CN102112587A - Liquid fuel compositions - Google Patents

Abstract

The present invention provides a liquid fuel composition comprising: a base fuel suitable for an internal combustion engine; and one or more poly(hydroxy carboxylic acids) with terminal acid groups having general formula (III) ) Derivatives: [Y-CO[OA-CO] _n -Z _p ] _m -X(III), wherein Y is hydrogen or an optionally substituted hydrocarbon group, A is an optionally substituted divalent hydrocarbon group, and n is 1- 100, m is 1 or 2, Z is an optionally substituted divalent bridging group, p is 0 or 1, and X is a terminal acid group or a group with a terminal acid group, wherein the terminal acid group is selected from carboxyl acid, carboxymethyl, sulfate, sulfonate, phosphate and phosphonate.

Description

liquid fuel composition

technical field

The present invention relates to a liquid fuel composition comprising a substantially base fuel suitable for use in an internal combustion engine, in particular a liquid fuel composition comprising a substantially base fuel suitable for an internal combustion engine and a hyperdispersant.

Background technique

EP 0164817A2 discloses a surfactant suitable for stabilizing solid dispersions in organic liquids and oil/water emulsions, said surfactant comprising Carboxylate or amide of terminal strong acid groups of radicals and phosphonates. A preferred material of this type of surfactant is a poly(hydroxyalkane carboxylic acid) having a strong acid group attached directly or through a linking group to a terminal hydroxyl or carboxylic acid group. The use of such surfactants in fuels is not disclosed therein.

EP 0233684A1 discloses esters or polyesters suitable for use as solid dispersants in organic liquids, said esters or polyesters having: (i) terminal groups containing at least two aliphatic carbon-carbon double bonds, and (ii ) acidic or basic amino group. The use of such surfactants in fuels is not disclosed therein.

GB 2197312A discloses an oil-soluble dispersant additive, wherein the dispersant additive is a poly(C ₅ -C ₉ lactone) adduct prepared by the following process: first make C ₅ -C ₉ lactone and polyamine , polyol, or aminoalcohol to form an intermediate adduct, which is then reacted with an aliphatic hydrocarbyl mono- or dicarboxylic acylating agent having from about 1 to 165 total carbon atoms. The use of said dispersant additives in lubricating oils and fuels is also disclosed in GB2197312A.

EP 0802255A2 discloses hydroxyl-containing acylated nitrogen compounds useful as low chlorine additives for lubricating oils and generally liquid fuels and processes for their preparation.

WO 00/34418 A1 discloses the use of poly(hydroxycarboxylic acid) amide or ester derivatives as lubricity additives in fuel compositions. It is additionally disclosed in WO 00/34418 A1 that it is also possible to achieve one or more effects such as inlet system cleanliness (inlet valves, fuel injectors, carburetors) using poly(hydroxycarboxylic acid) amide or ester derivatives disclosed therein ), combustion chamber cleanliness (remains clean or has a cleaning effect or both in each case), corrosion resistance (including rust prevention), and reduces or eliminates valve sticking.

It has now been found that the use of poly(hydroxycarboxylic acid) derivatives bearing terminal acid groups can also surprisingly provide benefits in improving the lubricity of liquid fuel compositions in which they are incorporated.

Contents of the invention

The present invention provides a kind of liquid fuel composition, and described liquid fuel composition comprises:

- liquid base fuels suitable for use in internal combustion engines; and

- one or more poly(hydroxycarboxylic acid) derivatives with terminal strong acid groups having the general formula (III):

[Y-CO[OA-CO] _n -Z _p ] _m -X (III)

Wherein Y is hydrogen or an optionally substituted hydrocarbon group, A is an optionally substituted divalent hydrocarbon group, n is 1-100, m is 1 or 2, Z is an optionally substituted divalent bridging group, p is 0 or 1, and X is a terminal acid group or a group bearing a terminal acid group, wherein the terminal acid group is selected from the group consisting of carboxylic acid, carboxymethyl, sulfate, sulfonate, phosphate and phosphonate.

