CN1690176A - A kind of diesel oil low temperature flow improver and preparation method thereof - Google Patents

Abstract

The invention relates to a diesel oil low-temperature flow improver which is prepared by an intermediate product synthesized by an ethylene-vinyl acetate-vinyl alcohol copolymer through an esterification reaction and an in-situ amination reaction and a preparation method thereof, and is characterized in that the ethylene-vinyl acetate-vinyl alcohol copolymer is reacted with C under the action of a catalyst of dodecylbenzene sulfonic acid or p-toluenesulfonic acid_8～18After fatty acid is esterified at the temperature of 130-160 ℃, an aromatic hydrocarbon solvent C is added₉Adding C_6－18The aliphatic amine is aminated in situ to obtain the ethylene-vinyl acetate-C_8～18C of fatty acid ester copolymer of with dodecylbenzenesulfonic acid_6－18The invention not only has good sensitivity to wide-cut diesel oil and mixed diesel oil, but also has the advantages of large proportion of hydrogenated diesel oil and high wax content diesel oilExcellent use effect.

Description

A kind of diesel oil low temperature flow improver and preparation method thereof

technical field

The invention relates to a low-temperature flow improver for diesel oil obtained by using an intermediate product synthesized through an esterification reaction of an ethylene-vinyl acetate-vinyl alcohol copolymer and then through an in-situ amination reaction and a preparation method thereof.

Background technique

The low-temperature performance of diesel is an important index of diesel. Diesel with poor low-temperature performance will affect the normal operation of the diesel engine when the temperature is low. Case flow performance is the commonly used method. At present, the research on diesel low-temperature flow improvement technology is relatively active at home and abroad, especially in economically developed countries, where a variety of polymer-type pour point depressants have been researched and developed. Foreign commercialized products include: the first type is ethylene-vinyl acetate; the second type is ethylene-acrylate copolymer; the third type is compounded with alkenyl succinamide; the fourth type is α- Olefin-Maleic Anhydride Copolymer. 2000, 28 (1).-63-66 pages, the development and performance evaluation of diesel oil low temperature flow improver are introduced in detail. They use ethylene-vinyl acetate-vinyl alcohol type pour point depressant, which has a certain Viscosity of the terpolymer composition, but the pour point depressant generally has a good sensitivity to wide-fraction diesel oil and blended diesel oil, can improve the low-temperature fluidity of diesel oil, and can reduce the cold filter point of diesel oil by 5-10 ° C, while It has poor susceptibility or even no effect on narrow cut diesel and high waxy diesel from some oilfields or refineries.

Invention content:

The purpose of the present invention is to provide a kind of intermediate product that utilizes the copolymer of ethylene-vinyl acetate-vinyl alcohol to be synthesized through esterification reaction in view of the poor susceptibility of diesel oil low-temperature flow improver to high-waxy hydrogenated diesel oil at home and abroad, The diesel oil low temperature flow improver and its preparation method obtained through in-situ amination reaction, the produced pour point depressant can not only effectively reduce the cold filter point and freezing point of diesel oil, improve the yield of light oil, but also have high wax content Diesel also works.

The technical solution of the present invention is: a kind of preparation method of diesel oil low temperature flow improver, its step comprises:

(1) Use the copolymer of ethylene-vinyl acetate-vinyl alcohol to esterify with C _8-18 fatty acids under the action of catalyst at 130-160°C, use xylene as water-carrying agent, and the reaction time is 4-12 hours , control the degree of esterification in the reaction at 50-80%, and remove the solvent under the condition of 1-5 kPa to obtain an intermediate product.

(2) Add aromatic hydrocarbon solvent C ₉ to the intermediate product, and add C _6-18 aliphatic amine for in-situ amination to obtain a low-temperature flow improver for diesel oil.

Its main structural formula is as follows:

Ethylene-vinyl acetate-C _8-18 fatty acid vinyl ester copolymer

C _6-18 fatty amine salt of dodecylbenzenesulfonic acid

Wherein: n, m, x≥8; R ₁ = fatty alkyl group of C _7-17 ; R ₂ = fatty alkyl group of C _6-18 .

