Alcohol-based diesel fuel and preparation method thereof

Abstract

The invention relates to the technical field of petrochemical fuel substitution, in particular to clear and transparent medium-proportion alcohol-based diesel fuel and a preparation method thereof.The alcohol-based diesel fuel is prepared from methanol, diesel and additives, and the mass content of methanol is within the range of 60%-70%. Under the action of the additive, the methanol, the diesel oil and the additive are fully dispersed and uniformly mixed by jointly using ultrasonic and high-speed shearing methods to form the stable alcohol-based diesel oil fuel, and the prepared alcohol-based diesel oil fuel has the advantages of being clear, transparent, small in dispersion particle size and long in stabilization time.

Description

Technical Field

[0001] The invention relates to the technical field of alcohol-based diesel fuels, and in particular to a medium-proportion alcohol-based diesel fuel with good stability and a preparation method thereof. Background Art

[0002] With the rapid development of my country's economy and the shortage of oil resources in the world, energy substitution has become a strategic goal for countries around the world. Coal-based methanol has the advantages of abundant raw materials, mature technology and low production cost. Coal-based methanol fuel has become an alternative engine fuel suitable for my country's national conditions due to its good combustion characteristics, abundant raw material sources, mature technology and considerable scale of basic production facilities.

[0003] Alcohol fuel is an internationally recognized petroleum substitute fuel. Relevant departments believe that the use of methanol fuel is the most effective way to achieve a stable environment. Moreover, 10% to 30% and 80% to 90% partial substitution reduces the cost of fuel by about 10% to 20% and 50% to 80%, respectively, which has significant economic benefits and broad application prospects.

[0004] Compared with coal, gasoline and diesel, methanol has the characteristics of a single molecular formula and a simple structure. Its combustion emissions are very stable, and there is no emission of pollutants such as particulate matter (PM2.5, PM10), ozone, sulfur dioxide, CO, mercury and its compounds. The new alcohol ether fuel will be able to replace coal, gasoline and diesel, alleviate air pollution, and fit the main characteristics of my country's energy structure. Therefore, methanol, as an important derivative product of coal chemical industry, is currently recognized as one of the most promising alternative fuels. Due to the stability and wide sources of methanol, as a gasoline engine alternative fuel, it has the characteristics of high octane number, low pollution and no smoke. It can be used alone or mixed with gasoline in the ignition engine, and the engine's power, economy and emission reduction effect are significantly improved. The annual consumption of gasoline is far greater than that of methanol. If methanol gasoline can be promoted like gasoline, it will definitely play a vital role in energy conservation and national energy strategy. Methanol has been tried and promoted in many western provinces as a gasoline locomotive alternative fuel, which has positive significance for my country's implementation of energy diversification and energy substitution strategies.

[0005] Compared with methanol gasoline fuel, methanol diesel fuel has greater difficulties. The compatibility of methanol and diesel is limited by many conditions such as dispersion particle size, molecular polarity, stability, etc. They are not miscible, especially when they meet water, they will emulsify and then quickly stratify. Methanol (CH3OH) is an oxygen-containing hydrocarbon containing polar hydroxyl (OH) and is a highly polar substance. Gasoline is a mixture of various hydrocarbons or non-hydrocarbons, and hydrocarbon compounds are non-polar molecules. According to the principle of like dissolves like, methanol and gasoline cannot be completely mixed. At room temperature, about 3-5% of methanol can be dissolved in diesel. When the methanol content exceeds 5%, methanol and diesel are difficult to mix evenly to form a stable emulsion. At present, many researchers are actively developing an additive that can make methanol and diesel mix better, but no additive has been successfully developed, which has prevented alcohol-based diesel from being widely used.

