KR100345016B1 - Fuel compositions - Google Patents

Abstract

A fuel oil composition comprising a major proportion of a liquid hydrocarbon middle distillate fuel oil having a sulphur content of not greater than 0.2 % by weight of the fuel oil and a minor proportion of a hydroxy amine which improves the lubricity of the fuel oil. The inclusion of the hydroxy amine in the fuel also markedly reduces the foaming tendency of the fuel oil.

Description

Fuel composition {FUEL COMPOSITIONS}

U.S. Patent No. 4,409,000 discloses additives for fuels which are conventional liquids that provide purifying power for vaporizers and engines. Mixtures of one or more hydroxy amines with one or more general formulas with one or more hydrocarbon soluble carboxyl-based dispersants are proposed for suppressing sludge formation in vaporizers and engines. The only example relates to the use of such mixtures of components in gasoline as described above. The document only describes the fact that the composition provides the purifying power of the vaporizer and the engine, and no information is disclosed on the properties provided by such a composition.

U.S. Patent No. 2,527,889 discloses polyhydroxy alcohol esters as primary anti-corrosion additives for diesel engine fuels, while U.S. Patent No. 1,505,302 includes, for example, glycerol monoesters and glycerol diesters as diesel fuel additives. An ester mixture is disclosed, and the mixture is described to provide an advantage of reducing wear of the fuel injector, piston ring and cylinder liner.

However, British Patent Application No. 1,505,302 relates to overcoming the operational disadvantages of corrosion and wear caused by acidic combustion product residues in combustion chambers and exhaust systems. The document states that this drawback is due to incomplete combustion under certain operating conditions. Typical diesel fuels available in the literature contain, for example, from 0.5 to 1% by weight sulfur as elemental sulfur, based on the weight of the fuel.

Due to environmental reasons, namely the limitation of sulfur dioxide emissions, the diesel content's sulfur content is lowered or lowered. Therefore, the sulfur content of the heating oil and diesel fuel is limited to a maximum of 0.2% by weight by CEC, and the maximum sulfur content of the diesel fuel in the second stage is 0.05% by weight. During 1996, a full conversion rate of up to 0.05% may be required.

In addition to reducing the sulfur content, the process for producing low sulfur fuels also reduces the content of other fuel components such as polyaromatic components and polar components. Reducing the content of one or more of the sulfur, polyaromatic and polar components in the fuel can cause new problems when using the fuel. That is, by reducing the lubricating power of the fuel to the injection system of the engine, for example, the fuel injection pump may cause a failure relatively early in the engine life, which failure may include, for example, a rotary distributor pump; It occurs in high pressure fuel injection systems such as high pressure rotary distributors, inline pumps, unit injectors and injectors. This severe failure is not due to the corrosive wear described in British Patent Application No. 1,505,302.

As noted above, such failures can occur early in the engine life, whereas the wear problems disclosed in British Patent Application No. 1,505,302 occur later in engine life. Problems arising from using low sulfur diesel fuels are described, for example, in D. Wei and H. Spikes, Wear, Vol. 111, No. 2, p. 217, 1986; And R. Caprotti, C. Bovington, W. Fowler and M. Taylor, SAE Paper 922183; SAE fuels and lubes meeting Oct. 1992; San Francisco, USA.

It is now known that the above wear problems arising from the use of low sulfur fuels can be reduced by adding some additives to the fuel or achieving satisfactory effects. It is also possible to achieve further advantages with the use of the same additives.

The present invention relates to the use of additives to provide low sulfur fuel oils with improved lubricity and other advantages and to fuel oil compositions containing the additives.

