GB2509288A - Alternative fuel for internal combustion engine, containing biobutanol - Google Patents

Abstract

The present invention relates to an alternative fuel composition for an internal combustion engine, the alternative fuel for an internal combustion engine comprising: 1-88 wt% of biobutanol or a mixture of biobutanol and butanol; 3-75 wt% of a paraffin-based hydrocarbon solvent; 3-35 wt% of toluene; and 6-30 wt% of xylene, based on the total weight of the composition.

Description

ALTERNATIVE FUEL FOR INTERNAL COMBUSTION ENGINE CONTAINING

BIOBUTANOL

[Cross-Reference To Related ?pplications]

This application is a Nationai phase of PCT patent Application No. PCT/KR2012/007385 having International filing date of September 14, 2012 which claims the benefit of priority of Korean Patent Application No. 10-2011-0092854 filed on September 14, 2011. The contents of the above applications are all incorporated by reference as if fully set forth herein in their entirety.

[Technical Field]

The present invention relates to a fuel composition for internal combustion engines. The present invention provides a fuel composition for internal combustion engines as an IS alternative fuel which is applicable not only to an engine using gasoline as a fuel but also to a diesel engine.

[Background Art]

As problems of an exhaustion of fossil fuel and an environmental pollution are getting serious, it is not too much to say that the world is now in a war with energy and the environment. Particularly, in order to conform with an international environmental regulation (Kyoto Protocol) which is strengthened daily due to a higher oil price, it is inevitable now to hurry up the development of an alternative fuel.

In order to overcome the above problems, approaches to develop alternative fuels with a high fuel efficiency using bioethanol and the like have been continually made, but there was still a need to resolve the problems such as an excessive guantity of fuel consumption. Also, there was a need to develop a high performance alternative fuel which can prevent a phase separation phenomenon of water present in a small amount in the fuel.

[Detailed Description]

[Technical Problem] The present invention has been made to resolve the above mentioned problems occurring in the prior art, and it Is an object of the present invention to provide a fuel composition in which a fuel oil for internal combustion engines does not exhibit a phase separation phenomenon of water present in a small amount in the fuel during long-term storage and each components are fully mixed, thereby having less knock occurrence and greater combustion efficiency. Also, it is another object of the present invention to provide a novel fuel composition containing biobutanol, having enhanced octane nuxfrber, lowered harmful exhaust gas and thereby reduced environmental pollutants.

[Technical Solution] In order to achieve the above objects, the fuel composition for internal combustion engines containing biobutanol according to the present invention comprises a) l'88% by weight of biobutanol or a mixture of biobutanol and butanol, b) 375% by weight of paraffinic hydrocarbon solvents, c) 335% by weight of toluene and d) 63O% by weight of xylene, based on the total weight of the composition.

In the present invention, the above fuel composition further comprises one or more additives selected from the group consisting of e) l2O I by weight of butane derivatives, f) li30% by weight of pentane derivatives, g) l4O% by weight of hexane derivatives, h) li45% by weight of benzene derivatives and i) P2O% by weight of heptane derivatives.

The above component b) used herein comprises paraffinic hydrocarbon or paraffinic hydrocarbon solvents having 4 to 28 carbon atoms or a mixture thereof.

Further, the fuel composition of the present invention may further comprise one or more additives selected from the group consisting of l-85% by weight of aliphatic alkane and alicyclic alkane having 5 to 40 carbon atoms, 0.0li85% by weight of biodiesel, l43% by weight of kerosene, l32% by weight of Hi-sene, l36% by weight of Hi-nine, 0.l---5% by weight of lubricant base oil, l9% by weight of butyl cellosolve, l-ll% by weight of ethyl cellcsolve, 1-43% by weight of isoprcpanol, ll2% by weight of isobutanol and l49% by weight of aromatic hydrocarbon mixture.

Further, methyl tertiary butyl ether (MTBE), ethyl tertiary butyl ether (ETBE) and the like are conventionally used as an octane number enhancer. However, according to the present invention, biobutanol itself serves to increase an octane number and thus, there is no need to use a separate octane number enhancer.

When using bioethanol, there is a disadvantage that bioethanol may absorb atmospheric moisture, thereby resulting in a phase separation phenomenon and a corrosion in transportation pipe. As such, there is need to use a corrosion inhibitor. However, the present invention has an advantage that it is not necessary to use a separate corrosion inhibitor.

Additionally, the alternative fuel for internal combustion engines according to the present invention may comprise the above fuel composition alone or in a mixture with a fuel for internal combustion engines or an alcohol fuel.

[Effect of Invention] The fuel composition for internal combustion engines according to the present invention can, when used as a fuel for internal combustion engines, significantly reduce the production and discharge of air pollutants from environment aspects, as compared with a conventional gasoline fuel. Also, the fuel composition of the present invention has increased cold-start up property and power performance as well as reduced noise generation in terms of energy efficiency, as compared with a conventional fuel for internal combustion engines.

