Diesel additive and preparation method thereof

Abstract

The invention relates to the technical field of diesel additives, and discloses a diesel additive and a preparation method thereof, the diesel additive comprises the following raw materials by mass: 15-20 parts of tert-butyl peroxybenzoate, 10-15 parts of polyether amine, 25-30 parts of isooctyl nitrate, 2-4 parts of an antioxidant, 3-5 parts of a preservative, 6-8 parts of a dispersant, and 6-8 parts of a composite antiwear agent. The composite anti-wear agent is added into a mixture of tert-butyl peroxybenzoate, polyether amine and isooctyl nitrate to serve as a diesel oil additive, a polyether amine chain segment on the surface of the composite anti-wear agent and the diesel oil additive can form a steric hindrance or electrostatic stable system, agglomeration of the composite anti-wear agent is prevented, and the combustion performance of diesel oil is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of diesel additives, and specifically relates to a diesel additive and a preparation method thereof. Background Art

[0002] Due to the characteristics of rich oxygen and uneven combustion of diesel in the combustion chamber of a diesel engine, the main pollutants in its exhaust gas are nitrogen oxides and PM particulate matters. In order to reduce the generation of particulate matter PM and improve the combustion efficiency of diesel, adding a diesel additive to diesel can improve the quality of diesel, promote diesel combustion, and thus improve the fuel economy and reduce the generation of particulate matter. Among them, the diesel additive is composed of oxygen-containing organic matter, nano materials, cleaning and activation factors, antioxidants, and preservative materials, which are developed for harmful components such as sulfur, gum, and engine carbon deposits in oil products, and can improve the cetane number, enhance power, and promote the performance of combustion work.

[0003] As a component of diesel additives, metal nanoparticles have small size effect, quantum effect, surface effect, and interface effect, which can improve the oil quality, promote diesel combustion, improve the combustion efficiency and atomization quality, and reduce emissions such as carbon monoxide and nitrogen oxides. However, metal nanoparticles are prone to problems such as agglomeration, which affect the combustion performance of diesel. Moreover, the current diesel has a low sulfur content, resulting in poor lubrication performance, which is prone to problems such as nozzle blockage and sticking wear of fuel injection pumps, affecting the combustion performance of diesel. Summary of the Invention

[0004] The present invention provides a diesel additive and a preparation method thereof, which solve the problems of poor lubrication performance of diesel and incomplete combustion prone to carbon deposition.

[0005] The technical solution of the present invention: A diesel additive, comprising the following raw materials in parts by mass: 15-20 parts of tert-butyl peroxybenzoate, 10-15 parts of polyetheramine, 25-30 parts of isooctyl nitrate, 2-4 parts of antioxidant, 3-5 parts of preservative, 6-8 parts of dispersant, and 6-8 parts of compound anti-wear agent; The compound anti-wear agent is obtained by mixing and reacting pretreated graphene oxide nanosheets, polyetheramine, isocyanate, and tert-butylhydroquinone, and then mixing with modified molybdenum disulfide nanosheets; The modified molybdenum disulfide nanosheets are obtained by intercalating molybdenum disulfide nanosheets with an intercalating agent, and then mixing and reacting with cerium nitrate hexahydrate, a dispersant, and ammonia water.

[0006] A preparation method of a diesel additive, comprising the following preparation steps: Mix tert-butyl peroxybenzoate and isooctyl nitrate, stir at 45 - 55 °C for 20 - 30 min, add a dispersant and polyetheramine, introduce nitrogen, mix and ultrasonicate at 20 - 30 KHz for 10 - 15 min, let stand at 2 - 3 MPa and 65 - 75 °C for 45 - 55 min, add an antioxidant, a preservative and a compound anti-wear agent, continue to stir and mix for 20 - 30 min, cool to room temperature to obtain a diesel additive.

[0007] Further, the dispersant is composed of octadecanamide and polyethylene glycol - 200 mixed in a mass ratio of (1 - 1.2):1.

[0008] Further, the antioxidant is zinc dialkyldithiophosphate.

[0009] Further, the preservative is selected from diisooctylamine or octylbutyldiphenylamine.

[0010] Further, the compound anti-wear agent is specifically prepared by the following steps: A1. Add molybdenum disulfide nanosheets and an intercalating agent to n-hexane, stir evenly, heat to 75 - 85 °C, stir for 3 - 5 h, filter, wash, dry to obtain a solid, add the solid to deionized water, ultrasonicate at 40 - 60 KHz for 1 - 2 h, centrifuge, wash, dry to obtain exfoliated molybdenum disulfide nanosheets; A2. Add the exfoliated molybdenum disulfide nanosheets and cerium nitrate hexahydrate to deionized water, stir evenly, add ammonia water to adjust the pH to 9 - 11, then add ethylene glycol, stir at 200 - 300 r / min for 1 - 2 h, let stand, filter, wash, dry, calcine at 280 - 320 °C for 3 - 5 h, cool to room temperature to obtain modified molybdenum disulfide nanosheets; A3. Add polyetheramine and tert-butylhydroquinone to tetrahydrofuran, stir until completely dissolved, maintain the temperature at 0 - 4 °C, add isocyanate, stir and react for 30 - 35 min, heat to 55 - 65 °C, add pretreated graphene oxide nanosheets, continue to stir and react for 5 - 6 h, cool to room temperature, centrifuge, wash, dry to obtain modified graphene oxide nanosheets; A4. Add the modified graphene oxide nanosheets and the modified molybdenum disulfide nanosheets to ethanol, stir at 60 - 70 °C for 1 - 2 h, let stand, filter, wash, dry to obtain a compound anti-wear agent.

