CN114806651A

CN114806651A - Modified alcohol-based composite environment-friendly fuel

Info

Publication number: CN114806651A
Application number: CN202210511746.3A
Authority: CN
Inventors: 陈记; 路新龙
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-05-12
Filing date: 2022-05-12
Publication date: 2022-07-29
Anticipated expiration: 2042-05-12
Also published as: CN114806651B

Abstract

The invention provides a modified alcohol-based composite environment-friendly fuel with better dynamic performance and fuel economy; when the alcohol-based fuel is used for a gasoline engine with direct injection in a cylinder, the problems of carbon deposition, particulate matter generation and the like in the cylinder are obviously improved, the maintenance requirement and the maintenance cost of the engine are reduced, and when the exhaust system is provided with the particulate trap, the particulate trap needing special carbon burning regeneration is basically not blocked due to the alcohol-based fuel; the adopted atomization combustion control agent is easy to purchase or prepare, and the technical effects of reducing carbon deposition in a cylinder, reducing the generation amount of particulate matters and the like are achieved on the basis of lower addition amount. The modified alcohol-based composite environment-friendly fuel is suitable for direct injection engines and intake manifold multipoint electronic injection engines, comprises a self-absorption gasoline engine with exhaust gas turbocharging and/or a gasoline engine with an accurate valve control technology, particularly a gasoline engine with low discharge capacity of less than 1.6L, and has a good market prospect.

Description

Modified alcohol-based composite environment-friendly fuel

Technical Field

The invention belongs to the technical field of clean fuel oil, and particularly relates to a modified alcohol-based composite environment-friendly fuel.

Background

At present, the fuel supply mode of the gasoline engine for the vehicle mainly comprises multi-point electric injection of an intake manifold and direct injection in a cylinder.

Compared with multipoint electric injection, the in-cylinder direct injection technology mainly injects gasoline into the cylinder at a short time before and after ignition of a spark plug, the gasoline is directly mixed with air in the cylinder, the control and matching of the oil injection time, the oil injection quantity and the ignition time are accurate and flexible, layered combustion and thin combustion with higher power efficiency and thermal efficiency are realized under the conditions of high air-fuel ratio and high compression ratio, and the matching and the effect with complex gas distribution conditions are easily realized, so that the fuel consumption is reduced while the power performance of an engine, such as the power per liter and the maximum torque, particularly the low-speed torque, is obviously improved, and the application is increased day by day. The engine and the exhaust gas turbocharging technology are effectively combined, the high power performance and the fuel economy of the engine are well realized, and therefore the installed ratio of the low-displacement gasoline engine adopting the in-cylinder direct injection technology is higher and higher. However, the defects of easy carbon deposition, high particulate matter generation amount and the like existing in the gasoline engine in-cylinder direct injection technology are still difficult to overcome and are much more serious than those of the gasoline engine in-cylinder direct injection technology, so that the maintenance requirement and the maintenance cost of the engine are higher, particle traps are required to be assembled in exhaust systems of a plurality of engines, and the particle traps generally need carbon burning regeneration; these problems cause a lot of inconvenience and trouble to the vehicle user.

The low-proportion methanol gasoline for vehicles, such as M15 methanol gasoline with proper formula and preparation, can directly replace the conventional gasoline with the same grade, and has certain advantages in the aspects of fuel economy and tail gas emission. However, in the prior art, low-proportion vehicle methanol gasoline such as M15 is developed ten years ago based on the current multipoint electronic injection technology and the engine tail gas emission standard, even if the existing blended component oil meeting the national six gasoline standard is modified, the improvement range of the defects of easy carbon deposition, high particulate matter generation amount and the like of the in-cylinder direct injection technology is limited, the engine maintenance requirement and the maintenance cost are still higher, and the exhaust system still needs special carbon burning regeneration when being provided with the particle catcher; namely, the low-proportion methanol gasoline for vehicles is not suitable for the cylinder direct injection technical engine which is widely used at present, is not suitable for the exhaust gas turbocharging + cylinder direct injection gasoline engine with low displacement, such as less than 1.6L which is widely used at present, and has less obvious advantages in the aspects of fuel economy and engine maintenance compared with the conventional gasoline which adopts the six standards of the state, and the additives are forbidden or difficult to purchase, so that the continuous production and the market acceptance are not easy to achieve.

On the other hand, the main component of the low-proportion vehicle methanol gasoline in the prior art is still gasoline blending component oil, and the problems of high cost, low fuel economy and the like exist under the market condition of enterprises with high crude oil price.

Disclosure of Invention

In order to solve the technical problems, the invention provides the modified alcohol-based composite environment-friendly fuel with better dynamic performance and fuel economy; when the alcohol-based fuel is used for an in-cylinder direct injection gasoline engine, including an in-cylinder direct injection engine with an exhaust gas turbocharging and/or accurate valve control technology, the problems of carbon deposition, particulate matter generation and the like in the cylinder are obviously improved, the engine maintenance requirement and maintenance cost are reduced, and the particle catcher needing special carbon burning regeneration is basically not blocked due to the alcohol-based fuel when an exhaust system is assembled with the particle catcher; compared with the prior art low-proportion vehicle methanol gasoline which meets the six standards of the prior art and has similar methanol content with the same grade, the methanol gasoline has certain advantages; the adopted atomization combustion control agent is easy to purchase or prepare, and the technical effects of reducing carbon deposition in a cylinder, reducing the generation amount of particulate matters and the like are achieved on the basis of lower addition amount. The modified alcohol-based composite environment-friendly fuel can be widely applied to direct injection engines with different discharge capacities, structures and control logics, is more suitable for an intake manifold multipoint electric injection engine with lower requirements on fuel quality and performance conditions, is also suitable for a double-injection technology engine combining intake manifold multipoint electric injection and in-cylinder direct injection, comprises a self-absorption gasoline engine with exhaust gas turbocharging and/or a gasoline engine with an accurate valve control technology, and particularly relates to a gasoline engine with a low discharge capacity of below 1.6L, so that the modified alcohol-based composite environment-friendly fuel has a better market prospect.

