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CN-121736827-B - Acid ester composite type diesel antiwear agent and preparation method thereof

CN121736827BCN 121736827 BCN121736827 BCN 121736827BCN-121736827-B

Abstract

The invention provides an acid ester composite type diesel antiwear agent and a preparation method thereof, belonging to the technical field of diesel additives, and comprising the following steps of S1, preparing a silanization solid acid catalyst; S2, preparing C18 polyol ester, S3, mixing the acid type antiwear component and the C18 polyol ester, heating and stirring, adding the tetrahydropyrazolpyridine derivative and the diluent, continuously stirring, cooling, and filtering to obtain the acid ester compound type diesel antiwear agent. The invention can improve the lubricity and the wear resistance of the low-sulfur diesel under the condition of lower additive amount, and has low corrosiveness and good oxidation stability.

Inventors

  • WANG ZHAOGUANG
  • CHEN HUAXIN
  • WU ZHENGYANG

Assignees

  • 宜兴市星光宝亿化工有限公司

Dates

Publication Date
20260508
Application Date
20260227

Claims (9)

  1. 1. The preparation method of the acid ester composite type diesel oil antiwear agent is characterized by comprising the following steps: S1, adding activated biochar into concentrated sulfuric acid, magnetically stirring, sulfonating in an oven at the temperature of 80 ℃, cooling, washing, vacuum drying, adding into a mixed system containing hexamethyldisilazane, stirring, reacting, filtering, drying to obtain a silanized solid acid catalyst, adding 10-15 parts by mass of walnut shell powder into 60-100 parts by volume of deionized water, magnetically stirring for 40-60 min, filling into a polytetrafluoroethylene lining reaction kettle, carrying out hydrothermal carbonization at the temperature of 180-190 ℃ for 18-24 h, cooling, filtering, adding 300-500 parts by volume of ZnCl 2 solution with the concentration of 2-3 wt% into the mixture, mixing and stirring for 2-3 h, heating at the temperature of 80 ℃ for drying for 8-12 h, placing into a tubular furnace under the protection of nitrogen atmosphere, heating to 500 ℃ at the temperature of 5 ℃ per min, preserving 2h, cooling, soaking in 60-80 parts by volume of hydrochloric acid solution with the concentration of 2mol/L for 5-6 h, washing with deionized water for 3-5 times, and drying for 12h to obtain the catalyst; S2, continuously stirring the C18 light floating oil fatty acid, the polyol, the silanization solid acid catalyst and the dimethylbenzene under the protection of nitrogen, heating to 140-160 ℃ for heat preservation, continuously heating to 180-190 ℃ for reaction, cooling to 90-100 ℃, filtering, performing reduced pressure distillation on the filtrate, and cooling to obtain C18 polyol ester; S3, mixing the acid type antiwear component and the C18 polyol ester, heating and stirring, adding the tetrahydropyrazolpyridine derivative and the diluent, continuously stirring, cooling, and filtering to obtain the acid ester compound type diesel antiwear agent, wherein the molecular structural formula of the tetrahydropyrazolpyridine derivative is as follows: ; the diluent is 0# diesel oil.
  2. 2. The preparation method of the acid ester composite type diesel antiwear agent according to claim 1 is characterized in that the mixed system containing hexamethyldisilazane is obtained by mixing and stirring 0.27-0.3 part by mass of ethanol, 0.6-0.8 part by mass of hexamethyldisilazane and 30 parts by volume of toluene for 5-10 min.
  3. 3. The preparation method of the acid ester composite type diesel antiwear agent according to claim 1 is characterized in that in the step S1, 6-10 parts by mass of activated biochar is added into 50-60 parts by volume of 98wt% sulfuric acid solution, magnetically stirred for 10-15 min, then the mixture is placed in an 80 ℃ oven for sulfonation for 16-18 h, cooled, washed with deionized water for 3-5 times, dried in vacuum for 12-16 h at 70-80 ℃, then added into a mixed system containing hexamethyldisilazane, stirred for 20-24 h at 45-55 ℃, filtered to recover solids, and dried for 12-16 h at 80 ℃ to obtain the silanized solid acid catalyst.
  4. 4. The method for preparing the acid ester composite type diesel oil antiwear agent according to claim 1, wherein in the step S2, 83-120 parts by mass of C18 light oil slick fatty acid and 7-13 parts by mass are mixed Adding polyol into a reaction kettle, uniformly mixing, adding 3-6 parts by mass of a silanization solid acid catalyst and 30-50 parts by volume of dimethylbenzene, continuously and mechanically stirring at 400rpm under the protection of nitrogen, heating to 140-160 ℃, preserving heat for 0.5-1 h, continuously heating to 180-190 ℃ for reacting for 5-8 h, utilizing dimethylbenzene for azeotropic dehydration in the reaction process, cooling to 90-100 ℃ after the reaction is finished, filtering, carrying out reduced pressure distillation on the filtrate under the conditions of 80-90 ℃ and minus 0.08-0.09 MPa, and cooling to room temperature to obtain C18 polyol ester.
  5. 5. The method for preparing the acid ester composite type diesel antiwear agent according to claim 1, wherein the polyol is one or more of glycerol and ethylene glycol.
  6. 6. The preparation method of the acid ester composite type diesel oil antiwear agent according to claim 1 is characterized in that the tetrahydropyrazolpyridine derivative is prepared by adding 2-3 parts by mass of hydrazine hydrate and 6.3-7 parts by mass of ethyl acetoacetate into 125 parts by volume of absolute ethyl alcohol, magnetically stirring for 30-50 min at 30 ℃, sequentially adding 3.2-3.6 parts by mass of p-methoxybenzaldehyde and 7.3-8 parts by mass of ammonium acetate, continuously heating to 70 ℃ for reflux reaction for 4-8 h, cooling to room temperature after the reaction is finished, adding 250 parts by volume of deionized water into a system, continuously stirring for 30min at room temperature, filtering and separating the obtained solid, sequentially washing with deionized water and acetone, and drying under vacuum for 8-12 h.
  7. 7. The preparation method of the acid ester composite type diesel oil antiwear agent according to claim 1, wherein the acid type antiwear component is obtained by adding C18 light oil floating acid, 12-hydroxystearic acid and C 36 fatty acid dimer acid into a reaction kettle, and heating and stirring at 300rpm for 20-30 min at 80 ℃.
  8. 8. The method for preparing the acid ester composite type diesel antiwear agent according to claim 1, wherein in the step S3, an acid type antiwear component and a C18 polyol ester are mixed, stirred for 30-40 min at 80 ℃, then a tetrahydropyrazolpyridine derivative and a diluent are added, stirring is continued for 1-2 h at 70-80 ℃, cooling is carried out to 55-60 ℃, and after hot filtration is carried out through a 5 μm filter element, cooling is carried out to room temperature, thus obtaining the acid ester composite type diesel antiwear agent.
  9. 9. The acid ester composite type diesel antiwear agent is characterized by being prepared by a preparation method of the acid ester composite type diesel antiwear agent according to any one of claims 1-8, and comprises the following raw materials, by mass, 14-23 parts of acid type antiwear component, 36-55 parts of C18 polyol ester, 6-7 parts of tetrahydropyrazolpyridine derivative and 25-30 parts of diluent; the acid type antiwear component comprises the following raw materials, by mass, 3-6 parts of C18 light oil slick fatty acid, 4-10 parts of 12-hydroxystearic acid and 4-10 parts of C36 fatty acid dimer acid.