[0011] Further, during the A1 reaction process, the intercalating agent can intercalate into the interlayer of molybdenum disulfide nanosheets. After ultrasonic treatment, exfoliated molybdenum disulfide nanosheets are formed, avoiding the weak van der Waals force between adjacent sulfur atom layers of molybdenum disulfide nanosheets. It is easy for layers to separate, which affects the anti-wear performance of diesel, and further reduces the combustion performance, resulting in the generation of carbon deposits.

[0012] Furthermore, during the above A2 reaction process, the hydroxyl groups on the surface of the exfoliated molybdenum disulfide nanosheets can combine with cerium ions in cerium nitrate hexahydrate. Ammonia water is used as a precipitating agent, and ethylene glycol is used as a dispersant, which can form a complex on the surface of the exfoliated molybdenum disulfide nanosheets. After high-temperature calcination, the complex decomposes by heating, realizing the formation of cerium oxide nanoparticles with a size of 2-5 nm on the surface of the exfoliated molybdenum disulfide nanosheets, and obtaining modified exfoliated molybdenum disulfide nanosheets.

[0013] Furthermore, during the above A3 reaction process, in the organic solvent tetrahydrofuran, the amino group of polyetheramine can react with toluene diisocyanate, and toluene diisocyanate can also react with the hydroxyl group of 2,5-di-tert-butylhydroquinone to form an anti-coking agent; the formed anti-coking agent can adhere to the surface of the pretreated graphene oxide nanosheets, obtaining modified graphene oxide nanosheets.

[0014] Furthermore, during the above A4 reaction process, the amino, ester, and hydroxyl groups on the surface of the modified graphene oxide nanosheets can be chemically bonded with the hydroxyl groups on the surface of the modified exfoliated molybdenum disulfide nanosheets, enabling the modified graphene oxide nanosheets to be coated on the modified exfoliated molybdenum disulfide nanosheets to form a layered composite material as a composite anti-wear agent.

[0015] Furthermore, in step A1, the dosage ratio of the molybdenum disulfide nanosheets, intercalating agent, and n-hexane is (1-2) g : (1-1.2) g : (35-45) mL.

[0016] Furthermore, in step A1, the dosage ratio of the solid and deionized water is (1-3) g : (90-110) mL.

[0017] Furthermore, in step A2, the dosage ratio of the exfoliated molybdenum disulfide nanosheets, cerium nitrate hexahydrate, deionized water, and ethylene glycol is (2-3) g : (8.2-8.4) g : (65-75) mL : (0.6-1) g.

[0018] Furthermore, in step A3, the dosage ratio of the polyetheramine, tert-butylhydroquinone, tetrahydrofuran, isocyanate, and pretreated graphene oxide nanosheets is (7-9) g : (3.1-3.5) g : (45-55) mL : (3-4) g : (5-6) g.

[0019] Furthermore, in step A4, the dosage ratio of the modified graphene oxide nanosheets, modified molybdenum disulfide nanosheets, and ethanol is (1-2) g : (1-1.2) g : (90-110) mL.

[0020] Furthermore, the isocyanate is toluene-2,4-diisocyanate.

[0021] Further, the diameter of the molybdenum disulfide nanosheets is 100 - 130 nm, and the thickness is 5 - 7 nm.

[0022] Further, the intercalating agent is n-butyllithium.

[0023] Further, the pretreatment of graphene oxide nanosheets is specifically prepared by the following steps: Add the graphene oxide nanosheets into the Tris-HCl buffer solution, stir evenly, add dopamine, continue to stir, then filter, wash, and dry to obtain the pretreated graphene oxide nanosheets.

[0024] Further, during the above reaction process, in the Tris-HCl buffer solution, dopamine can self-polymerize on the surface of the graphene oxide nanosheets to form polydopamine, forming polydopamine-modified graphene oxide nanosheets.

[0025] Further, the dosage ratio of graphene oxide nanosheets, Tris-HCl buffer solution, and dopamine is (1 - 2) g : (90 - 110) mL : (0.4 - 0.6) g.

[0026] Further, the graphene oxide nanosheets are monolayer graphene oxide nanosheets, with a diameter of 100 - 150 nm and a thickness of 0.8 - 1.2 nm.

[0027] The present invention has the following beneficial effects: (1) In the technical solution of the present invention, the intercalating agent can intercalate into the interlayer of the molybdenum disulfide nanosheets. After ultrasonic treatment, exfoliated molybdenum disulfide nanosheets are formed, avoiding the weak van der Waals force between adjacent sulfur atom layers of the molybdenum disulfide nanosheets, where the layers are easily separated, affecting the anti-wear performance of diesel and further reducing the combustion performance. Moreover, it is beneficial to synthesize nano-ceria on the exfoliated molybdenum disulfide nanosheets, making it easier to form a layered composite material, improving the anti-wear performance and the combustion performance of diesel; nano-ceria is formed on the surface of the exfoliated molybdenum disulfide nanosheets. On the one hand, the synthesized nano-ceria, as a diesel additive, can promote diesel combustion, enhance the mixing of oil mist and air, make the combustion more complete, and promote the complete combustion of unburned hydrocarbons. On the other hand, the exfoliated molybdenum disulfide nanosheets serve as a carrier for nano-ceria, preventing the agglomeration of small-sized nano-ceria in diesel and affecting the combustion performance of diesel. In addition, nano-ceria forms a concave-convex structure on the exfoliated molybdenum disulfide nanosheets, forming a lubricating film on the metal surface, reducing the frictional loss of the engine, improving the anti-wear property, and increasing the combustion performance of diesel.