[Best Mode for Carrying Out the Invention]

The present invention relates to a fuel composition for internal combustion engines, and also relates to an alternative fuel which comprises l88% by weight of biobutanol or a mixture of biobutanol and butanol, 375% by weight of paraffinic hydrocarbon solvents having 428 carbon atoms, 335% by weight of toluene and 63O% by weight of xylene, based on the total weight of the composition.

In the present invention, a composition ratio is based on the total weight of the composition, unless described otherwise.

Also, the present invention provides a fuel composition which further comprises, as a phase separation inhibitor, one or more components selected from the group consisting of l-9% weight of butyl cellosolve, ll1% by weight of ethyl cellosolve or a mixture thereof, based on the total weight of the composition. Furthermore, the fuel composition of the present invention may further comprise 1-13% by weight of isopropanol, ll2% by weight of isobutanol, O.OOl6% by weight of rosin, rosin derivatives, rosin acid compound or a mixture thereof, based on the total weight of the composition. Optionally, the fuel composition for internal combustion engines according to the present invention may further comprise 1-49% by weight of aromatic hydrocarbon mixture.

The above fuel composition for internal combustion engines further comprises, more preferably, 15-6O% by weight of biobutanol or a mixture of biobutanol and butanol; 2O5O% by weight of a mixture of paraffinic hydrocarbons having 4-28 carbon atoms; 5-49% by weight of toluene; 6il8% by weight of xylene; one or more phase separation inhibitor selected from 2-4% weight of butyl cellosolve, 0.5-4% by weight of ethyl cellosolve or a mixture thereof; 0.5--2% by weight of rosin, rosin derivatives, and rosin acid or a mixture thereof; and 3-42% by weight of aromatic hydrocarbon mixture, based on the total weight of the composition.

If necessary, the fuel composition of the present invention may further comprise one or more components selected from 2-4% by weight of isopropanol and 2-7% by weight of isobutanol, based on the total weight of the composition, thereby maximizing the phase separation inhibition effect.

In other aspect, the present invention provides a fuel composition for internal combustion engines which further comprises one or more oomponents selected from the group consisting of O.01--85% by weighc of biodiesel or a known diesel or a mixture thereof, 1-43% by weight of kerosene, 1-42% by weight of Hi-sene, l--36% by weigh of Hi-nine, and 0.1--SI by weight of lubricant base oil.

In the individual aspects of the invention as mentioned above, the fuel composition may comprise, independently, one or more components selected from l2O% by weight of butane derivatives, i3O% by weight of pentane derivatives, i4O% by weight of hexane derivatives, l45% by weight of benzene derivatives, and 12O% by weight of heptane derivatives. It is apparent to a person skilled in the art that, in the present invention, the butane derivatives, the pentane derivatives, the hexane derivatives, the benzene derivatives and the heptane derivatives refer collectively to the derivatives and/or isomers thereof, respectively. Therefore, further detailed description is omitted, but respective components used in the present invention will be described in detail below.

For example, the benzene derivative refers to benzene and one or more benzene derivatives selected from solvents in which hydrogen radical of benzene is substituted by one through three Cl-C3 alkyl groups, and includes toluene, xylene, benzene, ethylbenzene, l-methyl-3-ethylbenzene, 1,3, 5-trimethylbenzene, 1,2, 4-trimethylbenzene, 1,2, 3-trimethylbenzene, 1-ethyl-2, 4-dimethylbenzene, indane, 1-methyl-3-proplybenzene and the like.

And the butane, pentane, hexane and heptane derivatives refer collectively to compounds belonging to isomers and derivatives thereof. Here, benzene may be used, but it is preferable to not use the same in order to prevent an environment pollution.

Furthermore, a lubricant base oil may be used iu the fuel composition of the present invention. The lubricant base oil includes a paraffinic base oil (content of the base oil: 457O%), a naphthenic base oil (content of the base oil: 6575%), an aromatic base oil (content of the base oil: 2C25%) and the like. Specifically, examples thereof include one or more selected from engine oil, general industrial oil, electric insulating oil, refrigeration oil, process oil and the like. When two objects are in contact with each other and one object relatively moves against the other object, resistance that prevents the movement is called friction. The lubricant base oil may be used to reduce the friction force or eliminate heat generated by the friction. When the lubricant base oil is used in an amount of O.l5% by weight range, it is helpful to increase the fuel efficiency and reduce the heat due to the friction.

If necessary, the rosin, rosin derivative and rosin acid compound may be used in the fuel composition of the present invention. The rosin acid used herein refers collectively to organic acids contained in the rosin which can be obtained by distilling a fine resin. Rosin acid is a natllral resin acid obtained by distilling a fine resin. The resin acid is a valuable resource which can hardly be obtained from natural substances other than trees. From old times, fine resin has been used for the purpose of painting vessels or ships to prevent corrosion and of preventing slipping on strings of a

S

stringed instrument. However, iii most cases, the fine resin is modified for various uses. The chemical structures of resin acids comprise chemicaiiy active double bonds.

