CN108977239B

CN108977239B - Diesel oil lubrication improver and preparation method thereof

Info

Publication number: CN108977239B
Application number: CN201810907146.2A
Authority: CN
Inventors: 邓俊辉; 严斌; 胡涛英; 熊靓
Original assignee: Ningbo Guangchangda New Material Co ltd
Current assignee: GUANGCHANGDA NEW MATERIAL TECHNOLOGY SERVICE (SHENZHEN) Co.,Ltd.
Priority date: 2018-08-10
Filing date: 2018-08-10
Publication date: 2020-09-08
Anticipated expiration: 2038-08-10
Also published as: CN108977239A

Abstract

The invention relates to a diesel oil lubrication improver and a preparation method thereof. The preparation method of the diesel oil lubrication improver comprises the following steps: carrying out esterification reaction on unsaturated fatty acid and polyalcohol at 180-220 ℃ under the catalysis of alkali, and continuously introducing protective gas in the esterification reaction process until the acid value of a reaction system is reduced to 15-25 mgKOH/g, and stopping the reaction to obtain a crude product; distilling the crude product under reduced pressure until the acid value of the crude product is reduced to 0.5 mgKOH/g-2 mgKOH/g; cooling the crude product, mixing the cooled crude product with lower alcohol or a water solution thereof to obtain a mixture, and then carrying out ion exchange on the mixture and strong acid type ion exchange resin; and distilling the mixture subjected to ion exchange to remove water and lower alcohol to obtain the diesel oil lubrication improver. The diesel oil lubrication improver prepared by the method has low acid value, and when the diesel oil lubrication improver is used for diesel oil, the diesel oil can keep better oil-water separation performance and has better lubricity.

Description

Diesel oil lubrication improver and preparation method thereof

Technical Field

The invention relates to the technical field of diesel oil functional additives, in particular to a diesel oil lubrication improver and a preparation method thereof.

Background

The diesel oil lubricity improver is an important additive for improving the diesel oil lubricity, the diesel oil lubricity improver is divided into a fatty acid type and a fatty acid ester type, at present, domestic diesel oil mainly adopts the fatty acid type, but the fatty acid type diesel oil lubricity improver has more problems in use, such as: fatty acid type diesel lubricity improvers affect the acidity of diesel fuel and have compatibility problems with other additives to diesel fuel, particularly diesel detergents. The fatty acid reacts with the nitrogen-containing compounds within the diesel detergent, resulting in a dual reduction in antiwear and detergent properties. The fatty acid ester type well avoids the problems, belongs to a fatty acid type improved product, has better lubricating effect on diesel oil than the fatty acid type under the condition of the same dosage, has low acid value, cannot influence the acidity of the diesel oil after being added, cannot react with other diesel oil additives, and is an optimal substitute product of the fatty acid type.

At present, fatty acid ester type diesel lubricity improver is mainly produced by adopting fatty acid and polyalcohol under the catalytic action of metal hydroxide, but the current preparation process has the defects that: on one hand, the acid value of the product is still high, the acid value of the diesel oil is easy to exceed the standard, and the rust damage to a diesel engine cannot be avoided after long-term use; on the other hand, the diesel oil lubrication improver prepared by fatty acid and polyhydric alcohol under the catalytic action of metal hydroxide can seriously damage the oil-water separation performance of diesel oil when being added into the diesel oil, even block an oil filling gun and an engine filter screen when being serious, influence the normal use of the engine, and influence the diesel oil lubrication performance and the exhaust emission of diesel engines and automobiles.

Disclosure of Invention

Therefore, the preparation method of the diesel oil lubrication improver is needed, the acid value of the diesel oil lubrication improver prepared by the method is low, and when the diesel oil lubrication improver is used for diesel oil, the diesel oil can keep good oil-water separation performance and has good lubricity.

In addition, the diesel oil lubrication improver prepared by the preparation method of the diesel oil lubrication improver is also provided.