[0028] (2) In the technical solution of the present invention, dopamine can self-polymerize on the surface of graphene oxide nanosheets to form polydopamine, forming polydopamine-modified graphene oxide nanosheets, which is beneficial to synthesize anti-carbon deposition agents on the surface of graphene oxide nanosheets, improve the anti-carbon deposition property of diesel, and further improve the combustion performance of diesel. The anti-carbon deposition agent formed by polyetheramine, isocyanate and tert-butylhydroquinone adheres to the surface of pretreated graphene oxide nanosheets. On the one hand, the amine group, ether bond and hydroxyl group contained in the formed anti-carbon deposition agent can adsorb carbon deposition particles through polar interaction, form micelle encapsulation, prevent soot agglomeration and deposition, improve the anti-carbon deposition property of diesel, and further improve the combustion efficiency of diesel. On the other hand, forming an anti-carbon deposition agent on the pretreated graphene oxide nanosheets further improves the high-temperature resistance of the anti-carbon deposition agent, and the anti-carbon deposition agent improves the dispersion performance of the pretreated graphene oxide nanosheets in diesel. As a diesel additive, it improves the anti-carbon deposition and anti-wear properties of diesel.

[0029] (3) In the technical solution of the present invention, the modified graphene oxide nanosheets are coated on the modified exfoliated molybdenum disulfide nanosheets to form a layered composite material. On the one hand, the nano-ceria contained between the layers of the layered composite material acts as a lubricating component, enabling the layers of the layered composite material to move back and forth, producing a micro-ball effect, increasing the buffering distance of the layered composite material, and having excellent anti-wear performance. Moreover, the surface of the layered composite material contains polar functional groups, which can adsorb on the metal surface to form an anti-wear coating, improving the anti-wear property of diesel. On the other hand, the adsorbed carbon deposition particles act between the layers of the layered composite material, together with nano-ceria as a lubricating component, further enhancing the anti-wear property of diesel. And nano-ceria has excellent redox performance, which can promote the oxidation reaction of carbon deposition particles at a lower temperature and be converted into carbon dioxide and water more quickly, thereby reducing the deposition of carbon deposition on the engine surface.

[0030] (4) In the technical solution of the present invention, the composite anti-wear agent is added to the mixture of tert-butyl peroxybenzoate, polyetheramine and isooctyl nitrate as a diesel additive. Among them, the polyetheramine chain segments contained on the surface of the composite anti-wear agent can form a steric hindrance or electrostatic stabilization system with the diesel additive to prevent the aggregation of the composite anti-wear agent and improve the combustion performance of diesel. Specific embodiments

[0031] Next, the technical solutions in the embodiments of the present invention will be described clearly and completely in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0032] The raw materials used in the embodiments of the present invention are as follows, and all the reagents used are of analytical grade.

[0033] Among them, the polyetheramine has a molecular weight of 400 and is purchased from Merck Investment (China) Co., Ltd.

[0034] The preservative is diisooctylamine; the antioxidant is zinc dialkyldithiophosphate.

[0035] Polyethylene glycol - 200 is purchased from Hai'an Petrochemical Factory, Jiangsu Province.

[0036] The isocyanate is toluene - 2,4 - diisocyanate.

[0037] The diameter of the molybdenum disulfide nanosheets is 120 nm and the thickness is 6 nm; the intercalating agent is n - butyllithium.

[0038] The graphene oxide nanosheets are monolayer graphene oxide nanosheets with a diameter of 130 nm and a thickness of 1 nm.

[0039] The pretreated graphene oxide nanosheets are specifically prepared by the following steps: Add 1.5 g of graphene oxide nanosheets to 100 mL of Tris - HCl buffer solution with a pH of 8.5, stir at 25 °C and 2000 r / min for 20 min, add 0.5 g of dopamine, stir at 30 °C and 2000 r / min for 2 h, filter, wash with deionized water 3 times, and dry in an oven at 70 °C for 10 min to obtain the pretreated graphene oxide nanosheets. Example

[0040] A diesel additive, comprising the following raw materials in parts by mass: 15 parts of tert - butyl peroxybenzoate, 10 parts of polyetheramine, 25 parts of isooctyl nitrate, 2 parts of zinc dialkyldithiophosphate, 3 parts of diisooctylamine, 6 parts of dispersant, and 6 parts of compound anti - wear agent; A preparation method of a diesel additive, comprising the following preparation steps: Mix tert - butyl peroxybenzoate and isooctyl nitrate, stir at 45 °C for 20 min, add the dispersant and polyetheramine, introduce nitrogen, mix and ultrasonicate at 20 KHz for 10 min, stand at 2 MPa and 65 °C for 45 min, add zinc dialkyldithiophosphate, diisooctylamine and compound anti - wear agent, continue to stir and mix for 20 min, and cool to room temperature to obtain the diesel additive; Among them, the dispersant is composed of octadecanamide and polyethylene glycol - 200 mixed in a mass ratio of 1:1.