Those double bonds raise reactions between the molecules of the same resin acid or between the resin acid and other compounds (for example, maleic acid) to produce so-called polymerized Rosin. Since the double bonds result in instability when the resin acid is left in air, hydrogen is added to stabilize the resin acid. This is called hydrogenated rosin, and used for preparing synthetic resin, ink or the like.

The rosin acid refers collectively to organic acids obtained from distillation of a fine resin, and includes abietic acid, neoabietic acid, levopimaric acid, hydroabietic acid, pimaric acid, dextonic acid, palustric acid, or the like.

When the rosin acid is in the amount of O.5-2% by weight, it is effective in preventing corrosion.

Biobutanol used as the component a) of the present invention is produced from biomass. When using the above alcohol component, it has excellent miscibility with water and thus phase separation does not occur. Therefore, it is very advantageous that the fuel composition of the present invention has good fuel efficiency and anti-knocking property without addition of separate phase separation inhibitor. Biobutanol serves to provide a high octane number and a high compression ratio for the fuel composition of the present invention. It also serves to prevent a phase separation and achieve a high combustion efficiency. Further, biobutanol has low vapor pressure and thus it can be used in a large quantity.

Particularly, biobutanol has high density, a cold start-up property is excellent. The content of biobutanol may range from l-88% by weight and preferably 27O% by weight based on the total weight of the composition. If the content is less than the range, it is impossible to obtain sufficient effect of increase in the octane number and sufficient compression ratio.

Meanwhile, if the oontent exoeeds the range, fuel consumption is increased.

The component b) used in the present invention may include paraffinic hydrocarbon, paraffinio hydrocarbon solvent or a mixture thereof.

More specifically, the fuel composition for internal combustion engines is characterized in that the component b) includes C4C28 paraffinic hydrocarbon, paraffinic hydrocarbon solvent or a mixture thereof mixed with small amount of cycloparaffinic hydrocarbon or the like, which are liquids at room temperature.

Examples thereof include benzine, rubber gasoline, solvent naphtha, mineral spirits, cleaning solvent, Stoddard solvent and aromatic solvent. Trivial names thereof include canadol, isoparaffin hydrocarbon, ligroin, naphtha ligroin, refined solvent naphtha, VM&P naphtha, vanish marker's naphtha, naphtha Stoddard solvent, white spirits, Stoddard solvent naphtha, Stoddard solvent organic solvent, enamel thinner, mineral thinner, rubber solvent(naphtha), Vasol, hydrotreated light straight run(petroleum), naphtha(petroleum), hydrotreated light naphtha or the like. Brand name thereof conventionally used all over the world include 1520 Naphtha and Fxxol Hexane Fluid available from FxxonMobil; Techsol-S and kixxsol available from GS-Caltex; and BPi (Special Boiling Point) , SBP4 (Special Boiling Point), Solvent-i and Solvent-5(cleaning solvent) available from 5K. When they are used in the content of 375% by weight and preferably 2050% by weight, it is possible to obtain most appropriately the desired effect, to prevent clog of a nozzle attached to the internal cor±ustion engines due to impllnties, and to improve the soot preventing effect.

In the present invention, toluene or xylene may be further added in order to more improve explosive force or fuel efficiency of an engine. When using toluene in the range of 335% by weight and preferably l0-30% by weight and xylene in the range of 630% by weight based on the total weight of the composition, it is possible to sufficiently improve the explosive force and fuel efficiency of the engine without generation of soot and smoke due to incomplete combustion. The xylene component refers generally to xylene isomer alone or a mixture thereof.

In the present invention, the phase separation inhibitor is a component which prevents generation of moisture during long-term storage of the fuel and condensation of water in the fuel vessel at the time of injecting the fuel into an automobile; or which prevents separation of some water incorporated from other components to cause knocking at the time of fuel combustion in engine, or lowering the fnel efficiency. In the present invention, one or more components selected from P9% by weight of butyl cellosolve, P41% by weight of ethyl cellosolve or the like may be used.

Additionally, one or more components selected from P43% by weight of isopropanol, or 1-42% by weight of isobutanol may be used. Such phase separation inhibitor is preferably used to lengthen the life of engines. More preferably, when using one or more components selected from butyl cellosolve, ethyl cellosolve or a mixture thereof, it serves as the more excellent phase separation inhibitor.

The isopropanol serves to increase physical miscibility between the compositions by reducing interfacial tension between hydrophilic ethanol as a main fuel source in the present invention and hydrophobic aromatic compounds. The isopropanol may be used in an amount of P43% by weight based on the total weight of the composition.