[0006] It is known from the prior art that in the preparation process of alcohol-based diesel fuel, the alcohol-based diesel has poor dispersibility and short stability time due to the large difference in polarity between methanol and diesel. Among the currently disclosed alcohol-based diesel fuel preparation technologies, most of the research focuses on alcohol-based diesel fuel with methanol substitution rates of 10% to 30% and 80% to 90%. Since the medium-proportion methanol substitution fuel (40% to 80%) is more difficult to disperse and has poorer stability, it has higher requirements for the composition, additives and dispersion methods of alcohol-based fuels. There are few studies on the methanol substitution rate within the range of 60% to 70%. Therefore, it is more important to carry out research on the dispersion method and additives of alcohol-based diesel with a methanol substitution rate of 60% to 70%. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a clear and transparent medium-proportion alcohol-based diesel fuel and a preparation method thereof. The alcohol-based fuel uses methanol, diesel and additives as raw materials, and under the action of additives such as cosolvents, dispersants and modifiers, ultrasonic and high-speed shearing methods are combined to fully crush and uniformly mix methanol, diesel and additives through vibration, cavitation effect, mechanical shear force, turbulence effect and cavitation effect to form a stable alcohol-based fuel system. The alcohol-based diesel fuel provided by the present invention has the characteristics of clarity, small dispersed particle size and long stability time.

[0008] (1) The present invention provides a medium-proportion alcohol-based diesel fuel, wherein the mass ratio of methanol: diesel: additive is 60-80:5-20:5-20, and the methanol mass content is controlled within the range of 60%-70%; the additive is prepared from a cosolvent, a dispersant, and a modifier, and its methanol content is more stringent than that of the prior art, and a 60%-70% methanol substitution rate provides higher requirements for dispersion stability. The additive of the present invention can solve the stability of alcohol-based diesel with a medium methanol content.

[0009] (2) wherein the co-solvent comprises at least one or more of propylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ethyl ether and butanol; wherein the volume ratio of propylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ethyl ether and butanol is 1-10:1-10:1-10:1-20.

[0010] (3) The dispersant comprises at least one of oleic acid, OP10, octylphenol polyoxyethylene ether, Span80, Span60, Tween80 and Tween60; the mass ratio of oleic acid, OP10, octylphenol polyoxyethylene ether, Span80, Span60, Tween80 and Tween60 is 0-10:0-10:0-10:0-10:0-10:0-10:0-10.

[0011] (4) wherein the modifier comprises a metal corrosion inhibitor; the metal corrosion inhibitor is one of cyclohexylamine, aniline and benzazolidine.

[0012] (5) In the process of preparing the additive, the mass ratio of the cosolvent, dispersant and modifier is 1-100:0.1-50:0.1.

[0013] (6) A method for preparing an alcohol-based diesel fuel, comprising the following steps:

[0014] A) dispersing diesel, a cosolvent and a modifier with the assistance of ultrasound to obtain a composite diesel component a;

[0015] The dispersant and methanol are mixed and dispersed with ultrasound assistance to obtain functional component b;

[0016] B) The composite diesel component a and the functional component b are mixed, stirred for a period of time, dispersed with ultrasound assistance, and then sheared and dispersed in a high-speed shearing machine to obtain a medium-proportion alcohol-based diesel fuel.

[0017] (7) In the above step A), the ultrasonic dispersion time in the preparation of the composite diesel component a is 8 to 15 minutes, and the ultrasonic power is 500 to 600 W;

[0018] The ultrasonic assisted dispersion time in the preparation of functional component b is 8 to 15 minutes, and the ultrasonic power is 500 to 600 W;

[0019] In the above step B), the ultrasonic assisted dispersion time is 18 to 25 minutes, and the ultrasonic power is 500 to 600 W;

[0020] In the above step B), the high-speed shear rate is 6000-10000 r / s, and the shear time is 3-10 min.

[0021] Creativity of the present invention

[0022] The present invention utilizes ultrasonic treatment and high-speed shear emulsification to jointly treat a medium-proportion alcohol-based diesel fuel system to form a fuel system with high dispersion and long stability time. Ultrasound and high-speed shearing jointly exert high-speed mechanical shear force, turbulence effect, cavitation effect, vibration, cavitation effect and emulsification effect, and these effects occur in combination, which is of great significance for promoting the nano-scale dispersion of medium-proportion methanol, diesel and additives. The specific dispersion principle of the technology of the present invention includes:

[0023] (1) High-speed mechanical shear force

[0024] The rotor in the equipment rotates at high speed, generating strong shearing force. Then the narrow gap between the rotor and the stator causes the material to be strongly sheared, and large particles are broken into tiny particles.