Among the intermediate products, ethylene-vinyl acetate-vinyl alcohol copolymer accounts for 20-25% (weight), catalyst accounts for 0.8-1.2% (weight), fatty acid accounts for 30-35% (weight), and water-carrying agent xylene accounts for 45-50% (weight). When carrying out amination, the addition of C ₉ is 55% to 62% (weight) of the intermediate product, and the addition of fatty amine is 2 to 5% (weight) of the intermediate product.

The above-mentioned _C8-18 fatty acid is lauric acid, or stearic acid, or capric acid, or palmitic acid.

The above-mentioned _C6-18 fatty amine is hexylamine, or octylamine, or decylamine, or laurylamine, or tetradecylamine, hexadecylamine, or octadecylamine or mixed amines. Mixed amines include coconut oil amine, or tallow amine or a mixture of coconut oil amine and tallow amine.

The above-mentioned catalyst is dodecylbenzenesulfonic acid or p-toluenesulfonic acid. The catalyst does not come out, and it also acts as a surfactant, which has a synergistic effect on the diesel oil pour point depressing system.

The invention not only has good susceptibility to wide-distillation diesel oil and blended diesel oil, but also has excellent application effect on diesel oil with a large proportion of hydrogenated diesel oil and high wax content, and has achieved good economic and social benefits .

Detailed ways

Example 1

(1) Add 200ml of xylene to a 500ml reactor, then add 78.5g of ethylene-vinyl acetate-vinyl alcohol copolymer, 4g of dodecylbenzenesulfonic acid, and 100g of lauric acid, and heat to reflux at 135°C to react After 10 hours, a mixture with a degree of esterification of about 52% was obtained, and an intermediate product was obtained by distillation under reduced pressure at a vacuum of 2 kPa.

(2) Add 195g of aromatic hydrocarbon solvent C ₉ to the above-mentioned intermediate product, stir evenly, and add about 4g of coconut oil amine under cooling condition to obtain diesel oil low-temperature flow improver 1 ^# of the present invention.

Example 2

(1) Add 180ml of xylene into a 500ml reactor, then add 80g of ethylene-vinyl acetate-vinyl alcohol copolymer, 4g of dodecylbenzenesulfonic acid, and 143g of stearic acid, and heat to reflux at 140°C to react After 8 hours, a mixture with an esterification degree of about 50% was obtained, and an intermediate product was obtained by distillation under reduced pressure at a vacuum of 1.5 kPa.

(2) Add 195g of C ₉ to the above-mentioned intermediate product, stir evenly, and then add about 10g of hexylamine under cooling to obtain diesel low-temperature flow improver 2 ^# of the present invention.

Example 3

(1) Add 200ml of xylene to a 500ml reactor, then add 81.5g of ethylene-vinyl acetate-vinyl alcohol copolymer, 4g of dodecylbenzenesulfonic acid, and 100g of lauric acid, and heat to reflux at 135°C to react After 12 hours, a mixture with a degree of esterification of about 52% was obtained, and an intermediate product was obtained by distillation under reduced pressure at a vacuum of 1.5 kPa.

(2) Add 200g of aromatic hydrocarbon solvent C ₉ to the above-mentioned intermediate product, stir evenly, and add about 4g of tallow amine under cooling condition to obtain diesel oil low temperature flow improver 3 ^# of the present invention.

Example 4

(1) Add 200ml of xylene into a 500ml reactor, then add 81g of ethylene-vinyl acetate-vinyl alcohol copolymer, 4g of dodecylbenzenesulfonic acid, and 100g of lauric acid, and heat to reflux at 135°C to react for 10 hours, a mixture with a degree of esterification of about 60% can be obtained, and an intermediate product can be obtained by distillation under reduced pressure at a vacuum of 3 kPa.

(2) Add 215g of C ₉ to the above-mentioned intermediate product, stir evenly, and then add about 8g of tetradecylamine under cooling condition to obtain diesel oil low temperature flow improver 4 ^# of the present invention.