The modified alcohol-based composite environment-friendly fuel comprises, by weight, 10-40% of methanol, 5-10% of palm oil, 0.1-0.5% of an atomization combustion control agent, 0.02-0.1% of a metal corrosion inhibitor, 0.02-0.2% of a rubber swelling inhibitor and the balance solvent oil; the sulfur content of the solvent oil is less than or equal to 10mg/kg, and the solvent oil is No. 1-4 solvent oil which meets the regulation of GB 1922-2006; the atomized combustion control agent contains polymethyl phenyl ethanol ((CH) ₃ ) _X -C ₆ H _6-X-1 )-CH ₂ -CH ₂ -OH, polymethylphenyl ethyl ether ((CH) ₃ ) _X -C ₆ H _6-X-1 )-O-CH ₂ -CH ₃ The weight ratio of (A) to (B) is 50-75: 5-15, polymethylphenylethanol + polymethylphenetole ≥ 60wt%, wherein X =2 or 3; when X =2, the polymethylphenyl group is o-dimethylphenyl, i.e., 1, 2-dimethylphenyl, or m-dimethylphenyl, i.e., 1, 3-dimethylphenyl, and when the polymethylphenyl group is o-dimethylphenyl, the-CH group ₂ -CH ₂ -OH or-O-CH ₂ -CH ₃ The bonding position to the benzene ring is 4-position, and when the polymethylphenyl group is m-dimethylphenyl, the-CH ₂ -CH ₂ -OH or-O-CH ₂ -CH ₃ The linking position with the benzene ring is 5-position; when X =3 the polymethylphenyl group is a vicinal trimethylphenyl group, i.e. a 1,2, 3-trimethylphenyl group, or a partial trimethylphenyl group, i.e. a 1,2, 4-trimethylphenyl group, when the-CH group is present ₂ -CH ₂ -OH or-O-CH ₂ -CH ₃ The connecting positions with the benzene ring are all 5 positions.

In the atomized combustion control agent, the weight ratio of the polymethylphenyl ethanol to the polymethylphenyl ethyl ether is preferably 58 to 63: 8.

the atomized combustion control agent can be a mixture of the polymethylphenyl ethanol and the polymethylphenyl ethyl ether, but the two chemicals of the polymethylphenyl ethanol and the polymethylphenyl ethyl ether are low in production amount and high in price at present, and the atomized combustion control agent is not used as a vehicle fuel additive. In order to control the cost and the purchasing difficulty, the polymethylphenyl ethanol and the polymethylphenyl ethyl ether contained in the catalyst can be prepared by taking one or more of o-xylene, m-xylene, hemimellitene and pseudomellitene or aromatic oil containing more than 80wt% of the polymethylbenzene as raw materials of the polymethylphenyl and reacting the raw materials with aromatic oil capable of generating the-CH at the connecting position of phenyl ₂ -CH ₂ -OH、-O-CH ₂ -CH ₃ Such as ethylene oxide, by direct reaction. The components other than the polymethylbenzene in the hydrocarbon oil should not affect the reaction of the polymethylbenzene with ethylene oxide to produce the polymethylphenylethanol and the polymethylphenetole.

The polymethyl benzene or hydrocarbon oil containing more than 80wt% of the polymethyl benzene reacts with ethylene oxide to synthesize the polymethyl phenyl ethanol and the polymethyl phenyl ethyl ether with the weight ratio, and one preparation method comprises the following steps: one or more than one of o-xylene, m-xylene, hemimellitene and unsym-trimethylbenzene or aromatic oil containing more than 80w percent of the polymethylbenzene is uniformly mixed with ethylene oxide according to the required proportion, a powdery Pt/HZSM-5 molecular sieve catalyst is added, the reaction temperature is 30-40 ℃, the reaction is stirred and reacted for 8-20 hours under the condition of liquid phase, the Pt/HZSM-5 molecular sieve catalyst is separated after the reaction is carried out until the ethylene oxide is completely converted, and the catalyst containing the following components in weight ratio of 50-75: 5-15 of polymethylphenyl ethanol, polymethylphenyl ethyl ether and the reaction product liquid of the residual polymethylbenzene or the residual aromatic oil; the dosage of the Pt/HZSM-5 molecular sieve catalyst in the reaction is 3-10wt% of the dosage of the liquid of the polymethylbenzene and the ethylene oxide. The Pt/HZSM-5 molecular sieve catalyst is provided by Shandong Xing New Material science and technology Limited, a related company of the applicant of the invention, the Pt content of the Pt is 0.05-0.1wt%, the Pt is basically loaded into the pore channels in the crystal grains of the HZSM-5 molecular sieve by a cation exchange method, and the Pt/HZSM-5 molecular sieve catalyst is obtained by reducing and drying hydrazine hydrate; the HZSM-5 molecular sieve has a silicon-aluminum ratio of 60-120, is a crystal rather than a microcrystal aggregate, has a relative crystallinity higher than 95%, has crystal grains with the external dimension of 0.8-5 mu m accounting for more than 95% of the total number of the crystal grains, has the crystal grains with the external dimension of less than 1% below 0.5 mu m, and has two main pore canal sizes of 0.53 to 0.56 and 0.51 to 0.55nm respectively. The preparation method of the catalyst is shown in CN 201910196183.1. The reaction feed of the polymethylbenzene, the ethylene oxide and the aromatic oil containing more than 80w percent of the polymethylbenzene should not contain components which can poison the catalyst, particularly the highly dispersed metal Pt, for example, the sulfur content should be less than or equal to 1 ppm.

The feeding ratio of the amount of the polymethyl benzene contained in the polymethyl benzene or the aromatic oil to the amount of the ethylene oxide is 100: the reaction effect is better when the reaction temperature is 50-75 ℃, wherein the reaction temperature is 100: 60-70 hours is economical, and the selectivity of corresponding polymethylphenyl ethanol and polymethylphenyl ether in the reaction product is more than or equal to 99 percent and the selectivity of the polymerization product of ethylene oxide in the byproduct is less than or equal to 0.1 percent (ring-opening polymerization, the products are dimeric ether alcohol and trimeric ether alcohol, and no ether alcohol product with more than tetramer is detected) calculated by the feeding of ethylene oxide. The aromatic hydrocarbon oil can contain a small amount of toluene, ethylbenzene, propylbenzene, p-xylene, mesitylene and diethylbenzene, and the aromatic hydrocarbon is less reacted with ethylene oxide under the Pt/HZSM-5 molecular sieve catalyst and reaction conditions due to the limitation of reaction activity, steric hindrance or the pore size of molecular sieve particles. The 4-position hydrogen and 5-position hydrogen of phenyl in the polymethylbenzene have higher reaction activity in the inner pore channel of the Pt/HZSM-5 molecular sieve catalyst, and react with ethylene oxide to generate the polymethylphenyl ethanol and the polymethylphenyl ethyl ether in the proportion.

The reaction product liquid can be directly used for preparing the atomized combustion control agent; or distilling under normal pressure or reduced pressure to remove more than 80% of residual polymethylbenzene or the residual material of the aromatic oil, collecting the polymethylphenylethanol and the polymethylphenetole from the bottom of the distillation tower, and using the collected materials in the preparation of the atomized combustion control agent.

