Preparation method of alcohol-based fuel

Abstract

The invention relates to the technical field of preparation of alcohol-based fuel for automobiles, in particular to a preparation method of alcohol-based fuel with a high methanol ratio for automobiles and a preparation method of the alcohol-based fuel with the high methanol ratio for automobiles, and solves the problems that the alcohol-based fuel is difficult to mix, easy to layer at low temperature and easy to layer after absorbing water. The alcohol-based fuel is prepared by mixing an additive, methanol and toluene, wherein the additive is prepared from a cosolvent, a dispersant, a modifier and other raw materials.

Description

Technical Field

[0001] This invention relates to the field of alcohol-based fuels, and more particularly to a method for preparing an alcohol-based fuel for automobiles with a high methanol content. Background Technology

[0002] Traditional gasoline, as the mainstream energy source for vehicles, is widely used, but its drawbacks are becoming increasingly apparent. Because gasoline itself does not contain oxygen, it often relies on external air for combustion, which can easily lead to incomplete combustion and produce large amounts of harmful emissions such as carbon monoxide, hydrocarbons, and particulate matter. This not only pollutes the environment but also reduces engine thermal efficiency. Furthermore, as a petroleum-derived product, gasoline supply is constrained by the geographical distribution and price fluctuations of crude oil resources, resulting in high costs and unsustainability. In contrast, alcohol-based fuels exhibit significant advantages. Since alcohol molecules themselves contain oxygen atoms (e.g., methanol contains up to 50% oxygen), combustion allows for a more complete oxidation reaction, significantly reducing the formation of incomplete combustion products, thereby reducing exhaust pollution and improving combustion efficiency. At the same time, alcohol-based fuels have a wider range of sources. For example, methanol can be synthesized from carbon dioxide in coal, natural gas, or even industrial waste gas through hydrogenation, while ethanol can be extracted from crops or cellulosic biomass, providing flexible and renewable raw material supply. In terms of cost, the production processes of methanol and other alcohol fuels are mature, and their prices are generally lower than gasoline, making them particularly economical in regions rich in chemical resources. These characteristics make alcohol-based fuels a viable option for addressing energy security and environmental issues.

[0003] Alcohol-based fuels have the following advantages over traditional petroleum-based gasoline:

[0004] (1) Clean combustion of alcohol-based fuels

[0005] Alcohol-based fuels primarily consist of low-molecular-weight alcohols, with methanol (CH3OH) containing up to 50% oxygen and ethanol (C2H5OH) containing 34.7% oxygen. During combustion, they provide their own oxygen source, significantly improving oxidation efficiency. Experiments show that methanol fuel can reduce CO emissions by more than 50% compared to gasoline, with near-zero soot emissions.

[0006] (2) The base vehicle fuel has excellent low-temperature combustion characteristics:

[0007] Alcohol-based fuels have high latent heat of vaporization (methanol 1109 kJ / kg, gasoline about 350 kJ / kg), which can reduce in-cylinder temperature and reduce NOx formation (by 30-50%).

[0008] (3) The renewable and diverse raw material sources of base vehicle fuels

[0009] The main component of alcohol-based fuels is methanol, which can be produced from fossil fuels such as coal and natural gas. This aligns with my country's energy endowment, which is rich in coal but poor in oil, with the cost of coal-to-methanol production being approximately 2000 yuan / ton.

[0010] Green path: Use renewable energy to electrolyze water to produce hydrogen, and then combine it with CO2 captured from industry to synthesize "electro-methanol" to achieve carbon cycle.

[0011] (4) Low fuel cost for vehicles ensures national energy security.

[0012] In 2023, the market price of methanol in China was approximately 2,500-3,000 yuan per ton, equivalent to 60-70% of the price of gasoline in terms of energy equivalent. Moreover, China's methanol production capacity accounts for more than 60% of the global total, which can reduce dependence on imported crude oil; for example, in 2022, my country's dependence on imported crude oil reached 72%. Using methanol as fuel can further ensure national energy security.

[0013] (5) Excellent combustion performance of base vehicle fuel

[0014] High octane rating: Methanol RON reaches 109, ethanol RON 111, which can be directly used in high compression ratio (12:1 and above) engines to improve thermal efficiency. Flexible fuel technology: such as the Brazilian Flex-Fuel vehicle, which can automatically adjust the fuel injection strategy and is compatible with any ratio of ethanol gasoline from E20 to E100.