According to the present invention, a fuel comprising a middle fraction distillate fuel oil of a liquid hydrocarbon containing 0.2 wt% or less sulfur based on the weight of a fuel oil in large fractions and a small fraction in one or more hydroxy amines of the formula An oil composition is provided:

Where

R ¹ is an alkenyl radical having 4 to 50 carbon atoms (which contains at least one double bond) or an alkyl radical, or a radical of the formula:

[Wherein,

R ² , R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ are independently hydrogen or lower alkyl radicals;

R ⁸ is one alkenyl radical having 4 to 50 carbon atoms (which contains at least one double bond) or an alkyl radical;

R ⁹ is an alkylene radical of 2 to 35 carbon atoms, preferably 2 to 6 carbon atoms;

p, q and v are integers from 1 to 4;

a, b and c may each be 0, one of which is an integer from 1 to 75.]

A second object of the present invention is the use of a fuel oil composition as defined in the first object of the present invention as a compression ignition (diesel) engine fuel for adjusting the wear rate of an engine injection system during engine operation.

A third object of the present invention is a method of operating a compression ignition (diesel) engine comprising providing a fuel oil composition defined in the first object of the present invention as a fuel of an engine to adjust the wear rate of the engine injection system.

Examples herein demonstrate the wear reduction effects of hydroxy amine additives as defined in the first object of the present invention when using fuel oils having a sulfur content of 0.2% by weight or less.

Although not based on theory, in the use of the composition in a compression ignition internal combustion engine, the additives at least partially deposit a monomolecular or multi-molecular layer adhesive on the surface of the injection system, in particular the injection pump moving in contact with each other over the operating conditions of the engine. Wherein the composition is one of: reduced wear, reduced friction, or increased electrical contact resistance in a test when two or more loads are in relative motion under non-hydrodynamic lubrication conditions when compared to a composition that does not contain additives This may cause an abnormality.

It has been found that the inclusion of additives in fuel oils greatly reduces the foaming tendency of the fuel oils, providing the additional advantage that conventionally added defoamers can be reduced or even eliminated.

The features of the invention are described in more detail below.

additive

As noted above, it has been found that the additive may be a single hydroxy amine compound or mixtures thereof and may create at least a partial layer on a particular surface of the engine. This means that the layer formed is not necessarily complete on the contact surface. Thus, the formed layer may apply only a portion of the contact surface area, for example at least 10%, or at least 50%. The formation of such layers and the degree of application of the contact surfaces can be demonstrated, for example, by electrical contact resistance or capacitance.

A test embodiment that can be used to demonstrate one or more of reduced wear, reduced friction or increased electrical contact resistance in accordance with the present invention is the High Frequency Reciprocating Rig test described below.

에 의함) 또는 옥시알킬렌 또는 폴리옥시알킬렌 연결 그룹을 통해 간접적으로(예를 들면, a가 2이상인 경우) 질소 원자에 부착된 하나 이상의 히드록시 알킬 그룹에 의해 제공된다. 히드록시 알킬 그룹 및 임의의 연결 그룹인 옥시알킬렌 단위는 탄소원자 2 내지 6개를 함유할 수 있고, 임의적으로 저급 알킬 라디칼로 치환될 수 있다. "저급" 알킬이란 용어는 탄소수 6 이하의 알킬 그룹을 의미한다. 바람직하게는 p, q 및 v가 존재하는 경우 이들은 1이다.The identified hydroxy amine compounds suitable for use in the present invention may contain R ¹ or R ⁸ groups attached to a nitrogen atom and which are alkyl or alkenyl groups, which contain one or more double bonds, The group contains 4 to 50 carbon atoms, preferably 8 to 30 carbon atoms, more preferably 12 to 25 carbon atoms. The hydroxy functional group is directly moiety (if a is 1 as described above

Is provided by one or more hydroxy alkyl groups attached to a nitrogen atom indirectly (eg when a is 2 or more) or through an oxyalkylene or polyoxyalkylene linking group. The oxyalkylene unit, which is a hydroxy alkyl group and any linking group, may contain 2 to 6 carbon atoms and may be optionally substituted with lower alkyl radicals. The term "lower" alkyl means an alkyl group having 6 or less carbon atoms. Preferably, when p, q and v are present they are 1.

