High-energy cleaning type composite solid fuel additive and preparation method thereof

Abstract

The present application relates to the technical field of fuel additive, in particular to a high-energy cleaning type composite solid fuel additive and a preparation method thereof. The additive comprises the following raw materials: myristic acid, stearic acid, a composite catalytic unit, modified soybean lecithin, tributyl borate, butylated hydroxyanisole and polyethylene glycol monostearate. The composite catalytic unit is prepared by coordination of diethyl phosphinic acid with manganese chloride, lanthanum chloride and cerium chloride; the modified soybean lecithin is obtained by ammonolysis and intramolecular lactonization and contains a five-membered cyclic phosphonate structure. During preparation, the components are dispersed by ultrasonic dispersion after being loaded on a melting carrier, and then solidified and formed. The additive realizes cleaning and repair integration through double-metal synergistic catalysis and combustion strengthening, and the composite carrier can controllably release and adapt to all working conditions. The product is soft and easy to discharge, has high economic efficiency and environmental compatibility, and is convenient to store and use.

Description

Technical Field

[0001] This invention relates to the field of fuel additive technology, and in particular to a high-energy, clean composite solid fuel additive and its preparation method. Background Technology

[0002] As the automotive industry moves towards higher compression ratios and higher power densities, and global environmental regulations become increasingly stringent in restricting exhaust emissions, fuel additives, as core aids for improving fuel quality and optimizing engine performance, face continuously evolving demands for functional integration and environmental compatibility. While commercially available solid fuel additives have achieved basic functions such as combustion improvement and cleaning, significant technical bottlenecks remain in areas such as catalytic efficiency, repair capabilities, carrier compatibility, and long-term stability, making it difficult to meet the comprehensive performance requirements under complex operating conditions.

[0003] In existing solid fuel additives, the catalytic combustion-enhancing components mostly rely on traditional materials such as ferrocene and monometallic carboxylates. The core issue lies in the imbalance between activity and safety. Taking the most widely used ferrocene as an example, although it can improve combustion through Fe... 2+ While the redox cycle shortens the fuel ignition delay, it has three major drawbacks: First, the combustion products are hard Fe2O3 particles, which, with long-term use, will exacerbate the wear of cylinders and piston rings, and even clog the three-way catalytic converter and particulate filter, leading to the failure of the engine aftertreatment system; second, the catalytic spectrum of the single-metal active center is narrow, which can only accelerate the alkane chain-initiated reaction and has a weak ability to oxidize carbon soot precursors (such as polycyclic aromatic hydrocarbons), resulting in limited smoke reduction and fuel saving effects; third, it has insufficient thermal stability and is prone to decomposition at high temperatures in the engine combustion chamber, causing the catalytic activity to decay rapidly over time.

[0004] Some alternatives use molybdenum-based or rare-earth monometallic catalysts, which can improve wear issues. However, molybdenum-based catalysts are expensive and have poor biodegradability. Rare-earth monometallic catalysts have weak oxygen vacancy regulation capabilities, requiring high addition amounts to achieve the same catalytic effect, further increasing production costs and the risk of particulate emissions.

[0005] In existing technologies, the carbon deposit cleaning and wear repair functions of fuel additives mostly rely on the physical mixing of independent components, lacking molecular-level synergistic design, resulting in poor functional complementarity and strong application limitations. The cleaning components are mainly polyisobutylene amine (PEA) and polyether amine (PIBA), which can adsorb and disperse carbon deposits through polar groups, but they have no lubrication and repair capabilities themselves, and are prone to pyrolysis at high temperatures, forming new deposit precursors instead. The repair components are mainly organic molybdenum and zinc dialkyl dithiophosphonate, which achieve anti-wear by forming a sulfide / phosphonate film on the metal surface, but their cleaning and dispersing capabilities are almost zero, and they cannot simultaneously address problems such as injector clogging and valve deposits caused by carbon deposits.

[0006] Natural soybean lecithin, rich in polar groups such as phosphonate groups and hydroxyl groups, is considered a potential integrated cleaning and repairing raw material. However, in the combustion chamber and fuel injector area of ​​an engine, the temperature can reach 300-500℃. The phospholipid skeleton of unmodified soybean lecithin contains a large number of unstable groups such as ester groups and hydroxyl groups. Under such high temperature conditions, it is prone to oxidative degradation or pyrolysis. The ester groups break down to generate free fatty acids and glycerol, and the hydroxyl groups are oxidized to carbonyl groups. These degradation products not only lose their cleaning and repairing activity, but may also further polymerize to form colloidal deposit precursors, which will aggravate problems such as valve deposits and fuel injector blockage, completely contradicting the core requirements of cleaning and carbon reduction. The exposed phosphonate anions in its molecular structure are easy to combine with trace metal cations in fuel to form precipitates, which not only consume the active components, but the precipitates may also adhere to the surfaces of fuel injectors and valves, which will aggravate the risk of carbon deposits.

[0007] The carrier performance of solid fuel additives directly determines the release rhythm and efficiency of functional components. Existing carrier systems generally suffer from poor synergy between dissolution and release. The dissolution rate of early single fatty acid carriers (such as pure stearic acid and pure myristic acid) is greatly affected by temperature: during low-temperature starts, the carrier melts slowly, and the functional components cannot be released in time, resulting in incomplete combustion of fuel and insufficient power during the cold start phase; during high-temperature and high-load operation, the carrier disintegrates rapidly, and the instantaneous concentration of catalytic and cleaning components is too high, which not only wastes active components but may also produce gum deposits due to excessive local reactions. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the existing technology and to propose a high-energy clean composite solid fuel additive and its preparation method.

