阅读说明：本技术 一种酯基聚醚甜菜碱表面活性剂及其合成方法 (Ester-based polyether betaine surfactant and synthesis method thereof ) 是由 陈晓刚 杜斌 任建军 王建军 吕营波 王曰鹏 于 2020-05-09 设计创作，主要内容包括：本发明公开了一种酯基聚醚甜菜碱表面活性剂及其合成方法,酯基聚醚甜菜碱结构通式为：RCO(OCH<Sub>2</Sub>CH<Sub>2</Sub>)<Sub>x</Sub>N<Sup>+</Sup>(CH<Sub>3</Sub>)<Sub>2</Sub>CH<Sub>2</Sub>COO<Sup>-</Sup>,其中R为脂肪酸基,X＝2～10。R具体为辛酸、癸酸、月桂酸、肉豆蔻酸、棕榈树、硬脂酸、油酸、芥酸中的一种或几种混合物。酯基聚醚甜菜碱同时具有烷基、酯基、醚基、甜菜碱四个基团,与原油具有较强的相似相溶性,对胶质、沥青质含量高的稠油具有较明显的乳化能力和渗透力,能够很好的将原油乳化在水中。经实践,对胜利油田东辛采油厂永8区块原油具有较好的乳化性,降粘率达到95％以上。与非离子烷醇聚醚相比,在产品的表面活性、水溶性及产品的耐盐、耐矿化度方面有明显优势。(The invention discloses an ester-based polyether betaine surfactant and a synthesis method thereof, wherein the general structural formula of the ester-based polyether betaine is as follows: RCO (OCH) 2 CH 2 ) x N + (CH 3 ) 2 CH 2 COO ‑ Wherein R is a fatty acid group, and X is 2-10. R is one or more of caprylic acid, capric acid, lauric acid, myristic acid, palm, stearic acid, oleic acid and erucic acid. The ester-based polyether betaine has four groups of alkyl, ester, ether and betaine, has strong similarity and intermiscibility with crude oil, and is colloid-resistantAnd the thick oil with high asphaltene content has obvious emulsifying capacity and permeability, and can well emulsify the crude oil in water. The practice proves that the crude oil has better emulsibility to the crude oil in the Yong 8 block of the Dongxin oil extraction plant of the Shengli oil field, and the viscosity reduction rate reaches more than 95 percent. Compared with nonionic alkanol polyether, the product has obvious advantages in the aspects of surface activity, water solubility, salt tolerance and mineralization resistance of the product.)

1. An ester-based polyether betaine surfactant is characterized in that the structural general formula of the ester-based polyether betaine is as follows: RCO (OCH)₂CH₂)_xN⁺(CH₃)₂CH₂COO^-Wherein R is a fatty acid group, and X is 2-10.

2. The ester based polyether betaine surfactant of claim 1, wherein R is one or a mixture of caprylic acid, capric acid, lauric acid, myristic acid, palm tree, stearic acid, oleic acid, and erucic acid.

3. The method of synthesizing an ester based polyether betaine surfactant of claim 1 or 2, comprising the steps of:

1) adding dimethylamine into a pressure reaction kettle, adding a proper amount of alkali catalyst, stirring, heating to 120-150 ℃, slowly introducing ethylene oxide, and keeping the temperature for 3-5 hours after the ethylene oxide is introduced to obtain dimethylamine polyoxyethylene ether;

2) putting fatty acid and dimethylamine polyoxyethylene ether into a reaction kettle, adding a proper amount of catalyst, heating to 120-180 ℃, and carrying out negative pressure reaction for 6-8 hours to obtain dimethyl polyoxyethylene ether fatty acid ester;

3) and (2) adding the dimethyl polyoxyethylene ether fatty acid ester, chloroacetate and a solvent into a reaction kettle, heating to 75-105 ℃, and reacting for 6-8 hours to obtain the fatty acid ester polyether betaine.

4. The method for synthesizing an ester based polyether betaine surfactant of claim 3, wherein the molar ratio of dimethylamine to ethylene oxide in step 1) is 1: 2-10.

5. The method for synthesizing an ester based polyether betaine surfactant as claimed in claim 3, wherein the alkali catalyst in step 1) is one or a mixture of sodium hydroxide, potassium hydroxide and monomethylamine, and the addition amount of the alkali catalyst is 0.5-2% of the total mass of all materials.