The hydroxyalkyl group and any linking group oxyalkylene unit may together form a chain having up to 75 units, including terminal hydroxy alkyl groups. Preferably the number of oxyalkylene units does not exceed 10. The most preferred number represented by a, b, and c in the structural formula is c, where each of a, b, and c is present.

The radicals R ² , R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ are preferably hydrogen or methyl.

When R ⁹ is present in the structural formula, R ⁹ is preferably an alkylene radical containing 2 to 6 carbon atoms and may be straight or branched chain of carbon atoms.

Suitable hydroxy amines can be prepared by reacting an amine substituted with a suitable R ¹ or R ⁸ with the remaining amine functional groups and an alkylene oxide such as ethylene oxide or propylene oxide. Suitable ethoxyamines are available under the trade names "Ethomeen" and "Ethanolomeen" from Armak Company.

The concentration of hydroxy amine effective to significantly improve the lubricity of the fuel is extremely low and can easily be measured by the abrasion test described in the Examples. Generally, a noticeable reduction in wear is observed using as little additive as on the order of 5 ppm by weight of fuel. Preferred concentrations range from 10 ppm to 0.2% by weight. Higher concentrations may be used, but the wear test should be used to determine the optimal concentration. For economic reasons, the minimum effective amount should be used. Preference is given to concentrations between 25 and 1000 ppm.

A noticeable decrease in the fuel's foaming tendency is observed at lower concentrations of additives, while concentrations as low as 1 ppm can have a significant foaming reduction effect.

Fuel oil

The additives of the present invention are effective when used with heavy nasal distillate fuel oils of liquid hydrocarbons containing up to 0.2% by weight sulfur.

Preferably, the sulfur concentration is 0.05% by weight or less, for example 0.01% by weight or less, and may be as low as 0.005% by weight or 0.0001% by weight or less. The technique describes methods for reducing the sulfur concentration of hydrocarbon distillate fuel oils, such as solvent extraction, sulfuric acid treatment and hydrodesulfurization.

The middle boiling distillate fuel oils to which the present invention can be applied generally boil within a range from about 100 to about 500 ° C, for example from about 150 to about 400 ° C. The fuel oil may comprise atmospheric distillate or vacuum distillate, or a blend of cracked gas oil or any proportion of direct current and pyrolysis and / or catalytic cracking distillate. The most common essential oil distillates are kerosene, injection fuel, diesel fuel, heating oil and heavy fuel oil, and diesel fuel is preferred in the practice of the present invention for the above reasons. The heating oil may be a direct atmospheric distillate or may contain, for example, up to 35% by weight of vacuum gas oil or cracked gas oil or both.

The additive may be incorporated into the bulk fuel oil by methods known in the art. Conveniently, the additive may be incorporated in the form of a concentrate comprising a mixture of additives and a liquid carrier medium that is compatible with the fuel oil, and the additive is dispersed in the liquid medium. This concentrate preferably contains from 3 to 75% by weight, more preferably from 3 to 60% by weight, most preferably from 10 to 50% by weight of additives, preferably in a solution in oil. Examples of carrier liquids include organic solvents including hydrocarbon solvents, such as kerosene fractions such as naphtha, kerosene and heater oils; Aromatic hydrocarbons; Paraffinic hydrocarbons such as hexane and pentane; Alkanols; Isoparaffin; And alkoxyalkanols. The carrier liquid should of course be chosen to be compatible with the additive and the fuel.

Auxiliary additives

The additives of the present invention may be used alone or in a mixture of one or more additives. The additive may be one or more additives known in the art, such as detergents, antioxidants (to prevent fuel degradation), corrosion inhibitors, demulsifiers, mist eliminators, metal deactivators, antifoams, cetane modifiers, co-solvents, package compounds And one or more of the middle boiling distillate cooling flow modifiers.