Description

Acid ester composite type diesel antiwear agent and preparation method thereof Technical Field The invention relates to the technical field of diesel additives, in particular to an acid ester composite type diesel antiwear agent and a preparation method thereof. Background In order to improve the exhaust emission quality of diesel engines, deep processing diesel oil refining technology is adopted by fuel oil manufacturers to produce clean diesel oil characterized by low sulfur content and low aromatic hydrocarbon content, and the diesel oil has the characteristics of low sulfur, low aromatic content, high cetane number and lighter fraction. Meanwhile, as the crude oil resources have remarkable trends of high sulfur, high acid, high salt and heavy weight, more severe hydrogenation process conditions are generally adopted in the clean diesel oil production process, a large amount of polycyclic and bicyclic aromatic hydrocarbons and polar compounds containing oxygen, nitrogen and the like in the diesel oil are removed, the natural lubricity of the diesel oil is obviously weakened although the content of sulfur and aromatic hydrocarbons is favorably reduced, the abrasion of precise parts such as high-pressure oil pumps, oil injectors and the like is easily caused, and the service life is shortened. Practice shows that in the deep desulfurization process, sulfur-containing, oxygen-containing and partial polar components which originally endow diesel oil with certain lubricating function are removed at the same time, so that the lubricating performance of low-sulfur diesel oil is obviously reduced, and clean diesel oil with poor lubricating property becomes an important factor for limiting the reliable operation of the diesel engine. The anti-wear agent is added into the diesel oil, is one of the simple and effective lubricity improving means at present, and has the action mechanism that the interfacial active compound selectively adsorbs the metal surface, and an adsorption film or a reaction film is formed on the metal surface to isolate the metal from direct contact, thereby remarkably reducing the abrasion under the condition of mild or even moderate load. The existing diesel antiwear agent mainly comprises two main categories, namely fatty acid antiwear agents, wherein the fatty acid antiwear agents are easy to obtain in raw materials and relatively low in cost, the acid value of the fatty acid antiwear agents is higher, the total acidity of diesel oil is easy to be obviously improved after the fatty acid antiwear agents are added, corrosion risks can be further amplified for diesel oil with higher acidity, and meanwhile, the acidity of the diesel oil is likely to be close to or exceed the current national and enterprise standards under the condition of the addition amount required for achieving the target lubricity, and acid-base reaction is easy to occur when the diesel oil is compatible with alkaline additives such as detergents, so that insoluble sediments are generated to block a filter screen, and the hidden danger of damaging the normal operation of an engine exists. The other type is an ester type antiwear agent, which has low acid value, basically has no adverse effect on the acidity of diesel oil, generally does not corrode equipment and pipelines of a transmission and distribution system, has better lubricating and improving effects on low-sulfur diesel oil with poor lubricating property than an acid type antiwear agent under the same dosage, and has smaller required dosage and better economy. However, such ester-type antiwear agents are generally produced by esterification of Free Fatty Acids (FFAs) with alcohols such as methanol, and water is inevitably produced as a by-product during the reaction. In the traditional homogeneous acid catalytic system, water is easy to accumulate near the active site of the catalyst, and the reverse hydrolysis reaction of the generated Fatty Acid Methyl Ester (FAME) is promoted to be converted into FFAs again, so that the forward conversion rate and the yield of the esterification reaction are reduced, in the alkali catalytic system, the water and the FFAs are saponified to generate soap, so that raw materials are consumed, the yield of target ester is reduced, and a series of separation and refining problems such as emulsification, layering difficulty and the like are caused. Therefore, it is necessary to provide an acid ester composite type diesel antiwear agent and a preparation method thereof, so as to solve the problems existing in the prior art. Disclosure of Invention In view of the above, the invention provides an acid ester composite type diesel antiwear agent and a preparation method thereof, which can improve the lubricity and antiwear performance of low-sulfur diesel under a lower dosage, and have low corrosiveness and good oxidation stability. In order to achieve the aim, the invention provides a preparation method of an acid ester composite type die