A preparation method of a diesel oil lubrication improver comprises the following steps:

under the condition of introducing protective gas, carrying out esterification reaction on unsaturated fatty acid and polyalcohol at 180-220 ℃ under the catalysis of alkali, and stopping the reaction until the acid value of a reaction system is reduced to 15-25 mgKOH/g to obtain a crude product;

maintaining the temperature at 180-220 ℃, and distilling the crude product under reduced pressure until the acid value of the crude product is reduced to 0.5-2 mgKOH/g;

cooling the crude product, mixing the cooled crude product with lower alcohol or a water solution thereof to obtain a mixture, and then carrying out ion exchange on the mixture and strong acid type ion exchange resin; and

and drying the mixture subjected to ion exchange to obtain the diesel oil lubrication improver.

In one embodiment, the unsaturated fatty acid is at least one selected from oleic acid, tall oil fatty acid, soybean oil fatty acid and palm oil fatty acid, and the saturated fatty acid content in the unsaturated fatty acid is not more than 2.5% by mass;

and/or, the polyalcohol is at least one selected from glycerol, pentaerythritol, sorbitol and xylitol;

and/or, the alkali is selected from at least one of sodium hydroxide, potassium hydroxide and calcium hydroxide;

and/or, the lower alcohol is selected from methanol, ethanol or isopropanol.

In one embodiment, the mass ratio of the unsaturated fatty acid to the polyhydric alcohol is 2:1 to 8.7: 1.

In one embodiment, the mass ratio of the unsaturated fatty acid to the base is 500:1 to 1300: 1.

In one embodiment, the strong acid type ion exchange resin is at least one selected from the group consisting of a sulfonic acid type ion exchange resin, an acrylic acid type ion exchange resin, and a hydrogen type ion exchange resin.

In one embodiment, the mass ratio of the crude product to the lower alcohol or the aqueous solution thereof is 2:1 to 3: 1.

In one embodiment, the mass ratio of the mixture to the strong acid type ion exchange resin is 1: 0.015-1: 0.035.

In one embodiment, the step of cooling the crude product and mixing with a lower alcohol or an aqueous solution thereof to obtain a mixture comprises cooling the crude product to a temperature of 30 ℃ to 40 ℃.

In one embodiment, the step of drying the ion-exchanged mixture to obtain the diesel lubrication improver specifically comprises:

distilling the mixture at 90-100 ℃ under normal pressure in the protective gas atmosphere to recover lower alcohol; and

and carrying out reduced pressure distillation on the mixture under the conditions that the vacuum degree is lower than-0.09 MPa and the temperature is 90-100 ℃ to obtain the diesel oil lubrication improver.

A diesel oil lubrication improver is prepared by the preparation method of the diesel oil lubrication improver.

The preparation method of the diesel oil lubrication improver comprises the steps of firstly reacting unsaturated fatty acid with polyalcohol under the catalysis of alkali, continuously introducing protective gas in the reaction process to take out water generated by the reaction until the acid value of a reaction system is reduced to 15 mgKOH/g-25 mgKOH/g, and reducing the acid value of a crude product to 0.5 mgKOH/g-2 mgKOH/g by adopting a reduced pressure distillation mode, so that the diesel oil lubrication improver with a lower acid value can be prepared; the crude product is mixed with lower alcohol or aqueous solution thereof and then is subjected to ion exchange with strong acid type ion exchange resin, the crude product can fully perform ion exchange with the strong acid type ion exchange resin in the environment that the solvent is the lower alcohol or the aqueous solution thereof, the content of metal ions in the product is reduced, and fatty acid salt generated by reaction of unsaturated fatty acid in the diesel oil lubrication improver and an alkali catalyst is removed, so that the influence of the fatty acid salt in the diesel oil lubrication improver on the oil-water separation performance of the diesel oil is avoided, and the phenomenon of blocking an oil filling gun and an engine filter screen caused by excessive fatty acid salt can be effectively avoided.

Drawings

Fig. 1 is a process flow diagram of a method for producing a diesel lubrication improver according to an embodiment.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, but rather should be construed as broadly as the present invention is capable of modification in various respects, all without departing from the spirit and scope of the present invention.

Referring to fig. 1, a method for preparing a diesel lubricity improver according to an embodiment includes the steps of:

s110, carrying out esterification reaction on unsaturated fatty acid and polyhydric alcohol under the catalysis of alkali at 180-220 ℃ to obtain a crude product.