[0009] To achieve the above objectives, this invention provides a high-energy clean composite solid fuel additive, comprising the following raw materials in parts by weight: myristic acid: 65-75 parts, stearic acid: 10-15 parts, composite catalytic unit: 0.075-0.125 parts, modified soybean lecithin: 0.4-0.6 parts, tributyl borate: 0.1-0.2 parts, butylated hydroxyanisole: 0.03-0.08 parts, and polyethylene glycol monostearate: 0.15-0.25 parts;

[0010] The preparation method of the composite catalytic unit is as follows:

[0011] (1) Add diethylphosphonic acid to ethanol, stir for 10-20 min, add triethylamine, adjust the pH of the system to 7-8, and obtain a phosphonate solution; the hydroxyl group of diethylphosphonic acid releases a proton, the nitrogen atom of triethylamine accepts a proton, forming a triethylamine cation, and at the same time, the phosphonic acid molecule is converted into a phosphonate anion;

[0012] (2) Add manganese chloride, lanthanum chloride and cerium chloride to deionized water and stir for 10-20 min to obtain a mixed metal salt solution;

[0013] (3) The mixed metal salt solution is added dropwise to the hypophosphite solution. After the addition is complete, the temperature is raised to 40-60℃ and the reaction is stirred at a constant temperature for 3-5 hours. The precipitate is collected by suction filtration, washed, and dried to obtain the composite catalytic unit. The hypophosphite anion acts as a multidentate ligand and coordinates with Mn through a coordinate bond. 2+ La 3+ Ce 3+ They combine to form stable coordination compounds. The resulting coordination compounds have low solubility in the ethanol / water mixture and precipitate out as solid precipitates. They can be separated from water-soluble byproducts by suction filtration.

[0014] The modified soybean lecithin is prepared as follows:

[0015] Add soybean lecithin and white oil to the reaction vessel, heat to 70-90℃, stir for 20-40 min, then add ethanol and p-toluenesulfonic acid, stir for 5-15 min, then add diethanolamine, stir and react for 4-6 h, cool to room temperature, remove ethanol by vacuum distillation, add the crude product to petroleum ether, stir for 30-60 min, wash 3 times with deionized water, separate the liquid and take the organic phase, dry with anhydrous sodium sulfate, remove the solvent by vacuum distillation, and obtain modified soybean lecithin;

[0016] Soy lecithin contains phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylglycerol, phosphatidic acid, and other phospholipids, with the following general formula:

[0017] The reaction mechanism in the ammonolysis modification process of soybean lecithin is as follows:

[0018] ;

[0019] In soybean lecithin, the ester group is highly activated under the catalysis of p-toluenesulfonic acid. Diethanolamine reacts with fatty acid esters to form corresponding fatty amides and hydroxyl-containing fatty acid phosphonic acid glycerides. The residual intramolecular hydroxyl groups undergo intramolecular esterification with phosphonate anions in the presence of p-toluenesulfonic acid to form five-membered cyclic phosphonates, which effectively mask the anions in phosphonates, making the molecules less prone to precipitation and failure due to the action of metal ions.

[0020] Preferably, the molecular formula of the polyethylene glycol monostearate is HO(CH2CH2O). n OCC 17 H 35 , where n≈10.

[0021] Preferably, in (1), the weight ratio of diethylphosphonic acid, ethanol and triethylamine is 1:3-5:0.6-0.8.

[0022] Preferably, in (2), the weight ratio of manganese chloride, lanthanum chloride, cerium chloride and deionized water is 5-7:1-3:0.3-0.7:20-40.

[0023] Preferably, the weight ratio of the mixed metal salt solution and the hypophosphite solution in (3) is 1:1.8-2.4.

[0024] Preferably, the dripping rate of the mixed metal salt solution into the hypophosphite solution in step (3) is 2-6 ml / min.

[0025] Preferably, in the preparation method of the composite catalytic unit, soybean lecithin, white oil, ethanol, p-toluenesulfonic acid, diethanolamine and petroleum ether are in a weight ratio of 1:0.3-0.4:0.5-0.7:0.001-0.003:0.1-0.25:2-4.

[0026] Furthermore, the present invention also provides a method for preparing a high-energy clean composite solid fuel additive, comprising the following steps:

[0027] S1. Mix myristic acid and stearic acid, heat to 70-80℃ to melt, and stir for 10-20 minutes to obtain a molten carrier;

[0028] S2. Add the composite catalytic unit to the molten support and stir under ultrasonication for 20-40 min to obtain mixture A;

[0029] S3. Add the modified soybean lecithin and tributyl borate to mixture A, stir for 20-40 minutes to obtain mixture B;

[0030] S4. Add butylated hydroxyanisole and polyethylene glycol monostearate to mixture B, stir for 20-40 min to obtain mixture C;

[0031] S5. Pour mixture C into a round mold, cool it to 40°C and let it stand for 1 hour, then let it cool naturally to room temperature to solidify. After demolding, you will get a high-energy clean composite solid fuel additive.

[0032] Preferably, the ultrasonic frequency in S2 is 40-60kHz.

[0033] Preferably, the single-particle weight of the high-energy cleaning composite solid fuel additive in S5 is 1.5-2.0g. The high-energy cleaning composite solid fuel additive is added directly to the fuel tank before and after refueling, and each particle of the high-energy cleaning composite solid fuel additive can be mixed with 30 liters of gasoline.