[0041] The compound anti - wear agent is specifically prepared by the following steps: A1. Add 1 g of molybdenum disulfide nanosheets and 1 g of n-butyllithium to 35 mL of n-hexane, stir evenly, heat up to 75 °C, stir for 3 h, filter, wash with deionized water three times, dry in an oven at 70 °C for 10 min to obtain a solid. Add 1 g of the solid to 90 mL of deionized water, ultrasonically treat for 1 h at 40 KHz, centrifuge to collect the product at 6000 r / min, wash the product with deionized water three times, and dry in an oven at 70 °C for 10 min to obtain exfoliated molybdenum disulfide nanosheets; A2. Add 2 g of exfoliated molybdenum disulfide nanosheets and 8.2 g of cerium nitrate hexahydrate to 65 mL of deionized water, stir evenly, add ammonia water to adjust the pH to 9, then add 0.6 g of ethylene glycol, stir at 200 r / min for 1 h, let stand for 1 h, filter, wash with deionized water three times, dry overnight in an oven at 100 °C, place in a muffle furnace, calcine at 280 °C for 3 h, and cool to room temperature to obtain modified molybdenum disulfide nanosheets; A3. Add 7 g of polyetheramine and 3.1 g of tert-butylhydroquinone to 45 mL of tetrahydrofuran, stir until completely dissolved, keep the temperature at 0 °C, add 3 g of toluene-2,4-diisocyanate, stir and react for 30 min, heat up to 55 °C, add 5 g of pretreated graphene oxide nanosheets, continue to stir and react for 5 h, cool to room temperature, centrifuge to collect the solid at 5000 r / min, wash the solid with deionized water three times, and dry in an oven at 80 °C for 10 min to obtain modified graphene oxide nanosheets; A4. Add 1 g of modified graphene oxide nanosheets and 1 g of modified molybdenum disulfide nanosheets to 90 mL of ethanol, stir at 60 °C for 1 h, let stand for 1 h, filter, wash with deionized water three times, and dry in an oven at 70 °C for 10 min to obtain a composite antiwear agent. Example

[0042] A diesel additive comprising the following raw materials in parts by mass: 18 parts of tert-butyl perbenzoate, 13 parts of polyetheramine, 28 parts of isooctyl nitrate, 3 parts of zinc dialkyldithiophosphate, 4 parts of diisooctylamine, 7 parts of dispersant, and 7 parts of composite antiwear agent; A preparation method of a diesel additive, comprising the following preparation steps: Mix tert-butyl perbenzoate and isooctyl nitrate, stir at 50 °C for 25 min, add the dispersant and polyetheramine, introduce nitrogen, mix and ultrasonically treat at 25 KHz for 13 min, let stand at 2.5 MPa and 70 °C for 50 min, add zinc dialkyldithiophosphate, diisooctylamine and the composite antiwear agent, continue to stir and mix for 25 min, and cool to room temperature to obtain the diesel additive; Among them, the dispersant is composed of octadecanamide and polyethylene glycol-200 mixed in a mass ratio of 1.1:1.

[0043] The composite anti-wear agent is specifically prepared by the following steps: A1. Add 1.5 g of molybdenum disulfide nanosheets and 1.1 g of n-butyllithium to 40 mL of n-hexane, stir evenly, heat up to 80 °C, stir for 4 h, filter, wash with deionized water 3 times, dry in an oven at 70 °C for 10 min to obtain a solid. Add 2 g of the solid to 100 mL of deionized water, ultrasonically treat at 50 KHz for 1.5 h, centrifuge to collect the product at 6000 r / min, wash the product with deionized water 3 times, and dry in an oven at 70 °C for 10 min to obtain exfoliated molybdenum disulfide nanosheets; A2. Add 2.5 g of exfoliated molybdenum disulfide nanosheets and 8.3 g of cerium nitrate hexahydrate to 70 mL of deionized water, stir evenly, add ammonia water to adjust the pH to 10, then add 0.8 g of ethylene glycol, stir at 250 r / min for 1.5 h, let stand for 1 h, filter, wash with deionized water 3 times, dry in an oven at 100 °C overnight, place in a muffle furnace, calcine at 300 °C for 4 h, and cool to room temperature to obtain modified molybdenum disulfide nanosheets; A3. Add 8 g of polyetheramine and 3.3 g of tert-butylhydroquinone to 50 mL of tetrahydrofuran, stir until completely dissolved, keep the temperature at 2 °C, add 3.5 g of toluene-2,4-diisocyanate, stir and react for 33 min, heat up to 60 °C, add 5.5 g of pretreated graphene oxide nanosheets, continue to stir and react for 5.5 h, cool to room temperature, centrifuge to collect the solid at 5000 r / min, wash the solid with deionized water 3 times, and dry in an oven at 80 °C for 10 min to obtain modified graphene oxide nanosheets; A4. Add 1.5 g of modified graphene oxide nanosheets and 1.1 g of modified molybdenum disulfide nanosheets to 100 mL of ethanol, stir at 65 °C for 1.5 h, let stand for 1 h, then filter, wash with deionized water 3 times, and dry in an oven at 70 °C for 10 min to obtain the composite anti-wear agent. Example

[0044] A diesel additive comprises the following raw materials in parts by mass: 20 parts of tert-butyl perbenzoate, 15 parts of polyetheramine, 30 parts of isooctyl nitrate, 4 parts of zinc dialkyldithiophosphate, 5 parts of diisooctylamine, 8 parts of dispersant, and 8 parts of composite anti-wear agent; A preparation method of a diesel additive comprises the following preparation steps: Mix tert-butyl perbenzoate and isooctyl nitrate, stir at 55 °C for 30 min, add the dispersant and polyetheramine, introduce nitrogen, mix and ultrasonically treat at 30 KHz for 15 min, let stand at 3 MPa and 75 °C for 55 min, add zinc dialkyldithiophosphate, diisooctylamine and the composite anti-wear agent, continue to stir and mix for 30 min, and cool to room temperature to obtain the diesel additive; Among them, the dispersant is composed of octadecanamide and polyethylene glycol - 200 mixed in a mass ratio of 1.2:1.