The butanol may include isomers thereof, e.g. normal butanol, isobutanol, secondary butanol, tertiary butanol and the like. Biobutanol using biomass as an alternative fuel to petroleum is economical in an aspect of securing the raw material since the biobutanol uses wood based raw material which occupies 97% of total vegetable biomass, and is excellent as a transportation fuel since the biobutanol has excellent property as an alternative fuel to gasoline as compared with bioethanol.

Although biobutanol started to be produced using microbial fermentation from early 1990s, it went into decline as the petrochemical industry was rapidly developed at 1950s.

Recently, as an age of high oil prices is fixed, biobutanol is again emerging as a next generation fuel that can substitute petroleum.

The butanol can be more easily stored and transported as compared with existing bio-fuel using ethanol, and still has high thermal efficiency. The reason that the butanol has more advantage than the ethanol is because of its chemical structure. The ethanol is difficult to store and has a critical disadvantage of corroding a transportation pipe. Unlike this, butanol can utilize an existing infrastructure such as a crude oil transportation pipe without installation of additional eguipment.

In the fuel composition for internal combustion engines, butanol contains, as a main conponent, biobutanol derived from biomass. Particularly, since butanol has a lower vapor pressure than ethanol, butanol can be mixed in a higher ratio than ethanol. Also, butanol has low volatility and extremely low discharge amount of soot and smoke.

Butanol can improve the cold start-up property that is a disadvantage of ethanol, and can reduce excessive fuel consumption that is, particularly, a disadvantage of alcohols.

Also, since butanol has high thermal efficiency, it has excellent effect to enhance fuel efficiency and reduce exhaust gas. Further, butanol has the excellent effect of preventing phase separation even though moisture exists in the fuel.

Butanol is particularly advantageous as a fuel for internal combustion engines when used in the range of 188% by weight.

Isobutanol can improve the cold start-up property that is a disadvantage of ethanol and reduce excessive fuel consumption that is, particularly, a disadvantage of alcohols. Also, isobutanol has the excellent effect of enhancing fuel efficiency and reducing exhaust gas. Isobutanol is particularly advantageous as a fuel for internal combustion engines when used in the range of 112% by weight.

Further, the fuel composition of the present invention may further comprise aromatic hydrocarbon mixture in order to increase the fuel efficiency Examples of the aromatic hydrocarbon mixture include Aromatic-100 (available from ExxonMobil), consisting of two or more components selected from ethylbenzene, 1-methyl-3-ethylbenzene, 1,3, 5-trimethylbenzene, 1,2, 4-trimethylbenzene, 1,2, 3-trimethylbenzene, isopropylbenzene, propylbenzene, cumene, 1-ethyl-2-methyl benzene, 1-ethyl-2.4-dimethyl benzene, naphthalene, naphthalene derivatives, indane ard indane derivatives.

Specific examples thereof include those commercially available in the common name of Aromatic-lOO (from ExxonMobil), Hi-Sd 10 (from Ashland mc), Kocosol-100 or Kocosol-l50(from 5K), Techsol-l00(from GS-Caltex), polyethylbenzine, Heavy Aromatic Maphtha, High flash Aromatic, Shelisol R and the like.

In particular, the aromatic hydrocarbon mixture is used to improve ignitability and fuel efficiency. When using in the content of 119% by weight, desired effect of improvement in fuel efficiency can be obtained.

Furthermore, methanol can be obtained from petroleum or coal, but it can also be obtained from natural trees or the like. As such, methanol has an advantage that it can be used as an alternative fuel to petroleum.

The fuel composition for internal combustion engines according to the present invention reduces discharge of air pollutants, and, particularly when using an alcohol component like biobutanol, exhibits the effects of preventing a phase separation, enhancing an octane number and preventing an incomplete combustion, thereby enhancing the fuel efficiency.

Also, the present fuel composition is a novel bio-fuel for internal combustion engines that can reduce the exhaust gas and solve the problem of environmental pollution, e.g. ground water contamination and soil pollutions that are becoming a global problem, and replace the octane number enhancer (tically, MTBF) . Thus, another aspect of the present invention is related to a process for reducing the waste discharge of internal combustion engines and a novel octane number enhancer. The fuel composition for internal combustion engines according to the present invention may be used alone or in a mixture with a kno1⁄2m conventional fuel for internal combustion engines.

In another example of the present invention, bio-diesel may be added to individual embodiment of the invention in the content of O.O185% by weight based on the total weight of the composition. Conventionally, bio-diesel is mainly used in a diesel engine. However, when the bio-diesel is used in a small amount in a gasoline engine, it facilitates lubrication action, thereby giving more excellent effects of enhancing fuel efficiency and increasing the lifetime of engine, when compared with the existing case using gasoline alone. In contrast, when the content of the bio-diesel is exoessive, it is disadvantageous since the bio-diesel is agglomerated to cause the clog of the oil filter of a vehicle, lowering in staring-up performance and reduction in engine power. However, in case of diesel engine, the blo-diesel may be used within the above range since the power is generated due to compressive explosion.