The present invention also provides a process for preparing a liquid fuel composition of the present invention comprising mixing one or more poly(hydroxycarboxylic acid) derivatives having terminal acid groups with a base fuel suitable for use in an internal combustion engine.

The present invention also provides a method of operating an internal combustion engine comprising introducing a liquid fuel composition of the present invention into a combustion chamber of the engine.

Detailed ways

The liquid fuel compositions of the present invention comprise a base fuel suitable for use in internal combustion engines and one or more poly(hydroxycarboxylic acid) derivatives having terminal acid groups. Typically, the base fuel suitable for use in an internal combustion engine is gasoline or diesel fuel, and thus the liquid fuel composition of the present invention is typically a gasoline composition or a diesel fuel composition.

The poly(hydroxycarboxylic acid) derivatives with terminal acid groups employed in the present invention may also be referred to as hyperdispersants.

The one or more poly(hydroxycarboxylic acid) derivatives with terminal acid groups in the liquid fuel composition of the present invention is a poly(hydroxycarboxylic acid) derivative with terminal acid groups having the general formula (III) :

[Y-CO[OA-CO] _n -Z _p ] _m -X (III)

Wherein Y is hydrogen or an optionally substituted hydrocarbon group, A is an optionally substituted divalent hydrocarbon group, n is 1-100, m is 1 or 2, Z is an optionally substituted divalent bridging group, p is 0 or 1, and X is a terminal acid group or a group bearing a terminal acid group, wherein the terminal acid group is selected from the group consisting of carboxylic acid, carboxymethyl, sulfate, sulfonate, phosphate and phosphonate.

In the general formula (III), A is preferably a divalent linear or branched hydrocarbon group described below for the general formulas (I) and (II).

That is, in the general formula (III), A is preferably an optionally substituted aromatic, aliphatic or alicyclic linear or branched divalent hydrocarbon group. More preferably, A is an arylene group, an alkylene group or an alkenylene group, especially containing 4-25 carbon atoms, more preferably 6-25 carbon atoms, more preferably 8-24 carbon atoms, more preferably is an arylene, alkylene or alkenylene group of 10-22 carbon atoms and most preferably 12-20 carbon atoms.

Preferably, in said compound of general formula (III), there are at least 4 carbon atoms, more preferably at least 6 carbon atoms, and even more preferably 8-14 carbon atoms directly attached to the carbonyl group and the oxygen derived from the hydroxyl group between atoms.

In compounds of general formula (III), optional substituents in group A are preferably selected from hydroxyl, halogen or alkoxy, especially C _1-4 alkoxy.

In general formula (III) (and general formula (I)), n is 1-100. Preferably, the lower limit of n is 1, more preferably 2, even more preferably 3; preferably, the upper limit of n is 100, more preferably 60, more preferably 40, more preferably 20, and even more preferably is 10 (that is, n can be selected from any of the following ranges: 1-100; 2-100; 3-100; 1-60; 2-60; 3-60; 1-40; 2-40; 3-40; 1 -20; 2-20; 3-20; 1-10; 2-10; and 3-10).

In general formula (III), Y is preferably an optionally substituted hydrocarbyl group as described above for general formula (I).

That is, the optionally substituted hydrocarbyl group Y in the general formula (III) is preferably an aryl, alkyl or alkenyl group containing up to 50 carbon atoms, more preferably 7 to 25 carbon atoms. For example, optionally substituted hydrocarbyl Y may be suitably selected from heptyl, octyl, undecyl, lauryl, heptadecyl, heptadecenyl, heptadecadienyl, stearyl, oleyl, base and linoleyl.