[0045] The composite anti - wear agent is specifically prepared by the following steps: A1. Add 2 g of molybdenum disulfide nanosheets and 1.2 g of n - butyllithium to 45 mL of n - hexane, stir evenly, heat up to 85 °C, stir for 5 h, filter, wash with deionized water 3 times, dry in an oven at 70 °C for 10 min to obtain a solid. Add 3 g of the solid to 110 mL of deionized water, ultrasonically treat at 60 KHz for 2 h, centrifuge to collect the product at 6000 r / min, wash the product with deionized water 3 times, and dry in an oven at 70 °C for 10 min to obtain exfoliated molybdenum disulfide nanosheets; A2. Add 3 g of exfoliated molybdenum disulfide nanosheets and 8.4 g of cerium nitrate hexahydrate to 75 mL of deionized water, stir evenly, add ammonia water to adjust the pH to 11, then add 1 g of ethylene glycol, stir at 300 r / min for 2 h, let stand for 1 h, filter, wash with deionized water 3 times, dry in an oven at 100 °C overnight, place in a muffle furnace, calcine at 320 °C for 5 h, cool to room temperature to obtain modified molybdenum disulfide nanosheets; A3. Add 9 g of polyetheramine and 3.5 g of tert - butylhydroquinone to 55 mL of tetrahydrofuran, stir until completely dissolved, keep the temperature at 4 °C, add 4 g of toluene - 2,4 - diisocyanate, stir and react for 35 min, heat up to 65 °C, add 6 g of pretreated graphene oxide nanosheets, continue to stir and react for 6 h, cool to room temperature, centrifuge to collect the solid at 5000 r / min, wash the solid with deionized water 3 times, and dry in an oven at 80 °C for 10 min to obtain modified graphene oxide nanosheets; A4. Add 2 g of modified graphene oxide nanosheets and 1.2 g of modified molybdenum disulfide nanosheets to 110 mL of ethanol, stir at 70 °C for 2 h, let stand for 1 h, then filter, wash with deionized water 3 times, and dry in an oven at 70 °C for 10 min to obtain the composite anti - wear agent.

[0046] Comparative Example 1 A diesel additive comprises the following raw materials in parts by mass: 20 parts of tert - butyl perbenzoate, 15 parts of polyetheramine, 30 parts of isooctyl nitrate, 4 parts of zinc dialkyldithiophosphate, 5 parts of diisooctylamine, 8 parts of dispersant, and 8 parts of composite anti - wear agent; A preparation method of a diesel additive comprises the following preparation steps: Mix tert-butyl peroxybenzoate and isooctyl nitrate, stir for 30 min at 55 °C, add a dispersant and polyetheramine, introduce nitrogen, mix and ultrasonicate at 30 KHz for 15 min, stand at 3 MPa and 75 °C for 55 min, add zinc dialkyldithiophosphate, diisooctylamine and a composite antiwear agent, continue to stir and mix for 30 min, and cool to room temperature to obtain a diesel additive; Among them, the dispersant is composed of octadecanamide and polyethylene glycol-200 mixed in a mass ratio of 1.2:1.

[0047] The composite antiwear agent is specifically prepared by the following steps: A1. Add 3 g of molybdenum disulfide nanosheets and 8.4 g of cerium nitrate hexahydrate to 75 mL of deionized water, stir evenly, add ammonia water to adjust the pH to 11, then add 1 g of ethylene glycol, stir at 300 r / min for 2 h, stand for 1 h, filter, wash with deionized water 3 times, dry overnight in an oven at 100 °C, place in a muffle furnace, calcine at 320 °C for 5 h, and cool to room temperature to obtain modified molybdenum disulfide nanosheets; A2. Add 9 g of polyetheramine and 3.5 g of tert-butylhydroquinone to 55 mL of tetrahydrofuran, stir until completely dissolved, keep the temperature at 4 °C, add 4 g of toluene-2,4-diisocyanate, stir and react for 35 min, raise the temperature to 65 °C, add 6 g of pretreated graphene oxide nanosheets, continue to stir and react for 6 h, cool to room temperature, centrifuge and collect the solid at 5000 r / min, wash the solid with deionized water 3 times, and dry in an oven at 80 °C for 10 min to obtain modified graphene oxide nanosheets; A3. Add 2 g of modified graphene oxide nanosheets and 1.2 g of modified molybdenum disulfide nanosheets to 110 mL of ethanol, stir at 70 °C for 2 h, stand for 1 h, then filter, wash with deionized water 3 times, and dry in an oven at 70 °C for 10 min to obtain the composite antiwear agent.

[0048] Comparative Example 2 A diesel additive includes the following raw materials in parts by mass: 20 parts of tert-butyl peroxybenzoate, 15 parts of polyetheramine, 30 parts of isooctyl nitrate, 4 parts of zinc dialkyldithiophosphate, 5 parts of diisooctylamine, 8 parts of a dispersant, and 8 parts of a composite antiwear agent; A preparation method of a diesel additive includes the following preparation steps: Mix tert-butyl peroxybenzoate and isooctyl nitrate, stir for 30 min at 55 °C, add a dispersant and polyetheramine, introduce nitrogen, mix and ultrasonicate at 30 KHz for 15 min, stand at 3 MPa and 75 °C for 55 min, add zinc dialkyldithiophosphate, diisooctylamine and a composite antiwear agent, continue to stir and mix for 30 min, and cool to room temperature to obtain a diesel additive; Among them, the dispersant is formed by mixing octadecanamide and polyethylene glycol - 200 in a mass ratio of 1.2:1.