[0025] (2) Turbulence effect

[0026] High-speed rotation generates eddy currents, which increase the collision and friction between materials. The turbulence makes different components fully mixed to form a stable emulsified system.

[0027] (3) Hole effect

[0028] High-speed rotation causes local pressure changes, producing a cavitation effect. Bubble collapse: When cavitation bubbles collapse, shock waves are generated, further breaking up the particles.

[0029] (4) Emulsification

[0030] In alcohol-based diesel fuel systems, cosolvents and dispersants contain emulsifiers, which reduce interfacial tension and help form stable emulsions.

[0031] Under the action of co-solvents, dispersants and modifiers, combined with ultrasound and high-speed shearing, methanol, diesel and additives are fully crushed and evenly mixed through mechanical shear force, turbulence effect and cavitation effect to form a stable, clear and transparent alcohol-based fuel system.

[0032] Specific embodiments of the present invention

[0033] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solution of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In an embodiment of the present invention, the co-solvent can be obtained by stirring and mixing at least one of propylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ethyl ether and butanol.

[0035] In some embodiments, the cosolvent includes propylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ethyl ether and butanol in a volume ratio of 1:1 to 2:1 to 2:1 to 20. In some embodiments, the volume ratio of propylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ethyl ether and butanol is 1:1:1:10, 1:2:1:20 or 1:2:1:15.

[0036] In some embodiments of the present invention, the dispersant includes at least one of oleic acid, OP10, octylphenol polyoxyethylene ether, Span80, Span60, Tween80 and Tween60; the mass ratio of oleic acid, OP10, octylphenol polyoxyethylene ether, Span80, Span60, Tween80 and Tween60 is 0-10:0-10:0-10:0-10:0-10:0-10:0-10. In some embodiments of the present invention, the dispersant can be obtained by stirring and mixing oleic acid, OP10, octylphenol polyoxyethylene ether, Span80, Span60, Tween80 and Tween60.

[0037] In some embodiments, the dispersant comprises oleic acid, Span 80 and Tween 80 in a mass ratio of 10 to 15: 2 to 5: 1. In some embodiments, the dispersant comprises oleic acid, Span 80 and Tween 80 in a mass ratio of 15: 5: 1, 10: 2: 1, 14: 5: 1 or 10: 2: 1.

[0038] In certain embodiments of the present invention, the modifier includes a metal corrosion inhibitor, which is prepared by dissolving one or more of cyclohexylamine, aniline and benzazole in a small amount of methanol.

[0039] In the process of preparing the additive, the mass ratio of the cosolvent, the dispersant and the modifier is 1-100:0.1-50:0.1.

[0040] The present invention has no particular restrictions on the type and source of the diesel, and commercially available petrochemical refined diesel can be used. In certain embodiments of the present invention, the diesel is selected from Qingdao Refining and Chemical Hydrogenated Diesel or Jingbo Petrochemical Finished Diesel.

[0041] In certain embodiments of the present invention, the mass ratio of the cosolvent, dispersant, and modifier is 1-10:5-20:0.1. The mass ratio of methanol: diesel: additive is 60-80:5-20:5-20, and the methanol mass content is controlled at 60%-70%. In certain embodiments, the mass ratio of the cosolvent, dispersant, and modifier is 5:5:0.1, 5:10:0.1, 10:15:0.1, or 2:5:0.1. The mass ratio of methanol: diesel: additive is 60:20:20, 70:20:20, 70:15:20, or 65:20:15.

[0042] The alcohol-based diesel fuel provided by the present invention has a relatively high oxygen content of about 12 to 70 wt%.