The following examples illustrate the invention. The results are then tabulated using the following materials and methods.

additive

의 히드록시 아민A. Chemical Formula

Hydroxy amine

fuel

I: middle boiling distillate fuel oil having the following characteristics:

Sulfur content (% by weight) <0.01

Viscosity at 20 ° C. (cSt) 2.486

Density at 15 ° C. (㎏ / dm ³ ) 0.8136

II: Commercial standard kerosene fuel

III: Middle boiling distillate fuel oil having the following characteristics:

Sulfur Content (wt%) 0.18

Viscosity at 20 ° C. (cSt) 4.904

Density at 15 ° C. (㎏ / dm ³ ) 0.8462

Example 1

Additive A is dissolved in Fuel I and Fuel II at various concentrations, and the resulting compositions are described in D. Wei and H. Spikes, Wear, Vol. 111, No. 2, p. 217, 1986; R. Caprotti, C. Bovington, W. Fowler and M. Taylor, SAE paper 922183; SAE fuels and lubes meeting Oct. Tested using a high frequency reciprocating machine (HFRR) described in 1992, San Francisco.

This test is known to provide a measure of the lubricity of the fuel.

HFRR test

The results are expressed in terms of wear tread diameters. In addition, friction coefficients were measured. The tests were conducted at different temperatures as specified. The concentration of the additive used is shown in the following table.

Additive A (Concentration ppm, weight / weight) Friction coefficient Wear mark diameter (mm) 20 ℃ 60 ℃ 20 ℃ 60 ℃ Fuel Ⅰ 050100500 0.480.370.240.22 0.550.380.320.22 0.580.520.380.31 0.670.600.580.42 Fuel II 050100500 0.340.320.260.24 0.350.320.260.24 0.590.530.350.34 0.770.520.500.45

The results show improved lubricity using additive A.

Example 2

Additive A was added to Fuel Oil III at various concentrations and defoaming performance was measured at 0 ° C. The test used was as follows.

Each sample was stirred vigorously for a period of time to observe the time in seconds at which the bubbles collapsed. The results of untreated fuel and treated fuel are compared in the following table.

Additive A Concentration (ppm, weight / weight) Bubble Collapse Time (sec) (average of 2 scales) Fuel Ⅲ 0550500 83.5403515.5

The test results indicate that in the presence of additive A the foaming tendency of the fuel is significantly reduced.

Claims (9)

A fuel oil composition comprising in a large fraction a middle boiling distillate fuel oil of a liquid hydrocarbon containing up to 0.2% by weight of sulfur, based on the weight of the fuel oil, and in a small fraction at least one hydroxy amine of the formula:

Where R ¹ is an alkenyl radical having 12 to 50 carbon atoms (which contains one or more double bonds) or an alkyl radical, or a radical of the formula:

[Wherein, R ² , R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ are independently hydrogen or lower alkyl radicals; R ⁸ is an alkenyl radical having 12 to 50 carbon atoms, which contains one or more double bonds or an alkyl radical; R ⁹ is an alkylene radical having 2 to 35 carbon atoms; p, q and v are each an integer from 1 to 4; a, b and c can each be 0, at least one of which is an integer from 1 to 75. The method of claim 1, A fuel oil composition containing up to 0.05% by weight of sulfur. The method of claim 2, A fuel oil composition containing 0.01% by weight or less of sulfur. The method according to any one of claims 1 to 3, A fuel oil composition, wherein R ¹ or R ^8, when present, is an alkenyl or alkyl radical having 12 to 25 carbon atoms. The method according to any one of claims 1 to 3, a fuel oil composition that is 10 or less when a, b, and c are present. The method according to any one of claims 1 to 3, A fuel oil composition wherein R ² to R ⁷ are hydrogen or methyl. The method according to any one of claims 1 to 3, A fuel oil composition comprising hydroxy amine at a concentration of 1 to 2000 ppm, based on the weight of the fuel oil. The method according to any one of claims 1 to 3, Hydroxy Amine Formula

A fuel oil composition which is a compound of. A method of operating a compression ignition engine comprising adjusting the wear rate of an engine injection system by supplying a fuel oil composition according to claim 1 to the engine fuel.