Mannich base quaternary ammonium salt compound and preparation method thereof, acidizing corrosion inhibitor, acid liquor and application thereof

Abstract

The invention relates to the field of oil and gas development, and discloses a Mannich base quaternary ammonium salt compound and a preparation method thereof, an acidizing corrosion inhibitor, acid liquor and application thereof. The compound has a structure as shown in a formula (1): # imgabs0 #, wherein R1 and R2 are respectively and independently selected from hydrogen, C1-C5 straight-chain alkyl and C3-C5 branched-chain alkyl; x is selected from one or more of F, Cl and Br. The corrosion inhibitor system is resistant to high temperature and has excellent corrosion inhibition performance, so that the corrosion resistance of oil and gas exploitation equipment can be improved, and the safety, stability and high efficiency of the oil and gas exploitation process can be improved.

Description

Technical Field

[0001] The invention belongs to the field of oil and gas development, and specifically relates to a Mannich base quaternary ammonium salt compound and a preparation method thereof, an acidification corrosion inhibitor, an acid solution and applications thereof. Background Art

[0002] In the process of oil exploration and development, as the exploitation continues to deepen, the mining environment becomes more and more complex, and the mining efficiency becomes lower and lower. Acidizing of oil and gas wells can significantly improve the oil and gas recovery rate. Oil well acidizing technology uses acid to dissolve the blockages in rocks and permeable channels or formation fractures, thereby expanding the oil flow channel, reducing oil flow resistance, improving the permeability of oil and gas layer rocks, and increasing oil production rate.

[0003] However, in the process of acidizing the channel with acid, the acid system will inevitably cause a certain degree of corrosion to the production equipment and metal pipes along the line, and with the increase of well depth and the increase of bottom hole temperature (some well temperatures are even as high as 190°C), the corrosion caused by the acid system to the metal will also increase exponentially. In order to solve the problem of corrosion protection of oil well casing equipment by acidizing fluid, adding acidizing corrosion inhibitor to the system is currently the most economical and effective method.

[0004] At present, organic corrosion inhibitors are commonly used in the acidification process on the market, mainly heteroatom compounds such as Mannich bases, amides, imidazolines, pyridine, and quinoline quaternary ammonium salts. However, there are few corrosion inhibitors on the market that can meet the requirements of high-temperature acidification. High temperatures greatly weaken the corrosion inhibition ability of conventional corrosion inhibitors for metal equipment. In addition, conventional corrosion inhibitors are very easy to decompose and lose their corrosion inhibition performance at high temperatures, and they have the disadvantages of unstable performance such as easy coking and stratification at high temperatures, which may cause formation damage.

[0005] CN109294549A discloses a high-temperature oilfield acidizing corrosion inhibitor and a preparation method. The high-temperature oilfield acidizing corrosion inhibitor comprises the following components by weight: 30-60 parts of Mannich base, 40-60 parts of propylene glycol, 5-10 parts of octadecyltrimethylammonium chloride, and 0.5-2 parts of antimony trioxide. The technical solution uses propargyl alcohol as the reaction raw material, but this substance is a flammable liquid and highly toxic. In view of safety considerations, this technical solution is not easy to be widely promoted.

[0006] CN109355663A discloses a corrosion inhibitor for oil fields, a preparation method of the corrosion inhibitor and its application. The corrosion inhibitor comprises 50-100 parts of oleic acid, 20-40 parts of diethylenetriamine, 80-120 parts of ethylene oxide, an appropriate amount of catalyst, 100-200 parts of dispersant and 600-700 parts of water. The technical solution uses a strong imidazoline quaternary ammonium salt as the main component, and adds alcohol, a high-efficiency penetrant, a surfactant, etc., so as to form a corrosion inhibitor with strong targeting to produced water. However, this corrosion inhibitor is not suitable for use in high temperature environments.

[0007] CN110079807A discloses an oilfield anti-scaling and corrosion inhibitor suitable for high temperature and its preparation method. However, the anti-scaling and corrosion inhibitor is only suitable for high temperature environment of 70°C to prevent corrosion caused by low acidity, high mineralization, CO2 and H2S and high temperature, but no guidance is given for the adaptability to temperature conditions above 160°C.

[0008] Therefore, developing a new type of corrosion inhibitor that is both resistant to high temperatures and has excellent corrosion inhibition properties is not only beneficial to improving the anti-corrosion performance of oil and gas production equipment, but also has great significance for improving the safe, stable and efficient operation of the oil and gas production process. Summary of the invention

[0009] The purpose of the present invention is to overcome the problem that the corrosion inhibitor in the prior art has poor corrosion inhibition performance at high temperatures, and to provide a Mannich base quaternary ammonium salt compound and a preparation method thereof, an acidified corrosion inhibitor, an acid solution and applications thereof.