The Pt/H beta molecular sieve catalyst (provided by Shandong Polyxing New Material science and technology Co., Ltd., see CN201910196183.1, the main pore size of H beta molecular sieve crystal grain is 0.56-0.75nm, and the ratio of silicon to aluminum is 40-100) has a slightly poor effect when used in the reaction, the yield of polymethyl phenyl ethyl ether is large, the by-products with larger molecular weight are increased remarkably, the ratio of polymethyl phenyl ethanol to polymethyl phenyl ethyl ether is not easy to obtain, mainly because the acid strength and the acid center number of the H beta molecular sieve are usually obviously higher than those of HZSM-5 molecular sieve, the size of pore in the crystal grain is larger, and ethylene oxide is easier to react.

In the modified alcohol-based composite environment-friendly fuel, the content ratio of methanol to the atomizing combustion control agent is preferably 100: 1.0-2.0.

The selection and specific blending proportion of the solvent oil No. 1-4 are determined according to the methanol blending amount and the octane number requirement of the prepared alcohol-based fuel; specifically, the solvent oil can be one or two of No. 1 and No. 2, and can be a mixture of one or two of No. 3 and No. 4.

The components of the metal corrosion inhibitor and the rubber swelling inhibitor meet the relevant technical requirements of the GB/T34548-2017 methanol gasoline additive for vehicles, and the addition amount of the metal corrosion inhibitor and the rubber swelling inhibitor can enable the prepared alcohol-based fuel to meet the relevant local standard requirements of the campsite. One of the metal corrosion inhibitors is a mixture of benzotriazole and pyridone in a weight ratio of 3-6: 1. The rubber swelling inhibitor can be JH4012 of SiAnjia Macro technologies, Inc.

The methanol comprises vehicle fuel methanol conforming to GB/T23510 + 2009, or qualified products, first-class products or superior products of GB/T338 + 2011 industrial methanol.

In the modified alcohol-based composite environment-friendly fuel, the polymethylphenyl ethanol polymethylphenyl ethyl ether and the diethyl malonate of the atomized combustion control agent are not methylal, anilines, halogens, harmful and forbidden compounds containing phosphorus, iron, silicon and the like specified in the current standards of motor gasoline, methanol gasoline and ethanol gasoline; the specific addition amount is determined according to the composition and performance condition of the solvent oil and the requirements on the anti-carbon deposition, particulate matter inhibition, grade, stability and the like of the prepared alcohol-based fuel, and the stability comprises the layering temperature/cloud point of the alcohol-based fuel, the storage time under different temperature conditions, and the tolerance on the water content of methanol or the water absorption capacity of the alcohol-based fuel.

From the test results and specific application effect conditions of the alcohol-based fuel prepared by the following examples and comparative examples, the technical experience of the inventor is combined, and the ingredient principle of the modified alcohol-based composite environment-friendly fuel is inferred to be as follows.

1. The polarity and surface tension of the polymethylphenyl ethanol and the polymethylphenyl ethyl ether contained in the atomized combustion control agent are between those of stronger methanol and weaker solvent oil components, so that the stability of the alcohol-based fuel is improved, the layering degree/cloud point of the alcohol-based fuel is lower, the storage and use time is longer, the water content of the methanol is allowed to be not more than 0.5wt%, and the water content of the alcohol-based fuel is not more than 0.3 wt%.

2. The atomized combustion control agent contains polymethyl phenyl ethanol and polymethyl phenyl ether, the atomization capacity of the alcohol-based fuel is improved, the fineness of oil mist droplets obtained by direct injection in a cylinder is remarkably increased, and the average outer diameter is remarkably reduced, so that the oil mist droplets can be volatilized more quickly, the surfaces of a spark plug and an oil nozzle and the inner wall of the upper part of the cylinder and the surface of a piston are not easy to wet, the combustion performance is remarkably improved, and the generated carbon particles can be remarkably refined. In the examples and application examples, no adverse effect was found between the atomized combustion controlling agent and the metal corrosion inhibitor and the rubber swell inhibitor used.

3. The polymethylphenyl ethanol contained in the atomized combustion control agent has a certain antiknock effect, namely octane value improving effect, on the premise of basically not changing the composition of the solvent oil and other technical indexes, the octane number of the alcohol-based fuel can be improved, the concentration of peroxide formed in the combustion process of the solvent oil can be reduced, the combustion speed of oil mist droplets can be reduced, and promote the sufficient combustion of the solvent oil and the palm oil, especially the aromatic hydrocarbon components, and the antiknock action or octane number promotion action of the alcohol-based fuel has certain synergy with the methanol antiknock action or octane number promotion action, so that the alcohol-based fuel is more stably and fully combusted in the running process of the direct injection engine, the generation amount of carbon particles is obviously reduced, combustion carbon deposition in the cylinder can be removed, the maintenance period and the service life of the engine can be prolonged, and the emission of pollutants in tail gas is lower; therefore, the material selection range of the solvent oil can be widened to a certain extent.

4. The concentration of peroxide formed in the solvent oil in the combustion process can be improved to a certain extent by the aid of the polymethyl phenyl ether and the palm oil contained in the atomized combustion control agent, so that the combustion speed of oil mist droplets is moderate, the effect of reducing the combustion speed of the oil mist droplets when the dosage of polymethyl phenyl ethanol is properly controlled, and the atomized combustion control agent has a certain positive effect on ensuring stable and sufficient combustion of the solvent oil and the palm oil in layered combustion and lean combustion processes, particularly stable and sufficient combustion of contained aromatic hydrocarbon.

5. Under the combined action of the principles 2-4, the speed of generating carbon deposition on the surfaces of the spark plug and the oil nozzle and the inner wall of the upper part of the cylinder and the top surface of the piston is obviously reduced, the number of generated particles is obviously reduced, and the size of the particles is reduced, namely the particles are refined, so that the generated weight of the particles is greatly reduced, and the particles are easily burnt when the particle catcher is arranged in an exhaust system, and the particle catcher needing special carbon burning regeneration is basically not blocked due to the fact that the alcohol-based fuel is arranged; the carbon cleaning agent also has certain cleaning and removing effects on the surfaces of the spark plug and the oil nozzle, the inner wall of the upper part of the cylinder and the top surface of the piston.

6. The combined action of the principles 2-4 ensures that the combustion process of the alcohol-based fuel in the engine is stable and sufficient, the applicability of the alcohol-based fuel in turbocharging + in-cylinder direct injection, natural air suction + in-cylinder direct injection, turbocharging + intake manifold multipoint electric injection, natural air suction + intake manifold multipoint electric injection and new and old gasoline engines with different discharge capacities is good, the noise and the oil consumption of the engine are low, and the fuel economy is high; the sulfur content of the methanol and the palm oil is extremely low, and the solvent oil with the sulfur content less than or equal to 10mg/kg is adopted, SO the exhaust emission of the engine is very environment-friendly, HC, CO and SO ₂ NOx and particulate matter are low in concentration, the requirement on the treatment effect of the three-way catalytic tail gas is lowered, and the particle trap is not easy to block when being matched.