酸钠和苯基甲基苯基。Other examples of said optionally substituted hydrocarbon group Y in general formula (III) herein include: C _4-8 cycloalkyl groups such as cyclohexyl; polycyclic alkyl groups such as polycyclic groups derived from naturally occurring acids such as abietic acid; Terpenyl; aryl such as phenyl; aralkyl such as tolyl; and polyaryl such as naphthyl, biphenyl, paracetamol

Natrate and phenylmethylphenyl.

In the present invention, the optionally substituted hydrocarbon group Y in general formula (III) may contain one or more functional groups, such as carbonyl, carboxyl, nitro, hydroxyl, halogen, alkoxy, amino (preferably tertiary amino (no N-H link)), oxygen, cyano, sulfonyl and sulfinyl. Except for hydrogen, the majority of atoms in a substituted hydrocarbyl group is usually carbon, while heteroatoms (such as oxygen, nitrogen, and sulfur) usually make up only a minority (about 33% or less) of all non-hydrogen atoms present.

Those skilled in the art will appreciate that functional groups such as hydroxyl, halogen, alkoxy, nitro and cyano groups in substituted hydrocarbyl Y will replace one hydrogen atom of the hydrocarbyl, while functional groups such as carbonyl, carboxyl, tertiary amino in substituted hydrocarbyl Y (-N-), oxygen, sulfonyl and sulfinyl will replace the -CH- or _-CH2- moiety of the hydrocarbyl group.

More preferably, the hydrocarbon group Y in general formula (III) is unsubstituted or substituted by a group selected from hydroxyl, halogen or alkoxy, even more preferably C _1-4 alkoxy.

Most preferably, the optionally substituted hydrocarbyl group Y in general formula (III) is stearyl, 12-hydroxystearyl, oleyl or 12-hydroxyoleyl, and those derived from naturally occurring oils such as tall oil group of fatty acids.

In the general formula (III), Z is an optionally substituted divalent bridging group, preferably of the general formula -X ^z -BY ^z _q -, wherein X ^z is selected from oxygen, sulfur or a group of the general formula -NR ¹ - , wherein R ¹ is as described below, B is as described below, Y ^z is selected from oxygen or a group of the general formula -NR ¹ -, wherein R ¹ is as described below, and q is 0 or 1. If q is 1 and both X ^z and Y ^z are groups of the general formula -NR ¹ -, then two R ¹ groups can form a single hydrocarbyl group linking two nitrogen atoms.

Suitably, Z is an optionally substituted divalent bridging group attached to the carbonyl through a nitrogen atom, preferably represented by the general formula (IV):

wherein R ¹ is hydrogen or hydrocarbyl, and B is optionally substituted alkylene.

Examples of hydrocarbyl groups that may represent ^R include methyl, ethyl, n-propyl, n-butyl and octadecyl.

Examples of optionally substituted alkylene groups that may represent B include ethylene, 1,3-propylene, 1,4-butylene and 1,6-hexylene.

Examples of preferred Z moieties in the general formula (III) include -NHCH ₂ CH ₂ -, -NHCH ₂ C(CH ₃ ) ₂ CH ₂ - and -NH(CH ₂ ) ₃ -.

In general formula (III), X is a terminal acid group or a group with a terminal acid group, wherein the terminal acid group is selected from carboxylic acid, carboxymethyl, sulfate, sulfonate, phosphate and phosphonate. If X is a group with a terminal acid group, it is preferably a group of the general formula -Z ¹ -X ¹ , wherein Z ¹ is a bifunctional linking compound, such as a compound selected from polyamines, polyols, hydroxylamines, Or the Z group is as defined above, and ^X is a terminal acid group selected from the group consisting of carboxylic acid, carboxymethyl, sulfate, sulfonate, phosphate and phosphonate; more preferably if X is a terminal acid group with a terminal In the case of an acid group, p is 0 and X is a group of the general formula -Z ¹ -X ¹ in the general formula (III).