[0015] In summary, methanol-based fuels, with methanol as the main component, have significant advantages and are a major alternative to traditional gasoline, showing broad application prospects. However, during the preparation of methanol gasoline, the large polarity difference between methanol and gasoline, coupled with an unsuitable ratio, leads to poor micro-dispersion and easy stratification at low temperatures. Therefore, the significant polarity difference between methanol and gasoline makes mixing difficult, and the fuels are prone to stratification at low temperatures and absorbing water, severely hindering the widespread application of methanol-based fuels.

[0016] In the blending of alcohol-based fuels, methanol, which is inexpensive, is used in the largest quantity. Methanol is a highly polar molecule. Its hydroxyl group (-OH) is a highly polar functional group, and the oxygen atom is highly electronegative, resulting in one end of the molecule carrying a partial negative charge, while the hydrogen atom carries a partial positive charge at one end. Furthermore, strong hydrogen bonds exist between methanol molecules. Hydrogen bonds are a very strong dipole-dipole interaction, much stronger than ordinary van der Waals forces. This makes methanol molecules very "sticky" and has high cohesive energy. Therefore, methanol is hydrophilic; due to its polarity, methanol and water are infinitely miscible, forming extremely strong hydrogen bonds. Consequently, methanol readily absorbs water spontaneously.

[0017] However, gasoline, as another component of alcohol-based fuels, is a typical nonpolar mixture, a complex mixture of various hydrocarbons (such as alkanes, cycloalkanes, and aromatics). These molecules are composed of carbon and hydrogen with very small differences in electronegativity, thus exhibiting overall nonpolarity. Intermolecular forces consist only of weak van der Waals forces. The "stickiness" between molecules is very low. Due to its nonpolarity, gasoline is immiscible with water and will separate into layers.

[0018] Based on the above fundamental differences, alcohol-based fuels are difficult to mix, prone to stratification at low temperatures, and prone to stratification when absorbing water.

[0019] (1) Difficulty in mixing methanol and gasoline

[0020] In the preparation of alcohol-based fuels, even when methanol and gasoline are forcibly mixed through mechanical stirring, the resulting mixture easily separates after settling, failing to form a homogeneous and stable solution. This is because the mixing process presents a significant energy barrier. Dispersing methanol molecules into gasoline requires overcoming the strong hydrogen bonds between methanol molecules. This necessitates additional energy input, such as vigorous mechanical stirring or heating. Moreover, the entropy increase driving force of the mixing process is limited. Although the mixing process is thermodynamically an entropy-increasing process, favoring spontaneous occurrence, enthalpy change plays a dominant role here.

[0021] During mixing, the previously strong methanol-methanol hydrogen bonds and gasoline-gasoline van der Waals forces are broken, requiring energy absorption. However, the newly formed intermolecular forces between methanol and gasoline molecules—induced dipole interactions—are very weak, releasing far less energy than required to break the original forces. Therefore, the entire mixing process is endothermic (ΔH>0) and non-spontaneous at room temperature. This leads to easy phase separation of alcohol-based fuels.

[0022] (2) Alcohol-based fuels are prone to phase separation and stratification under low temperature conditions.

[0023] Even if a seemingly homogeneous mixture is formed at room temperature (M15, M85 methanol gasoline), the mixture will become cloudy and eventually separate into two distinct layers when the ambient temperature decreases.

[0024] This is due to the relationship between temperature and solubility: for most dissolution processes, especially endothermic ones like this one, solubility decreases as temperature decreases. Furthermore, as temperature decreases, molecular kinetic energy decreases, and the average kinetic energy of the molecules decreases. The methanol particles that were initially barely "suspended" in gasoline due to kinetic energy now have reduced mobility.

[0025] At low temperatures, thermal perturbations weaken, and the influence of intermolecular forces becomes more significant. The tendency for methanol molecules to form hydrogen bonds is greatly enhanced, surpassing the hybrid power effect brought about by entropy.

[0026] Therefore, at low temperatures, existing alcohol-based fuels are prone to phase separation. Methanol molecules violently seek each other out and aggregate, forming larger methanol droplets, which eventually precipitate completely from the gasoline, forming an upper gasoline phase and a lower methanol-rich phase. The lower the temperature, the more thorough and rapid the separation.

[0027] (3) Alcohol-based fuels are prone to separation after absorbing water at room temperature.