In one embodiment, the unsaturated fatty acid is at least one selected from the group consisting of oleic acid, tall oil fatty acid, soybean oil fatty acid, and palm oil fatty acid, and the saturated fatty acid content in the unsaturated fatty acid is not more than 2.5% by weight.

In one embodiment, the polyol is selected from at least one of glycerol, pentaerythritol, sorbitol, and xylitol.

In one embodiment, the base is a metal hydroxide. Further, the alkali is at least one selected from the group consisting of sodium hydroxide, potassium hydroxide and calcium hydroxide.

Further, the mass ratio of the unsaturated fatty acid to the polyhydric alcohol is 2: 1-8.7: 1. Further, the mass ratio of unsaturated fatty acid to polyol may also be 4:1, 5:1 or 7: 1.

Further, the mass ratio of the unsaturated fatty acid to the base is 500: 1-1300: 1. Further, the mass ratio of the unsaturated fatty acid to the base may also be 800:1 or 1000: 1.

In one embodiment, the protective gas is continuously introduced during the esterification reaction, and the esterification reaction is stopped to obtain a crude product when the acid value of the reaction system is reduced to 15mgKOH/g to 25 mgKOH/g. Protective gas is continuously introduced in the esterification reaction process, and the protective gas can also take out water generated by the reaction, so that the esterification reaction is facilitated.

Further, the protective gas is selected from at least one of nitrogen and argon.

S120, keeping the temperature at 180-220 ℃, and distilling the crude product under reduced pressure until the acid value of the crude product is reduced to 0.5-2 mgKOH/g.

In one embodiment, the degree of vacuum of the system is controlled to-0.5 MPa when the distillation under reduced pressure is carried out.

S130, cooling the crude product, mixing the cooled crude product with lower alcohol or aqueous solution thereof to obtain a mixture, and then carrying out ion exchange on the mixture and strong acid type ion exchange resin to remove metal ions.

In one embodiment, the crude product is cooled to 30 ℃ to 40 ℃ and then mixed with a lower alcohol or an aqueous solution thereof to obtain a mixture. Further, the mass ratio of the crude product to the lower alcohol or the water solution thereof is 2: 1-3: 1.

Further, the purity of the lower alcohol is 90-99%. The purity of the lower alcohol may also be 95%.

In one embodiment, the lower alcohol is selected from methanol, ethanol or isopropanol.

In one embodiment, the crude product is mixed with an aqueous solution of a lower alcohol to provide a mixture. Further, the mass concentration of the aqueous solution of the lower alcohol is 80% to 100%, and it is understood that the lower alcohol is not added with water when the mass concentration of the aqueous solution of the lower alcohol is 100%.

Further, the mass ratio of the mixture to the strong acid type ion exchange resin is 1: 0.015-1: 0.035.

Further, the time for the mixture to carry out ion exchange with the strong acid type ion exchange resin is 1-4 h.

In one embodiment, the metal ion content of the mixture after ion exchange with the strong acid type ion exchange resin is reduced to 50ppm or less.

And S140, drying the mixture subjected to ion exchange to obtain the diesel oil lubrication improver.

In one embodiment, the drying of the ion-exchanged mixture is aimed at removing the lower alcohol and water.

In one embodiment, the step of drying the ion-exchanged mixture specifically comprises:

and S141, distilling the mixture at 90-100 ℃ under normal pressure in a protective gas atmosphere to recover the lower alcohol.

In one embodiment, the protective gas is continuously introduced into the reaction system during atmospheric distillation of the mixture.

And S142, carrying out reduced pressure distillation on the mixture under the conditions that the vacuum degree is lower than-0.09 MPa and the temperature is 90-100 ℃ to obtain the diesel oil lubrication improver.

In one embodiment, after the protective gas is stopped being introduced into the reaction system, the vacuum degree is vacuumized to be lower than-0.09 MPa, and the mixture is subjected to reduced pressure distillation.

S150, filtering the diesel oil lubrication improver.

In one embodiment, the diesel lubricity improver is filtered to remove filter residue.