[0010] In order to achieve the above object, the first aspect of the present invention provides a Mannich base quaternary ammonium salt compound, wherein the compound has a structure shown in formula (1):

[0011]

[0012] Wherein, R1 and R2 are each independently selected from hydrogen, C1-C5 straight chain alkyl, C3-C5 branched chain alkyl, C1-C5 alkoxy or hydroxy-substituted C1-C5 alkyl; X is selected from one or more of F, Cl and Br.

[0013] The second aspect of the present invention provides a method for preparing a Mannich base quaternary ammonium salt compound, which comprises the following steps:

[0014] 1) mixing formaldehyde, compound A, a solvent and concentrated hydrochloric acid and performing a first reaction to obtain a product;

[0015] 2) subjecting the product to a second reaction with compound B to obtain a Mannich base compound;

[0016] 3) subjecting the Mannich base compound to a third reaction with compound C and subjecting the reaction to reduced pressure distillation to obtain the Mannich base quaternary ammonium salt compound;

[0017] Wherein, compound A has the structure shown in formula (2): Compound B has the structure shown in formula (3): Compound C has the structure shown in formula (4): Wherein X is selected from F, Cl or Br; the definitions of R1 and R2 are the same as those in the first aspect.

[0018] The third aspect of the present invention provides an acidifying corrosion inhibitor, which comprises, based on the total amount of the acidifying corrosion inhibitor, 15-40wt% of a Mannich base quaternary ammonium salt compound, 15-40wt% of a dichlorobenzyl bisquinoline quaternary ammonium salt, 3-15wt% of potassium iodide, 5-30wt% of peregal, 5-20wt% of an acetylene alcohol compound, 2-15wt% of an antimony salt and 2-40wt% of a saturated alcohol compound.

[0019] The fourth aspect of the present invention provides an acid solution, comprising: a basic acid; and the aforementioned acidifying corrosion inhibitor.

[0020] A fifth aspect of the present invention provides the use of the aforementioned acid solution in high-temperature reservoir oil and gas production.

[0021] Through the above technical solution, the beneficial technical effects achieved by the present invention are as follows:

[0022] The present invention provides an acidizing corrosion inhibitor composed of specific components in specific amounts, which can be applied to the acidizing process of oil and gas channels in high-temperature reservoirs at 160-180°C. The corrosion inhibitor system of the present invention is both high-temperature resistant and has excellent corrosion inhibition performance, thereby improving the anti-corrosion performance of oil and gas production equipment and helping to improve the safety, stability and efficiency of the oil and gas production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a sample diagram of the Mannich base quaternary ammonium salt compound prepared in Preparation Example 1;

[0024] Figure 2 This is the NMR analysis of the Mannich base quaternary ammonium salt compound prepared in Preparation Example 1;

[0025] Figure 3 This is a sample diagram of the p-dichlorobenzyl bisquinoline quaternary ammonium salt prepared in Preparation Example 5;

[0026] Figure 4 This is the nuclear magnetic resonance spectrum of the p-dichlorobenzyl bisquinoline quaternary ammonium salt prepared in Preparation Example 5. DETAILED DESCRIPTION

[0027] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0028] The first aspect of the present invention provides a Mannich base quaternary ammonium salt compound, wherein the compound has a structure shown in formula (1):

[0029]

[0030] Wherein, R1 and R2 are each independently selected from hydrogen, C1-C5 straight chain alkyl, C3-C5 branched chain alkyl, C1-C5 alkoxy or hydroxy-substituted C1-C5 alkyl; X is selected from one or more of F, Cl and Br.

[0031] In some embodiments of the present invention, R1 and R2 are each independently selected from hydrogen, methyl, ethyl or isopropyl.

[0032] In some embodiments of the present invention, preferably, the compound can be selected from at least one of the following compounds:

[0033]

[0034] In the present invention, the composition and structure of the above compounds can be determined by NMR, IR, GPC, elemental analysis, etc., or by preparing and feeding.