[0028] Existing methanol-gasoline blends are extremely sensitive to trace amounts of moisture in the environment. Even a tiny amount of water can immediately trigger stratification, which is one of the most challenging problems in the storage, transportation, and use of methanol-gasoline.

[0029] Methanol itself is highly hydrophilic and actively absorbs moisture from the air. During storage and transportation, respiration can introduce humid air into the fuel system, where the water vapor is absorbed by the methanol.

[0030] Water and methanol have a stronger binding force; both are highly polar molecules and contain hydroxyl groups. The hydrogen bonds formed between them are much stronger than the forces between methanol and gasoline, or water and gasoline. When water enters the system, it forms a more stable phase. When water molecules enter the system, they strongly bind with methanol molecules, forming a "methanol-water" complex. The hydrogen bond network within this complex is very stable, and its polarity differs more significantly from that of non-polar gasoline, resulting in poorer compatibility.

[0031] Once the layers separate, the lower aqueous phase can cause corrosion of the metal canister, engine corrosion, and damage to the fuel pump. Simultaneously, the lower layer is a methanol-water solution. If this liquid enters the engine, it can cause starting difficulties, a severe drop in power, or even engine stalling.

[0032] To overcome these problems, the alcohol-based gasoline prepared in this invention incorporates co-solvents or phase dispersants. These co-solvents have a slightly polar molecular structure at one end (-OH), enabling them to react with methanol and water; the other end has a longer carbon chain, allowing them to be compatible with gasoline. Acting as "emulsifiers" or "bridges," they reduce the interfacial tension between methanol and gasoline, improve the stability of the mixture, and delay the tendency for stratification at low temperatures and in the presence of trace amounts of water. This invention patent plays a significant role in promoting the application of alcohol-based fuels. Summary of the Invention

[0033] The technical problem to be solved by the present invention is to provide an alcohol-based fuel for automobiles with a high methanol content and a method for preparing the same, thereby solving the problems of difficult mixing, easy stratification at low temperatures, and easy stratification due to water absorption in alcohol-based fuels.

[0034] This invention provides an alcohol-based fuel and its preparation method. The alcohol-based fuel provided by this invention has the advantages of deep dispersion, high water solubility, and long stability time.

[0035] 1. An alcohol-based fuel, prepared by mixing additives, methanol, and toluene; wherein the additives are prepared from raw materials such as co-solvents, dispersants, and modifiers, characterized in that:

[0036] The co-solvent includes at least one of ethylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ether, propylene glycol methyl ethyl ether, dioxane, and benzyl alcohol; wherein the volume ratio of ethylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ether, dioxane, and benzyl alcohol is 0-1:0-1:0-1:0-1:0-1:0-1;

[0037] The dispersant is an ethylene glycol-succinic acid oligomer reaction mixture obtained by rapid esterification reaction of ethylene glycol and succinic acid, mainly consisting of oligomers with 2 to 4 polymer units, as well as unreacted ethylene glycol and butyric acid.

[0038] The modifier includes a metal corrosion inhibitor; the metal corrosion inhibitor is prepared by dissolving one or more of cyclohexylamine, aniline and benzo[a]azole in a small amount of methanol.

[0039] The cosolvent, dispersant and modifier are mixed in a ratio of 1-10:1-5:0.1-2 and then subjected to ultrasonic treatment. The ultrasonic dispersion time is 8-15 min and the ultrasonic power is 500-600 W.

[0040] 2. The alcohol-based fuel is characterized in that the methanol content in the alcohol-based fuel is 90-95% by mass; the remaining components are prepared according to the mass ratio of additives, methanol and toluene of 0.5-10:85-95:5-15.

[0041] 3. A method for preparing alcohol-based fuels, comprising the following steps:

[0042] A) The additive is obtained by mixing, ultrasonically dispersing, and mixing and dispersing the cosolvent, dispersant, and modifier.

[0043] B) Mix the additive, gasoline and methanol, stir for a period of time and then ultrasonically disperse to obtain alcohol-based fuel. The ultrasonic dispersion time is 15-30 min and the ultrasonic power is 500-600 W.

[0044] 4. An alcohol-based fuel, characterized in that the reaction conditions for preparing the dispersant are:

[0045] The oligomerization reaction was carried out in a reactor equipped with a water separator and a reflux condenser. Toluene was added to the water separator and nitrogen was introduced as a stirring gas, which helped to remove the water vapor generated in the reaction and accelerate the dehydration process.