[0049] The composite anti - wear agent is specifically prepared by the following steps: A1. Add 2 g of molybdenum disulfide nanosheets and 1.2 g of n - butyllithium to 45 mL of n - hexane, stir evenly, heat up to 85 °C, stir for 5 h, filter, wash with deionized water 3 times, dry in an oven at 70 °C for 10 min to obtain a solid. Add 3 g of the solid to 110 mL of deionized water, ultrasonically treat at 60 KHz for 2 h, centrifuge and collect the product at 6000 r / min, wash the product with deionized water 3 times, and dry in an oven at 70 °C for 10 min to obtain exfoliated molybdenum disulfide nanosheets; A2. Add 9 g of polyetheramine and 3.5 g of tert - butylhydroquinone to 55 mL of tetrahydrofuran, stir until completely dissolved, keep the temperature at 4 °C, add 4 g of toluene - 2,4 - diisocyanate, stir and react for 35 min, heat up to 65 °C, add 6 g of pretreated graphene oxide nanosheets, continue to stir and react for 6 h, cool to room temperature, centrifuge and collect the solid at 5000 r / min, wash the solid with deionized water 3 times, and dry in an oven at 80 °C for 10 min to obtain modified graphene oxide nanosheets; A3. Add 2 g of modified graphene oxide nanosheets and 1.2 g of exfoliated molybdenum disulfide nanosheets to 110 mL of ethanol, stir at 70 °C for 2 h, let stand for 1 h, then filter, wash with deionized water 3 times, and dry in an oven at 70 °C for 10 min to obtain the composite anti - wear agent.

[0050] Comparative Example 3 A diesel additive comprises the following raw materials in parts by mass: 20 parts of tert - butyl peroxybenzoate, 15 parts of polyetheramine, 30 parts of isooctyl nitrate, 4 parts of zinc dialkyldithiophosphate, 5 parts of diisooctylamine, 8 parts of dispersant, and 8 parts of composite anti - wear agent; A preparation method of a diesel additive comprises the following preparation steps: Mix tert - butyl peroxybenzoate and isooctyl nitrate, stir at 55 °C for 30 min, add the dispersant and polyetheramine, introduce nitrogen, ultrasonically mix at 30 KHz for 15 min, let stand at 3 MPa and 75 °C for 55 min, add zinc dialkyldithiophosphate, diisooctylamine and the composite anti - wear agent, continue to stir and mix for 30 min, cool to room temperature to obtain the diesel additive; Among them, the dispersant is formed by mixing octadecanamide and polyethylene glycol - 200 in a mass ratio of 1.2:1.

[0051] The composite anti - wear agent is specifically prepared by the following steps: A1. Add 2 g of molybdenum disulfide nanosheets and 1.2 g of n-butyllithium to 45 mL of n-hexane, stir evenly, heat up to 85 °C, stir for 5 h, filter, wash with deionized water 3 times, dry in an oven at 70 °C for 10 min to obtain a solid. Add 3 g of the solid to 110 mL of deionized water, ultrasonically treat at 60 KHz for 2 h, centrifuge and collect the product at 6000 r / min, wash the product with deionized water 3 times, and dry in an oven at 70 °C for 10 min to obtain exfoliated molybdenum disulfide nanosheets; A2. Add 3 g of exfoliated molybdenum disulfide nanosheets and 8.4 g of cerium nitrate hexahydrate to 75 mL of deionized water, stir evenly, add ammonia water to adjust the pH to 11, then add 1 g of ethylene glycol, stir at 300 r / min for 2 h, let stand for 1 h, filter, wash with deionized water 3 times, dry in an oven at 100 °C overnight, place in a muffle furnace, calcine at 320 °C for 5 h, cool to room temperature to obtain modified molybdenum disulfide nanosheets; A3. Add 9 g of polyetheramine and 3.5 g of tert-butylhydroquinone to 55 mL of tetrahydrofuran, stir until completely dissolved, keep the temperature at 4 °C, add 4 g of toluene-2,4-diisocyanate, stir and react for 35 min, heat up to 65 °C, add 6 g of graphene oxide nanosheets, continue to stir and react for 6 h, cool to room temperature, centrifuge and collect the solid at 5000 r / min, wash the solid with deionized water 3 times, and dry in an oven at 80 °C for 10 min to obtain modified graphene oxide nanosheets; A4. Add 2 g of modified graphene oxide nanosheets and 1.2 g of modified molybdenum disulfide nanosheets to 110 mL of ethanol, stir at 70 °C for 2 h, let stand for 1 h, then filter, wash with deionized water 3 times, and dry in an oven at 70 °C for 10 min to obtain a composite antiwear agent.

[0052] Comparative Example 4 A diesel additive comprising the following raw materials in parts by mass: 20 parts of tert-butyl peroxybenzoate, 15 parts of polyetheramine, 30 parts of isooctyl nitrate, 4 parts of zinc dialkyldithiophosphate, 5 parts of diisooctylamine, 8 parts of dispersant, and 8 parts of composite antiwear agent; A preparation method of a diesel additive, comprising the following preparation steps: Mix tert-butyl peroxybenzoate and isooctyl nitrate, stir at 55 °C for 30 min, add the dispersant and polyetheramine, introduce nitrogen, ultrasonically mix at 30 KHz for 15 min, stand at 3 MPa and 75 °C for 55 min, add zinc dialkyldithiophosphate, diisooctylamine and the composite antiwear agent, continue to stir and mix for 30 min, cool to room temperature to obtain the diesel additive; Among them, the dispersant is composed of octadecanamide and polyethylene glycol-200 mixed in a mass ratio of 1.2:1.

[0053] The composite anti-wear agent is specifically prepared by the following steps: A1. Add 2 g of molybdenum disulfide nanosheets and 1.2 g of n-butyllithium to 45 mL of n-hexane, stir evenly, heat up to 85 °C, stir for 5 h, filter, wash with deionized water 3 times, dry in an oven at 70 °C for 10 min to obtain a solid. Add 3 g of the solid to 110 mL of deionized water, ultrasonically treat for 2 h at 60 KHz, centrifuge to collect the product at 6000 r / min, wash the product with deionized water 3 times, and dry in an oven at 70 °C for 10 min to obtain exfoliated molybdenum disulfide nanosheets; A2. Add 3 g of exfoliated molybdenum disulfide nanosheets and 8.4 g of cerium nitrate hexahydrate to 75 mL of deionized water, stir evenly, add ammonia water to adjust the pH to 11, then add 1 g of ethylene glycol, stir at 300 r / min for 2 h, let stand for 1 h, filter, wash with deionized water 3 times, dry overnight in an oven at 100 °C, place in a muffle furnace, calcine at 320 °C for 5 h, and cool to room temperature to obtain modified molybdenum disulfide nanosheets; A3. Add 2 g of pretreated graphene oxide nanosheets and 1.2 g of modified molybdenum disulfide nanosheets to 110 mL of ethanol, stir at 70 °C for 2 h, let stand for 1 h, filter, wash with deionized water 3 times, and dry in an oven at 70 °C for 10 min to obtain the composite anti-wear agent.