6. The method for synthesizing an ester based polyether betaine surfactant according to claim 3, wherein the fatty acid in the step 2) is one or a mixture of several of caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid and erucic acid, and the molar ratio of the fatty acid to the dimethylamine polyoxyethylene ether is 1: 1-2.

7. The method for synthesizing the ester based polyether betaine surfactant according to claim 3, wherein the catalyst in the step 2) is any one or a mixture of p-toluenesulfonic acid, zinc oxide, stannous oxalate and dilute sulfuric acid, and the addition amount of the catalyst is 0.1-2% of the total mass of all materials.

8. The method for synthesizing the ester-based polyether betaine surfactant according to claim 3, wherein the molar ratio of the dimethyl polyoxyethylene ether fatty acid ester to the chloroacetate in the step 3) is 1: 1-1.5, and the addition amount of the solvent is 20-80% of the total mass of all the materials.

9. The method for synthesizing an ester based polyether betaine surfactant according to claim 3 or 8, wherein the chloroacetate in step 3) is sodium chloroacetate or potassium chloroacetate, and the solvent is one or more of water, ethanol, methanol, isopropanol and propylene glycol.

Technical Field

The invention belongs to the field of surfactants, and particularly relates to an ester-based polyether betaine surfactant and a synthesis method thereof.

Background

The betaine surfactant serving as a novel, efficient and green amphoteric surfactant has the characteristics of low Critical Micelle Concentration (CMC), excellent calcium soap dispersibility, good foam stability, low toxicity and the like, and is widely applied to the fields of daily-use chemical industry, biochemical industry, textile industry, surface treatment industry and the like. In addition, the betaine surfactant has the characteristics of low cost of raw materials, good degradability, small environmental pollution and the like, and increasingly shows huge market potential.

Compared with other betaine surfactants, the ester-based polyether betaine has four groups of alkyl, ester, ether and betaine, wherein the alkyl group and the ester group are hydrophobic groups, and has stronger similarity and compatibility with crude oil; the ether group and the betaine group are hydrophilic groups, have obvious emulsifying capacity and permeability, and can well emulsify the crude oil in water.

Compared with alkyl betaine, the ester-based polyether betaine has stronger emulsifying and thickening capabilities; the emulsifier has two hydrophilic groups of ether group and betaine, so that emulsification and infiltration can be better performed in the aspect of crude oil infiltration and emulsification; compared with nonionic alkanol polyether, the product has obvious advantages in the aspects of surface activity, water solubility, salt tolerance and mineralization resistance of the product; compared with anions, the product has obvious advantages in the aspects of emulsifying capacity and hard water resistance, and is very stable under the conditions of different pH values.

Disclosure of Invention

The invention aims to provide an ester-based polyether betaine surfactant and a synthesis method thereof.

The invention solves the problems thatThe technical scheme adopted by the technical problem is as follows: an ester-based polyether betaine surfactant, wherein the structural general formula of the ester-based polyether betaine is as follows: RCO (OCH)₂CH₂)_xN⁺(CH₃)₂CH₂COO^-Wherein R is a fatty acid group, and X is 2-10. R is one or more of caprylic acid, capric acid, lauric acid, myristic acid, palm, stearic acid, oleic acid and erucic acid.

The synthesis method of the ester-based polyether betaine surfactant comprises the following steps:

1) adding dimethylamine into a pressure reaction kettle, adding a proper amount of alkali catalyst, stirring, heating to 120-150 ℃, slowly introducing ethylene oxide, and keeping the temperature for 3-5 hours after the ethylene oxide is introduced to obtain dimethylamine polyoxyethylene ether;

2) putting fatty acid and dimethylamine polyoxyethylene ether into a reaction kettle, adding a proper amount of catalyst, heating to 120-180 ℃, and carrying out negative pressure reaction for 6-8 hours to obtain dimethyl polyoxyethylene ether fatty acid ester;

3) and (2) adding the dimethyl polyoxyethylene ether fatty acid ester, chloroacetate and a solvent into a reaction kettle, heating to 75-105 ℃, and reacting for 6-8 hours to obtain the fatty acid ester polyether betaine.

Further, the molar ratio of dimethylamine to ethylene oxide in the step 1) is 1:2 to 10.