In addition, the fuel composition of the present invention may further include, if necessary, one or more components selected from i-43% by weight of kerosene, i32% by weight of Hi-sene (Transient fuel oil No. 1 produced by Samsung Total Petrochemicals Co., Ltd.) and l36% by weight of Hi-nine (Transient fuel oil No. 2 produced by Samsung Total Petrochemicals Co., Ltd.) Hi-sene is a by-product generated during the course of producing a petrochemical product from naphtha and the condensate as raw materials in a petrochemical plant. Hi-acne comprises heavy components having about *48 carbon atoms. It is registered as Transient fuel oil No. 1 on the basis of the Petroleum and Alternative Fuel Business Act according to Korean Standards (KS), and is commonly referred to

as hi-sene in the relevant field.

Hi-nine(C9-I-) is also a by-product generated during the course of producing a petrochemical product from naphtha as a raw material in a petrochemical plant, which is registered as Transient fuel oil No. 2. Hi-sene and Hi-nine are advantageous in that they are by-products but utilized as an alternative fuel for internal combustion engines. Particularly, Hi-nine has a flow point of -iot and thus can be used without changing temperature especially in winter. Further, Hi-nine contains a small amount of sulfur component, and little sulfur oxides (SOx) is contained in the exhaust gas upon combustion. Hi-sene and Hi-nine are those having significantly reduced sulfur when compared with the light oil and thus are very advantageous as the alternative fuel for internal combustion engines.

According to the present invention, aliphatic alkane or alicyclic alkane having 54O carbon atoms and preferably 626 carbon atoms can be further added in an amount of 1-'85% by weight, if necessary. More specifically, the fuel composition for internal combustion engines includes the component essentially consisting of C5C4O alkanes, derivatives of such alkanes having CIJC2 alkane side chain and derivatives of C5C6 cyclic compound wherein hydrogen is substituted by C1C2 alkane.

Moreover, the fuei composition for internal corrlrnstion engines according to the present invention can be used as an alternative fuel or an additive for gasoline and diesel oil.

When used as an additive, the fuel composition of the present invention provides excellent effects in terms of fuel efficiency, power performance, exhaust gas and noise when compared with a conventional gasoline, regardless of the amount of its addition among the total 100% by weight of gasoline.

Evaluation for the fuel composition for internal combustion engines according to the present invention was conducted according to the European evaluation method (ECE15+EUDC) which is identical with the method described in Korean Patent Registration No. 10-0525362. Unleaded gasoline of octane number #93 was used for comparison. Fuel compositions of Examples 1 to 6 of the present invention that will be described below were used. Herein, an automobile of JETTA FV716OCix available from VCIJKSVAGEN equipped with an ATK engine was used.

Evaluation and analysis were then conducted according to the Measurement methods, G318352.2-2001 (Method for measuring exhaust gas upon driving), GB/T3845-93(Method for measuring exhaust gas upon starting-up), GB/T12543-90 (Method for measuring power performance of an automobile), and GB1495- 2002 (Method for measuring external noise of the automobile at the time of high-speed driving) . That is, after injection of the fuel and driving the automobile to a distance of 200km, exhaust gas upon idling (twice), exhaust gas during driving (once), fuel economy (once), power performance (once) and noise (once) were measured.

[Table 1]

Specification of the vehicle for test

Model of JETTA FV7l600ix Manufacturer of EAW-VW vehicle vehicle Weight of 1130 Running distance 89.787 hr vehicle Gear 5-speed Engine displacement 1.6 Model of ATh Pressure of tire 225k5a engine

[Table 2]