[0046] According to the molar ratio, the raw materials are weighed and added to the reactor in a ratio of n(ethylene glycol):n(succinic acid) = 1.1:1.0 to 1.5:1.0. The excess ethylene glycol ensures that the number of hydroxyl groups (-OH) in the system is greater than that of carboxyl groups (-COOH). During the polymerization process, each chain will have hydroxyl groups at both ends, thus effectively terminating chain growth and obtaining oligomers with lower molecular weight. Then, p-toluenesulfonic acid is added to the reactor in an amount of 0.5% to 2% of the mass of succinic acid. The reaction temperature is controlled at 160℃-190℃, and the reaction time is controlled at 1 to 4 hours.

[0047] After the reaction time is up, heating is stopped, and the reaction mixture is washed with water to remove residual catalyst, yielding a dispersant. Detailed Implementation

[0048] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] This invention provides an alcohol-based fuel, prepared from raw materials including gasoline, cosolvent, dispersant, modifier, methanol, and gasoline;

[0050] In some embodiments of the present invention, the co-solvent includes at least one selected from ethylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ether, propylene glycol methyl ethyl ether, dioxane, and benzyl alcohol; the volume ratio of the ethylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ether, propylene glycol methyl ethyl ether, dioxane, and benzyl alcohol is 0–1:0–1:0–1:0–1:0–1. In some embodiments of the present invention, the co-solvent can be obtained by stirring and mixing at least one selected from ethylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ethyl ether, dioxane, and benzyl alcohol.

[0051] In some embodiments, the co-solvent comprises ethylene glycol methyl ether, dioxane, and benzyl alcohol in a volume ratio of 1:1 to 2:1:1 to 2. In some embodiments, the volume ratio of ethylene glycol methyl ether, dioxane, and benzyl alcohol is 1:1:1:1, 1:2:1:2, or 1:2:1:1.

[0052] In some embodiments of the present invention, the dispersant is an ethylene glycol-succinic acid oligomer reaction mixture obtained by rapid esterification reaction of ethylene glycol and succinic acid, mainly comprising oligomers with 2 to 4 polymeric units, and at least one of unreacted ethylene glycol and butyric acid; the ethylene glycol-succinic acid oligomer has 2 to 4 polymeric units, typically 2 to 3. In some embodiments of the present invention, the dispersant can be prepared from the ethylene glycol-succinic acid oligomer reaction mixture. Raw materials are weighed according to a molar ratio of n(ethylene glycol):n(succinic acid) = 1.1:1.0 and added to a reactor; then p-toluenesulfonic acid is added in an amount of 0.5% to 2% of the mass of succinic acid; the reaction temperature is controlled at 160°C-190°C; and the reaction time is controlled at 1 to 4 hours.

[0053] In some embodiments of the present invention, the modifier includes a metal corrosion inhibitor. The metal corrosion inhibitor is prepared by dissolving one or more of cyclohexylamine, aniline, and benzo[a]azole in a small amount of methanol.

[0054] The present invention does not impose any special restrictions on the type and source of the gasoline, and commercially available chemical raw materials such as methanol and toluene can be used.

[0055] In some embodiments of the present invention, the cosolvent, dispersant, and modifier are disposed in a ratio of 1–10:1–5:0.1–2. In some embodiments, the mass ratio of the cosolvent, dispersant, modifier, methanol, and gasoline is 0.5:0.075:0.5:13:43, 0.5:0.075:0.5:14:25, 0.7:0.065:0.3:13:25, or 0.6:0.07:0.4:15:35.

[0056] The fuel provided by this invention has a high oxygen content, approximately 40-50 wt%.

[0057] The present invention does not impose any special restrictions on the source of the raw materials used above, and they can be commercially available.

[0058] The alcohol-based fuel provided by this invention has a methanol content in the range of 90-95 wt%, high oxygen content, long stability time, and can be stably burned in engines.

[0059] The alcohol-based fuel provided by this invention does not contain metal additives, has a sulfur content of less than 10 μg / g, and the additives are mainly oxygen-containing compounds. Furthermore, methanol is the main component of the fuel. Because methanol has the advantages of being widely available, low in cost, and low in toxicity, the gasoline engine fuel provided by this invention is a stable fuel.

[0060] The gasoline component obtained by the above-mentioned compound containing multiple polar components, under the action of the dispersant and cosolvent, can form an alcohol-based fuel with small particle size and long stability time. In addition, the preparation method provided by the present invention is simple to operate.