[0043] The present invention also provides a method for preparing an alcohol-based diesel fuel, comprising the following steps:

[0044] A) mixing diesel, a cosolvent and a modifier, and performing ultrasonic dispersion to obtain a composite diesel component a;

[0045] The dispersant and methanol are mixed and ultrasonically dispersed to obtain a functional component b;

[0046] B) The composite diesel component a and the functional component b are mixed, stirred for a period of time, ultrasonically dispersed, and then sheared and dispersed in a high-speed shearing machine to obtain an alcohol-based diesel fuel.

[0047] The invention mixes composite diesel component a and functional component b, fully stirs to prevent methanol from precipitating and stratifying, and then ultrasonically disperses methanol, cosolvent, dispersant and modifier to fully disperse and form a stable system to obtain alcohol-based diesel fuel.

[0048] In the method for preparing the alcohol-based diesel fuel provided by the present invention, the raw material components and proportions used are the same as above and will not be described in detail herein.

[0049] In step A):

[0050] In certain embodiments of the present invention, the ultrasonic dispersion time in preparing the composite diesel component a is 8 to 15 minutes, and the ultrasonic power is 500 to 600 W. In certain embodiments, the ultrasonic dispersion time in preparing the composite diesel component a is 10 minutes, and the ultrasonic power is 550 W.

[0051] In certain embodiments of the present invention, the ultrasonic dispersion time in the preparation of functional component b is 8 to 15 minutes, and the ultrasonic power is 500 to 600 W. In certain embodiments, the ultrasonic dispersion time in the preparation of functional component b is 10 minutes, and the ultrasonic power is 550 W.

[0052] In step B):

[0053] In some embodiments of the present invention, the stirring time is 8 to 15 minutes. In some embodiments, the stirring time is 8 to 10 minutes.

[0054] In certain embodiments of the present invention, the ultrasonic dispersion time is 18 to 25 minutes, and the ultrasonic power is 500 to 600 W. In certain embodiments, the ultrasonic dispersion time is 20 minutes, and the ultrasonic power is 550 W;

[0055] In step B), the high-speed shear rate is 6000-10000 r / s, and the shear time is 3-10 min.

[0056] The alcohol-based diesel fuel provided by the invention has a methanol content in the range of 60-80wt%, a high oxygen content, a long stability time, and can be stably burned during use.

[0057] The alcohol-based diesel fuel provided by the present invention does not contain metal additives, and the additives with a sulfur content of less than 10 μg / g in the fuel are mainly oxygen-containing compounds, of which methanol is the main additive. Since methanol has the advantages of wide sources, low cost and low toxicity, the fuel provided by the present invention is a clean alcohol-based diesel fuel. The diesel component is obtained by compounding the diesel containing multiple polar components with diesel, and under the action of the dispersant and the cosolvent, an alcohol-based diesel fuel with a small dispersed particle size and a long stable time can be formed. In addition, the preparation method provided by the present invention is simple to operate.

[0058] In order to further illustrate the present invention, an alcohol-based diesel fuel and a preparation method thereof provided by the present invention are described in detail below in conjunction with examples, but it should not be construed as limiting the scope of protection of the present invention.

[0059] Example 1

[0060] 1) In a container equipped with a stirrer, add propylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ethyl ether and butanol.

[0061] 2) Propylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ethyl ether and butanol are mixed in a volume ratio of 1:1:1:10, and stirred evenly to obtain a cosolvent.

[0062] 3) Oleic acid, Span 80 and Tween 80 were mixed in a mass ratio of 15:5:4 and stirred evenly to obtain a dispersant.

[0063] 4) The benzazolidine metal corrosion inhibitor is dissolved in a small amount of methanol to prepare a modifier.

[0064] 5) The mass ratio of the cosolvent, dispersant and modifier is 5:5:0.1, and the mass ratio of methanol:diesel:additive is 60:20:20.

[0065] 6) The corresponding parts by weight of diesel, co-solvent and modifier are mixed and ultrasonically dispersed for 10 minutes at an ultrasonic power of 550 W to obtain a composite diesel component a.

[0066] 7) After mixing corresponding weight portions of dispersant and methanol, ultrasonic dispersion was performed for 10 minutes at an ultrasonic power of 550 W to obtain functional component b.

