阅读说明：本技术 一种喹啉类双季铵盐型酸洗缓蚀剂及其制备方法 (Quinoline bis-quaternary ammonium salt type pickling corrosion inhibitor and preparation method thereof ) 是由 郝俊生 秦涛 张永斌 于海英 于 2019-09-23 设计创作，主要内容包括：本发明公开了一种喹啉类双季铵盐型酸洗缓蚀剂及其制备方法。所述的喹啉类双季铵盐型酸洗缓蚀剂的制备方法是：以6-氨基喹啉为起始原料,与丙二酸二乙酯反应得到N,N’-二(6-喹啉基)丙二酰胺,再与溴代烷烃反应制得丙二酰胺桥联的喹啉类双季铵盐。本发明提供的喹啉类双季铵盐型酸洗缓蚀剂具有良好的缓蚀效果,在35℃、15%盐酸条件下,加入量为5×10<Sup>-5</Sup> mol/L,对N80钢片的缓蚀率可达97.07%,具有用量少、性能优的特点。本发明提供的喹啉类双季铵盐型酸洗缓蚀剂结构中含有酰胺、喹啉和季铵盐不同类型有机缓蚀剂的特征,使用时不需要复配,即可达到“1+1≥2”的协同效应。(The invention discloses a quinoline bis-quaternary ammonium salt pickling corrosion inhibitor and a preparation method thereof. The preparation method of the quinoline bis-quaternary ammonium salt pickling corrosion inhibitor comprises the following steps: 6-aminoquinoline is used as a starting material to react with diethyl malonate to obtain N, N '-di (6-quinolyl) malonamide, and then the N, N' -di (6-quinolyl) malonamide reacts with alkyl bromide to obtain the quinoline biquaternary ammonium salt bridged by the malonamide. The quinoline double quaternary ammonium salt pickling corrosion inhibitor provided by the invention has a good corrosion inhibition effect, and the addition amount is 5 multiplied by 10 under the conditions of 35 ℃ and 15% hydrochloric acid ‑5 The mol/L corrosion inhibition rate on the N80 steel sheet can reach 97.07%, and the steel sheet has the characteristics of less consumption and excellent performance. The quinoline double quaternary ammonium salt pickling corrosion inhibitor provided by the invention has the characteristics that the structure contains different types of organic corrosion inhibitors such as amide, quinoline and quaternary ammonium salt, and the quinoline double quaternary ammonium salt pickling corrosion inhibitor does not need to be compounded when in useThe synergistic effect of 1+1 ≥ 2' can be achieved.)

1. A quinoline bis-quaternary ammonium salt type pickling corrosion inhibitor is characterized in that the quinoline bis-quaternary ammonium salt is malonamide bridged and has the following structural formula:

wherein R represents a long-chain alkane having 8, 10, 12 or 14 carbon atoms.

2. A method for preparing quinoline diquaternary ammonium salt pickling corrosion inhibitor as claimed in claim 1, characterized in that 6-aminoquinoline is used as starting material, reacted with diethyl malonate to obtain N, N' -di (6-quinolyl) malonamide, and then reacted with alkyl bromide to obtain the quinoline diquaternary ammonium salt bridged with malonamide.

3. The method for preparing the quinoline bis-quaternary ammonium salt pickling corrosion inhibitor according to claim 2, comprising the following steps:

(1) preparing N, N '-bis (6-quinolyl) malonamide by adding diethyl malonate and 2 ~ 4 times of 6-aminoquinoline in molar amount into a reaction bottle, adding solvent N, N-dimethylformamide in an amount of 5 ~ 6 times that of diethyl malonate, heating to 130 ~ 140 ℃ for 7 ~ 10 hours, cooling, adding ethyl acetate in an amount of 3 ~ 5 times that of N, N-dimethylformamide, freezing at-18 ℃ of ~ -12 ℃ for 8 ~ 10 hours in a freezer, performing suction filtration, and washing with ethyl acetate to obtain N, N' -bis (6-quinolyl) malonamide;

(2) adding N, N' -di (6-quinolyl) malonamide and bromoalkane into a reaction bottle, adding N, N-dimethylformamide, heating to 105 ~ 115 ℃, reacting for 8 ~ 10 hours, cooling, performing suction filtration, and recrystallizing with acetone to obtain the malonamide bridged quinoline biquaternary ammonium salt.

4. The method for preparing quinoline bis-quaternary ammonium salt pickling corrosion inhibitor according to claim 3, wherein the ratio of the amount of N, N' -bis (6-quinolyl) malonamide, the amount of bromoalkane and the amount of N, N-dimethylformamide is 1 mmol: 8 ~ 12 mmol: 1.5 ~ 2.5.5 ml.

5. The method for preparing quinoline bis-quaternary ammonium salt pickling corrosion inhibitor according to claim 3, wherein the obtained corrosion inhibitor is used in an amount of 5 x 10 under the conditions of 35 ℃ and 15% hydrochloric acid in a corrosion inhibition effect test on N80 steel sheets^-5The mol/L corrosion inhibition rate on the N80 steel sheet reaches 97.07 percent.

Technical Field

The invention belongs to the technical field of corrosion inhibitors, and particularly relates to a quinoline bis-quaternary ammonium salt pickling corrosion inhibitor and a preparation method thereof.