[0035] The second aspect of the present invention provides a method for preparing a Mannich base quaternary ammonium salt compound, which comprises the following steps:

[0036] 1) mixing formaldehyde, compound A, a solvent and concentrated hydrochloric acid and performing a first reaction to obtain a product;

[0037] 2) subjecting the product to a second reaction with compound B to obtain a Mannich base compound;

[0038] 3) subjecting the Mannich base compound to a third reaction with compound C and subjecting the reaction to reduced pressure distillation to obtain the Mannich base quaternary ammonium salt compound;

[0039] Wherein, compound A has the structure shown in formula (2): Compound B has the structure shown in formula (3): Compound C has the structure shown in formula (4): Wherein X is selected from F, Cl or Br; the definitions of R1 and R2 are the same as those in the first aspect.

[0040] In some embodiments of the present invention, R1 and R2 are each independently selected from hydrogen, methyl, ethyl or isopropyl.

[0041] In some embodiments of the present invention, preferably, compound A is selected from At least one of;

[0042] Compound B is selected from At least one of (3-4);

[0043] Compound C is selected from At least one of (4-1).

[0044] In some embodiments of the present invention, the solvent is dimethylformamide and / or an alcohol solvent.

[0045] In some embodiments of the present invention, the first reaction temperature is 90-140° C., and the first reaction time is 1-5 h.

[0046] In some embodiments of the present invention, preferably, the first reaction temperature is 110-120° C., and the first reaction time is 2-3 h.

[0047] In some embodiments of the present invention, the second reaction temperature is 90-140° C., and the second reaction time is 3-8 h.

[0048] In some embodiments of the present invention, preferably, the second reaction temperature is 110-120° C., and the second reaction time is 4-6 h.

[0049] In some embodiments of the present invention, the third reaction temperature is 90-130° C., and the third reaction time is 5-10 h.

[0050] In some embodiments of the present invention, preferably, the third reaction temperature is 110-120° C., and the third reaction time is 6-8 h.

[0051] In some embodiments of the present invention, the pressure of the reduced pressure distillation is -0.05 MPa to -0.15 MPa, preferably -0.07 MPa to -0.1 MPa.

[0052] In some embodiments of the present invention, the molar ratio of formaldehyde, compound A and compound B is 1-2:1-2:0.8-2, preferably 1.2-1.5:1.2-1.5:1-1.5.

[0053] In some embodiments of the present invention, the molar ratio of the Mannich base compound to compound C is 0.8-2:0.2-1, preferably 1-1.5:0.4-0.8.

[0054] The third aspect of the present invention provides an acidifying corrosion inhibitor, which comprises, based on the total amount of the acidifying corrosion inhibitor, 15-40wt% of a Mannich base quaternary ammonium salt compound, 15-40wt% of a dichlorobenzyl bisquinoline quaternary ammonium salt, 3-15wt% of potassium iodide, 5-30wt% of peregal, 5-20wt% of an acetylene alcohol compound, 2-15wt% of an antimony salt and 2-40wt% of a saturated alcohol compound.

[0055] In the present invention, Mannich base quaternary ammonium salt and p-dichlorobenzyl bisquinoline quaternary ammonium salt are both main components, so that the corrosion inhibitor can be adsorbed on the metal surface to form a protective film; the molecular volume of acetylene alcohol compounds is relatively small, and adsorption and protection can be formed in the molecular gap of the main protective film, which is a beneficial supplement to the main agent; potassium iodide and various components work together to promote adsorption and protection; antimony salts can promote adsorption and film formation; perchlorate is a surfactant to promote uniform dispersion and adsorption of other components, and saturated alcohol compounds play a dissolving and dispersing role. The various components of the present invention work together, and the acidified corrosion inhibitor obtained within the above-mentioned component range is both resistant to high temperature and has excellent corrosion inhibition performance, thereby improving the anticorrosion performance of oil and gas production equipment, and can be applied to the acidification process of oil and gas channels in high-temperature reservoirs of 160-180°C.

[0056] The acidizing corrosion inhibitor of the present invention is composed of specific components in specific amounts and can be applied to the acidizing process of oil and gas channels in high-temperature reservoirs at 160-180°C.

[0057] In some embodiments of the present invention, the content of the Mannich base quaternary ammonium salt can be selected from 15wt%, 20wt%, 25wt%, 30wt%, 35wt%, 40wt%, and any value in the range consisting of any two of the above values.

[0058] In some embodiments of the present invention, the mass percentage of the p-dichlorobenzyl-bisquinoline-type quaternary ammonium salt can be selected from 15wt%, 20wt%, 25wt%, 30wt%, 35wt%, 40wt%, and any value in the range consisting of any two of the above values.