Detailed Description

The present invention is specifically illustrated below by way of examples, but is not limited thereto.

Examples 1 to 7 and comparative examples 1 to 2

Aromatic hydrocarbon solutions containing polymethylphenylethanol + polymethylphenetole of examples 1-7 and comparative examples 1-2 were prepared according to the raw material ratios in Table 1.

Examples 1-7 were carried out as follows: in a fume hood, a 1000mL stainless steel small-sized reaction kettle with a jacket is filled with circulating ice water after nitrogen densification and replacement, the temperature in the kettle is reduced to below 5 ℃, aromatic hydrocarbon or aromatic oil and ethylene oxide with the amount of 0-5 ℃ are added, stirring is started, 22g of Pt/HZSM-5 molecular sieve catalyst (accounting for about 5wt% of the feeding amount of the aromatic hydrocarbon or the aromatic oil and the ethylene oxide) is added after 5min, the reaction kettle is closed, circulating water with the temperature of 32 ℃ is filled in the jacket, and the temperature in the kettle is controlled to be 30-32 ℃ for reaction; sampling 0.5mL every 1h in the reaction process, detecting by using a gas chromatography, stopping stirring for 5min before sampling to settle the catalyst, stopping stirring after no ethylene oxide is remained, pumping out all feed liquid, separating liquid and the catalyst by using a sand core funnel, filling the obtained liquid product into a small-opening reagent bottle, capping, numbering and storing, washing the catalyst by using 200 plus 220mL o-xylene for three times, then carrying out suction filtration, bagging, sealing and storing or directly using the catalyst in the reaction of the next kettle.

In comparative example 1-1, the same raw material ratio, Pt/HZSM-5 molecular sieve catalyst and operation process as those in example 1 were used, except that circulating water at 52 ℃ was introduced into the jacket after the reaction vessel was closed, and the temperature in the vessel was controlled to 50 to 52 ℃ for reaction.

Comparative examples 1-2 used the same raw material ratios and procedures as in example 1, except that 22g of Pt/H beta molecular sieve catalyst was used instead for the reaction, the temperature of circulating water in the jacket after the reactor was closed was 32 ℃, and the reaction temperature in the reactor was controlled to be 30-32 ℃.

The powdery Pt/HZSM-5 molecular sieve catalyst is prepared by CN201910196183.1 example 1, provided by Shandong Xing New Material science and technology Limited, wherein the Pt content is 0.062wt%, the powdery Pt/HZSM-5 molecular sieve catalyst is basically loaded into the intra-grain pore channels of the HZSM-5 molecular sieve by a cation exchange method, and is obtained by reducing and drying hydrazine hydrate; the HZSM-5 molecular sieve used has a silica-alumina ratio of 60, is a crystal rather than a microcrystal aggregate, has a relative crystallinity of 96 percent, has the number of crystal grains with the external dimension of 0.8-5 mu m accounting for 98.4 percent of the total number of the crystal grains and less than 0.6 percent below 0.5 mu m, has two main pore canal sizes of 0.53X 0.56 and 0.51X 0.55nm respectively, and has a specific surface area of 380m ² G, external surface area of crystal grain 0.85m ² /g。

The powdery Pt/H beta molecular sieve catalyst is provided by Shandong Polyxing New Material science and technology Limited and prepared by a method of CN201910196183.1 example 5, the Pt content of the powdery Pt/H beta molecular sieve catalyst is 0.063wt%, the powdery Pt/H beta molecular sieve catalyst is basically loaded into intra-grain pore channels of the H beta molecular sieve by a cation exchange method, and the powdery Pt/H beta molecular sieve catalyst is obtained by reducing and drying hydrazine hydrate; the used H beta molecular sieve has Si/Al ratio of 40, relative crystallinity of 95%, crystal grains with external size of 0.8-5 μm accounting for 97.4% of total crystal grains, smaller than 0.6% below 0.5 μm, and specific surface area of 563m ² G, external surface area of crystal grain 0.95m ² /g。

The used o-xylene, m-xylene, hemimellitene, pseudomellitene and ethylene oxide are all analytically pure (the sulfur content is less than or equal to 1 ppm); the used aromatic oil A, B, C is prepared from two additional analytically pure methylbenzene and ethylbenzene (sulfur content is less than or equal to 1 ppm) in analytically pure o-xylene, m-xylene, hemimellitene and hemimellitene respectively according to the mass ratio of 45:45:5:5, wherein the aromatic oil A is prepared from o-xylene, m-xylene, methylbenzene and ethylbenzene, the aromatic oil B is prepared from m-xylene, hemimellitene, methylbenzene and ethylbenzene, and the aromatic oil C is prepared from o-xylene, hemimellitene, methylbenzene and ethylbenzene.

TABLE 1 reaction charge ratio in mol units

。

In the above production processes of examples 1 to 7, the reaction time was 10 to 13 hours when no ethylene oxide remained in each reaction solution.

By comparing the peak time with that of the analytically pure substance, the judgment is that: the reaction products of examples 1 to 7 fully illustrate the reaction and effect of the polymethylbenzene with ethylene oxide described in the summary of the invention. Example 1-CH in the target reaction product of o-xylene and ethylene oxide ₂ -CH ₂ -OH or-O-CH ₂ -CH ₃ The connecting position of the compound and the 1, 2-dimethylphenyl is 4-position of a benzene ring, and the chemical names of the compound and the 1, 2-dimethylphenyl are 4- (1, 2-dimethylphenyl) -2-ethanol and 4- (1, 2-dimethylphenyl) -ether respectively; EXAMPLE 3-CH in the target reaction product of hemimellitene and ethylene oxide ₂ -CH ₂ -OH or-O-CH ₂ -CH ₃ The connecting position of the compound and the 1,2, 3-trimethylphenyl is 5-position of a benzene ring, and the chemical names are 5- (1,2, 3-triphenyl) -2-ethanol and 5- (1,2, 3-trimethylphenyl) -ethyl ether respectively; each of the liquid products obtained in examples 5 to 7 contained 4 kinds of polymethylphenylethanol and polymethylphenetole, which were identical with the target reaction products obtained in examples 1 to 4, respectively, except for the difference in aromatic hydrocarbon composition.