Example 5

(1) Add 180ml of xylene to a 500ml reactor, then add 85.5g of ethylene-vinyl acetate-vinyl alcohol copolymer, 3g of p-toluenesulfonic acid, and 100g of lauric acid, heat to reflux at 150°C, and react for 12 hours. A mixture with a degree of esterification of about 52% can be obtained, and an intermediate product can be obtained by distillation under reduced pressure at a vacuum of 3 kPa.

(2) Add 210g of aromatic hydrocarbon solvent C ₉ to the above-mentioned intermediate product, stir evenly, and add about 2g of coconut oil amine and 2g of tallow amine under cooling to obtain diesel oil low-temperature flow improver 5 ^# of the present invention.

Example 6

(1) Add 180ml of xylene into a 500ml reactor, then add 85.5g of ethylene-vinyl acetate-vinyl alcohol copolymer, 3g of p-toluenesulfonic acid, 50g of lauric acid and 72g of stearic acid, and heat to 140°C to reflux , reacted for 10 hours to obtain a mixture with a degree of esterification of about 55%, and distilled under reduced pressure at a vacuum of 2.5 kPa to obtain an intermediate product.

(2) Add 205g of aromatic hydrocarbon solvent C ₉ to the above-mentioned intermediate product, stir evenly, and add about 8g of decylamine under cooling condition to obtain low-temperature flow improver 6 ^# for diesel oil of the present invention.

Example 7

(1) Add 200ml of xylene into a 500ml esterification kettle, then add 85g of ethylene-vinyl acetate-vinyl alcohol copolymer, 3g of p-toluenesulfonic acid, and 100g of lauric acid, heat to reflux at 140°C, and react for 10 hours. A mixture with a degree of esterification of about 65% can be obtained, and an intermediate product can be obtained by vacuum distillation at a vacuum of 2.5 kPa.

(2) Add 185g of aromatic hydrocarbon solvent C ₉ to the above-mentioned intermediate product, stir evenly, and add about 6g of octadecylamine under cooling to obtain low-temperature flow improver 7 ^# for diesel oil of the present invention.

Example 8

(1) Add 180ml of xylene into a 500ml reactor, then add 80g of ethylene-vinyl acetate-vinyl alcohol copolymer, 3g of p-toluenesulfonic acid, and 143g of stearic acid, heat to reflux at 140°C, and react for 12 hours. A mixture with a degree of esterification of about 70% can be obtained, and an intermediate product can be obtained by distillation under reduced pressure at a vacuum of 3 kPa.

(2) Add 195g of aromatic hydrocarbon solvent C ₉ to the above-mentioned intermediate product, stir evenly, and add about 6g of hexadecylamine under cooling to obtain diesel oil low-temperature flow improver 8 ^# of the present invention.

Example 9

(1) Add 160ml of xylene into a 500m reactor, then add 78.5g of ethylene-vinyl acetate-vinyl alcohol copolymer, 3g of p-toluenesulfonic acid, and 100g of lauric acid, heat to reflux at 160°C, and react for 8 hours. A mixture with a degree of esterification of about 75% can be obtained, and an intermediate product can be obtained by distillation under reduced pressure at a vacuum of 4 kPa.

(2) Add 200g of aromatic hydrocarbon solvent C ₉ to the above-mentioned intermediate product, stir evenly, and add about 7g of laurylamine under cooling to obtain low-temperature flow improver 9 ^# for diesel oil of the present invention.

In order to illustrate the low-temperature flow improver for diesel oil of the present invention to the experimental effect of reducing the freezing point and cold filter point of diesel oil, table 1 is the experimental result to a certain oil refinery:

Example 10

(1) Add 150ml of xylene into a 500ml reactor, then add 81.5g of ethylene-vinyl acetate-vinyl alcohol copolymer, 4g of p-toluenesulfonic acid, and 95g of capric acid, heat to reflux at 145°C, and react for 10 hours. A mixture with an esterification degree of about 65% can be obtained, and an intermediate product can be obtained by distillation under reduced pressure at a vacuum of 4 kPa.

(2) Add 200g of aromatic hydrocarbon solvent C ₉ to the above-mentioned intermediate product, stir evenly, and add about 4g of coconut oil amine under cooling condition to obtain the diesel oil low-temperature flow improver of the present invention.