[0034] Preferably, the mechanism of action of the high-energy cleaning composite solid fuel additive of the present invention is as follows:

[0035] After entering the fuel system, the composite solid fuel additive first achieves controlled release by relying on the characteristics of the fatty acid solid carrier. Myristic acid (melting point about 52-54℃) and stearic acid (melting point about 67-72℃) constitute the composite carrier. This ratio makes the carrier solid granules at room temperature, which is convenient for storage and quantitative addition. When the granules are added to the fuel, as the fuel temperature rises when the engine starts, the carrier gradually melts and dissolves. Its dissolution rate is positively correlated with the engine operating conditions. It is released slowly at low temperature starts to avoid excessive local reactions caused by a sudden increase in the concentration of functional components. It dissolves faster at high temperature and high load to ensure that a sufficient amount of active components participate in the action. At the same time, polyethylene glycol monostearate acts as a dispersant. The hydrophilic segments in its molecules combine with the polar groups of modified soybean lecithin, and the hydrophobic segments are compatible with the fatty acid carrier and fuel, which uniformly disperses the catalytic unit and the cleaning and repair unit, avoiding agglomeration and precipitation, and laying the physical foundation for the efficient performance of subsequent functions.

[0036] During the fuel combustion stage, the composite catalytic unit enhances combustion efficiency through a bimetallic synergistic catalytic mechanism. In the molecular structure of this composite catalytic unit, Mn... 2+ As a redox active center, it passes through in the early stage of combustion The valence cycle of La transfers electrons to fuel hydrocarbon molecules, lowering the energy barriers for breaking C-C and CH bonds, allowing the fuel to initiate chain reactions at lower temperatures and shortening the ignition delay period. 3+ With Ce 3+ By providing oxygen vacancies, these active oxygen species adsorb and activate oxygen molecules during combustion, rapidly oxidizing precursors of incomplete combustion soot (such as polycyclic aromatic hydrocarbons and alkenes) into CO2 and H2O. Phosphinate ligands not only stabilize bimetallic ions through coordination bonds, but also contribute to the combustion of PO4. 3- When combined with oxides of Mn, La, and Ce, it forms a composite phosphonate product. This composite product has two major advantages: First, the particle size is finer and more dispersed. The small molecule volatiles generated by the combustion of ligands carry the metal oxides to a uniform distribution, which can be quickly discharged with the fuel circulation or combustion airflow. Second, it has low adhesion. The composite phosphonate does not chemically bond with engine metal parts (such as cylinder walls and piston rings). It is easy to peel off under mechanical impact and fuel flushing, avoiding the formation of stubborn deposits or becoming carbon deposit nuclei. Tributyl borate further synergizes in this stage: the B2O3 generated by its combustion can form a eutectic with soot particles, reducing the soot oxidation temperature. Synergistically with bimetallic catalysis, it improves fuel combustion efficiency and reduces carbon monoxide and hydrocarbon emissions.

[0037] For existing carbon deposits and sediments inside the engine, modified soybean lecithin achieves cleaning through a step-by-step process of penetration, dispersion, and stripping. The modified soybean lecithin molecules retain long-chain fatty acid chains (C16-C18) that are lipophilic, allowing them to penetrate into the pores of carbon deposits (mainly hydrocarbon polymers) and bind to the carbon deposit molecules through van der Waals forces, weakening their adhesion to the metal surface. Meanwhile, the highly polar fatty amide groups introduced by the ammonolysis reaction can be adsorbed onto the surface of carbon deposit particles through electrostatic attraction, breaking up the originally agglomerated particles. Carbon deposits disperse into tiny particles and are washed away from metal surfaces (such as fuel injectors and intake valves) by the flow of fuel. More importantly, the five-membered cyclic phosphonate structure formed by intramolecular esterification can form coordination bonds with metal atoms on metal surfaces (such as cylinder walls and piston rings) through phosphorus-oxygen bonds under high temperature and pressure, generating an organic / inorganic composite film with good toughness and wear resistance. It can fill the tiny scratches on the metal surface and reduce the direct friction between the piston and cylinder liner, thereby reducing engine wear and achieving the dual function of cleaning and repair.

[0038] The beneficial effects of this invention are:

[0039] 1. This invention constructs a highly efficient synergistic catalytic system through composite catalytic units, solving the problem of the imbalance between activity and safety in traditional single-metal catalysts. Mn 2+ As a catalytic core, through Valence state cycling rapidly transfers electrons, lowering the bond energy barrier of fuel hydrocarbons and shortening the ignition delay period; La 3+ / Ce 3+ By utilizing oxygen vacancies to activate oxygen molecules, highly active species are generated to oxidize soot precursors and incomplete combustion products; phosphonates stabilize bimetallic ions to prevent aggregation, and B2O3 generated in conjunction with tributyl borate lowers the soot oxidation temperature; at the same time, cleaning components reduce carbon deposits on fuel injectors, ensure uniform fuel atomization, and further enhance the catalytic effect, achieving a dual improvement in fuel saving and emission reduction.