The liquid products obtained in examples 1 to 7 are clear and transparent, and the weight ratio of the target products, namely the polymethylphenyl ethanol and the polymethylphenyl ethyl ether, is detected to be 58.5-61.3: 8, based on the feeding amount of the ethylene oxide, the selectivity of corresponding polymethylphenyl ethanol and polymethylphenyl ethyl ether is more than or equal to 99.2 percent, and the selectivity of the polymerization product of the ethylene oxide is less than or equal to 0.1 percent (the polymerization product is dimeric ether alcohol, trimeric ether alcohol, and no ether alcohol product with more than tetramer is detected); based on the charging amount of the epoxy ethane, the selectivity of the methyl phenyl ethanol, the methyl phenyl ethyl ether, the ethyl phenyl ethanol and the ethyl phenyl ethyl ether in the liquid products obtained in the examples 5 to 7 is less than or equal to 0.2 percent.

In each of the liquid products prepared in examples 1 to 4, the content of the polymethylphenylethanol and the polymethylphenetole is 72.6 to 73.5wt%, the rest components are mainly unreacted dimethylbenzene and trimethylbenzene, and no generation of new aromatic hydrocarbons outside the feed is detected; in each of the liquid products prepared in examples 5 to 7, the content of said polymethylphenylethanol + polymethylphenetole was 66.1 to 66.9 wt%; the rest components are mainly xylene, trimethylbenzene, toluene and ethylbenzene which are not reacted, and no new aromatic hydrocarbon is generated outside the fed materials.

In the preparation process of the comparative example 1, the reaction time is 5 hours when no ethylene oxide is left in the reaction solution; the weight ratio of o-dimethylphenylethanol, i.e. 4- (1, 2-dimethylphenyl) -2-ethanol, and o-dimethylphenylether, i.e. 4- (1, 2-dimethylphenyl) -ether contained in the obtained liquid product was 60: 22, based on the ethylene oxide charge, the selectivity of o-dimethylphenylethanol + o-dimethylphenylether is 90.5%, and the selectivity of the polymerization product of ethylene oxide is 8.9% (the polymerization product is dimeric ether alcohol, trimeric ether alcohol, tetrameric ether alcohol, penta-polyether alcohol, hexa-polyether alcohol, wherein the selectivity of tetrameric ether alcohol, penta-polyether alcohol, hexa-polyether alcohol is 4.6%).

In the preparation process of comparative example 2, the reaction time is 6 hours when no ethylene oxide is left in the reaction solution; the weight ratio of o-dimethylphenylethanol, i.e. 4- (1, 2-dimethylphenyl) -2-ethanol, and o-dimethylphenylether, i.e. 4- (1, 2-dimethylphenyl) -ether contained in the obtained liquid product was 60: 30, based on the ethylene oxide feed, the selectivity of o-dimethylphenylethanol + o-dimethylphenylether is 96.1%, and the selectivity of the polymerization product of ethylene oxide is 3.7% (the polymerization product is dimeric ether alcohol, trimeric ether alcohol, tetrameric ether alcohol, penta-polyether alcohol, wherein the selectivity of tetrameric ether alcohol, penta-polyether alcohol is 1.4%).

Examples 8 to 22, comparative examples 3 to 12

The compositions of the solvent oils used for preparing the alcohol-based fuels of examples 8 to 22 and comparative examples 3 to 12 were, as shown in Table 2, prepared by mixing the solvent oils in the weight parts shown. The octane number (RON) of the solvent oil M-Q is 88.5-90; the sulfur content of each solvent oil is less than or equal to 5mg/kg, and other indexes meet the regulations of GB1922-2006, wherein the solvent oil 1 is of a common type, the solvent oils 2 and 4 are of medium aromatic type, and the solvent oil 3 is of a low aromatic type.

TABLE 2 composition of mineral spirit M, N, O, P, Q, parts by weight

。

40kg of each of the alcohol-based fuels of examples 8 to 22 and comparative examples 3 to 12 was prepared in the proportions shown in Table 3; wherein the used methanol is a qualified product which accords with GB/T338-2011 industrial methanol, and the water content is less than or equal to 0.20 wt%; the metal corrosion inhibitor is a mixture powder of benzotriazole and pyridone with the weight ratio of 4.5:1, and the mixture powder is uniformly mixed and ground into-600 meshes; the rubber swelling inhibitor adopts JH4012 of SiAnjia macro science and technology limited company. The preparation process comprises the following steps: and (3) after nitrogen replacement in the stirring tank, sequentially adding required amount of methanol, an atomization combustion control agent, a metal corrosion inhibitor and a rubber swelling inhibitor, stirring for 30min until powder is completely dissolved and uniformly mixed, adding palm oil and solvent oil, and stirring for 30min until the mixture is uniformly dissolved to obtain the alcohol-based fuel.

The octane numbers (RON) of the alcohol-based fuels obtained in examples 8, 9, 19, 21 and 22 and comparative example 12 were respectively 92.3, 92.2, 95.5, 92.7, 95.4 and 93.6 by sampling and testing, and according to the practical experience of the applicant, it was considered that the octane numbers (RON) of the alcohol-based fuels obtained in examples 10 to 18 and comparative examples 3 to 8 were higher than 92 and the octane numbers (RON) of the alcohol-based fuels obtained in example 20 and comparative examples 9 to 11 were higher than 95.

Example 8, comparative example 12, which produced a significant difference in octane number (RON) of the alcohol-based fuels, demonstrated that 4- (1, 2-dimethylphenyl) -2-ethanol had much lower antiknock, i.e., octane number boost, in both alcohol-based fuels than the prior art (CN 109929622B an ethanol gasoline dispersant and ethanol gasoline containing the dispersant) 2- (p-methylphenyl) -2-butanol; the following application example 1, example 8, and comparative example 12 show significant differences in engine fuel consumption, noise level, and idle speed for alcohol-based fuels, and also show that 4- (1, 2-dimethylphenyl) -2-ethanol has significantly higher atomization and combustion, i.e., power, effects in the direct cylinder injection engines used than 2- (p-methylphenyl) -2-butanol.

TABLE 3 alcohol-based Fuel blend ratio

。

The alcohol-based fuels prepared in examples 8-22 were individually tested for stability, and the test methods and results included: (1) each 500mL double-packaged glass bottle is shielded and sealed, and is placed for 30 days at the temperature of minus 20 ℃ and 30 ℃ respectively without visible change; (2) each sample was taken from a 500mL two-part glass bottle, 2mL of water was added to the bottle, the bottle was mixed, sealed in a dark place, and left at-20 ℃ and 30 ℃ for 30 days without any visible change.

