grade corrosion inhibitor for oilfield steel. In order to simulate the corrosion of oil fields in the laboratory, a hydrochloric acid concentration of 15% is usually adopted in the acidification process; BZS was used as an alkaline/active corrosion inhibitor and effective corrosion inhibitor formulations were developed incorporating some known additives. Finally, the developed corrosion inhibitor formulation was compared to the commercial corrosion inhibitors. The present invention will be described in detail below with reference to the accompanying drawings.

The corrosion inhibitor based on the benzimidazole derivative provided by the embodiment of the invention is prepared by mixing the following components in a molar ratio of 2- (4-methoxyphenyl) -1H benzimidazole (BZ-1): 2-phenyl-1H-benzimidazole (BZ-2) ═ 1: 1.

As shown in fig. 1, a preparation method of a corrosion inhibitor based on a benzimidazole derivative provided by an embodiment of the invention includes the following steps:

s101: synthesizing a benzimidazole derivative in a round bottom flask according to 2- (4-methoxyphenyl) -1H-benzimidazole and 2-phenyl-1H-benzimidazole in a molar ratio of 1: 1;

s102: stimulating 2mol of aromatic aldehyde, 2mol of o-phenylenediamine, 0.1g of boric acid and 1ml of water at room temperature for 15-30 min;

s103: after the reaction is finished, adding 5ml of water, and stirring for 10min to obtain a precipitate; e was filtered and recrystallized from ethanol.

According to the corrosion inhibitor based on the benzimidazole derivative provided by the embodiment of the invention, two benzimidazole derivatives which are synthesized as the inhibitors, namely 2- (4-methoxyphenyl) -1H benzimidazole (BZ-1) and 2-phenyl-1H-benzimidazole (BZ-2), react with a small amount of piperidine on N80 steel to form a structural formula of a molecular formula:

TABLE 1 thermodynamic parameters for corrosion inhibitor adsorption of N80 steel in 15% HCl with BZs and without BZs

TABLE 2 electrochemical resistance parameters of N80 steel in the presence of different concentrations BZs at 308K in 15% HCl

TABLE 3 electrochemical polarization parameters of N80 steel in the presence of different concentrations Bzs at 308K in 15% M HCl

TABLE 4 electrochemical frequency modulation parameters of N80 steels at BZS optimum concentration in 15% M HCl

TABLE 5 Corrosion Rate and Corrosion efficiency of N80 steels in 15% HCl, optimum concentration (300mg/L) with and without BZS, and use with different formulations at different temperatures

TABLE 6

Composition of different BZS-based corrosion inhibitor formulas

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.