[0040] 2. This invention relies on the structural optimization of ammonolytically modified soybean lecithin, overcoming the limitations of traditional separation of cleaning and repair components. The ammonolysis reaction transforms soybean lecithin into a mono-fatty acid ester structure, enhancing its lipophilicity and dispersibility. Residual hydroxyl groups and phosphonate anions construct a five-membered ring structure, which both masks the anions to prevent precipitation with metal cations and enhances the adsorption of carbon deposits. Its long-chain fatty acids penetrate the pores of carbon deposits, and polar groups disperse and peel off particles. At the same time, the five-membered ring coordinates with the metal surface through phosphorus-oxygen bonds, forming a composite lubricating film that combines toughness and wear resistance, filling micro-scratches, reducing direct friction, and simultaneously achieving carbon deposit removal and component protection.

[0041] 3. This invention employs a composite carrier of myristic acid and stearic acid, leveraging the difference in their melting points to achieve condition-appropriate release of functional components, thus addressing the issue of the dissolution rate of single fatty acid carriers being excessively affected by temperature. During low-temperature startup, the carrier melts slowly, preventing a sudden increase in component concentration that could lead to excessive localized reactions; under high temperature and high load conditions, dissolution is accelerated, ensuring sufficient participation of active components. Combined with the hydrophobic-hydrophilic segment dispersion effect of polyethylene glycol monostearate and the particle refinement effect of ultrasonic processing, each functional component is uniformly distributed in the fuel without agglomeration or precipitation, providing a physical basis for stable performance under all operating conditions.

[0042] 4. This invention optimizes the characteristics of catalytic products from the source, avoiding the harm of traditional additives to the engine and aftertreatment system. The Mn, La, and Ce composite phosphonates generated by the combustion of the composite catalytic unit are soft particles with low Mohs hardness and weak adhesion. They are easily discharged under mechanical impact and fuel flushing, without causing abrasive wear or clogging the three-way catalytic converter and particulate filter. The modified soybean lecithin is derived from plant raw materials and has good biocompatibility. Combined with a low-toxicity additive system, it reduces raw material costs and complies with stringent global environmental regulations on the emission limits of metal particulate matter and pollutants in exhaust gas, thus combining economic efficiency and environmental friendliness.

[0043] 5. This invention ensures the long-lasting effect of additives through component synergy and process enhancement: butylated hydroxyanisole inhibits the oxidative degradation of functional components, polyethylene glycol monostearate prevents particle agglomeration through steric hindrance, ultrasonic dispersion ensures uniform embedding of components in the carrier, avoids storage stratification, the solid particle form facilitates storage and quantitative addition, and each particle is adapted to a fixed amount of fuel, eliminating the need for complex metering tools. It can be directly added to the fuel tank before or after refueling to take effect, solving the problems of easy volatility and cumbersome metering of traditional liquid additives, and is suitable for multiple application scenarios such as passenger cars and commercial vehicles. Attached Figure Description

[0044] Figure 1 This is a product appearance diagram of the high-energy cleaning composite solid fuel additive of the present invention. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0046] Preparation Examples 1-3: Specific Preparation Process of Composite Catalytic Units

[0047] Preparation Example 1: The specific preparation process of the composite catalytic unit includes the following steps:

[0048] (1) Add 6g of diethylphosphonic acid to 18g of ethanol, stir for 10min, then add 3.6g of triethylamine and adjust the pH of the system to 7-8 to obtain a phosphonate solution;

[0049] (2) Add 2.5g manganese chloride, 0.5g lanthanum chloride and 0.15g cerium chloride to 10g deionized water and stir for 10min to obtain a mixed metal salt solution;

[0050] (3) 10g of mixed metal salt solution was added dropwise to 18g of phosphonate solution at a rate of 2ml / min. After the addition was completed, the temperature was raised to 40℃ and the reaction was stirred at a constant temperature for 3h. The precipitate was collected by vacuum filtration, washed and dried to obtain the composite catalytic unit.

[0051] Preparation Example 2: The specific preparation process of the composite catalytic unit includes the following steps:

[0052] (1) Add 5g of diethylphosphonic acid to 20g of ethanol, stir for 15min, then add 3.5g of triethylamine and adjust the pH of the system to 7-8 to obtain a phosphonate solution;

[0053] (2) Add 3g of manganese chloride, 1g of lanthanum chloride and 0.25g of cerium chloride to 15g of deionized water and stir for 15min to obtain a mixed metal salt solution;

[0054] (3) 10g of mixed metal salt solution was added dropwise to 22g of phosphonate solution at a rate of 4ml / min. After the addition was completed, the temperature was raised to 50℃ and the reaction was stirred at a constant temperature for 4h. The precipitate was collected by vacuum filtration, washed and dried to obtain the composite catalytic unit.

[0055] Preparation Example 3: The specific preparation process of the composite catalytic unit includes the following steps:

[0056] (1) Add 4g of diethylphosphonic acid to 20g of ethanol, stir for 20min, then add 3.2g of triethylamine and adjust the pH of the system to 7-8 to obtain a phosphonate solution;

[0057] (2) Add 1.75g ​​manganese chloride, 0.75g lanthanum chloride and 0.175g cerium chloride to 10g deionized water and stir for 20min to obtain a mixed metal salt solution;

[0058] (3) 10g of mixed metal salt solution was added dropwise to 24g of phosphonate solution at a rate of 6ml / min. After the addition was completed, the temperature was raised to 60℃ and the reaction was stirred at a constant temperature for 5h. The precipitate was collected by vacuum filtration, washed and dried to obtain the composite catalytic unit.