[0061] To further illustrate the present invention, the following detailed description of an alcohol-based fuel and its preparation method provided by the present invention is provided in conjunction with embodiments, but it should not be construed as limiting the scope of protection of the present invention.

[0062] All raw materials used in the following examples are commercially available.

[0063] The gasoline used in the examples was selected from toluene, a commercially available product of Jingbo Petrochemical Company.

[0064] Example 1

[0065] 1. An alcohol-based fuel is prepared by mixing additives, methanol, and toluene. The additives are prepared from raw materials such as co-solvents, dispersants, and modifiers. Its characteristics are:

[0066] The co-solvent includes ethylene glycol methyl ether, dioxane, and benzyl alcohol, with a volume ratio of ethylene glycol methyl ether, dioxane, and benzyl alcohol of 1:1 to 2:1.

[0067] The dispersant is an ethylene glycol-succinic acid oligomer reaction mixture obtained by rapid esterification reaction of ethylene glycol and succinic acid, mainly consisting of oligomers with 2 to 4 polymer units, as well as unreacted ethylene glycol and butyric acid.

[0068] The modifier includes a metal corrosion inhibitor; the metal corrosion inhibitor is prepared by dissolving one or more of cyclohexylamine, aniline and benzo[a]azole in a small amount of methanol.

[0069] The cosolvent, dispersant and modifier are mixed in a ratio of 10:4:1 and then subjected to ultrasonic treatment. The ultrasonic dispersion time is 10 min and the ultrasonic power is 600 W.

[0070] 2. The alcohol-based fuel is characterized in that the methanol content in the alcohol-based fuel is 90% by mass; the remaining components are prepared by mixing additives, methanol and toluene in a mass ratio of 5:90:5.

[0071] 3. A method for preparing alcohol-based fuels, comprising the following steps:

[0072] A) The additive is obtained by mixing, ultrasonically dispersing, and mixing and dispersing the cosolvent, dispersant, and modifier.

[0073] B) Mix the additive, gasoline and methanol, stir for a period of time and then ultrasonically disperse to obtain alcohol-based fuel. The ultrasonic dispersion time is 30 min and the ultrasonic power is 600 W.

[0074] 4. An alcohol-based fuel, characterized in that the preparation reaction conditions of the dispersant are as follows:

[0075] The oligomerization reaction was carried out in a reactor equipped with a water separator and a reflux condenser. Toluene was added to the water separator and nitrogen was introduced as a stirring gas, which helped to remove the water vapor generated in the reaction and accelerate the dehydration process.

[0076] According to the molar ratio of ethylene glycol:n(succinic acid) = 1.1:1.0, the raw materials are weighed and added to the reactor. Then, p-toluenesulfonic acid is added to the reactor at a rate of 1% of the mass of succinic acid. The reaction temperature is controlled at 180℃ and the reaction time is controlled at 4 hours.

[0077] After the reaction time is up, heating is stopped, and the reaction mixture is washed with water to remove residual catalyst, yielding a dispersant.

[0078] Example 2

[0079] 1. An alcohol-based fuel, prepared by mixing additives, methanol, and toluene; wherein the additives are prepared from raw materials such as co-solvents, dispersants, and modifiers, characterized in that:

[0080] The co-solvent includes ethylene glycol methyl ether, dioxane, and benzyl alcohol, with a volume ratio of ethylene glycol methyl ether, dioxane, and benzyl alcohol of 1:1:1.

[0081] The dispersant is an ethylene glycol-succinic acid oligomer reaction mixture obtained by rapid esterification reaction of ethylene glycol and succinic acid, mainly consisting of oligomers with 2 to 4 polymer units, as well as unreacted ethylene glycol and butyric acid.

[0082] The modifier includes a metal corrosion inhibitor; the metal corrosion inhibitor is prepared by dissolving one or more of cyclohexylamine, aniline and benzo[a]azole in a small amount of methanol.

[0083] The cosolvent, dispersant and modifier are mixed in a ratio of 5:5:1 and then subjected to ultrasonic treatment. The ultrasonic dispersion time is 10 minutes and the ultrasonic power is 500W.

[0084] 2. An alcohol-based fuel, characterized in that the alcohol-based fuel contains 90% methanol by mass; its components are prepared by mixing additives, methanol and toluene in a mass ratio of 4:90:6.

[0085] 3. A method for preparing alcohol-based fuels, comprising the following steps:

[0086] A) The additive is obtained by mixing, ultrasonically dispersing, and mixing and dispersing the cosolvent, dispersant, and modifier.