In addition, the crude product is mixed with lower alcohol or water solution thereof before ion exchange, so that the solubility of metal ions can be increased, the ion exchange is facilitated, and the removal of the metal ions is facilitated.

In other embodiments, step S150 may be omitted.

The diesel oil lubrication improver of one embodiment is prepared by the preparation method of the diesel oil lubrication improver.

The diesel oil lubrication improver prepared by the preparation method of the diesel oil lubrication improver is applied to diesel oil antiwear.

The following are descriptions of specific examples, and unless otherwise specified, the following examples contain no other components not specifically mentioned except for inevitable impurities.

Example 1

Pumping 1200Kg of soybean oil fatty acid and 300Kg of pentaerythritol into a reaction kettle by a pump, adding 1.25Kg of potassium hydroxide catalyst into the reaction kettle, continuously introducing nitrogen into the reaction kettle, and stirring the materials in the reaction kettle for 30min until the materials are uniformly mixed; heating the reaction kettle to 200 ℃ to enable the soybean oil fatty acid and pentaerythritol to have esterification reaction, and stopping the reaction after the reaction lasts for 6 hours until the acid value of the reaction system is reduced to 22 mgKOH/g; then carrying out reduced pressure distillation at the temperature of 200 ℃ and the vacuum degree of-0.05 MPa, stopping reduced pressure distillation until the acid value is 0.8mgKOH/g, cooling to 40 ℃, adding ethanol into the reaction kettle according to the mass ratio of the crude product to the ethanol of 3:1, stirring uniformly, adding 30Kg of acrylic acid type ion exchange resin, and carrying out ion exchange to remove metal ions in the product, wherein the ion exchange time is 2 hours; and then, distilling under normal pressure at the temperature of 100 ℃ and under the nitrogen atmosphere to recover ethanol, then distilling under reduced pressure at the vacuum degree of-0.09 MPa and the temperature of 100 ℃ to remove other low-boiling-point substances in the mixture, and filtering to remove filter residues to obtain the diesel oil lubrication improver.

Example 2

Pumping 1000Kg of oleic acid and 200Kg of glycerol into a reaction kettle by a pump, adding 1Kg of sodium hydroxide catalyst into the reaction kettle, continuously introducing nitrogen into the reaction kettle, and stirring the materials in the reaction kettle for 30min until the materials are uniformly mixed; heating the reaction kettle to 190 ℃ to enable oleic acid and glycerol to perform esterification reaction, and stopping the reaction when the acid value of the reaction system is reduced to 15mgKOH/g after the reaction is carried out for 10 hours; then carrying out reduced pressure distillation at the temperature of 190 ℃ and the vacuum degree of-0.05 MPa, stopping reduced pressure distillation until the acid value is 0.5mgKOH/g, cooling to 35 ℃, adding 95% ethanol into the reaction kettle according to the mass ratio of the crude product to 95% ethanol of 2:1, stirring uniformly, adding 15Kg of sulfonic acid type ion exchange resin for ion exchange to remove metal ions, wherein the ion exchange time is 4 hours; and then, carrying out normal pressure distillation at the temperature of 90 ℃ under the nitrogen atmosphere to recover ethanol, then carrying out reduced pressure distillation at the vacuum degree of-0.09 MPa and the temperature of 90 ℃ to remove water and other low-boiling-point substances in the mixture, and filtering to remove filter residues to obtain the diesel oil lubrication improver.