[0059] Preparation Examples 4-6: Specific Preparation Process of Modified Soy Lecithin

[0060] Preparation Example 4: The specific preparation method of modified soybean lecithin includes the following steps:

[0061] Add 100g of soybean lecithin and 30g of white oil to a reaction vessel, heat to 70℃, stir for 20min, then add 50g of ethanol and 0.1g of p-toluenesulfonic acid, stir for 5min, then add 10g of diethanolamine, stir and react for 4h, cool to room temperature, remove ethanol by vacuum distillation, add the crude product to 200g of petroleum ether, stir for 30min, wash three times with deionized water, separate the liquid and take the organic phase, dry with anhydrous sodium sulfate, remove the solvent by vacuum distillation, and obtain modified soybean lecithin.

[0062] Preparation Example 5: The specific preparation method of modified soybean lecithin includes the following steps:

[0063] 100g of soybean lecithin and 35g of white oil were added to a reaction vessel, the temperature was raised to 80℃, and the mixture was stirred for 30min. Then 60g of ethanol and 0.2g of p-toluenesulfonic acid were added, and the mixture was stirred for 10min. Then 20g of diethanolamine was added, and the mixture was stirred for 5h. After cooling to room temperature, the ethanol was removed by vacuum distillation. The crude product was added to 300g of petroleum ether and stirred for 45min. The product was washed three times with deionized water. After separation, the organic phase was collected, dried with anhydrous sodium sulfate, and the solvent was removed by vacuum distillation to obtain modified soybean lecithin.

[0064] Preparation Example 6: The specific preparation method of modified soybean lecithin includes the following steps:

[0065] 100g of soybean lecithin and 40g of white oil were added to a reaction vessel, the temperature was raised to 90℃, and the mixture was stirred for 40min. Then 70g of ethanol and 0.3g of p-toluenesulfonic acid were added, and the mixture was stirred for 15min. Then 25g of diethanolamine was added, and the mixture was stirred for 6h. After cooling to room temperature, the ethanol was removed by vacuum distillation. The crude product was added to 400g of petroleum ether and stirred for 60min. The mixture was washed three times with deionized water. After separation, the organic phase was collected, dried with anhydrous sodium sulfate, and the solvent was removed by vacuum distillation to obtain modified soybean lecithin.

[0066] Comparative Preparation Example 1: The difference between Comparative Preparation Example 1 and Preparation Example 2 is that lanthanum chloride and cerium chloride are not added.

[0067] Comparative Preparation Example 2: The difference between Comparative Preparation Example 2 and Preparation Example 2 is that no manganese chloride is added.

[0068] Example 1: A specific preparation method for a high-energy clean composite solid fuel additive, comprising the following steps:

[0069] S1. Mix 650g myristic acid with 100g stearic acid, heat to 70℃ to melt, and stir for 10 minutes to obtain a molten carrier;

[0070] S2. Add 0.75g of the composite catalyst unit prepared according to Preparation Example 1 to the molten support, and stir at an ultrasonic frequency of 40kHz for 20min to obtain mixture A;

[0071] S3. Add 4g of the modified soybean lecithin prepared according to Preparation Example 4 and 1g of tributyl borate to mixture A, stir for 20min to obtain mixture B;

[0072] S4. Add 0.3g butylated hydroxyanisole and 1.5g polyethylene glycol monostearate to mixture B, stir for 20 minutes to obtain mixture C;

[0073] S5. Pour mixture C into a round mold, cool it to 40°C and let it stand for 1 hour, then let it cool naturally to room temperature to solidify. After demolding, you will get a high-energy clean composite solid fuel additive.

[0074] Example 2: A specific preparation method for a high-energy clean composite solid fuel additive, comprising the following steps:

[0075] S1. Mix 700g myristic acid and 125g stearic acid, heat to 75℃ to melt, stir for 15min to obtain molten carrier;

[0076] S2. Add 1g of the composite catalyst unit prepared according to Preparation Example 2 to the molten support, and stir at an ultrasonic frequency of 50kHz for 30min to obtain mixture A;

[0077] S3. Add 5g of the modified soybean lecithin prepared according to Preparation Example 5 and 1.5g of tributyl borate to mixture A, stir for 30min to obtain mixture B;

[0078] S4. Add 0.5g butylated hydroxyanisole and 2g polyethylene glycol monostearate to mixture B, stir for 30 minutes to obtain mixture C;

[0079] S5. Pour mixture C into a round mold, cool it to 40°C and let it stand for 1 hour, then let it cool naturally to room temperature to solidify. After demolding, you will get a high-energy clean composite solid fuel additive.

[0080] Example 3: A specific preparation method for a high-energy clean composite solid fuel additive, comprising the following steps:

[0081] S1. Mix 750g myristic acid with 150g stearic acid, heat to 80℃ to melt, and stir for 20min to obtain a molten carrier;

[0082] S2. Add 1.25g of the composite catalyst unit prepared according to Preparation Example 3 to the molten support, and stir at an ultrasonic frequency of 60kHz for 40min to obtain mixture A;

[0083] S3. Add 6g of the modified soybean lecithin prepared according to Preparation Example 6 and 2g of tributyl borate to mixture A, stir for 40min to obtain mixture B;

[0084] S4. Add 0.8g butylated hydroxyanisole and 2.5g polyethylene glycol monostearate to mixture B, stir for 40min to obtain mixture C;

[0085] S5. Pour mixture C into a round mold, cool it to 40°C and let it stand for 1 hour, then let it cool naturally to room temperature to solidify. After demolding, you will get a high-energy clean composite solid fuel additive.

[0086] Comparative Example 1: The difference between Comparative Example 1 and Example 2 is that the composite catalyst unit prepared according to Preparation Example 2 in Example 2 is replaced with ferrocene, and the amount added is adjusted to 4g.