[0059] In some embodiments of the present invention, the mass percentage of the potassium iodide can be selected from 3wt%, 5wt%, 10wt%, 15wt%, and any value in the range consisting of any two of the above values.

[0060] In some embodiments of the present invention, the mass percentage of the pingpingjia can be selected from 5wt%, 10wt%, 15wt%, 20wt%, 25wt%, 30wt%, and any value in the range consisting of any two of the above values.

[0061] In some embodiments of the present invention, the mass percentage of the acetylene alcohol compound can be selected from 5wt%, 10wt%, 15wt%, 20wt%, and any value in the range consisting of any two of the above values.

[0062] In some embodiments of the present invention, the mass percentage of the antimony salt can be selected from 2wt%, 5wt%, 10wt%, 15wt%, and any value in the range consisting of any two of the above values.

[0063] In some embodiments of the present invention, the mass percentage of the saturated alcohol compound can be selected from 2wt%, 10wt%, 15wt%, 25wt%, 30wt%, 35wt%, 40wt%, and any value in the range consisting of any two of the above values.

[0064] In some embodiments of the present invention, the acidifying corrosion inhibitor includes the following components in mass percentage: 20-30wt% of Mannich base quaternary ammonium salt, 20-30wt% of dichlorobenzyl bisquinoline quaternary ammonium salt, 5-10wt% of potassium iodide, 10-20wt% of peregal, 10-15wt% of acetylene alcohol compounds, 5-10wt% of antimony salts and 5-35wt% of saturated alcohol compounds.

[0065] In some embodiments of the present invention, the antimony salt is selected from antimony chloride and antimony carbonate.

[0066] In some embodiments of the present invention, the alkynol compound is selected from methyl pentynol and / or propynol; preferably methyl pentynol.

[0067] In some embodiments of the present invention, the saturated alcohol compound is selected from isopropanol and / or ethanol, preferably isopropanol.

[0068] In some embodiments of the present invention, the peregrin is a fatty alcohol polyoxyethylene ether having the structural formula RO(CH2CH2O) n H, R = C 16 -C 18 , n=9-30.

[0069] In some embodiments of the present invention, the p-dichlorobenzyl-bisquinoline-type quaternary ammonium salt has a structure shown in formula (4):

[0070]

[0071] In some embodiments of the present invention, the p-dichlorobenzyl-type bisquinoline-type quaternary ammonium salt is prepared using quinoline and 1,4-p-dichlorobenzyl as reaction raw materials.

[0072] In some embodiments of the present invention, the method for preparing the p-dichlorobenzyl-type bisquinoline-type quaternary ammonium salt comprises the following steps:

[0073] 1) mixing quinoline, 1,4-dichlorobenzyl and water, heating the mixture and performing a reflux reaction;

[0074] 2) The system after the reaction is heated and concentrated, cooled and crystallized to obtain a crude product, and then the crude product is recrystallized, filtered and dried to obtain a p-dichlorobenzyl-type bisquinoline-type quaternary ammonium salt.

[0075] In some embodiments of the present invention, the reflux reaction temperature is 80-120° C., and the reflux reaction time is 4-10 h.

[0076] In some embodiments of the present invention, preferably, the reflux reaction temperature is 90-110° C., and the reflux reaction time is 5-8 h.

[0077] In some embodiments of the present invention, the molar ratio of quinoline to 1,4-dichlorobenzyl is 1-4:1, preferably 2-3:1.

[0078] In some embodiments of the present invention, the base acid is hydrochloric acid.

[0079] According to a particularly preferred embodiment of the present invention, an acidifying corrosion inhibitor comprises the following components in mass percentage: 20-30wt% of Mannich base quaternary ammonium salt, 20-30wt% of p-dichlorobenzyl bisquinoline quaternary ammonium salt, 5-10wt% of potassium iodide, 10-20wt% of peregal, 10-15wt% of alkynol compound, 5-10wt% of antimony salt and 5-35wt% of saturated alcohol compound;

[0080] Wherein, the structural formula of the Mannich base quaternary ammonium salt compound is (1-1), the preparation method thereof comprises the following steps:

[0081] 1) Mixing formaldehyde, 2-(methylamino)pyridine, anhydrous ethanol and concentrated hydrochloric acid, and performing a first reaction at 110-120° C. for 2-3 hours to obtain a product;

[0082] 2) subjecting the product to a second reaction with 2-acetylpyridine at 110-120° C. for 4-6 hours to obtain a Mannich base;