Experimental instruments and devices for test No. Name of device or Model Manufacturer instrument 1 Direct current chassis cTDY-1211 HORIBA, Japan measuring device 2 Constant volume sampling cvs 9100 HORIBA, Japan system 3 System for analyzing MEXA 9400 HORIBA, Japan exhaust of a vehicle 4 Portable device for MEXA 554GE HORIBA, Japan analyzing exhaust gas of a vehicle Ignition timing device 4165 Model US 6 Non-contact spoodmctor LO 5100 GNU SOFEI, Japan 7 Grader HS-5670 National Manufacturer of Instruments in Hong ____ ___________________________ _______________ Seong 8 Grade correction device 55-6080 National Manufacturer of Instruments in Hong ____ ___________________________ _______________ Seong 9 Table of revolution 56-1520 GNU, Japan ____ speed _______________ _________________________ Thermometer SY Convection ONO Manufacturer, Japan 11 Table of direction and DEM5-1 Manufacturer of velocity of wind by a Instruments in Chang magnetic sensor Ohun The results evaluated from component analysis of gasoline and the fuel composition according to the present invention by Korean Institute of Petroleum Quality on the basis of standards for quality of gasoline, are shown in Table 3: [Table_3] _____________________ _____________ _____________ Test item Quality standard of Analysis Analysis gasoline results of results of Regular High gasoline Example 1 grade (regular ___________________ _______________ ___________ gasoline) _________________ Octane 9l-94 More than 92.9 99.6 nurnber(Research 94 Method) Distillation Terrperature Lower than 73 48.1 properties of 13% effiux (C) Terrperature Lower than 125 82.5 of 53% efflux Temperature Lower than 175 154.7 of 93% efflux End point Lower than 225 202.8 Residue Lower than 2.0 1.C (volume%) Water and Lower than 0.01 Less than Less than 0.002 precipitate 0.005 (volume%) Copper plote Lower then 1 1 0.4 corrosion (sot. 3h) Vapor pressure 4496 72.6 69 (37.Bt, kpa) ___________________________ ________________ _________________ Oxidation More than 480 More than 480 More than 480 stability (mm) Residual gum Lower than 5 Less than 1 Less than 1 after washing (mg/ic 3m!) Sulfur powder Lower than 50 13 Less than 0.005 (mg/kg) ___________________________ ________________ _________________ Pb content (g/i) Lower than 0.013 Less than Less than 0.001 0.001 P content (g/1) Lower than 0.0013 Less than Less than 0.0001 0.0001 Total aromatic Lower than 30 16.29 14.7 (volumet) Benzene (voluine3) Lower than 1 0.96 Not detected Olefin(volumei) Lower than 18 14.8 1.0 Oxygen oontent Lower than 0.5-2.3 1.53 2.26 (weight 3) Methanol content Lower than 0.1 Less than 0.01 Not detected (weight 3) Particularly, the result of component analysis by Korea Institute of Petroleum Quality has shown that the fuel composition of the present invention had high octane number (99.6) without separately adding an octane number enhancer.

Particularly, the sulfur content was significantly reduced, while benzene that is critically harmfui to human body was not detected. This can be another advantage of the present invention.

Individual components were mixed together according to the ocmpositicns described below to prepare fuel compositicns for internal combustion engines according to the present invention.

Evaluation for the fuel composition was conducted according to the European evaluation method (ECES5+EUDC) which is identical with the method described in Korean Patent Registration No. 10- 0525362. The results are listed in the Tables below.

Mode for Carrying out the Invention

Examples 1 to 6 and Comparative Examples 1 to 2

[Example 1]

1) 40% by weight of bio-bunanol; 2) 40% by weight of paraffinic hydrocarbon solvent (Solvent No. 1, produced by 5K) and 5% by weight of paraffinic hydrocarbon solvent (Solvent No. 5, produced by SK) 3) 7% by weight of toluene; and 4) 8% by weight of xylene Using a mixed fuel prepared by mixing with the above fuel composition, evaluations of performance were conducted according to the European Evaluation Method (ECE15+EUDC) . The results are listed in the Tables below.

[Example 2]

1) 42% by weight of bio-buoanol; 2) 35%: by weight of hydrocarbon solvent (Solvent Mo. 1) and 7% by weight of hydrocarbon solvent (Solvent No. 5); 3) 9% by weight of toluene; 4) 2% by weight of aromatic hydrooarbon mixture, Techsol- (available from GS Caltex) 5) 2% by weight of isopropanol; 6) 2% by weight of Hi-nine; and 7) 1% by weight of butyl cellosolve.

A mixed fuel was prepared by mixing 10% by weight of the above fuel composition with 90% by weight of 93# unleaded gasoline. Evaluations of performance were then conducted according to the European Evaluation Method (ECE15+EUDC) The results are listed in Tables below.

[Example 3]

1) 40% by weight of bio-bunanol; 2) 40% by weight of paraffinic hydrocarbon solvent (Solvent No. 1, produced by SN) and 5% by weight of paraffinic hydrocarbon solvent (Solvent No. 5, produced by SN) 3) 7% by weight of toluene; and 4) 8% by weight of xylene A mixed fuel was prepared by mixing 40% by weight of the above fuel composition with 60% by weight of 93# unleaded gasoline. Evaluations of performance were then conducted according to the European Evaluation Method (ECE15+EUDC) . The results are listed in Tables below.

[Example 4]

1) 43% by weight of bio-bunanol; 2) 35% by weight of paraffinic hydrocarbon solvent (Solvent No. 1) and 4% by weight of hydrocarbon solvent (Solvent No. 5); 3) 11% by weight of xylene; 4) 2% by weight of aromatic hydrocarbon mixture, Techsol- (available from GS Caltex) 5) 2% by weight of isopropanol; 6) 2% by weight of Hi-nine; and 7) 1% by weight of butyl cellosolve.