Example 11

(1) Add 160ml of xylene into a 500ml reactor, then add 80g of ethylene-vinyl acetate-vinyl alcohol copolymer, 5g of dodecylbenzenesulfonic acid, and 120g of palmitic acid, heat to reflux at 155°C, and react After 11 hours, a mixture with a degree of esterification of about 55% was obtained, and an intermediate product was obtained by distillation under reduced pressure at a vacuum of 3 kPa.

(2) Add 200g of aromatic hydrocarbon solvent C ₉ to the above-mentioned intermediate product, stir evenly, and add about 6g of laurylamine under cooling to obtain the low-temperature flow improver for diesel oil of the present invention.

In order to illustrate the low-temperature flow improver for diesel oil of the present invention to the experimental effect of reducing the freezing point and cold filter point of diesel oil, table 1 is the experimental result to a certain oil refinery: sample number Freezing point after adding additives (°C) Cold filtration point after adding additives (°C) 1 ^# -42 -9 2 ^# -41 -9 3 ^# -42 -8 4 ^# -45 -8 5 ^# -41 -10 6 ^# -47 -11 7 ^# -47 -5 8 ^# -42 -5 9 ^# -41 -4 A pour point depressant in Nanjing -20 0 A pour point depressant in Yixing, Jiangsu -twenty two -1

Note: The diesel sample is hydrotreated 0 ^# diesel from the refinery, the blank freezing point is 0°C, and the cold filter point is 4°C. The dosage is all 0.8‰ (percentage by weight).

Claims (7)

1. a preparation method of diesel oil low temperature flow improver, characterized in that: (1) Use ethylene-vinyl acetate-vinyl alcohol copolymer to esterify with C _8-18 fatty acids under the action of a catalyst at 130-160°C, use xylene as a water-carrying agent, and the reaction time is 4-12 hours , control the degree of esterification in the reaction at 50-80%, and remove the solvent under the condition of 1-5 kPa to obtain an intermediate product; (2) Add aromatic hydrocarbon solvent C ₉ to the intermediate product, and add C _6-18 aliphatic amine for in-situ amination to obtain a low-temperature flow improver for diesel oil. 2. the preparation method of a kind of diesel oil low temperature flow improver according to claim 1 is characterized in that: ethylene-vinyl acetate-vinyl alcohol copolymer accounts for 20～25% (weight), and catalyst accounts for 0.8～1.2% ( weight), the fatty acid accounts for 30-35% (weight), and the water-carrying agent xylene accounts for 45-50% (weight). 3. the preparation method of a kind of diesel oil low-temperature flow improver according to claim 1 is characterized in that: when carrying out amination, aromatic hydrocarbon solvent C ₉ add-on is 55%～62% (weight) of intermediate product, fat The amount of amine added is 2-5% (weight) of the intermediate product. 4. The preparation method of a low-temperature flow improver for diesel oil according to claim 1, characterized in that: the catalyst is dodecylbenzenesulfonic acid or p-toluenesulfonic acid. 5. The preparation method of a low-temperature flow improver for diesel oil according to claim 1, characterized in that: the fatty acid of C _8-18 is lauric acid, or stearic acid, or capric acid, or palmitic acid. 6. the preparation method of a kind of diesel oil cold flow improver according to claim 1 is characterized in that: the aliphatic amine of C _8-18 is hexylamine, or octylamine, or decylamine, or laurylamine, or tetradecylamine Amine, or cetylamine, or octadecylamine, or coconut oil amine, or tallow amine, or a mixture of coconut oil amine and tallow amine. 7. A kind of diesel oil low temperature flow improver prepared by the preparation method of a kind of diesel low temperature flow improver according to claim 1, characterized in that: Its main structural formula is as follows: Ethylene-vinyl acetate-C _8-18 fatty acid vinyl ester copolymer

C _6-18 fatty amine salt of dodecylbenzenesulfonic acid Wherein: n, m, x≥8; R ₁ = fatty alkyl group of C _7-17 ; R ₂ = fatty alkyl group of C _6-18 .