Application example 1

The alcohol-based fuels of examples 8-22 and comparative examples 3-12 were subjected to application tests in a representative six-wheeled vehicle (engine four-cylinder 1.5L turbocharging + direct injection in cylinder, 7-speed wet dual clutch automatic transmission, particulate trap, tank volume 55L), 48-50L for each alcohol-based fuel, all prepared 15-17 days before use; and (3) inspecting the performances of the alcohol-based fuels in the aspects of engine power performance, oil consumption and noise. The vehicle age is 20 months, the vehicle runs 35000km after being added with national standard No. 92 national six gasoline, runs 2200km after being added with national standard No. 92 national six gasoline, and runs 8000km after being added with No. 92M 15 and No. 95M 30 methanol gasoline in each test; before testing, SP-grade low-ash fully-synthesized engine oil with proper viscosity is adopted, the oil-gas separator has normal effect, the engine state is good, engine oil is not burnt, and carbon deposition in a cylinder, carbon deposition on the back of an air inlet manifold and the back of an air inlet valve are detected to be slight. The test takes 3 months, and the running is carried out for 24000km altogether, wherein the running is carried out for 3800km by adding national standard No. 92 national six gasoline before 6000km, then for 2200km by adding national standard No. 95 national six gasoline, and then for 18000km by adding the alcohol-based fuel of the examples 8-22 and the comparative examples 2-11, wherein after the first test of the alcohol-based fuel of the examples 8 and the comparative examples 5, the higher-efficiency oil nozzles with more holes are respectively used, and the original oil nozzles are replaced after each test; the air temperature is 20-25 ℃ and the wind speed is less than or equal to 6m/s during testing; the air quality of the driving route is excellent for most of the time, good for a small part of the time, slight or more haze does not occur, and dust does not occur; the air inlet filter is replaced once every 4000km, the same engine oil is replaced once every 6000km, and the 100km test effect after the air inlet filter and the engine oil are replaced is not included in the statistical calculation. In the test process, the driving mileage of the vehicle with constant speed of 60km/h, 80km/h and 100km/h and wind speed less than or equal to 3.3m/s is ensured to be more than 15000 km. The purpose of using SP grade low ash fully synthetic engine oil is to avoid the impact of carbon dust produced by possible light engine oil burn on the particulate trap.

The test items include: (1) comparing the engine oil consumption and the noise when the speed of the newly-built asphalt pavement highway with the basic level is fixed at 60km/h, 80km/h and 100 km/h; (2) comparing engine oil consumption and noise when the speed of a newly-built asphalt pavement long-slope road with the gradient of about 3% is fixed at 60km/h, 80km/h and 100 km/h; (3) comparing the idle speed of the engine after the vehicle is started to run for 50 km; (4) comparing the carbon burning regeneration conditions of the particle trap; (5) carbon deposition conditions in the cylinder after the test.

The test results include the following.

(1) When the speed of a newly-built asphalt pavement highway with the basic level is fixed at 60km/h, 80km/h and 100km/h and the No. 92 alcohol-based fuel of the examples 8-18 and 21 is added, the average value of the oil consumption of the engine is reduced by more than 5 percent (5-10 percent) compared with that of the oil consumption of the engine added with No. 92 gasoline at the initial stage, and the noise level of the engine is equivalent to or slightly lower than that of the engine; when the No. 92 alcohol-based fuel of comparative examples 3-4, 6 and 11 is added, the average oil consumption of the engine is basically equal to that of the engine added with No. 92 gasoline at the initial stage, and the noise level of the engine is equivalent to or slightly higher than that of the engine; when the No. 92 alcohol-based fuels of comparative examples 4 and 7-8 are added, the average fuel consumption of the engine is improved by 2-3% compared with that of the engine added with No. 92 gasoline at the initial stage, and the noise level of the engine is obviously higher. When the 95 # alcohol-based fuel of the embodiment 19-20 and 22 is added, the average oil consumption of the engine is improved by less than 4 percent compared with the initial 95 # gasoline, and the noise level of the engine is equivalent to or slightly lower than that of the engine; when the 95 # alcohol-based fuel of the comparative examples 9-10 is added, the average fuel consumption of the engine is improved by 8-10% compared with the initial 95 # gasoline, and the noise level of the engine is equivalent to or slightly higher. The oil consumption of the alcohol-based fuel in the embodiment 8 when the high-efficiency fuel spray nozzles are respectively replaced after the first test is less than 1% than that of the original fuel spray nozzles, and the oil consumption of the alcohol-based fuel in the comparative example 5 when the high-efficiency fuel spray nozzles are respectively replaced after the first test is about 2% than that of the original fuel spray nozzles.

(2) When the speed of a newly-built asphalt pavement long-slope highway with the gradient of about 3 percent is fixed at 60km/h, 80km/h and 100km/h and the No. 92 alcohol-based fuel of the examples 8-18 and 21 is added, the average oil consumption of the engine is reduced by more than 6 percent compared with that of the engine added with No. 92 gasoline at the initial stage, and the noise level of the engine is equivalent to or slightly lower than that of the engine; when the No. 92 alcohol-based fuel of comparative examples 3-4, 6 and 11 is added, the average oil consumption of the engine is basically equal to that of the engine added with No. 92 gasoline at the initial stage, and the noise level of the engine is equivalent to or slightly higher than that of the engine; when the No. 92 alcohol-based fuels of comparative examples 4 and 7-8 are added, the average fuel consumption of the engine is improved by 1-3% compared with that of the engine added with No. 92 gasoline at the initial stage, and the noise level of the engine is obviously higher. When the 95 # alcohol-based fuel of the examples 19-20 and 22 is added, the average fuel consumption of the engine is improved by less than 5 percent compared with the initial 95 # gasoline, and the noise level of the engine is equivalent; when the 95 th alcohol-based fuel of the comparative examples 9-10 is added, the oil consumption of the engine is improved by 10-12% compared with the initial oil consumption of the 95 th gasoline, and the noise level of the engine is slightly higher. In the embodiment 8, the oil consumption when the high-efficiency oil spray nozzles are respectively replaced after the first test of the alcohol-based fuel is only reduced by less than 1% compared with the oil spray nozzles adopted, and in the comparative example 4, the oil consumption when the high-efficiency oil spray nozzles are respectively replaced after the first test of the alcohol-based fuel is reduced by about 3% compared with the oil spray nozzles adopted.

(3) The idling speed of the engine after the vehicle is started for 50km is reduced by 30-50rpm when the No. 92 alcohol-based fuel of examples 8-18 and 21 is added compared with that when No. 92 gasoline is added in the initial stage of the test; 10-25rpm reduction when adding alcohol-based fuel No. 92 of comparative examples 3-4, 6, 11; when the No. 92 alcohol-based fuel of comparative examples 4, 7-8 is added, the rpm is increased by 20-40 rpm. Compared with the initial stage of the test when 95 # gasoline is added, the speed is increased by 20-35rpm when 95 # alcohol-based fuels of examples 19-20 and 22 are added; the addition of the 95 th alcohol-based fuel of comparative examples 9-10 increased 40-60 rpm.