[0067] 8) The composite diesel component a and the functional component b are mixed, stirred for 10 minutes, ultrasonically dispersed for 20 minutes, the ultrasonic power is 550 W, and sheared and dispersed in a high-speed shearing machine at a high-speed shear rate of 6000 r / s and a shearing time of 10 minutes to obtain a medium-proportion alcohol-based diesel fuel.

[0068] Example 2

[0069] 1) In a container equipped with a stirrer, add propylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ethyl ether and butanol.

[0070] 2) Propylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ethyl ether and butanol are mixed in a volume ratio of 1:2:1:10, and stirred evenly to obtain a cosolvent.

[0071] 3) Span 80 and Tween 80 are mixed in a mass ratio of 2:4 and stirred evenly to obtain a dispersant.

[0072] 4) Dissolve the benzazolidine metal corrosion inhibitor in a small amount of methanol to prepare a modifier.

[0073] 5) The mass ratio of the cosolvent, dispersant and modifier is 5:10:0.1, and the mass ratio of methanol:diesel:additive is 70:20:20. 6) The corresponding weight parts of diesel and parts of cosolvent and modifier are mixed and ultrasonically dispersed for 10 minutes at an ultrasonic power of 550W to obtain a composite diesel component a.

[0074] 7) After mixing corresponding weight portions of dispersant and methanol, ultrasonic dispersion was performed for 10 minutes at an ultrasonic power of 550 W to obtain functional component b.

[0075] 8) The composite diesel component a and the functional component b are mixed, stirred for 10 minutes, ultrasonically dispersed for 20 minutes, the ultrasonic power is 550 W, and sheared and dispersed in a high-speed shearing machine at a high-speed shear rate of 8000 r / s and a shearing time of 8 minutes to obtain a medium-proportion alcohol-based diesel fuel.

[0076] Example 3

[0077] 1) In a container equipped with a stirrer, add propylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ethyl ether and butanol.

[0078] 2) Propylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ethyl ether and butanol are mixed in a volume ratio of 1:1:2:16, and stirred evenly to obtain a cosolvent.

[0079] 3) Oleic acid, Span 80 and Tween 80 were mixed in a mass ratio of 14:5:1 and stirred evenly to obtain a dispersant.

[0080] 4) Dissolve the aniline metal corrosion inhibitor in a small amount of methanol to prepare the modifier.

[0081] 5) The mass ratio of the cosolvent, dispersant and modifier is 10:15:0.1, and the mass ratio of methanol:diesel:additive is 70:15:20.

[0082] 6) 10 parts by weight of diesel fuel, 7 parts by weight of cosolvent and 0.1 parts by weight of modifier were mixed, and ultrasonic dispersion was performed for 10 minutes at an ultrasonic power of 550 W to obtain a composite diesel fuel component a.

[0083] 7) After mixing 1 part by weight of the dispersant with 70 parts by weight of methanol, the mixture was dispersed by ultrasound for 10 minutes at an ultrasonic power of 550 W to obtain functional component b.

[0084] 8) The composite diesel component a and the functional component b are mixed, stirred for 10 minutes, ultrasonically dispersed for 20 minutes, the ultrasonic power is 550 W, and sheared and dispersed in a high-speed shearing machine at a high-speed shear rate of 7000 r / s and a shearing time of 7 minutes to obtain a medium-proportion alcohol-based diesel fuel.

[0085] Example 4

[0086] 1) In a container equipped with a stirrer, add propylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ethyl ether and butanol.

[0087] 2) Propylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ethyl ether and butanol are mixed in a volume ratio of 1:2:2:12, and stirred evenly to obtain a cosolvent.

[0088] 3) Oleic acid, Span 80 and Tween 80 were mixed in a mass ratio of 10:2:2 and stirred evenly to obtain a dispersant.

[0089] 4) Dissolve the aniline metal corrosion inhibitor in a small amount of methanol to prepare the modifier.

[0090] 5) The mass ratio of the cosolvent, dispersant and modifier is 2:5:0.1, and the mass ratio of methanol:diesel:additive is 65:20:15.