The terminal acid group may be present in the free acid form or in the form of a salt of said acid. If the terminal acid group is in the form of a salt, it may conveniently be formed by reacting the terminal acid in the free acid form with a base such as ammonia, organic bases such as amines and aminoalcohols, and inorganic bases. If the acid group in the terminal acid group is a salt, examples of suitable cations include metal cations such as sodium, potassium and calcium and ammonium ions such as ammonium (NH ₄ ⁺ ), N(CH ₃ ) ₄ ⁺ and NH(CH ₃ ) ₄₊ ^.

One or more poly(hydroxycarboxylic acid) derivatives bearing terminal acid groups can be obtained by reaction of:

Poly(hydroxycarboxylic acids) of general formula (I):

Y-CO[OA-CO] _n -OH (I)

wherein Y is hydrogen or optionally substituted hydrocarbyl, A is optionally substituted divalent hydrocarbyl, and n is 1-100;

Carrying groups reactive with terminal carboxylic acid groups of poly(hydroxycarboxylic acids) of general formula (I) and terminal acid groups selected from carboxylic acid, carboxymethyl, sulfate, sulfonate, phosphate and phosphonate compound;

a terminal acid group precursor; or

A bifunctional linking compound that is subsequently reacted with a terminal acid group precursor.

As used herein, the term "hydrocarbyl" denotes a group formed by the removal of one or more hydrogen atoms from a hydrocarbon carbon atom (when multiple hydrogen atoms are removed, not necessarily from the same carbon atom ).

Hydrocarbyl groups can be aromatic, aliphatic, acyclic or cyclic groups. Hydrocarbyl groups are preferably aryl, cycloalkyl, alkyl or alkenyl groups, in which case they may be straight-chain or branched groups.

Representative hydrocarbyl groups include phenyl, naphthyl, methyl, ethyl, butyl, pentyl, methylpentyl, hexenyl, dimethylhexyl, octenyl, cyclooctenyl, methylcyclooctene Dimethylcyclooctyl, ethylhexyl, octyl, isooctyl, dodecyl, hexadecenyl, eicosyl, hexadecyl, triaconyl and phenyl ethyl base.

In the present invention, the term "optionally substituted hydrocarbyl" is used to describe a hydrocarbyl group which optionally contains one or more "inert" heteroatom-containing functional groups. "Inert" means that the functional group does not affect the function of the compound to any appreciable extent.

The optionally substituted hydrocarbyl group Y here in general formula (I) is preferably an aryl, alkyl or alkenyl group having up to 50 carbon atoms, more preferably 7 to 25 carbon atoms. For example, optionally substituted hydrocarbyl Y may be suitably selected from heptyl, octyl, undecyl, lauryl, heptadecyl, heptadecenyl, heptadecadienyl, stearyl, oleyl, base and linoleyl.

酸钠和苯基甲基苯基。Other examples of the optionally substituted hydrocarbyl group Y described herein in general formula (I) include: C _4-8 cycloalkyl groups such as cyclohexyl; polycyclic alkyl groups such as polycyclic groups derived from naturally occurring acids such as abietic acid; Terpenyl; aryl such as phenyl; aralkyl such as benzyl; and polyaryl such as naphthyl, biphenyl, acetaminophen

Natrate and phenylmethylphenyl.

In the present invention, the optionally substituted hydrocarbon group Y may contain one or more functional groups, such as carbonyl, carboxyl, nitro, hydroxyl, halogen, alkoxy, tertiary amino (without N-H linkage), oxygen, cyano, sulfonyl and sulfinyl. Except for hydrogen, the majority of atoms in a substituted hydrocarbyl group is usually carbon, while heteroatoms (eg, oxygen, nitrogen, and sulfur) usually make up only a minority (about 33% or less) of all non-hydrogen atoms present.

Those skilled in the art will appreciate that functional groups such as hydroxyl, halogen, alkoxy, nitro and cyano groups in substituted hydrocarbyl Y will replace one hydrogen atom of the hydrocarbyl, while functional groups such as carbonyl, carboxyl, tertiary amino in substituted hydrocarbyl Y (-N-), oxygen, sulfonyl and sulfinyl will replace the -CH- or _-CH2- moiety of the hydrocarbyl group.