[0087] Comparative Example 2: The difference between Comparative Example 2 and Example 2 is that the modified soybean lecithin prepared according to Preparation Example 5 in Example 2 is replaced with soybean lecithin.

[0088] Comparative Example 3: The difference between Comparative Example 3 and Example 2 is that the modified soybean lecithin prepared according to Preparation Example 5 is not added.

[0089] Comparative Example 4: The difference between Comparative Example 4 and Example 2 is that the composite catalytic unit prepared according to Preparation Example 2 in Example 2 is replaced with the composite catalytic unit prepared according to Comparative Preparation Example 1.

[0090] Comparative Example 5: The difference between Comparative Example 5 and Example 2 is that the composite catalytic unit prepared according to Preparation Example 2 in Example 2 is replaced with the composite catalytic unit prepared according to Comparative Preparation Example 2.

[0091] Performance testing:

[0092] 1. Catalytic efficiency and fuel economy test

[0093] A 1.6L four-cylinder gasoline engine (maximum power 90kW, maximum torque 155N·m) was selected. The engine was run on a test bench at a standard operating condition of 2000r / min and 50% load. After the engine reached a stable state, fuel additives prepared in Examples 1-3 and Comparative Examples 1-5 were added (at a ratio of 1 capsule / 30L gasoline). A control group without fuel additives was set up. The engine was run continuously for 2 hours, during which fuel consumption was recorded in real time using a fuel consumption meter. The fuel consumption was compared with that of the control group to calculate the fuel saving rate per 100 kilometers. The output power change was measured using an engine dynamometer. The concentrations of CO, HC, and particulate matter (PM2.5) in the exhaust gas were detected using an exhaust gas analyzer. The catalytic combustion and emission reduction effects of different additives were compared. The experimental results are shown in Table 1.

[0094] 2. Carbon Deposit Cleaning Effect Test

[0095] Four identical fuel injectors (0.15mm orifice) and intake valves were taken and subjected to a 10-hour carbon buildup aging test (3000 rpm, 80% load) on the engine used in the above experiment. After disassembly, the initial carbon buildup was recorded by weighing. Subsequently, the carbon-deposited parts were reassembled, and fuel additives prepared in Examples 1-3 and Comparative Examples 1-5 (1 capsule / 30L gasoline) were added respectively. The mixture was run for 8 hours at 2500 rpm and 60% load. The fuel injectors and intake valves were then disassembled, and the residual carbon buildup was ultrasonically cleaned with anhydrous ethanol, dried, and weighed. The carbon buildup reduction rate was calculated. The experimental results are shown in Table 1.

[0096] 3. Engine wear protection test

[0097] A vertical universal friction and wear testing machine was used to simulate the cylinder liner-piston ring friction pair of an engine (material: cylinder liner is gray cast iron, piston ring is chrome-plated steel). The temperature was set at 150℃, the load at 500N, and the speed at 1200r / min. The fuel additives prepared in Examples 1-3 and Comparative Examples 1-5 were added to 92# gasoline at a dosage of 1 capsule / 30L of gasoline as the test lubricating medium. The blank group used pure gasoline. After 4 hours of continuous friction test, the friction pair was disassembled and the wear depth and wear volume of the cylinder liner surface were measured using a high-precision surface profilometer. The experimental results are shown in Table 1.

[0098] 4. Safety testing of products from composite catalytic units

[0099] The fuel additives prepared in Examples 1-3 and Comparative Examples 1-5 were added to the above-mentioned 1.6L displacement engine at a ratio of 1 capsule / 30L gasoline. After running continuously for 50 hours, the three-way catalytic converter (TWC) and diesel particulate filter (DPF, adapted for modified models) were disassembled, and the amount of solid particles deposited in the DPF was measured by weighing. At the same time, the change in the conversion efficiency of TWC for CO and HC compared with that before the addition of fuel additives was tested. The experimental results are shown in Table 1.

[0100] Table 1 Performance Test Results

[0101]

[0102] Performance Analysis:

[0103] As can be seen from the data in Table 1, the high-energy cleaning composite solid fuel additives prepared using the present invention in Examples 1-3 exhibit excellent performance in core aspects such as catalytic combustion, carbon deposit cleaning, wear protection, and product safety. Essentially, this is achieved through the complementary microscopic effects of multiple components and process enhancement, solving the problems of low catalytic efficiency, incomplete cleaning, high wear risk, and easy product deposition in traditional additives. Example 2 shows the best performance; the balanced synergistic relationship between the components avoids both cost waste due to excessive component dosage and functional degradation caused by insufficient dosage, resulting in optimal catalytic activity of the composite catalytic unit, dispersion of cleaning components, stability of the lubricating film, and product discharge.