[0083] 3) performing a third reaction of the Mannich base with 1,4-dichlorobenzyl at 110-120° C. for 6-8 hours, and performing reduced pressure distillation at -0.07 MPa to -0.1 MPa to obtain the Mannich base quaternary ammonium salt;

[0084] The molar ratio of formaldehyde, 2-(methylamino)pyridine and 2-acetylpyridine is 1.2-1.5:1.2-1.5:1-1.5, and the molar ratio of Mannich base and 1,4-dichlorobenzyl is 1-1.5:0.4-0.8;

[0085] The p-dichlorobenzyl bisquinoline quaternary ammonium salt structural formula is (4), the preparation method thereof comprises the following steps:

[0086] 1) Mix quinoline, 1,4-dichlorobenzyl and water, raise the temperature, and reflux for 5-8 hours at 90-110° C.;

[0087] 2) heating and concentrating the system after the reaction, cooling and crystallizing to obtain a crude product, and then recrystallizing, filtering and drying the crude product to obtain a p-dichlorobenzyl-type bisquinoline-type quaternary ammonium salt;

[0088] Wherein, the molar ratio of quinoline to 1,4-dichlorobenzyl is 1-3:1.

[0089] A fourth aspect of the present invention provides an acid solution, comprising: a basic acid and the aforementioned acidifying corrosion inhibitor.

[0090] In some preferred embodiments, based on the total amount of the acid solution, the content of the acidizing corrosion inhibitor in the acid solution is 2-8wt%, preferably 2-4wt%, and more preferably 4wt%; and the content of the base acid is 15-28wt%.

[0091] In some preferred embodiments, the amount of the acidifying corrosion inhibitor is 2-8wt% of the total weight of the acid solution, for example 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, and any value in the range composed of any two of the above values, preferably 2-4wt%, more preferably 4wt%.

[0092] In some preferred embodiments, the amount of the base acid is 15-28wt% of the total weight of the acid solution, for example 15wt%, 18wt%, 20wt%, 22wt%, 25wt%, 28wt%, and any value in the range consisting of any two of the above values.

[0093] A fifth aspect of the present invention provides the use of the aforementioned acid solution in high-temperature reservoir oil and gas production.

[0094] The present invention provides an acidizing corrosion inhibitor composed of specific components in specific amounts, which can be applied to the acidizing process of oil and gas channels in high-temperature reservoirs at 160-180°C. The corrosion inhibitor system of the present invention is both high-temperature resistant and has excellent corrosion inhibition performance, thereby improving the anti-corrosion performance of oil and gas production equipment and helping to improve the safety, stability and efficiency of the oil and gas production process.

[0095] The present invention will be described in detail below through examples.

[0096] In the following examples and comparative examples, if no specific conditions are specified, the experiments are carried out under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used, if no manufacturer is specified, are conventional products that can be obtained through commercial channels. The composition and structure of the compounds described in the following examples and comparative examples can be determined by nuclear magnetic resonance, infrared, GPC, elemental analysis, etc., or by preparing and feeding.

[0097] Preparation Example 1 Preparation of Mannich Base Quaternary Ammonium Salt Compound

[0098] 20mL of anhydrous ethanol, 0.5mL of concentrated hydrochloric acid, 2mL of formaldehyde solution and 2.59g of 2-(methylamino)pyridine were added to a 50mL round-bottom flask, and the first reaction was carried out at 110°C for 2h, and then 2.42g of 2-acetylpyridine was added to carry out the second reaction for 4h to obtain a Mannich base compound; 1.40g of 1,4-dichlorobenzyl was added, and the third reaction was continued at 110°C for 6h, and finally a deep red Mannich base quaternary ammonium salt compound was obtained by reduced pressure distillation at -0.07MPa using a rotary evaporator. The molar ratio of the materials during the reaction is approximately: n[formaldehyde]:n[2-(methylamino)pyridine]:n[2-acetylpyridine]=1.2:1.2:1; n[Mannich base compound]:n[1,4-dichlorobenzyl]=1:0.4. The example synthesis equation of Mannich base quaternary ammonium salt compound is as follows:

[0099]

[0100] The synthesized Mannich base quaternary ammonium salt samples are as follows Figure 1 shown.