The hydrocarbyl group Y in general formula (I) is more preferably unsubstituted or substituted by a group selected from hydroxyl, halogen or alkoxy, even more preferably C _1-4 alkoxy.

Most preferably, the optionally substituted hydrocarbyl group Y in general formula (I) is stearyl, 12-hydroxystearyl, oleyl, 12-hydroxyoleyl, or derived from naturally occurring oils such as tall oil fatty acid group.

The preparation of poly(hydroxycarboxylic acids) and its derivatives is known and described in the prior art, eg in EP0164817.

Poly(hydroxycarboxylic acids) of general formula (I) can be prepared according to known methods by transesterification of one or more hydroxycarboxylic acids of general formula (II), optionally in the presence of a catalyst:

HO-A-COOH (II)

wherein A is an optionally substituted divalent hydrocarbon group. Said methods are for example described in US 3996059, GB1373660 and GB 1342746.

The chain terminators in the transesterification may be non-hydroxy carboxylic acids.

The hydroxyl group in the hydroxycarboxylic acid and the carboxylic acid group in the hydroxycarboxylic acid or non-hydroxycarboxylic acid may be primary, secondary or tertiary as appropriate.

Transesterification of hydroxycarboxylic acids and non-hydroxycarboxylic acid chain terminators can be carried out by heating the starting materials, optionally in a suitable hydrocarbon solvent, such as toluene or xylene, and azeotroping off the water formed. The reaction may be carried out at a temperature up to -250°C, suitably at the reflux temperature of the solvent.

When the hydroxyl group is in the secondary or tertiary position in the hydroxycarboxylic acid, the temperature employed should not be so high as to dehydrate the acid molecules.

Catalysts for transesterification such as p-toluenesulfonic acid, zinc acetate, zirconium naphthenate or tetrabutyl titanate may be included in order to increase the reaction rate at a given temperature or to decrease the temperature required for a given reaction rate.

In the compounds of the general formulas (I) and (II), A is preferably an optionally substituted aromatic, aliphatic or alicyclic straight-chain or branched divalent hydrocarbon group. Preferably, A is an arylene group, an alkylene group or an alkenylene group, especially containing 4-25 carbon atoms, more preferably 6-25 carbon atoms, more preferably 8-24 carbon atoms, more preferably Arylene, alkylene or alkenylene of 10-22 carbon atoms and most preferably 12-20 carbon atoms.

Preferably, in said compounds of general formula (I) and (II), there are at least 4 carbon atoms, more preferably at least 6 carbon atoms and even more preferably 8-14 carbon atoms directly attached to the carbonyl group and derived from between the oxygen atoms of the hydroxyl group.

In compounds of general formula (I) and (II), optional substituents in group A are preferably selected from hydroxyl, halogen or alkoxy, more preferably C _1-4 alkoxy.

The hydroxyl group in the hydroxycarboxylic acids of the general formula (II) is preferably a secondary hydroxyl group.

Examples of suitable hydroxycarboxylic acids are 9-hydroxystearic acid, 10-hydroxystearic acid, 12-hydroxystearic acid, 12-hydroxy-9-oleic acid (ricinoleic acid), 6-hydroxycaproic acid, preferably It is 12-hydroxystearic acid. Commercial 12-hydroxystearic acid (hydrogenated castor oil fatty acid) typically contains up to 15% by weight of stearic acid and other non-hydroxy carboxylic acids as impurities, and may suitably be applied without further mixing to yield a molecular weight of about 1000-2000 polymers.

When the non-hydroxycarboxylic acid is added to the reaction alone, the ratio required to produce a polymer or oligomer of a given molecular weight can be determined by simple experimentation or by calculation by one skilled in the art.

In compounds of the general formulas (I) and (II), the group (-O-A-CO-) is preferably 12-oxystearyl, 12-oxyoleyl or 6-oxyhexanoyl.