[0104] The results of the catalytic efficiency and fuel economy tests show that Example 2 performs better. This may be because the Mn in the composite catalytic unit of Example 2... 2+ As a redox active center, it passes through in the early stage of combustion The reversible valence state cycle transfers electrons, directly lowering the breaking energy barriers of C-C and CH bonds in fuel hydrocarbons, and rapidly initiating the combustion chain reaction; La 3+ / Ce 3+ This process efficiently adsorbs and activates oxygen molecules through lattice oxygen vacancies, generating active species such as superoxide anions and hydroxyl radicals. These precisely oxidize incomplete combustion products such as carbon monoxide and soot precursors. Meanwhile, the phosphonate ligand stabilizes the bimetallic ions through coordination bonds, preventing premature aggregation and loss of active centers. In contrast, Comparative Example 1 uses ferrocene that relies solely on Fe... 2+The single-valence-state cycle lacks the synergistic oxygen activation of rare earth ions, resulting in a narrow catalytic spectrum and easily degraded active centers. The hard Fe2O3 particles generated during combustion also disrupt fuel atomization, leading to low combustion efficiency. In Comparative Example 2, the unmodified soybean lecithin, due to its poor dispersibility of the di-fatty acid ester structure, cannot effectively clean carbon deposits. The clogging of the fuel injectors leads to uneven fuel atomization, indirectly reducing catalytic efficiency. In Comparative Example 3, due to the lack of cleaning components, carbon deposits accumulate more severely, hindering fuel flow and atomization, resulting in even lower efficiency. In Comparative Example 4, the single Mn catalytic unit lacks La / Ce oxygen vacancy regulation, resulting in low active oxygen species generation and weak oxidation ability for soot precursors, leading to a high proportion of incomplete combustion products. In Comparative Example 5, the Mn-free catalytic unit lacks redox active centers and cannot initiate the combustion chain reaction. Relying solely on the combustion-supporting effect of rare earth ions, its catalytic efficiency is far lower than that of Example 2.

[0105] The powerful cleaning effect of Example 2 is rooted in the structural optimization and mechanism of action of modified soybean lecithin: the ammonolysis reaction converts the di-fatty acid esters of soybean lecithin into mono-fatty acid esters, reducing the molecular weight and increasing lipophilicity. Simultaneously, the residual hydroxyl groups form a five-membered ring phosphonate structure with the phosphonate anions, both masking the anions to prevent precipitation with metal cations and enhancing the adsorption of carbon deposits. The polar groups, such as the fatty amide groups and phosphonic acid groups, can penetrate into the carbon deposit pores, disrupting the network structure of carbon deposits through van der Waals forces and electrostatic attraction. Then, with the dispersion effect of the hydrophobic-hydrophilic segments of polyethylene glycol monostearate, the detached micro-carbon deposit particles are discharged with the fuel. In contrast, the ferrocene in Comparative Example 1 has no cleaning function; it can only weakly catalyze the reduction of new carbon deposit formation and is ineffective against existing carbon deposits. The lack of carbon stripping effect resulted in poor cleaning performance. In Comparative Example 2, the unmodified soybean lecithin, due to the excessive hydrophobicity of its fatty acid ester chains, easily aggregated molecules with insufficient exposure of polar groups, resulting in weak penetration and adsorption capabilities. Furthermore, at high temperatures, it was prone to ester group breakage, generating gum that exacerbated carbon deposits, leading to low cleaning efficiency. Comparative Example 3, lacking cleaning components, relied solely on fuel flushing, failing to effectively target dense carbon deposits, thus resulting in a low carbon deposit reduction rate. While the single Mn catalytic unit in Comparative Example 4 could alleviate new carbon deposit formation by reducing carbon deposit precursors, the lack of active penetration and stripping by modified lecithin meant its cleaning ability for old carbon deposits was weaker than in Example 2. In Comparative Example 5, the Mn-free catalytic unit could not inhibit carbon deposit precursor formation, resulting in a carbon deposit formation rate far exceeding the cleaning rate, leading to high cleaning pressure and poor performance.

[0106] The wear protection in Example 2 stems from the dual guarantee of lubricant film construction and low wear product regulation: the long-chain fatty acids of modified soybean lecithin can form a physical adsorption film on the cylinder liner-piston ring friction pair surface; the five-membered cyclic phosphonate reacts with the metal surface through phosphorus-oxygen bonds to construct an organic-inorganic composite lubricant film with both toughness and wear resistance, filling the microscopic scratches on the metal surface; at the same time, the Mn, La, Ce composite phosphonate products generated by the combustion of the composite catalytic unit are soft particles with low Mohs hardness and good dispersibility, and will not produce abrasive wear; in contrast, the ferrocene in Comparative Example 1 generates Fe2O3 particles by combustion, with a Mohs hardness as high as 5.0-5.5, which form sharp abrasives during friction, aggravating cutting. Wear and tear resulted in higher wear levels. In Comparative Example 2, the adsorption film formed by unmodified soybean lecithin was easily extruded under high load due to weak intermolecular forces, resulting in uneven film thickness and poor stability, thus its protective effect was weaker than that of Example 2. In Comparative Example 3, due to the lack of lubricating and repairing components, there was no effective protective film on the surface of the friction pair, and the metal directly engaged in contact, resulting in significantly higher wear. In Comparative Example 4, the single Mn catalytic unit product lacked La / Ce lattice regulation, making it prone to agglomeration and forming larger particles, increasing hardness and increasing the wear risk compared to Example 2. In Comparative Example 5, the lack of Mn catalytic unit only left La / Ce oxides, which had a high Mohs hardness and was prone to agglomeration due to the lack of ligand regulation, causing significant wear to the friction pair and resulting in poor protective effect.