[0091] 6) After mixing corresponding weight portions of diesel, co-solvent and modifier, ultrasonic dispersion was performed for 10 minutes at an ultrasonic power of 550 W to obtain a composite diesel component a.

[0092] 7) After mixing corresponding weight portions of dispersant and methanol, ultrasonic dispersion was performed for 10 minutes at an ultrasonic power of 550 W to obtain functional component b.

[0093] 8) The composite diesel component a and the functional component b are mixed, stirred for 10 minutes, ultrasonically dispersed for 20 minutes, the ultrasonic power is 550 W, and sheared and dispersed in a high-speed shearing machine at a high-speed shear rate of 7000 r / s and a shearing time of 5 minutes to obtain a medium-proportion alcohol-based diesel fuel.

[0094] Comparative Example 1

[0095] Methanol and diesel were mixed in a mass ratio of 65:35, stirred for 10 minutes, and then ultrasonically dispersed for 20 minutes to obtain a comparison fuel.

[0096] Comparative Example 2

[0097] Methanol, ethylene glycol methyl ether and diesel were mixed in a mass ratio of 65:3:32, stirred for 10 minutes, and then ultrasonically dispersed for 20 minutes to obtain a comparison fuel.

[0098] Comparative Example 3

[0099] Methanol, butanol and diesel were mixed in a mass ratio of 65:2:33, stirred for 10 minutes, and then ultrasonically dispersed for 20 minutes to obtain a comparison fuel.

[0100] Comparative Example 4

[0101] Oleic acid, Span80 and Tween80 are mixed in a mass ratio of 10:2:2, and stirred evenly to obtain a dispersant; methanol and diesel are mixed in a mass ratio of 65:30 to obtain alcohol-based diesel; then the dispersant is added to the alcohol-based diesel, and the amount of the dispersant added accounts for 5% of the mass of the alcohol-based diesel; after all components are mixed, they are stirred for 10 minutes, ultrasonically dispersed for 20 minutes, and sheared and dispersed in a high-speed shearing machine at a high-speed shear rate of 6000 r / s and a shear time of 10 minutes to obtain a comparison fuel.

[0102] The performance of the alcohol-based fuels in Examples 1 to 4 was compared with that of diesel and methanol, and the results are shown in Table 1.

[0103] Table 1 Performance comparison results of medium-proportion alcohol-based diesel fuel of Examples 1 to 4, diesel and methanol

[0104]

[0105] As can be seen from Table 1, the oxygen content of the medium-proportion alcohol-based fuel of the present invention is significantly higher than that of diesel, which significantly increases the oxygen content of diesel. The oxygen-containing diesel fuel is conducive to combustion in the engine and complete oxidation of nitrogen oxides, reducing CO emissions. At the same time, methanol has a large latent heat of vaporization, which is conducive to reducing cylinder temperature and reducing NOx emissions. The oxygen-containing alcohol-based diesel fuel of the present invention has the advantage of significant clean emissions.

[0106] In terms of density, the fuel of the present invention is close to the density of diesel and much higher than that of methanol, so that a motor vehicle tank of the same volume can carry more fuel and increase the cruising range of the motor vehicle.

[0107] The various fuels of the embodiments of the present invention and the comparative examples were shaken for 2 minutes, and the fuel stratification was observed before, after and after standing for 12 hours. The results are shown in Table 2.

[0108] At the same time, this example also examines the stability time and dispersion particle size of the alcohol-based diesel fuel in Examples 1 to 4 and the fuel in Comparative Examples 1 to 5 after dispersion. The dispersion particle size was measured using a laser particle size analyzer. The method is as follows: Shake the prepared comparative example and example samples evenly and inject them into the sample pool, then select MeasureStart and follow the steps of the software. Then insert the sample pool into the instrument, wait for the temperature to balance, click Start to measure, and measure three times to take the average value. The experimental results are shown in Table 2.