Example 3

Pumping 1400Kg of tall oil fatty acid and 200Kg of xylitol into a reaction kettle by a pump, adding 1.1Kg of calcium hydroxide catalyst into the reaction kettle, continuously introducing nitrogen into the reaction kettle, and stirring the materials in the reaction kettle for 30min until the materials are uniformly mixed; heating the reaction kettle to 180 ℃ to enable tall oil fatty acid and xylitol to have esterification reaction, and stopping the reaction when the acid value of the reaction system is reduced to 20mgKOH/g after the reaction is carried out for 10 hours; then, carrying out reduced pressure distillation at the temperature of 180 ℃ and the vacuum degree of-0.05 MPa until the acid value is 1.5mgKOH/g, and stopping the reduced pressure distillation; cooling to 35 ℃, adding 90% methanol into the reaction kettle according to the mass ratio of the crude product to 90% methanol being 3:1, stirring uniformly, and then adding 45Kg of hydrogen type ion exchange resin for ion exchange to remove metal ions, wherein the ion exchange time is 3 h; and then, carrying out normal pressure distillation at the temperature of 90 ℃ under the nitrogen atmosphere condition to recover the methanol, carrying out reduced pressure distillation at the vacuum degree of-0.09 MPa and the temperature of 90 ℃ to remove water and other low-boiling-point substances in the mixture, and filtering to remove filter residues to obtain the diesel oil lubrication improver.

Example 4

Pumping 750Kg of palm oil fatty acid and 250Kg of sorbitol into a reaction kettle by a pump, adding 1.25Kg of sodium hydroxide catalyst into the reaction kettle, continuously introducing nitrogen into the reaction kettle, and stirring the materials in the reaction kettle for 30min until the materials are uniformly mixed; heating the reaction kettle to 210 ℃ to enable the palm oil fatty acid and the sorbitol to have esterification reaction, and stopping the reaction after the reaction lasts for 8 hours until the acid value of the reaction system is reduced to 25 mgKOH/g; then, carrying out reduced pressure distillation at the temperature of 210 ℃ and the vacuum degree of-0.05 MPa, and stopping reduced pressure distillation when the acid value is 1 mgKOH/g; after cooling to a temperature of 30 ℃, the crude product was mixed with 95% isopropanol 2:1, adding 95 percent isopropanol by mass, uniformly stirring, and then adding 15Kg of sulfonic acid type ion exchange resin for ion exchange to remove metal ions, wherein the ion exchange time is 2.5 hours; and then, carrying out normal pressure distillation at the temperature of 95 ℃ under the nitrogen atmosphere condition to recover isopropanol, carrying out reduced pressure distillation at the vacuum degree of-0.09 MPa and the temperature of 95 ℃, removing water and other low-boiling-point substances in the mixture, and filtering to remove filter residues to obtain the diesel oil lubrication improver.

Example 5

Pumping 1000Kg of oleic acid and 200Kg of glycerol into a reaction kettle by a pump, adding 1Kg of sodium hydroxide catalyst into the reaction kettle, continuously introducing nitrogen into the reaction kettle, and stirring the materials in the reaction kettle for 30min until the materials are uniformly mixed; heating the reaction kettle to 190 ℃ to enable oleic acid and glycerol to perform esterification reaction, and stopping the reaction when the acid value of the reaction system is reduced to 15mgKOH/g after the reaction is carried out for 10 hours; cooling to 35 ℃, adding 95% ethanol according to the mass ratio of the crude product to 95% ethanol of 2:1, stirring uniformly, and then adding 15Kg of sulfonic acid type ion exchange resin for ion exchange to remove metal ions, wherein the ion exchange time is 4 h; and then distilling and recovering ethanol at 90 ℃ under the condition of nitrogen atmosphere under normal pressure, then distilling under reduced pressure at the vacuum degree of-0.09 MPa and the temperature of 90 ℃, removing water and other low-boiling-point substances in the mixture, and filtering to remove filter residues to obtain the diesel oil lubrication improver.

Example 6

Pumping 1000Kg of oleic acid and 200Kg of glycerol into a reaction kettle by a pump, adding 1Kg of sodium hydroxide catalyst into the reaction kettle, continuously introducing nitrogen into the reaction kettle, and stirring the materials in the reaction kettle for 30min until the materials are uniformly mixed; heating the reaction kettle to 190 ℃ to enable oleic acid and glycerol to perform esterification reaction, and stopping the reaction when the acid value of the reaction system is reduced to 15mgKOH/g after the reaction is carried out for 10 hours; and then, carrying out reduced pressure distillation at the temperature of 190 ℃ and the vacuum degree of-0.05 MPa until the acid value is 0.5mgKOH/g, and stopping the reduced pressure distillation to obtain the diesel oil lubrication improver.