[0054] Now, the performance of the diesel additives prepared in Examples 1-3 and Comparative Examples 1-4 is detected.

[0055] Mix the above-prepared diesel additive with No. 0 diesel, and the mass ratio of the diesel additive to No. 0 diesel is 1.5:98.5.

[0056] Diesel combustion calorific value test: The combustion calorific value of No. 0 diesel containing the diesel additive is determined by the low-pressure oxygen bomb combustion method, and the detection is carried out in accordance with the GB384-1981 Petroleum Product Calorific Value Determination Method. The test conditions are as follows: carried out at an altitude of 70 m, and the corresponding oxygen bomb oxygen filling pressure is 0.89 MPa; the combustion calorific value of No. 0 diesel without adding the diesel additive is 27.1 KJ; Lubrication performance detection: The tribological performance of diesel is tested by a high-frequency reciprocating friction and wear tester (highfrequency reciprocatingrig, HFRR), and the test is carried out according to the SHT 0765-200 Diesel Lubrication Evaluation Standard Method. The wear scar size (steel ball wear scar diameter) is measured by a three-dimensional scanner. The test conditions are as follows: four-ball friction and wear tester, load 39.2 N, rotation speed 600 r / min, temperature 25 °C, test time 40 min; the steel ball wear scar diameter of No. 0 diesel without adding the diesel additive is 0.54 mm; Detection of anti-carbon deposition performance: The gum content of No. 0 diesel after adding the diesel additive prepared above was determined by the actual gum method GBT 509-1988. Method: Add 25 mL of No. 0 diesel with the diesel additive into a beaker without a nozzle, place it in an oil bath groove at 250 °C, install a three-way pipe at the center of the bath cover, adjust the three-way pipe so that the lower end of the pipe is 3 cm away from the liquid level of the sample, ventilate the beaker, increase the gas flow rate from 20 L / min to 50 L / min within the first 20 min, keep the ventilation state all the time. When no more oil and gas emerge, there is a dry residue at the bottom of the beaker, and the sample evaporation is complete. Cool for 30 min under dry conditions, then cool and weigh. The gum content produced by No. 0 diesel without adding the diesel additive is 2511 mg / 100 mL.

[0057] The test results are shown in Table 1 below.

[0058] Table 1 Performance detection of diesel additives prepared in Examples 1-3 and Comparative Examples 1-4

[0059] It can be seen from the data in Table 1 that the diesel additives prepared in Examples 1-3 can improve the combustion performance, lubrication performance and anti-carbon deposition performance of diesel.

[0060] In Comparative Example 1, a composite anti-wear agent prepared by replacing exfoliated molybdenum disulfide nanosheets with molybdenum disulfide nanosheets was added to the diesel additive and then mixed with diesel. Its combustion, anti-wear and anti-carbon deposition performance decreased, which proved that the intercalating agent intercalated into the interlayer of molybdenum disulfide nanosheets to form exfoliated molybdenum disulfide nanosheets, avoiding the weak van der Waals force between adjacent sulfur atom layers of molybdenum disulfide nanosheets, and it was easy to separate between layers, affecting the anti-wear performance of diesel, and then reducing the combustion performance. Moreover, the exfoliated molybdenum disulfide nanosheets were beneficial to synthesize nano-ceria on the exfoliated molybdenum disulfide nanosheets, and it was easier to form a layered composite material, improving the anti-wear performance and the combustion performance of diesel.

[0061] In Comparative Example 2, a composite anti-wear agent prepared by replacing modified molybdenum disulfide nanosheets with exfoliated molybdenum disulfide nanosheets was added to the diesel additive and then mixed with diesel. Its combustion, anti-wear and anti-carbon deposition performance decreased, which proved that synthesizing nano-ceria on the exfoliated molybdenum disulfide nanosheets could promote diesel combustion, and the exfoliated molybdenum disulfide nanosheets served as the carrier of nano-ceria, avoiding the aggregation of small-sized nano-ceria in diesel. In addition, nano-ceria formed a concave-convex structure on the exfoliated molybdenum disulfide nanosheets, forming a lubricating film on the metal surface, reducing the friction loss of the engine, improving the anti-wear property and increasing the combustion performance of diesel.

[0062] Comparative Example 3 The composite anti-wear agent prepared by replacing the pretreated graphene oxide nanosheets with graphene oxide nanosheets was added to the diesel additive and then mixed with diesel. Its combustion, anti-wear, and anti-carbon deposition performances decreased, which proved that polydopamine was self-polymerized on the surface of graphene oxide nanosheets to form pretreated graphene oxide nanosheets. The polar functional groups on the surface were beneficial to the synthesis of the anti-carbon deposition agent on the surface of graphene oxide nanosheets, improving the anti-carbon deposition property of diesel, enhancing the combustion performance of diesel, and improving the dispersion performance of pretreated graphene oxide nanosheets in diesel. As a diesel additive, it improved the anti-carbon deposition and anti-wear performances of diesel.