[0109] The invention adopts a special cosolvent and a dispersant, which can significantly improve the stability of the medium-proportion alcohol-based fuel and can significantly improve the water stability of the alcohol-based fuel. After mixing or absorbing part of water, the medium-proportion alcohol-based fuel of the invention remains clear and transparent, does not emulsify, does not stratify, and has good stability.

[0110] In order to investigate the stability of the alcohol-based fuel of the present invention, 0.1% water was added to the application examples and comparative examples, mechanically stirred for 5 minutes, and then the stratification of the fuel was observed after standing for 30 minutes. The experimental results are shown in Table 2.

[0111] As can be seen from Table 2, alcohol-based diesel is unstable after direct mixing and is easy to stratify after encountering water. Using the formula of the present invention, under the action of various dispersants and cosolvents, methanol and diesel form a more stable dispersed diesel system, and a longer stable alcohol-based diesel is obtained. The stable time is basically related to the dispersed particle size, and the dispersed particle size of the formula with a long stable time is smaller. The dispersed particle size of the embodiments of the present invention is smaller than the dispersed particle size of the comparative example. After adding a small amount of water, it still remains unstratified. Therefore, the alcohol-based diesel prepared by the present invention has the advantages of long stable time, small dispersed particle size and water resistance. The added cosolvent and surfactant have a significant improvement effect on the stability of alcohol-based diesel fuel.

[0112] Table 2 Comparison of properties of the medium-proportion alcohol-based diesel fuel application examples and comparative examples of the present invention

[0113]

[0114] The description of the above embodiments is only used to help understand the method of the present invention and its core idea. Various modifications of these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. The present invention provides a medium-proportion alcohol-based diesel fuel, which uses methanol, diesel and additives as raw materials. Under the action of the additives, the methanol, diesel and additives are fully dispersed and uniformly mixed by combining ultrasonic and high-speed shearing methods to form a stable, clear and transparent medium-proportion alcohol-based diesel fuel; Of which methanol: The mass ratio of diesel: additive is 60-80:5-20:5-20, and the mass content of methanol is controlled within the range of 60%-70%; the additive is prepared from a cosolvent, a dispersant, and a modifier; wherein the cosolvent comprises at least one or more of propylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ethyl ether and butanol; the volume ratio of propylene glycol methyl ether, ethylene glycol methyl ethyl ether, propylene glycol methyl ethyl ether and butanol is 1-10:1-10:1-10:1-20; wherein the The dispersant comprises at least one of oleic acid, OP10, octylphenol polyoxyethylene ether, Span80, Span60, Tween80 and Tween60; the mass ratio of oleic acid, OP10, octylphenol polyoxyethylene ether, Span80, Span60, Tween80 and Tween60 is 0-10:0-10:0-10:0-10:0-10:0-10:0-10; wherein the modifier is a metal corrosion inhibitor; The metal corrosion inhibitor is one of cyclohexylamine, aniline and benzazolidine; the mass ratio of the cosolvent, the dispersant and the modifier is 1-100:0.1-50:0.

1.

2. The method for preparing a medium-proportion alcohol-based diesel fuel according to claim 1, comprising the following steps: 1) Diesel, a cosolvent and a modifier are dispersed with the assistance of ultrasound to obtain a composite diesel component a; the dispersant and methanol are mixed and dispersed with the assistance of ultrasound to obtain a functional component b; 2) mixing the composite diesel component a and the functional component b, stirring and then dispersing by ultrasonic assistance, and then shearing and dispersing in a high-speed shearing machine to obtain a medium-proportion alcohol-based diesel fuel; Wherein in step 1), the ultrasonic assisted dispersion time for preparing the composite diesel component a is 8 to 15 minutes, and the ultrasonic power is 500 to 600 W; the ultrasonic assisted dispersion time for preparing the functional component b is 8 to 15 minutes, and the ultrasonic power is 500 to 600 W; in step 2), the ultrasonic assisted dispersion time is 18 to 25 minutes, and the ultrasonic power is 500 to 600 W; in step 2), the high-speed shear rate is 6000 to 10000 r / s, and the shear time is 3 to 10 minutes.

Images