[0107] The key to the product safety in Example 2 lies in the ligand regulation and dispersion enhancement of the composite catalytic unit, and the PO4 generated by the combustion of the phosphonate ligand. 3- Combined with bimetallic oxides, it forms composite phosphonate particles, which are uniformly dispersed under the steric hindrance of polyethylene glycol monostearate. These particles are easily expelled from the engine with the combustion airflow, preventing accumulation and blockage within the DPF, and avoiding chemical bonding or physical covering with the Pt, Rh, and other noble metal active sites of TWC, thus ensuring its catalytic conversion efficiency. In Comparative Example 1, ferrocene combustion produces Fe2O3 particles, which are large and hard, easily forming dense packing within the DPF. Simultaneously, Fe2O3 forms alloys with the noble metals of TWC, resulting in lower conversion efficiency for CO and HC. In Comparative Example 2, unmodified soybean lecithin phosphonate... Anions are not masked and easily form precipitates with metal cations in fuel. The precipitate particles are deposited on the surface of DPF and TWC with the airflow, resulting in a higher risk of clogging and an activity inhibition effect than in Example 2. In Comparative Example 3, due to the lack of cleaning components, a large number of carbon deposit particles are generated, further aggravating DPF clogging and TWC pollution. In Comparative Example 4, the single Mn catalytic unit products lack La / Ce dispersion regulation and are prone to agglomeration to form larger particles, resulting in a higher DPF deposition. In Comparative Example 5, the Mn-free catalytic unit only has residual rare earth oxides, which have strong agglomeration and large particle size, and are deposited in large quantities on the TWC surface, significantly reducing the utilization rate of active sites and having a lower safety than in Example 2.

[0108] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A high-energy, clean-type composite solid fuel additive, characterized in that, The raw materials include the following parts by weight: myristic acid: 65-75 parts, stearic acid: 10-15 parts, composite catalytic unit: 0.075-0.125 parts, modified soybean lecithin: 0.4-0.6 parts, tributyl borate: 0.1-0.2 parts, butylated hydroxyanisole: 0.03-0.08 parts, and polyethylene glycol monostearate: 0.15-0.25 parts; The preparation method of the composite catalytic unit is as follows: (1) Add diethylphosphonic acid to ethanol, stir for 10-20 min, add triethylamine, adjust the pH of the system to 7-8, and obtain a phosphonate solution; (2) Add manganese chloride, lanthanum chloride and cerium chloride to deionized water and stir for 10-20 min to obtain a mixed metal salt solution; (3) Add the mixed metal salt solution dropwise into the phosphonate solution. After the addition is complete, raise the temperature to 40-60℃ and stir the reaction at a constant temperature for 3-5 hours. Collect the precipitate by filtration, wash and dry it to obtain the composite catalytic unit. The modified soybean lecithin is prepared as follows: Add soybean lecithin and white oil to the reaction vessel, heat to 70-90℃, stir for 20-40 min, then add ethanol and p-toluenesulfonic acid, stir for 5-15 min, then add diethanolamine, stir and react for 4-6 h, cool to room temperature, remove ethanol by vacuum distillation, add the crude product to petroleum ether, stir for 30-60 min, wash 3 times with deionized water, separate the liquid and take the organic phase, dry with anhydrous sodium sulfate, remove the solvent by vacuum distillation, and obtain modified soybean lecithin; The preparation method of the high-energy clean composite solid fuel additive is as follows: S1. Mix myristic acid and stearic acid, heat to 70-80℃ to melt, and stir for 10-20 minutes to obtain a molten carrier; S2. Add the composite catalytic unit to the molten support and stir under ultrasonication for 20-40 min to obtain mixture A; S3. Add the modified soybean lecithin and tributyl borate to mixture A, stir for 20-40 minutes to obtain mixture B; S4. Add butylated hydroxyanisole and polyethylene glycol monostearate to mixture B, stir for 20-40 min to obtain mixture C; S5. Pour mixture C into a round mold, cool it to 40°C and let it stand for 1 hour, then let it cool naturally to room temperature to solidify. After demolding, you will get a high-energy clean composite solid fuel additive.

2. The high-energy clean composite solid fuel additive according to claim 1, characterized in that, The molecular formula of the polyethylene glycol monostearate is HO(CH2CH2O). n OCC 17 H 35 , where n≈10.

3. The high-energy clean composite solid fuel additive according to claim 1, characterized in that, In (1), the weight ratio of diethylphosphonic acid, ethanol and triethylamine is 1:3-5:0.6-0.

8.

4. The high-energy clean composite solid fuel additive according to claim 1, characterized in that, In (2), the weight ratio of manganese chloride, lanthanum chloride, cerium chloride and deionized water is 5-7:1-3:0.3-0.7:20-40.

5. The high-energy clean composite solid fuel additive according to claim 1, characterized in that, In step (3), the mixed metal salt solution and hypophosphite solution are in a weight ratio of 1:1.8-2.

4.

6. The high-energy clean composite solid fuel additive according to claim 1, characterized in that, The dripping rate of the mixed metal salt solution into the hypophosphite solution in (3) is 2-6 ml / min.

7. The high-energy clean composite solid fuel additive according to claim 1, characterized in that, In the preparation method of the composite catalytic unit, soybean lecithin, white oil, ethanol, p-toluenesulfonic acid, diethanolamine and petroleum ether are in a weight ratio of 1:0.3-0.4:0.5-0.7:0.001-0.003:0.1-0.25:2-4.

8. The high-energy clean composite solid fuel additive according to claim 1, characterized in that, The ultrasonic frequency in S2 is 40-60kHz.

9. The high-energy clean composite solid fuel additive according to claim 1, characterized in that, The high-energy clean composite solid fuel additive in S5 has a single particle weight of 1.5-2.0g. It can be added directly to the fuel tank before or after refueling, and each particle can be mixed with 30 liters of gasoline.

Images