Further, the alkali catalyst in the step 1) is one or a mixture of several of sodium hydroxide, potassium hydroxide and monomethylamine, and the addition amount of the alkali catalyst is 0.5-2% of the total mass of all materials.

Further, in the step 2), the fatty acid is one or a mixture of several of caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid and erucic acid, and the molar ratio of the fatty acid to the dimethylamine polyoxyethylene ether is 1: 1-2.

Further, the catalyst in the step 2) is any one or a mixture of several of p-toluenesulfonic acid, zinc oxide, stannous oxalate and dilute sulfuric acid, and the adding amount of the catalyst is 0.1-2% of the total mass of all materials.

Further, the molar ratio of the dimethyl polyoxyethylene ether fatty acid ester to the chloroacetate in the step 3) is 1: 1-1.5, and the addition amount of the solvent is 20-80% of the total mass of all the materials.

Further, in the step 3), the chloroacetate is sodium chloroacetate or potassium chloroacetate, and the solvent is one or a mixture of water, ethanol, methanol, isopropanol and propylene glycol.

The invention has the following beneficial effects:

(1) the ester-based polyether betaine has four groups of alkyl, ester, ether and betaine, has strong similarity and intermiscibility with crude oil, has obvious emulsifying capacity and permeability to thick oil with high content of colloid and asphaltene, and can well emulsify the crude oil in water. The practice proves that the crude oil has better emulsibility to the crude oil in the Yong 8 block of the Dongxin oil extraction plant of the Shengli oil field, and the viscosity reduction rate reaches more than 95 percent.

(2) Compared with nonionic alkanol polyether, the product has obvious advantages in the aspects of surface activity, water solubility, salt tolerance and mineralization resistance of the product. The ester-based polyether betaine can reduce the interfacial tension value to 10 under the oil-water condition of the block, wherein the oil reservoir temperature reaches 80 ℃, the formation water mineralization degree is 40671mg/L, and the Yong8 block of the Dongxin oil extraction plant of the Shengli oil field has high temperature and high salinity^{- 3}mN/m。

(3) Compared with anions, the product has obvious advantages in the aspects of emulsifying capacity and hard water resistance, and is very stable under the conditions of different pH values.

Detailed Description

The following are specific examples of the present invention and further describe the technical solutions of the present invention, but the scope of the present invention is not limited to these examples. All changes, modifications and equivalents that do not depart from the spirit of the invention are intended to be included within the scope thereof.

The synthesis method of the ester-based polyether betaine surfactant comprises the following steps:

1) adding dimethylamine into a pressure reaction kettle, adding a proper amount of alkali catalyst, wherein the alkali catalyst is one or a mixture of sodium hydroxide, potassium hydroxide and monomethylamine, and the addition amount of the alkali catalyst is 0.5-2% of the total mass of all materials; stirring and heating to 120-150 ℃, slowly introducing ethylene oxide, wherein the molar ratio of dimethylamine to ethylene oxide is 1: 2-10, and keeping the temperature for 3-5 hours after the ethylene oxide is introduced to obtain dimethylamine polyoxyethylene ether;

2) putting fatty acid and dimethylamine polyoxyethylene ether into a reaction kettle, wherein the fatty acid is one or a mixture of several of caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid and erucic acid, and the molar ratio of the fatty acid to the dimethylamine polyoxyethylene ether is 1: 1-2; adding a proper amount of catalyst, wherein the catalyst is any one or a mixture of several of p-toluenesulfonic acid, zinc oxide, stannous oxalate and dilute sulfuric acid, and the adding amount of the catalyst is 0.1-2% of the total mass of all materials; heating to 120-180 ℃, and reacting for 6-8 hours under negative pressure to obtain dimethyl polyoxyethylene ether fatty acid ester;

3) putting dimethyl polyoxyethylene ether fatty acid ester, chloroacetate and a solvent into a reaction kettle, wherein the molar ratio of the dimethyl polyoxyethylene ether fatty acid ester to the chloroacetate is 1: 1-1.5, and the addition amount of the solvent is 20-80% of the total mass of all materials; the chloroacetate is sodium chloroacetate or potassium chloroacetate, and the solvent is one or more of water, ethanol, methanol, isopropanol and propylene glycol; heating to 75-105 ℃, and reacting for 6-8 hours to obtain the fatty acid ester polyether betaine.