(4) During the test period of adding the alcohol-based fuel, no carbon burning regeneration prompt of the particle trap is found; during the period of adding No. 92 and No. 95 gasoline in the initial period, the carbon burning regeneration of the particle catcher is suggested for 4 times, and the engine runs to the end of the carbon burning regeneration every time, wherein 1 time seriously influences the power output of the engine.

(5) After the test of adding alcohol-based fuel is finished, the carbon deposition condition in each cylinder is checked through the spark plug hole endoscopic probe, and the slight carbon deposition on the surfaces of the spark plug and the oil nozzle, the inner wall of the upper part of the cylinder and the top surface of the piston is basically removed.

Application example 2

200kg of the alcohol-based fuels of examples 8 and 22 are prepared for each time, and the continuous addition effect of the alcohol-based fuels under normal use conditions is examined in 6 representative vehicles; the engines of the 6 vehicles do not burn engine oil, wherein the 1 st vehicle is a vehicle which is provided with four cylinders and 1.5L of turbocharging + in-cylinder direct injection + particle trap in application example 1 and is continuously used for the test, the 2 nd vehicle is a vehicle which is provided with four cylinders and 2.0L of turbocharging + in-cylinder direct injection + particle trap configuration, the 3 rd vehicle is a vehicle which is provided with four cylinders and 1.5L of turbocharging + in-cylinder direct injection + cylinder direct injection configuration, the 4 th vehicle is a vehicle which is provided with four cylinders and 1.5L of turbocharging + multi-point electric injection of an intake manifold, the 5 th vehicle is a vehicle which is provided with 2.0L of natural air suction + multi-point electric injection of the intake manifold, the 6 th vehicle is a vehicle which is provided with 1.6L of natural air suction + multi-point electric injection of the intake manifold and has a constant-speed cruise function, and the 1,2 and 5 th vehicles have an accurate valve control technology.

The vehicle ages of 2 nd to 6 th vehicles before the test are respectively 17 months, 18 months, 51 months, 22 months and 58 months, the traveled mileage is 42000, 46000, 98000, 50000 and 144000km respectively, the engine state is good, the carbon deposition in the cylinder, the carbon deposition on the back of an intake manifold and an intake valve are checked to be light, the effect of an oil-gas separator is normal, and the vehicle ages are 10000km after the test is performed by adding methanol gasoline No. 92M 15 and methanol gasoline No. 95M 30 respectively before the test.

In this test, each vehicle continued to use an SP grade low ash fully synthetic engine oil of suitable viscosity. The 6 vehicles finish the test when running for 26000km within 3-5 months; wherein, the first 6000km is firstly added with national standard No. 92 national hexa gasoline for running 3000km, then is added with national standard No. 95 national hexa gasoline for running 3000km, and then is added with No. 92 alcohol-based fuel for running 10000km, and then is added with No. 95 alcohol-based fuel for running 10000 km; the air temperature is 20-35 ℃ during driving, the wind speed is less than or equal to 10m/s, and only the test effect condition when the wind speed is less than or equal to 3.3m/s is recorded; the air quality of the driving route is excellent in most of the time, good in a small part of the time, severe or more haze occurs at the end, and dust and sand are encountered at the end; the air inlet filter is replaced once every 5000km, the low-ash fully-synthesized engine oil with the proper viscosity SP level required by each vehicle is replaced once every 6000km, and the 100km test effect after the air inlet filter and the engine oil are replaced is not included in statistical calculation. And the openings of the exhaust pipes behind the three-way catalysts of the vehicles are respectively connected with gas analysis equipment, and the tail gas components in a stable running state after the vehicles start to run for 50km are sampled and detected at regular time.

The test items include: (1) comparing the engine oil consumption and the noise when the speed of the newly-built asphalt pavement highway with the basic level is fixed at 60km/h, 80km/h and 100 km/h; (2) comparing engine oil consumption and noise when the speed of a newly-built asphalt pavement long-slope road with the gradient of about 3% is fixed at 60km/h, 80km/h and 100 km/h; (3) comparing the idle speed of the engine after the vehicle is started to run for 50 km; (4) comparing tail gas components in a stable running state after the vehicle starts to run for 50 km; (5) comparing the special carbon burning regeneration conditions when the particle catcher is available; (6) and comparing the carbon deposition condition in the cylinder after the test with that of the previous 6000km plus domestic six gasoline at the end of running. In the test process, the driving mileage of each vehicle is ensured to be more than 15000km when the speed of each vehicle is constant at 60km/h, 80km/h and 100km/h and the wind speed is less than or equal to 3.3 m/s.

The test results include the following.

(1) When the speed of a newly-built asphalt pavement highway with the basic level is fixed at 60km/h, 80km/h and 100km/h and the No. 92 alcohol-based fuel of the embodiment 8 is added, the average oil consumption of the engine is reduced by more than 5 percent compared with that of the engine added with No. 92 gasoline at the initial stage, and the noise level of the engine is equivalent to or slightly lower than that of the engine; when the 95 th alcohol-based fuel of example 22 was added, the average fuel consumption of the engine was improved by less than 4% compared with the initial addition of the 95 th gasoline, and the engine noise level was comparable to or slightly lower than that of the engine.

(2) When the speed of a newly-built asphalt pavement long-slope highway with the gradient of about 3 percent is fixed at 60km/h, 80km/h and 100km/h and the No. 92 alcohol-based fuel of the embodiment 8 is added, the average oil consumption of the engine is reduced by more than 5 percent compared with that of the engine added with No. 92 gasoline at the initial stage, and the noise level of the engine is equivalent to or slightly lower than that of the engine; when the 95 th alcohol-based fuel of example 22 was added, the fuel consumption of the engine was improved by 5% or less in average value as compared with the initial addition of the 95 th gasoline, and the engine noise level was comparable.

(3) The idling speed of the engine after the vehicle is started for 50km is reduced by 25-40rpm when the No. 92 alcohol-based fuel of the embodiment 8 is added and is increased by 20-45rpm when the No. 95 alcohol-based fuel of the embodiment 22 is added compared with the idling speed of the engine when No. 92 and No. 95 gasoline are added in the initial period of the test.

(4) The exhaust gas composition in the steady running state after each vehicle started running for 50km was reduced by 70% or more in both the NOx and CO contents when the alcohol-based fuel No. 92 of example 8 and the alcohol-based fuel No. 95 of example 22 were added, and the CH and CH contents were reduced as compared with the case when the gasoline Nos. 92 and 95 were added in the initial period of the test ₄ The content is reduced by more than 20 percent.