Preferred poly(hydroxycarboxylic acids) of formula (I) to react with amines include poly(hydroxystearic acid) and poly(hydroxyoleic acid).

Suitable groups having terminal carboxylic acid groups reactive with poly(hydroxycarboxylic acids) of general formula (I) and terminal acid groups selected from carboxylic acid, carboxymethyl, sulfate, sulfonate, phosphate and phosphonate Compounds include: α-amino- or α-hydroxy-alkane carboxylic acids, such as glycine and glycolic acid, and amino- and hydroxy-organic sulfonic or phosphonic acids, such as aminoethanesulfonic acid; suitable terminal acid group precursors are phosphorus pentoxide and sulfuryl chloride; and suitable bifunctional linking compounds that can form linking groups between the polyester and the terminal acid groups are polyamines, polyols, hydroxylamines, and Z groups as described above.

Compounds having groups reactive with terminal carboxylic acid groups of poly(hydroxycarboxylic acids) of general formula (I) and terminal acid groups selected from carboxylic acid, carboxymethyl, sulfate, sulfonate, phosphate and phosphonate , a terminal acid group precursor or a difunctional linking compound reacted subsequently with a terminal acid group precursor and the reaction between poly(hydroxy carboxylic acids) of general formula (I) is known, and in the prior art such as EP 0164817 described in.

Preferred poly(hydroxycarboxylic acid) derivatives with terminal acid groups in the present invention are those each having a TBN (Total Base Number) value of less than 60 mg·KOH/g, more preferably less than 50 mg. KOH/g, even more preferably less than 40 mg.KOH/g and most preferably less than 30 mg.KOH/g of material. Suitably, the poly(hydroxycarboxylic acid) derivatives having terminal acid groups each have a TBN value of less than 5 mg.KOH/g, more suitably 2 mg.KOH/g or less, as measured according to ASTM D4739.

Preferred poly(hydroxycarboxylic acid) derivatives with terminal acid groups in the present invention are those each having an acid value of less than 70 mg.KOH/g, more preferably less than 60 mg.KOH/g, even more preferably less than 50 mg.KOH/g. KOH/g and most preferably less than 40 mg.KOH/g of material.

In the liquid fuel composition of the present invention, if the applied base fuel is gasoline, the gasoline may be any gasoline suitable for use in spark ignition (gasoline) type internal combustion engines known in the art. The gasoline used as the base fuel in the liquid fuel composition of the present invention may be appropriately referred to as "base gasoline".

Gasoline usually includes a mixture of hydrocarbons with a boiling range of 25-230°C (EN-ISO 3405), and the optimal boiling range and rectification curve usually vary with the climate and season of the year. The hydrocarbons in gasoline may be obtained by any method known in the art, suitably derived from straight run gasoline, synthetically produced aromatic mixtures, thermally or catalytically cracked hydrocarbons, hydrocracking petroleum distillates, catalytically reformed hydrocarbons, or mixtures of these substances.

The specific distillation curve, hydrocarbon composition, research octane number (RON) and motor octane number (MON) of the gasoline are not critical.

Suitably, the gasoline may have a research octane number (RON) of at least 80, such as 80-110, preferably the gasoline has a RON of at least 90, such as 90-110, more preferably the gasoline has a RON of at least 91, such as 91- 105, the RON of gasoline is even more preferably at least 92, such as 92-103, the RON of gasoline is even more preferably at least 93, such as 93-102, and the RON of gasoline is most preferably at least 94, such as 94-100 ( EN 25164); the motor octane number (MON) of gasoline may suitably be at least 70, such as 70-110, the MON of gasoline is preferably at least 75, such as 75-105, the MON of gasoline is more preferably at least 80, For example 80-100, most preferably the MON of gasoline is at least 82, for example 82-95 (EN 25163).