[0087] B) Mix the additive, gasoline and methanol, stir for a period of time and then ultrasonically disperse to obtain alcohol-based fuel. The ultrasonic dispersion time is 30 min and the ultrasonic power is 500 W.

[0088] 4. An alcohol-based fuel, characterized in that the preparation reaction conditions of the dispersant are as follows:

[0089] The oligomerization reaction was carried out in a reactor equipped with a water separator and a reflux condenser. Toluene was added to the water separator and nitrogen was introduced as a stirring gas, which helped to remove the water vapor generated in the reaction and accelerate the dehydration process.

[0090] Weigh the raw materials according to the molar ratio of ethylene glycol:n(succinic acid) = 1.2:1.0 and add them to the reactor; then add p-toluenesulfonic acid to the reactor, the amount of which is 2% of the mass of succinic acid; control the reaction temperature at 190℃; control the reaction time at 3 hours.

[0091] After the reaction time is up, heating is stopped, and the reaction mixture is washed with water to remove residual catalyst, yielding a dispersant.

[0092] Example 3

[0093] 1. An alcohol-based fuel, prepared by mixing additives, methanol, and toluene; wherein the additives are prepared from raw materials such as co-solvents, dispersants, and modifiers, characterized in that:

[0094] The co-solvent includes propylene glycol methyl ethyl ether, dioxane, and benzyl alcohol, with a volume ratio of propylene glycol methyl ethyl ether, dioxane, and benzyl alcohol of 1:1:1.

[0095] The dispersant is an ethylene glycol-succinic acid oligomer reaction mixture obtained by rapid esterification reaction of ethylene glycol and succinic acid, mainly consisting of oligomers with 2 to 4 polymer units, as well as unreacted ethylene glycol and butyric acid.

[0096] The modifier includes a metal corrosion inhibitor; the metal corrosion inhibitor is prepared by dissolving one or more of cyclohexylamine, aniline and benzo[a]azole in a small amount of methanol.

[0097] The cosolvent, dispersant and modifier are mixed in a ratio of 2:1:0.5 and then subjected to ultrasonic treatment. The ultrasonic dispersion time is 10 min and the ultrasonic power is 500 W.

[0098] 2. An alcohol-based fuel, characterized in that the alcohol-based fuel contains 95% methanol by mass; the remaining components are prepared according to an additive, methanol and toluene mass ratio of 2:95:3.

[0099] 3. A method for preparing alcohol-based fuels, comprising the following steps:

[0100] A) The additive is obtained by mixing, ultrasonically dispersing, and mixing and dispersing the cosolvent, dispersant, and modifier.

[0101] B) Mix the additive, gasoline and methanol, stir for a period of time and then ultrasonically disperse to obtain alcohol-based fuel. The ultrasonic dispersion time is 30 min and the ultrasonic power is 600 W.

[0102] 4. An alcohol-based fuel, characterized in that the preparation reaction conditions of the dispersant are as follows:

[0103] Oligopolymerization was carried out in a reactor equipped with a water separator and a reflux condenser. Toluene was added to the water separator and nitrogen was introduced as a stirring gas to accelerate the dehydration process.

[0104] According to the molar ratio of ethylene glycol:n(succinic acid) = 1.4:1.0, the raw materials are weighed and added to the reactor. Then, p-toluenesulfonic acid is added to the reactor at a rate of 0.5% of the mass of succinic acid. The reaction temperature is controlled at 160℃ and the reaction time is controlled at 2 hours.

[0105] After the reaction time is up, heating is stopped, and the reaction mixture is washed with water to remove residual catalyst, yielding a dispersant.

[0106] Example 4

[0107] 1. An alcohol-based fuel, prepared by mixing additives, methanol, and toluene; wherein the additives are prepared from raw materials such as co-solvents, dispersants, and modifiers, characterized in that:

[0108] The co-solvent includes propylene glycol methyl ethyl ether, dioxane, and benzyl alcohol, with a volume ratio of propylene glycol methyl ethyl ether, dioxane, and benzyl alcohol of 1:1:1.

[0109] The dispersant is an ethylene glycol-succinic acid oligomer reaction mixture obtained by rapid esterification reaction of ethylene glycol and succinic acid, mainly consisting of oligomers with 2 to 4 polymer units, as well as unreacted ethylene glycol and butyric acid.