[0101] Using heavy water as solvent, the NMR analysis of Mannich base quaternary ammonium salt is as follows Figure 2 As shown. In the spectrum, the multiple peak of δ2.86 is attributed to the three hydrogen atoms on the methyl group at position 1, the multiple peaks at δ3.06 and δ3.39 are attributed to the two hydrogen atoms of the methylene group at positions 2 and 3, respectively, the multiple peak at δ4.32 is attributed to the two hydrogen atoms of the methylene group at position 4, and the multiple peaks at δ6.73-7.95 are attributed to the hydrogen atoms on the pyridine ring and benzene ring at positions 5, 6, 7 and 8. The nuclear magnetic resonance spectrum shows that the synthesized Mannich base quaternary ammonium salt is the target product, and its structural formula is

[0102] Preparation Example 2

[0103] A Mannich base quaternary ammonium salt compound was prepared according to the method of Preparation Example 1. The molar ratio of materials during the reaction was approximately: n[formaldehyde]:n[2-(methylamino)-4-methylpyridine]:n[2-acetylpyridine]=2:2:0.8; n[Mannich base compound]:n[1,4-dichlorobenzyl]=1.2:0.8.

[0104] Wherein, the compound A is 2-(methylamino)-4-methylpyridine, the compound B is 2-acetylpyridine, and the structural formula of the obtained Mannich base quaternary ammonium salt compound is

[0105] Preparation Example 3

[0106] A Mannich base quaternary ammonium salt compound was prepared according to the method of Preparation Example 1. The molar ratio of materials during the reaction was approximately: n[formaldehyde]:n[2-(methylamino)-4-methylpyridine]:n[2-acetyl-5-isopropylpyridine]=1.5:1.5:1.5; n[Mannich base compound]:n[1,4-dichlorobenzyl]=1:1.

[0107] Wherein, the compound A is 2-(methylamino)-4-methylpyridine, the compound B is 2-acetyl-5-isopropylpyridine, and the structural formula of the obtained Mannich base quaternary ammonium salt compound is

[0108]

[0109] Preparation Example 4

[0110] A Mannich base quaternary ammonium salt compound was prepared according to the method of Preparation Example 1. The molar ratio of materials during the reaction was approximately: n[formaldehyde]:n[2-(methylamino)-4-ethylpyridine]:n[2-acetyl-5-isopropylpyridine]=1:1:2; n[Mannich base compound]:n[1,4-dichlorobenzyl]=2:0.1.

[0111] Wherein, the compound A is 2-(methylamino)-4-ethylpyridine, the compound B is 2-acetyl-5-isopropylpyridine, and the structural formula of the obtained Mannich base quaternary ammonium salt compound is

[0112]

[0113] The Mannich base quaternary ammonium salt compound was prepared according to the method of Preparation Example 1. The material molar ratio and reaction conditions used in each Preparation Example 2-4 are shown in Table 1.

[0114] Table 1

[0115] project Preparation Example 2 Preparation Example 3 Preparation Example 4 First reaction temperature / ℃ 120 90 140 First reaction time / h 3 5 1 Second reaction temperature / ℃ 120 90 140 Second reaction time / h 6 8 3 The third reaction temperature / ℃ 120 90 130 The third reaction time / h 8 10 5 n[Formaldehyde]:n[Compound A]:n[Compound B] 2:2:0.8 1.5:1.5:1.5 1:1:2 n[Mannich base compounds]:n[1,4-dichlorobenzyl] 1.2:0.8 1:1 2:0.2

[0116] Preparation Example 5 Preparation of dichlorobenzyl-type bisquinoline-type quaternary ammonium salt

[0117] Add 50mL of distilled water to a 100mL three-necked flask, weigh 7.9863g of quinoline and 5.4206g of 1,4-dichlorobenzyl and add them to the three-necked flask (the system is layered, the upper layer is a yellow transparent oily substance, and the lower layer is a transparent water layer), connect a reflux condenser, a thermometer, etc., and heat on an electric heating mantle (the transparent water layer gradually turns yellow). After the temperature reaches 100°C, reflux for 6h (the system changes from brownish red to orange, and there are a few oil droplets on the surface of the system), stop heating, cool and pour into a crucible, heat and concentrate, cool and crystallize to obtain a yellow crude product, then recrystallize with anhydrous ethanol, filter, and dry to obtain an earthy final product (5.4962g). The material molar ratio during the reaction is approximately: n[quinoline]:n[1,4-dichlorobenzyl]=2:1. The synthesis equation of the dichlorobenzyl type bisquinoline type quaternary ammonium salt is as follows:

[0118] The prepared quaternary ammonium salt samples of p-dichlorobenzylbisquinoline are as follows: Figure 3 shown.