The metal content, acid value, demulsification property and abrasion resistance of the diesel oil lubrication improver prepared in the examples 1 to 6 were measured, and the results are shown in table 1.

Wherein, the metal content: testing was carried out according to the method specified in GB/T17476 determination of additive elements, wear metals and contaminants in used lubricating oil and certain elements in base oil (inductively coupled plasma emission Spectroscopy); meets the regulation that the metal content of Q/SHCG 57-2014 technical requirement of diesel antiwear agent does not exceed 50 ppm.

Acid value: measuring according to GB/T7304-; meets the requirement of Q/SHCG 57-2014 on the technical requirement of diesel antiwear additive that the acid value of additivated diesel oil is less than or equal to 2 mgKOH/g.

Demulsification property of additive diesel oil: the demulsification test method of the diesel antiwear agent is tested according to appendix C (normative appendix) of Q/SHCG 57-2014; the diesel oil-water separation performance is qualified when the diesel oil-water separation agent meets the requirements of Q/SHCG 57-2014 diesel oil antiwear agent technical requirements and no less than 18ml of water (the total water amount is 20ml) is separated within 15 minutes of standing.

Abrasion resistance: the measurement is carried out according to SH/T0765 & 2005 & ltDiesel lubricity evaluation method (high-frequency reciprocating testing machine method) & gt; meets the specification of Q/SHCG 57-2014 technical requirement of diesel antiwear agent that the additive diesel WS is 1.4/mum and is less than or equal to 420).

TABLE 1

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The preparation method of the diesel oil lubrication improver is characterized by comprising the following steps:

under the condition of introducing protective gas, carrying out esterification reaction on unsaturated fatty acid and polyol under the catalysis of metal hydroxide at 190-220 ℃, and stopping the reaction until the acid value of a reaction system is reduced to 15-25 mgKOH/g, thus obtaining a crude product;

keeping the temperature at 190-220 ℃, and distilling the crude product under reduced pressure until the acid value of the crude product is reduced to 0.5-2 mgKOH/g;

drying the mixture subjected to ion exchange to obtain the diesel oil lubrication improver;

the mass content of saturated fatty acid in the unsaturated fatty acid is not more than 2.5%;

the mass ratio of the unsaturated fatty acid to the polyhydric alcohol is 4: 1-8.7: 1;

the mass ratio of the unsaturated fatty acid to the metal hydroxide is 500: 1-1300: 1;

the mass ratio of the mixture to the strong acid type ion exchange resin is 1: 0.015-1: 0.035;

the polyhydric alcohol is at least one selected from glycerol, pentaerythritol, sorbitol and xylitol.

2. The method for producing a diesel lubrication improver according to claim 1, wherein the unsaturated fatty acid is at least one selected from the group consisting of oleic acid, tall oil fatty acid, soybean oil fatty acid, and palm oil fatty acid.

3. The method of producing a diesel lubrication improver according to claim 1, wherein the metal hydroxide is at least one selected from the group consisting of sodium hydroxide, potassium hydroxide, and calcium hydroxide.

4. A process for the preparation of a diesel lubrication improver according to claim 1 or 2, wherein the lower alcohol is selected from methanol, ethanol or isopropanol.

5. The method for producing a diesel lubrication improver according to claim 1, wherein the strong acid type ion exchange resin is at least one selected from the group consisting of a sulfonic acid type ion exchange resin, an acrylic acid type ion exchange resin, and a hydrogen type ion exchange resin.

6. The method for producing a diesel lubrication improver according to claim 1, wherein the mass ratio of the crude product to the lower alcohol or the aqueous solution thereof is 2:1 to 3: 1.

7. The method for producing a diesel lubrication improver according to claim 1, wherein the step of cooling the crude product and mixing the cooled crude product with a lower alcohol or an aqueous solution thereof to obtain a mixture comprises cooling the crude product to 30 to 40 ℃.

8. The method for preparing the diesel lubrication improver according to claim 1, wherein the step of drying the ion-exchanged mixture to obtain the diesel lubrication improver specifically comprises:

9. A diesel oil lubrication improver characterized by being produced by the production method for a diesel oil lubrication improver according to any one of claims 1 to 8.