[0110] The modifier includes a metal corrosion inhibitor; the metal corrosion inhibitor is prepared by dissolving one or more of cyclohexylamine, aniline and benzo[a]azole in a small amount of methanol.

[0111] The cosolvent, dispersant and modifier are mixed in a ratio of 4:2:0.2 and then subjected to ultrasonic treatment. The ultrasonic dispersion time is 15 min and the ultrasonic power is 600 W.

[0112] 2. The alcohol-based fuel is characterized in that the methanol content in the alcohol-based fuel is 92% by mass; the remaining components are prepared according to the mass ratio of additives, methanol and toluene of 2:92:5.

[0113] 3. A method for preparing alcohol-based fuels, comprising the following steps:

[0114] A) The additive is obtained by mixing, ultrasonically dispersing, and mixing and dispersing the cosolvent, dispersant, and modifier.

[0115] B) Mix the additive, gasoline and methanol, stir for a period of time and then ultrasonically disperse to obtain alcohol-based fuel. The ultrasonic dispersion time is 30 min and the ultrasonic power is 500 W.

[0116] 4. The alcohol-based fuel is characterized by the following reaction conditions for the preparation of the dispersant:

[0117] Oligopolymerization was carried out in a reactor equipped with a water separator and a reflux condenser. Toluene was added to the water separator and nitrogen was introduced as a stirring gas to accelerate the dehydration process.

[0118] According to the molar ratio of ethylene glycol:n(succinic acid) = 1.1:1.0, the raw materials are weighed and added to the reactor. Then, p-toluenesulfonic acid is added to the reactor at a rate of 0.5% of the mass of succinic acid. The reaction temperature is controlled at 170℃ and the reaction time is controlled at 4 hours.

[0119] After the reaction time is up, heating is stopped, and the reaction mixture is washed with water to remove residual catalyst, yielding a dispersant.

[0120] Comparative Example 1

[0121] Methanol and toluene were mixed at a mass ratio of 95:5, stirred for 10 minutes, and then ultrasonically dispersed for 20 minutes to obtain a comparative fuel.

[0122] Comparative Example 2

[0123] Methanol, ethylene glycol methyl ether, and toluene were mixed at a mass ratio of 95:2:3, stirred for 10 minutes, and then ultrasonically dispersed for 20 minutes to obtain the comparative fuel.

[0124] Comparative Example 3

[0125] Methanol, dioxane, and toluene were mixed at a mass ratio of 95:2:3, stirred for 10 minutes, and then ultrasonically dispersed for 20 minutes to obtain a comparative fuel.

[0126] Comparative Example 4

[0127] The methanol, ethylene glycol-succinic acid oligomer reaction mixture and toluene were mixed at a mass ratio of 95:2:3, stirred for 10 min, and then ultrasonically dispersed for 20 min to obtain the control fuel.

[0128] The performance of the alcohol-based fuels in Examples 1-4 was compared and analyzed with that of gasoline and methanol. The results are shown in Table 1.

[0129] Table 1. Performance comparison results of fuels in Examples 1-4 with gasoline, methanol, and palm gasoline.

[0130]

[0131] As shown in Table 1, the oxygen content of the alcohol-based fuel proposed in this invention is significantly higher than that of conventional gasoline. This higher oxygen content effectively improves the overall oxygen level of the gasoline fuel. The oxygen in the fuel helps improve combustion efficiency within the engine and promotes the complete oxidation of nitrogen oxides, thereby effectively reducing carbon monoxide emissions. Furthermore, methanol has a high latent heat of vaporization, which helps lower the combustion chamber temperature, further reducing nitrogen oxide formation. Therefore, the alcohol-based fuel proposed in this invention exhibits significant advantages in emission control.

[0132] The fuel density results show that the alcohol-based fuel used in this invention has a density similar to gasoline and much higher than pure methanol. This characteristic allows for more fuel to be loaded into the same volume of fuel tank, thereby increasing the vehicle's range.

[0133] To evaluate the stability of various fuels in the embodiments and comparative examples of this invention, each fuel sample was vigorously shaken for 5 minutes, and its stratification state before shaking, after shaking, and after standing for 50 hours was observed. The experimental results are detailed in Table 2. Simultaneously, this study also systematically analyzed the stability time and particle size of the fuels in Examples 1 to 4 and Comparative Examples 1 to 5 in the dispersed state. Particle size was determined using a laser particle size analyzer. The specific operating procedure is as follows: After thoroughly shaking the samples from each embodiment and comparative example, they were injected into the sample cell. The "Measurement-Start" function was selected, and the operation procedure was completed according to the software prompts. Then, the sample cell was placed in the instrument, and after the temperature stabilized, "Start" was clicked to perform the measurement. Each group of samples was measured three times, and the final result was the average of the three measurements. The experimental results are detailed in Table 2.