Using the above fuel composition, evaluations of performance were conducted according to the European Evaluation Method (ECE15+EUDC) . The results are listed in Tables below.

[Example 5]

1) 42% by weight of bio-bunanol; 2) 35% by weight of hydrocarbon solvent (Solvent No. 1) and 5% by weight of hydrocarbon solvent (Solvent No. 5); 3) 10% by weight of toluene; 4) 2% by weight of aromatic hydrocarbon mixture, Techsol- (available from GS Caltex) 5) 2% by weight of isopropanol; 5) 2% by weight of Hi-sene; and 7) 2% by weight of butyl cellosolve.

Using the above fuel composition, evaluations of performance were conducted according to the European Evaluation Method (ECE15+EUDC) . The results are listed in Tables below.

[Example 6]

1) 40% by weight of bio-bunanol; 2) 40% by weight of paraffinic hydrocarbon solvent (Solvent No. 1, produced by SK) and 4.5% by weight of paraffinio hydrocarbon solvent (Solvent No. 5, produced by SK); 3) 7% by weight of toluene; 4) 8% by weight of xylene; and 5) 0.5% by weight of biodiesel Using a mixed fuel prepared by mixing with the above fuel composition, evaluations of performance were conducted according to the European Evaluation Method (ECE1S+EUDC) . The results are listed in Tables below.

As a result, it has been shown that the effect of lowering exhaust gas discharge and the fuel efficient were noticeable.

[Comparative Example 1] 1) 100% by weight of 93ff unleaded gasoline Using the above gasoline, evaluations of perfornance were conducted according to the European Evaluation Method (ECE15+EUDC) . The results are listed in Tables below.

[Comparative Example 2] 1) 36% by weight of hydrocarbon solvent (Solvent No. 1) and 6% by weight of hydrocarbon solvent (Solvent No. 5); 2) 10 by weight of toluene; 3) 2% by weight of aromatic hydrocarbon mixture, Techsol- 100 (available from GS Caltex) 4) 40% by weight of 93ff unleaded gasoline; 5) 2% by weight of isopropanol; 6) 2% by weight of Hi-nine; and 7) 2% by weight of butyl cellosolve.

Using the above fuel composition, evaluations of performance were conducted according to the European Evaluation Method (ECE15+E%JDC) . The results are listed in Tables below.

[Table 4]

Test Results of exhaust gas during idling of JETTA (VOIJKSVAGEN) automobile Test items Idling speed 00(t) HO(ppm) Example 1 800 0.00 <20 Example 2 800 0.00 <20 Example 3 800 0.00 <20 Example 4 800 0.00 <20 Example 5 800 0.00 <20 Example 6 800 0.00 <20 Example 7 800 0.00 <20 Comparative 800 0.00 <20

Example 1

Comparative 800 0.00 <20

Example 1

The result of the exhaust gas measurement according to the method of G318352.2-2001 has shown that no increase of exhaust gas was found after driving 200 Jn as compared with the exhaust gas at the time of idling. Thus, there was no pollution in exhaust gas at the time of idling, for all cases.

[Table 5]

Test Results of discharge of pollutant and economical efficiency of fuel in JETTA(VOLKSVAGEN) automobile Test items Hc(g/hn) CO(g/km) MDX (g/]an) Fuel cons umpt ion _____________ ___________ ___________ __________ (l/km) Example 1 0.01 0.39 0.06 7.68 Example 2 0.05 0.60 0.16 8.00 Example 3 0.05 0.54 0.14 7.98 Example 4 0.04 0.45 0.09 7.74 Example 5 0.03 0.44 0.08 7.75 Example 6 0.02 0.40 0.06 7.70 Comparative 0.11 0.88 0.28 8.16

Example 1

Corruparative 0.08 0.70 0.19 8.08

Example 1

As can be seen from the above Table, the effects of he lowering of pollutants and the fuel efficiency were noticeable in ease of the composition of Example 1 (containing biobutanol, paraffinic hydrocarbon solvent, toluene and xylene) as compared with that of Comparative Example 1 (unleaded gasoline) Also, the effects of the lowering of pollutants and the fuel efficiency were noticeable in case of the composition of Example 6 (containing biobutanol, paraffinic hydrocarbon solvent, toluerie, xylene and biodiesel) as compared with that of Comparative Example 1 (unleaded gasoline)

[Table 6]

Test Results of power performance of JETTJ&(VOIJKSVAGEN) automobile (unit: see) Test items Duration of Duration of acceleration acceleration to to 5th speed 4th speed Example 1 21.87 19.54 Example 2 24.77 21.92 Example 3 24.66 21.91 Example 4 22.07 20.07 Example 5 22.16 20.08 Example 6 21.79 19.66 Corcuparative 25.98 23.00

Example 1

Comparative 25.20 22.24

Example 1

As can be seen from the above Table, the times required for acceleration to the 4th or 5th speed after driving the distance of 2001an, when using the composition of Example 6 (containing biobutanol, paraffinic hydrocarbon solvent, toluene, xylene and biodiesel) were much faster acceleration force than that reguired in case of using common 93 unleaded gasoline of Comparative Example 1.