Generally, gasoline contains components selected from one or more of the following: saturated hydrocarbons, olefins, aromatic hydrocarbons, and oxygenated hydrocarbons. Suitably gasoline may comprise a mixture of saturated hydrocarbons, olefins, aromatics and optionally oxygenated hydrocarbons.

Generally, the olefin content of gasoline is 0-40vol% (ASTM D1319) based on gasoline; preferably, the olefin content of gasoline is 0-30vol% based on gasoline; more preferably, the olefin content of gasoline is 0-20vol% based on gasoline %.

Generally, the aromatics content of gasoline is 0-70vol% (ASTM D1319) based on gasoline; for example, the aromatics content of gasoline is 10-60vol% based on gasoline; preferably, the aromatics content of gasoline is 0-50vol% based on gasoline, For example, the aromatics content of gasoline is 10-50 vol% based on gasoline.

The benzene content of the gasoline is at most 10 vol%, more preferably at most 5 vol%, especially at most 1 vol%, based on gasoline.

Gasoline preferably has a low or ultra-low sulfur content, for example at most 1000 ppmw (parts per million by weight), preferably not more than 500 ppmw, more preferably not more than 100 ppmw, even more preferably not more than 50 ppmw and most preferably not even more than 10 ppmw.

The gasoline also preferably has a low total lead content, such as at most 0.005 g/l, most preferably is lead-free, to which no lead compounds have been added (ie unleaded).

When gasoline contains oxygenated hydrocarbons, at least a portion of the non-oxygenated hydrocarbons will replace the oxygenated hydrocarbons. The oxygen content of gasoline can be up to 35% by weight (EN 1601) based on gasoline (eg alcohol itself). For example, gasoline may have an oxygen content of up to 25 wt%, preferably up to 10 wt%. Suitably, the oxide concentration will have a minimum concentration selected from any of the following: 0, 0.2, 0.4, 0.6, 0.8, 1.0 and 1.2 wt%, and a maximum concentration selected from any of the following: 5, 4.5, 4.0, 3.5 , 3.0 and 2.7 wt%.

Examples of oxygenated hydrocarbons that may be incorporated into gasoline include alcohols, ethers, esters, ketones, aldehydes, carboxylic acids and their derivatives, and oxygen-containing heterocyclic compounds. Preferably, the oxygenated hydrocarbons that can be incorporated into gasoline are selected from alcohols (such as methanol, ethanol, propanol, iso-propanol, butanol, t-butanol and iso-butanol), ethers (preferably containing 5 ethers with 5 or more carbon atoms, such as methyl tert-butyl ether) and esters (preferably esters with 5 or more carbon atoms per molecule); a particularly preferred oxygenated hydrocarbon is ethanol.

When oxygenated hydrocarbons are present in gasoline, the amount of oxygenated hydrocarbons in the gasoline can vary over a wide range. For example, gasolines containing larger proportions of oxygenated hydrocarbons are currently commercially available in many countries such as Brazil and the United States, such as ethanol itself and E85, and gasolines containing smaller proportions of oxygenated hydrocarbons, such as E10 and E5. Thus, gasoline may contain up to 100 vol% oxygenated hydrocarbons. Preferably, the oxygenated hydrocarbons are present in the gasoline in an amount selected from one of the following, depending on the desired final formulation of the gasoline: at most 85 vol %; at most 65 vol %; at most 30 vol %; at most 20 vol %; at most 15 vol %; and at most 10 vol % . Suitably, gasoline may contain at least 0.5, 1.0 or 2.0 vol% oxygenated hydrocarbons.

Examples of suitable gasolines include gasolines with an olefin content of 0-20 vol% (ASTM D1319), an oxygen content of 0-5 wt% (EN 1601), an aromatic content of 0-50 vol% (ASTM D1319) and a benzene content of up to 1 vol%.