[0134] This invention significantly improves the stability of alcohol-based fuels and effectively enhances their water resistance by introducing a specific moderately polar co-solvent and dispersant system. Even when in contact with water or absorbing a certain amount of moisture, the alcohol-based fuels of this invention remain clear and transparent, without emulsification or stratification, exhibiting excellent physical stability.

[0135] To further verify the stability of the fuel of this invention, 0.1% water was added to both the application example and the control example, and mechanical stirring was performed for 5 minutes, followed by standing for 30 minutes to observe whether stratification occurred. The experimental results are shown in Table 2.

[0136] Table 2 clearly shows that untreated methanol gasoline exhibits poor stability after mixing and readily separates into layers upon contact with water. However, the formulation system proposed in this invention, combined with the effects of various dispersants and co-solvents, allows methanol and toluene to form a more stable dispersion system, resulting in alcohol-based gasoline with a longer stability time. A significant correlation exists between stability time and particle size; formulations with longer stability have smaller particle sizes. The particle sizes in the embodiments of this invention are all smaller than those in the comparative examples, and they remain homogeneous even after the addition of trace amounts of water. Therefore, the alcohol-based gasoline prepared by this invention possesses advantages such as long stability time, small particle size, and strong water resistance. The added co-solvents and dispersants play a crucial role in improving fuel stability.

[0137] Table 2 Comparison of properties of alcohol-based fuels in application examples and comparative examples.

[0138]

[0139] The descriptions of the above embodiments are merely illustrative of the methods and core ideas of the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An alcohol-based fuel for automobiles, characterized in that, It is prepared by mixing additives, methanol, and toluene; the additives are prepared from raw materials such as cosolvents, dispersants, and modifiers, characterized in that: The co-solvent includes at least one of ethylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ether, propylene glycol methyl ethyl ether, dioxane, and benzyl alcohol; wherein the volume ratio of ethylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ether, dioxane, and benzyl alcohol is 0-1:0-1:0-1:0-1:0-1:0-1; The dispersant is an ethylene glycol-succinic acid oligomer reaction mixture obtained by rapid esterification reaction of ethylene glycol and succinic acid, mainly consisting of oligomers with 2 to 4 polymer units, as well as unreacted ethylene glycol and butyric acid. The modifier is a metal corrosion inhibitor, which is one or more of cyclohexylamine, aniline and benzo[a]azole dissolved in a small amount of methanol; The cosolvent, dispersant and modifier are mixed in a ratio of 1-10:1-5:0.1-2 and then subjected to ultrasonic treatment. The ultrasonic dispersion time is 8-15 min and the ultrasonic power is 500-600 W. The alcohol-based fuel is characterized in that the mass content of methanol in the fuel is 90-95%; and its components are prepared according to the mass ratio of additives, methanol and toluene of 0.5-10:85-95:5-15.

2. The preparation method of the alcohol-based fuel according to claim 1 includes the following steps: A) The additive is obtained by mixing, ultrasonically dispersing, and mixing and dispersing the cosolvent, dispersant, and modifier. B) Mix the additives, toluene and methanol, stir for a period of time and then ultrasonically disperse to obtain alcohol-based fuel. The ultrasonic dispersion time is 15-30 min and the ultrasonic power is 500-600 W.

3. The alcohol-based fuel according to claim 1, characterized in that, The reaction conditions for preparing the dispersant are as follows: Oligopolymerization was carried out in a reactor equipped with a water separator and a reflux condenser. Toluene was added to the water separator and nitrogen was introduced as a stirring gas. Weigh the raw materials and add them to the reactor according to the molar ratio of n(ethylene glycol):n(succinic acid) = 1.1:1.0 to 1.5:1.

0. Then add p-toluenesulfonic acid to the reactor in an amount of 0.5% to 2% of the mass of succinic acid. Control the reaction temperature at 160℃-190℃ and the reaction time at 1 to 4 hours. After the reaction time is up, heating is stopped, and the reaction mixture is then washed with water to remove residual catalyst, yielding a dispersant.

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