[0063] Comparative Example 4 The composite anti-wear agent prepared by replacing the modified graphene oxide nanosheets with pretreated graphene oxide nanosheets was added to the diesel additive and mixed with diesel. Its combustion, anti-wear, and anti-carbon deposition performances decreased, which proved that the anti-carbon deposition agent formed by polyetheramine, isocyanate, and tert-butylhydroquinone adhered to the surface of pretreated graphene oxide nanosheets. The amine groups, ether bonds, and hydroxyl groups contained in the formed anti-carbon deposition agent could adsorb carbon deposition particles through polar interactions, improving the anti-carbon deposition performance of diesel. Moreover, the adsorbed carbon deposition particles acted between the layers of the layered composite material. Together with nano-ceria as a lubricating component, it further enhanced the anti-wear performance of diesel.

[0064] In the description of the specification, the description referring to terms such as "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0065] The above content is only an example and illustration of the present invention. Those skilled in the art of this technology can make various modifications or supplements to the described specific embodiments or use similar ways to replace them. As long as they do not deviate from the scope defined by the invention, they should fall within the protection scope of the present invention.

Claims

1. A diesel additive, characterized in that: The method comprises the following raw materials in parts by weight: 15-20 parts of tert-butyl perbenzoate, 10-15 parts of polyetheramine, 25-30 parts of isooctyl nitrate, 2-4 parts of antioxidant, 3-5 parts of preservative, 6-8 parts of dispersant and 6-8 parts of composite anti-wear agent; The composite anti-wear agent is obtained by mixing pretreated graphene oxide nanosheets, polyetheramine, isocyanate and tert-butyl hydroquinone, and then mixing with modified molybdenum disulfide nanosheets; The modified molybdenum disulfide nanosheet is obtained by subjecting the molybdenum disulfide nanosheet to intercalation treatment with an intercalation agent and then reacting the intercalation agent with cerium nitrate hexahydrate, ethylene glycol and ammonia water.

2. A diesel additive according to claim 1, characterized in that: The composite antiwear agent is specifically prepared by the following steps: A1. Adding molybdenum disulfide nanosheets and intercalation agents to n-hexane, stirring evenly, heating to 75-85°C, stirring for 3-5h, filtering, washing, and drying to obtain a solid, adding the solid to deionized water, ultrasonically treating at 40-60KHz for 1-2h, centrifuging, washing, and drying to obtain exfoliated molybdenum disulfide nanosheets; A2. The exfoliated molybdenum disulfide nanosheets and cerium nitrate hexahydrate were added to deionized water, stirred evenly, ammonia was added to adjust the pH to 9-11, and ethylene glycol was added, stirred at 200-300r / min for 1-2h, allowed to stand, filtered, washed, dried, calcined at 280-320°C for 3-5h, and cooled to room temperature to obtain modified molybdenum disulfide nanosheets; A3. Add polyetheramine and tert-butylhydroquinone to tetrahydrofuran, stir until completely dissolved, maintain the temperature at 0-4°C, add isocyanate, stir and react for 30-35 minutes, raise the temperature to 55-65°C, add pretreated graphene oxide nanosheets, continue stirring and reacting for 5-6 hours, cool to room temperature, centrifuge, wash, and dry to obtain modified graphene oxide nanosheets; A4. Add modified graphene oxide nanosheets and modified molybdenum disulfide nanosheets into ethanol, stir at 60-70° C. for 1-2 hours, let stand, filter, wash and dry to obtain a composite anti-wear agent.

3. A diesel additive according to claim 2, characterized in that: In step A1, the molybdenum disulfide nanosheets, intercalation agent and n-hexane are used in a ratio of (1-2) g: (1-1.2) g: (35-45) mL; The ratio of the solid to deionized water is (1-3) g: (90-110) mL.

4. A diesel additive according to claim 2, characterized in that: In step A2, the ratio of the exfoliated molybdenum disulfide nanosheets, cerium nitrate hexahydrate, deionized water and ethylene glycol is (2-3) g: (8.2-8.4) g: (65-75) mL: (0.6-1) g.

5. A diesel additive according to claim 2, characterized in that: In step A3, the amount ratio of the polyetheramine, tert-butylhydroquinone, tetrahydrofuran, isocyanate and pretreated graphene oxide nanosheets is (7-9) g: (3.1-3.5) g: (45-55) mL: (3-4) g: (5-6) g.

6. A diesel additive according to claim 2, characterized in that: In step A4, the ratio of the modified graphene oxide nanosheets, the modified molybdenum disulfide nanosheets and ethanol is (1-2) g: (1-1.2) g: (90-110) mL.

7. A diesel additive according to claim 1, characterized in that: The pretreated graphene oxide nanosheets are specifically prepared by the following steps: The graphene oxide nanosheets are added into Tris-HCl buffer, stirred evenly, dopamine is added, and stirring is continued, and then filtered, washed, and dried to obtain pretreated graphene oxide nanosheets.

8. A diesel additive according to claim 7, characterized in that: The amount ratio of the graphene oxide nanosheets, Tris-HCl buffer and dopamine is (1-2) g: (90-110) mL: (0.4-0.6) g.

9. A method for preparing the diesel additive according to any one of claims 1 to 8, characterized in that: The method comprises the following preparation steps: The tert-butyl perbenzoate and isooctyl nitrate are mixed, stirred at 45-55° C. for 20-30 min, a dispersant and a polyetheramine are added, nitrogen is introduced, ultrasonic mixing is performed at 20-30 KHz for 10-15 min, the mixture is allowed to stand at 2-3 MPa and 65-75° C. for 45-55 min, an antioxidant, a preservative and a composite anti-wear agent are added, the mixture is stirred and mixed for 20-30 min, and the mixture is cooled to room temperature to obtain a diesel additive.

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