[0119] Using heavy water as solvent, the NMR spectrum of dichlorobenzyl bisquinoline quaternary ammonium salt is as follows Figure 4 As shown. In the spectrum, the multiple peaks of δ7.14-7.31 are attributed to the 4 hydrogen atoms on the 9th benzene ring, the peak of δ6.1 is attributed to the 4 hydrogen atoms on the methylene connected to the 10th benzene ring, and the multiple peaks of δ7.60-9.24 are attributed to the 14 hydrogen atoms on the 11th quinoline ring. The nuclear magnetic resonance spectrum shows that the synthesized p-dichlorobenzyl bisquinoline quaternary ammonium salt is the target product, and its structural formula is

[0120]

[0121] Preparation Example 6-8

[0122] The p-dichlorobenzyl-bisquinoline-type quaternary ammonium salt was prepared according to the method of Preparation Example 5. The material molar ratios and reaction conditions used in Preparation Examples 6-8 are shown in Table 2.

[0123] Table 2

[0124] project Preparation Example 6 Preparation Example 7 Preparation Example 8 Reflux reaction temperature / ℃ 90 110 120 Reflux reaction time / h 6 8 10 n[Quinoline]:n[1,4-dichlorobenzyl] 2:1 3:1 4:1

[0125] Examples 1-7

[0126] The acidifying corrosion inhibitors of Examples 1-7 were prepared according to the formula in Table 3.

[0127] The prepared acidifying corrosion inhibitor was added into the hydrochloric acid solution according to the proportion in Table 3 to obtain an acid solution product.

[0128] Table 3

[0129]

[0130] Table 3 (continued)

[0131]

[0132] Comparative Examples 1-3

[0133] The acidifying corrosion inhibitors of Comparative Examples 1-3 were prepared according to the formula in Table 4.

[0134] The prepared acidifying corrosion inhibitor was added into the hydrochloric acid solution according to the proportion in Table 4 to obtain an acid solution product.

[0135] Table 4

[0136]

[0137] Performance Evaluation

[0138] According to SY / T5405-2019 "Performance Test Method and Evaluation Index of Corrosion Inhibitors for Acidification", the corrosion inhibition performance of the acidification corrosion inhibitors of each embodiment was evaluated, and the high temperature and high pressure dynamic corrosion rate was tested in the acid-rock reaction rotating rock disc instrument. The test piece material is N80 standard steel sheet, which is cleaned in acetone to remove oil stains, the size of the steel sheet is measured, and it is taken out and air-dried after being soaked in anhydrous ethanol, and then placed in a dryer for weighing. The weighed steel sheet is placed in the acid solution, reacted at the target temperature for 4 hours, and then the steel sheet is cleaned with water, acetone, and ethanol in turn, and then the steel sheet is dried and weighed, and the corrosion rate is calculated. The test results of each embodiment and comparative example are shown in Table 5.

[0139] Table 5

[0140] serial number Temperature / ℃ <![CDATA[Corrosion rate / g / (m 2 ·h)]]> Example 1 180 68.85 Example 2 160 35.75 Example 3 160 41.26 Example 4 160 46.32 Example 5 160 55.12 Example 6 160 62.70 Example 7 160 72.14 Comparative Example 1 160 167.48 Comparative Example 2 160 189.38 Comparative Example 3 160 322.89

[0141] Taking Example 3 as an example, the results of the corrosion inhibition test at 180°C are shown in Table 6.

[0142] Table 6

[0143]

[0144] It can be seen from the results in Table 1 that the embodiments of the present invention meet the requirements of the industry standard SY / T5405-2019 "Performance Test Method and Evaluation Index of Corrosion Inhibitors for Acidification" and have significantly better effects.

[0145] It can be seen from the results of Table 5 that compared with Examples 1-7, the corrosion rate of the acidifying corrosion inhibitor obtained in Comparative Example 1 without adding p-dichlorobenzyl-bisquinoline-type quaternary ammonium salt increases sharply, and the corrosion inhibition performance is poor. The corrosion rate of the acidifying corrosion inhibitor obtained in Comparative Example 2 without adding Mannich base quaternary ammonium salt compound increases sharply, and the corrosion inhibition performance is poor. Comparative Example 3 is an acidifying corrosion inhibitor obtained outside the content range of the present invention, and the corrosion inhibition performance is poor. Among them, Example 7 is an acidifying corrosion inhibitor obtained without adding potassium iodide, and the corrosion inhibition performance is slightly worse than that of other embodiments. Therefore, the various components of the present invention work synergistically, and the acidifying corrosion inhibitor obtained within the above-mentioned component range is both resistant to high temperature and has excellent corrosion inhibition performance, thereby improving the corrosion resistance of oil and gas production equipment, and can be applied to the acidification process of oil and gas channels in high-temperature reservoirs of 160-180°C.