Background

Acid washing is a common method for cleaning and descaling the surface of a metal material, and is widely applied to industries such as metal processing, metallurgy, chemical industry, electric power and the like. Meanwhile, acidification is also an effective measure for improving the recovery ratio in the process of exploiting the oil and gas field. However, the pickling or acidification process can cause certain corrosion to metal devices and equipment pipelines, and the corrosion inhibitor is an effective method for retarding corrosion. The corrosion inhibitors used at the earliest are inorganic salts such as chromate, nitrite and phosphate, and the inorganic corrosion inhibitors are gradually replaced by organic corrosion inhibitors due to high consumption, high investment cost and serious environmental damage. The organic corrosion inhibitor mainly comprises compounds containing nitrogen, oxygen, sulfur, phosphorus and other electronegative atoms, which can form chemical bonds with metals and adsorb on the metal surface to form a film so as to achieve the purpose of protecting the metals. Common organic corrosion inhibitors at present are: amides, mannich bases, imidazolines, quaternary ammonium salts, thioureas, quinolines, and other heterocyclic compounds, and the like. Under the general conditions, the organic corrosion inhibitor has the advantages of small dosage, good corrosion inhibition performance, wide application range and the like, and is favored by the industry. With the continuous improvement of the scientific and technological level and the awareness of environmental protection, the requirements of different industries on corrosion inhibitors are higher and higher, so the research on developing novel efficient and environment-friendly organic corrosion inhibitors and the compounding of the corrosion inhibitors is a research hotspot in the field.

Disclosure of Invention

The invention aims to provide a quinoline bis-quaternary ammonium salt type pickling corrosion inhibitor and a preparation method thereof, and the method is simple to prepare and is environment-friendly.

The quinoline double quaternary ammonium salt type pickling corrosion inhibitor provided by the invention has the characteristics of different types of organic corrosion inhibitors such as amide, quinoline and quaternary ammonium salt in the structure, and can achieve the synergistic effect of '1 +1 is more than or equal to 2' without compounding when in use.

The invention provides a quinoline bis-quaternary ammonium salt type pickling corrosion inhibitor, which is malonamide bridged quinoline bis-quaternary ammonium salt and has the following structural formula:

wherein R represents a long-chain alkane having 8, 10, 12 or 14 carbon atoms.

The invention provides a preparation method of the quinoline diquaternary ammonium salt pickling corrosion inhibitor, which takes 6-aminoquinoline as a starting material to react with diethyl malonate to obtain N, N' -di (6-quinolyl) malonamide, and then reacts with alkyl bromide to obtain the quinoline diquaternary ammonium salt bridged by the malonamide, wherein the reaction formula of the preparation process is as follows:

the preparation method comprises the following steps:

(1) preparing N, N '-bis (6-quinolyl) malonamide by adding diethyl malonate and 2 ~ 4 times of 6-aminoquinoline in molar amount into a reaction bottle, adding solvent N, N-dimethylformamide in an amount of 5 ~ 6 times that of diethyl malonate, heating to 130 ~ 140 ℃ for 7 ~ 10 hours, cooling, adding ethyl acetate in an amount of 3 ~ 5 times that of N, N-dimethylformamide, freezing at-18 ℃ of ~ -12 ℃ for 8 ~ 10 hours in a freezer, performing suction filtration, and washing with ethyl acetate to obtain N, N' -bis (6-quinolyl) malonamide;

(2) adding N, N' -di (6-quinolyl) malonamide and bromoalkane into a reaction bottle, adding N, N-dimethylformamide, heating to 105 ~ 115 ℃, reacting for 8 ~ 10 hours, cooling, performing suction filtration, and recrystallizing with acetone to obtain malonamide-bridged quinoline biquaternary ammonium salt;

wherein the dosage ratio of the N, N' -bis (6-quinolyl) malonamide, the bromoalkane and the N, N-dimethylformamide is 1 mmol: 8 ~ 12 mmol: 1.5 ~ 2.5.5 ml.

The corrosion inhibition effect evaluation of the quinoline double-quaternary ammonium salt pickling corrosion inhibitor provided by the invention is realized. With reference to SY/T5405-1996 performance test method and evaluation index of corrosion inhibitor for acidification, the corrosion rate and corrosion inhibition rate of the quinoline double quaternary ammonium salt pickling corrosion inhibitor provided by the invention on N80 steel sheets are evaluated by adopting an atmospheric static coupon weight loss method. The experimental results show that: the quinoline double quaternary ammonium salt pickling corrosion inhibitor has good corrosion inhibition effect, and is particularly implementedThe quinoline biquaternary ammonium salt prepared in example 1 has the best corrosion inhibition effect, and the addition amount is 5 multiplied by 10 under the conditions of 35 ℃ and 15% hydrochloric acid^-5The mol/L corrosion inhibition rate on the N80 steel sheet can reach 97.07%.

The invention has the beneficial effects that:

(1) the quinoline bis-quaternary ammonium salt pickling corrosion inhibitor provided by the invention has the advantages of easily available raw materials, simple preparation, easy degradation and environmental protection.

(2) The quinoline double quaternary ammonium salt type pickling corrosion inhibitor provided by the invention has the characteristics of different types of organic corrosion inhibitors such as amide, quinoline and quaternary ammonium salt in the structure, and can achieve the synergistic effect of '1 +1 is more than or equal to 2' without compounding when in use.

(3) The quinoline double-quaternary ammonium salt pickling corrosion inhibitor provided by the invention has the characteristics of small using amount and good corrosion inhibition performance.

Drawings

FIG. 1 is a nuclear magnetic hydrogen spectrum of N, N' -bis (1-N-octyl-6-quinolyl) malonamide bis-quaternary ammonium bromide.

FIG. 2 is a nuclear magnetic carbon spectrum of N, N' -bis (1-N-octyl-6-quinolyl) malonamide bis-quaternary ammonium bromide.

Detailed Description

The present invention is further illustrated by, but is not limited to, the following examples.