(5) During the test period of the 1 st and 2 nd vehicles adding the alcohol-based fuel, no carbon burning regeneration prompt of the particle catcher is found; during the period of adding No. 92 and No. 95 gasoline in the initial period, 5 times of carbon burning regeneration of the particle trap are discovered together, and the vehicle runs to the end of the carbon burning regeneration every time, wherein 2 times seriously affect the power output of the engine.

(6) After the test is finished, carbon deposits on the surfaces of a spark plug and an oil nozzle in each cylinder of each vehicle, the inner wall of the upper part of the cylinder and the top surface of the piston are detected through a spark plug hole endoscopic probe, and the fact that the 1 st vehicle is completely removed, the 2 nd to 6 th vehicles are obviously reduced compared with the vehicles before the alcohol-based fuel is used, and the carbon deposits in individual cylinders are basically removed is found.

The national standard No. 92 or No. 95 national six gasoline is filled in a normal filling station with good credit in a test place, and the measurement is known to be accurate and the quality is best.

Claims

1. A low-proportion methanol gasoline for vehicles comprises, by weight, 10-40% of methanol, 5-10% of palm oil, 0.1-0.5% of an atomization combustion control agent, 0.02-0.1% of a metal corrosion inhibitor, 0.02-0.2% of a rubber swelling inhibitor and the balance solvent oil; the sulfur content of the solvent oil is less than or equal to 10mg/kg, and the solvent oil is No. 1-4 solvent oil; the atomized combustion control agent contains polymethylphenylethanol ((CH) ₃ ) _X -C ₆ H _6-X-1 )-CH ₂ -CH ₂ -OH, polymethylphenyl ethyl ether ((CH) ₃ ) _X -C ₆ H _6-X-1 )-O-CH ₂ -CH ₃ The weight ratio of (A) to (B) is 50-75: 5-15, polymethylphenylethanol + polymethylphenetole ≥ 60wt%, wherein X =2 or 3; when X =2, the polymethylphenyl group is o-dimethylphenyl, i.e., 1, 2-dimethylphenyl, or m-dimethylphenyl, i.e., 1, 3-dimethylphenyl, and when the polymethylphenyl group is o-dimethylphenyl, the-CH group ₂ -CH ₂ -OH or-O-CH ₂ -CH ₃ The bonding position to the benzene ring is 4-position, and when the polymethylphenyl group is m-dimethylphenyl, the-CH ₂ -CH ₂ -OH or-O-CH ₂ -CH ₃ The linking position with the benzene ring is 5-position; when X =3 the polymethylphenyl group is a vicinal trimethylphenyl group, i.e. a 1,2, 3-trimethylphenyl group, or a partial trimethylphenyl group, i.e. a 1,2, 4-trimethylphenyl group, when the-CH group is present ₂ -CH ₂ -OH or-O-CH ₂ -CH ₃ The connecting positions with benzene rings are all 5 positions.

2. The modified alcohol-based composite environment-friendly fuel as claimed in claim 1, wherein the atomized combustion control agent comprises the following components in a weight ratio of the polymethylphenyl ethanol to the polymethylphenyl ethyl ether of 58-63: 8.

3. the low-proportion methanol gasoline for vehicles according to claim 1, wherein the polymethylphenylethanol and the polymethylphenetole in the atomized combustion control agent are synthesized by reacting, as a raw material for the polymethylbenzene, polymethylbenzene selected from one or more of o-xylene, m-xylene, hemimellitene and mesitylene, or an aromatic oil containing 80wt% or more of the polymethylbenzene with ethylene oxide.

4. The modified alcohol-based composite environment-friendly fuel as claimed in claim 3, wherein the preparation method of the polymethylphenyl ethanol and the polymethylphenyl ethyl ether in the atomized combustion control agent is as follows: one or more than one of o-xylene, m-xylene, hemimellitene and unsym-trimethylbenzene or aromatic oil containing more than 80wt% of the polymethylbenzene is mixed with ethylene oxide uniformly according to the required proportion, a powdery Pt/HZSM-5 molecular sieve catalyst is added, the reaction temperature is 30-40 ℃, the mixture is stirred and reacted for 8-20 hours under the condition of liquid phase, the Pt/HZSM-5 molecular sieve catalyst is separated after the reaction is carried out until the ethylene oxide is completely converted, and the catalyst containing the following components in weight ratio of 50-75: 5-15 of polymethylphenyl ethanol, polymethylphenyl ethyl ether and the reaction product liquid of the residual polymethylbenzene or the residual aromatic oil; the dosage of the Pt/HZSM-5 molecular sieve catalyst in the reaction is 3-10wt% of the dosage of the polymethylbenzene and the ethylene oxide liquid; the Pt content of the Pt/HZSM-5 molecular sieve catalyst is 0.05-0.1wt%, and the Pt/HZSM-5 molecular sieve catalyst is loaded into an intra-grain pore channel of the HZSM-5 molecular sieve by a cation exchange method, reduced by hydrazine hydrate and dried to obtain the catalyst; the HZSM-5 molecular sieve has a silicon-aluminum ratio of 60-120, is a crystal rather than a microcrystal aggregate, has a relative crystallinity higher than 95%, has crystal grains with the external dimension of 0.8-5 mu m accounting for more than 95% of the total number of the crystal grains, has the crystal grains with the external dimension of less than 1% below 0.5 mu m, and has two main pore canal sizes of 0.53 to 0.56 and 0.51 to 0.55nm respectively.

5. The modified alcohol-based composite environment-friendly fuel as claimed in claim 4, wherein in the preparation process of the polymethylphenylethanol and the polymethylphenetole, the dosage ratio of the amount of the materials of the polymethylbenzene and the ethylene oxide contained in the polymethylbenzene or the aromatic oil is 100: 50-75.

6. The modified alcohol-based composite environment-friendly fuel as claimed in claim 1, wherein the weight content ratio of the methanol to the atomized combustion control agent is 100: 1.0-2.0.

7. The modified alcohol-based composite environment-friendly fuel as claimed in claim 1, wherein the solvent oil is one or two of solvent oil No. 1 and No. 2, and a mixture of one or two of solvent oil No. 3 and No. 4.

8. The modified alcohol-based composite environment-friendly fuel as claimed in claim 1, wherein the metal corrosion inhibitor is a mixture of benzotriazole and pyridone in a weight ratio of 3-6: 1; the rubber swelling inhibitor is JH4012 of SiAnjia macro science and technology limited.

9. The modified alcohol-based composite environment-friendly fuel as claimed in claim 1, wherein the methanol comprises vehicle fuel methanol conforming to GB/T23510-2009, or qualified products, first-class products or superior products of GB/T338-2011 industrial methanol.