The results of measurements of noise at accelerated drivinq of 0ETTA (VOLKSVAGEN) automobile are shoMi in Tables 7- 1 to 7-7 below.

[Table 7-i]

Test results after driving 200 km in comparative_Example 1 Speed Location Engine Engine L/R Medium Maximum revolution revolution mean value value rate rate value (each) 2nd Left 3800 4100 73.4 73.5 73.9 Speed Right 3800 4100 73.6 3nd Left 2800 3050 73.9 74.3 Speed Right 2500 3050 74.6

Background noise 54.6

[Table 7-2]

Test results utter driving 200 Jc in Example 1 Speed Location Engine Engine L/R Medium Maximum revolution revolution mean value value rate rate value _________ __________ ____________ ____________ (each) _________ __________ 2nd Left 3800 4100 71.8 71.3 70.7 Speed Right 3800 4100 70.7 3nd Left 2800 3050 70.0 70.0 Bpeed Right 2800 3050 70.0

Background noise 54.3

[Table 7-3]

Test results after driving 200 Ict in Example 2 Speed Location Engine Engine L/R Medium Maximum revolution revolution mean value value rate rate value _________ __________ ____________ ____________ (each) _________ __________ 2nd Left 3800 4100 73.7 73.4 73.0 Bpeed Right 3800 4100 73.1 3nd Left 2800 3050 72.5 72.6 Speed Right 2800 3050 72.6

Background noise 54.4

[Tabie 7-4] Test results after driving 200 km in Example 3 Speed Location Engine Engine L/R Medium Maximum revolution revolution mean value value rate rate value (each) 2nd Left 3800 4100 72.9 72.3 72.4 Speed Right 3800 4100 71.7 3nd Left 2800 3050 72.3 72.5 Speed Right 2800 3050 72.7

Background noise 54.3

[Tabie 7-5] Test results after driving 200 km in Example 4 Speed Location Engine Engine L/R Medium Maximum revolution revolution mean value value rate rate value (each) 2nd Left 3800 4100 72.5 72.0 72.3 Speed Right 3800 4100 71.4 3nd Left 2800 3050 72.6 72.5 Speed Right 2800 3050 72.4

Background noise 54.4

[Tabie 7-6] Test results after driving 200 km in Example 5 Speed Location Engine Engine L/R Medium Maximum revolution revolution mean value value rate rate value (each) 2nd Left 3800 4100 74.5 73.4 72.4 Speed Right 3800 4100 72.6 3nd Left 2800 3050 71.3 71.3 Speed Right 2800 3050 71.2

Background noise 54.6

[Table 7-7]

Test results after driving 200 km in Example 6 Speed Location Engine Engine L/R Medium Maximum revolution revolution mean value value rate rate value (each) 2nd Left 3800 4100 72.0 72.0 71.6 Speed Right 3800 4100 72.0 3nd Left 2800 3050 71.3 71.1 Speed Right 2800 3050 70.9

Background noise 54.6

As can be seen from the result of noise measurement, the fuel composition according to the present invention exhibited the excellent effect of reducing noise on the whole.

Although the preferred embodiments of the present invention have been described for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims (5)

1. CLAIMS: 1. A fuel composition for internal combusticn engines comprising: a) 1-88% by weight of biobutanol or a mixtnre of biobutanol and butanol, b) 3-75% by weight of paraffinic hydrocarbon solvents, c) 3-45% by weight of tolnene, and d) 6-30% by weight of xylene, based on the total weight of the composition.
2. 2. The fuel composition for internal combustion engines as set forth in claim 1, further comprising one or more components selected from the group consisting of l-'85% by weight of aliphatic alkane and alicyclic alkane having 5 to 40 carbon atoms, 1-43% by weight of kerosens, 1-32% by weight of Hi-sene, l-36% by weight of Hi-nine, 0.1-St by weight of lubricant base oil, 1-9% by weight of butyl cellosolve, 1-lit by weight of ethyl cellosolve, l-l3% by weight of isopropanol, 1-42% by weight of isobutanol and 1-49% by weight of aromatic hydrocarbon mixture, based on the total weight of the composition.
3. 3. The fuel composition for internal combustion engines as set forth in claim 1, further comprising 0.001-6% by weight of rosin, rosin derivatives, and rosin acid or a mixture thereof.
4. 4. The fuel composition for internai combustion engines as set forth in claim 1, further comprising O.Ol-85% by weight of biodiesel.
5. 5. An alternative fuel for internal combustion engines, comprising the fuel composition as set forth in any one of claims 1 to 4 alone or in a mixture with a fuel for internal combustion engines or alcohol fuel.