[0146] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A Mannich base quaternary ammonium salt compound, characterized in that The compound has a structure shown in formula (1): Wherein, R1 and R2 are each independently selected from hydrogen, C1-C5 straight chain alkyl, C3-C5 branched chain alkyl, C1-C5 alkoxy or hydroxy-substituted C1-C5 alkyl; X is selected from one or more of F, Cl and Br.

2. The compound according to claim 1, characterized in that R1 and R2 are each independently selected from hydrogen, methyl, ethyl or isopropyl.

3. The compound according to claim 1, characterized in that The compound is selected from at least one of the following compounds:

4. A method for preparing a Mannich base quaternary ammonium salt compound, characterized in that: The steps include: 1) mixing formaldehyde, compound A, a solvent and concentrated hydrochloric acid and performing a first reaction to obtain a product; 2) subjecting the product to a second reaction with compound B to obtain a Mannich base compound; 3) subjecting the Mannich base compound to a third reaction with compound C and subjecting the reaction to reduced pressure distillation to obtain the Mannich base quaternary ammonium salt compound; Wherein, compound A has the structure shown in formula (2): Compound B has the structure shown in formula (3): Compound C has the structure shown in formula (4): Wherein X is selected from F, Cl or Br; the definitions of R1 and R2 are the same as those in any one of claims 1 to 3.

5. The preparation method according to claim 4, characterized in that: R1, R2 are each independently selected from hydrogen, methyl, ethyl or isopropyl; Preferably, compound A is selected from At least one of; Compound B is selected from At least one of; Compound C is selected from At least one of;.

6. The preparation method according to claim 4 or 5, characterized in that: The solvent is dimethylformamide and / or an alcohol solvent; Preferably, the first reaction temperature is 90-140°C, preferably 110-120°C; the first reaction time is 1-5h, preferably 2-3h; Preferably, the second reaction temperature is 90-140°C, preferably 110-120°C; the second reaction time is 3-8h, preferably 4-6h; Preferably, the third reaction temperature is 90-130° C., preferably 110-120° C.; the third reaction time is 5-10 h, preferably 6-8 h; Preferably, the pressure of the reduced pressure distillation is -0.15 MPa to -0.05 MPa, preferably -0.1 MPa to -0.07 MPa; Preferably, the molar ratio of formaldehyde, compound A and compound B is 1-2:1-2:0.8-2, preferably 1.2-1.5:1.2-1.5:1-1.5; Preferably, the molar ratio of the Mannich base compound to compound C is 0.8-2:0.2-1, preferably 1-1.5:0.4-0.

8.

7. An acidification corrosion inhibitor, characterized in that: Based on the total amount of the acidifying corrosion inhibitor, the acidifying corrosion inhibitor includes: 15-40wt% of Mannich base quaternary ammonium salt compound, 15-40wt% of dichlorobenzyl type bisquinoline type quaternary ammonium salt, 3-15wt% of potassium iodide, 5-30wt% of peregal, 5-20wt% of acetylene alcohol compound, 2-15wt% of antimony salt and 2-40wt% of saturated alcohol compound.

8. The acidifying corrosion inhibitor according to claim 7, characterized in that: The acidizing corrosion inhibitor comprises the following components in mass percentage: 20-30wt% of Mannich base quaternary ammonium salt, 20-30wt% of p-dichlorobenzyl bisquinoline quaternary ammonium salt, 5-10wt% of potassium iodide, 10-20wt% of peregal, 10-15wt% of acetylene alcohol compounds, 5-10wt% of antimony salts and 5-35wt% of saturated alcohol compounds.

9. The acidifying corrosion inhibitor according to claim 7 or 8, characterized in that: The antimony salt is selected from antimony chloride and antimony carbonate; Preferably, the alkynol compound is selected from methylpentynol and / or propynol; Preferably, the saturated alcohol compound is selected from isopropanol and / or ethanol.

10. An acid solution, characterized in that: include: A base acid and the acidifying corrosion inhibitor according to any one of claims 7 to 9.

11. The acid solution according to claim 10, wherein The base acid is hydrochloric acid; And / or, based on the total amount of the acid solution, the content of the acidizing corrosion inhibitor in the acid solution is 2-8wt%, preferably 2-4wt%, more preferably 4wt%; and the content of the base acid is 15-28wt%.

12. Use of the acid solution according to claim 10 or 11 in high-temperature reservoir oil and gas production.

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