Although not critical to the invention, the base gasoline or gasoline composition of the invention may suitably additionally comprise one or more fuel additives. The concentration and nature of the fuel additives which may be included in the base gasoline or gasoline compositions of the present invention are not critical. Non-limiting examples of suitable types of fuel additives that may be included in the base gasoline or gasoline compositions of the present invention include antioxidants, corrosion inhibitors, detergents, dehazers, antiknock additives, metal deactivators, valve seat Dent protector compounds, dyes, friction modifiers, carrier fluids, thinners and marking agents. Suitable examples of these additives are generally described in US 5,855,629.

Suitably, the fuel additive may be blended with one or more diluents or carrier fluids to form an additive concentrate, which may then be mixed with the base gasoline or gasoline composition of the present invention.

The (active matter) concentration of any additive present in the base gasoline or gasoline composition of the invention is preferably at most 1 wt%, more preferably 5-1000 ppmw, advantageously 75-300 ppmw, such as 95-150 ppmw.

In the liquid fuel composition of the present invention, if the applied base fuel is diesel fuel, the diesel fuel used as the base fuel in the present invention is included in automotive compression ignition engines as well as other types of engines such as marine, railway and stationary engines Applied diesel fuel. The diesel fuel used as the base fuel in the liquid fuel composition of the present invention may also be conveniently referred to as "diesel base fuel".

The diesel base fuel may itself comprise a blend of two or more different diesel fuel components, and/or be additive as described below.

These diesel fuels will contain one or more base fuels, which may generally include liquid hydrocarbon middle distillate gas oils, such as petroleum derived gas oils. The boiling points of these fuels are typically in the usual diesel range of 150-400°C, depending on grade and use. Their density at 15°C is usually 750-1000 kg/m ³ , preferably 780-860 kg/m ³ (such as ASTM D4502 or IP 365), and the octane number (ASTM D613) is 35-120, more preferably 40 -85. They usually have an initial boiling point of 150-230°C and a final boiling point of 290-400°C. Their kinematic viscosity (ASTM D445) at 40°C may suitably range from 1.2 to 4.5 mm ² /s.

An example of petroleum derived gas oil is Swedish Group 1 base fuel, defined by Swedish National Specification EC1, having a density of 800-820 kg/ ^m3 at 15°C (SS-EN ISO 3675, SS-EN ISO 12185), T95 320°C or less (SS-EN ISO 3405), and a kinematic viscosity at 40°C of 1.4-4.0 mm ² /s (SS-EN ISO 3104).

Optionally, non-mineral oil based fuels such as biofuels or Fischer-Tropsch derived fuels may also be formed or present in the diesel fuel. These Fischer-Tropsch fuels may for example be derived from natural gas, natural gas liquids, petroleum or shale oil, petroleum or shale oil processing residues, coal or biomass.

The Fischer-Tropsch derived fuel may be used in an amount of 0-100 vol%, preferably 5-100 vol%, more preferably 5-75 vol%, of the whole diesel fuel. For these diesel fuels it may be desirable to contain 10 vol% or more, more preferably 20 vol% or more, still more preferably 30 vol% or more Fischer-Tropsch derived fuel. It is particularly preferred for these diesel fuels to contain 30-75 vol%, and in particular 30 or 70 vol%, of a Fischer-Tropsch derived fuel. The balance of diesel fuel consists of one or more other diesel fuel components.

Such Fischer-Tropsch derived fuel components are any fraction of the middle distillate fuel range which can be separated from (optionally hydrocracked) Fischer-Tropsch synthesis products. Typical fractions will be in the naphtha, kerosene or gas oil boiling range. Fischer-Tropsch products for use in the kerosene or gas oil boiling range are preferred because these products are easy to handle eg in a domestic environment. These products suitably comprise more than 90 wt% of fractions boiling in the range 160-400°C, preferably to about 370°C. Examples of Fischer-Tropsch derived kerosene and gas oil are found in EP-A-0583836, WO-A-97/14768, WO-A-97/14769, WO-A-00/11116, WO-A-00/11117, WO-A-01/83406, WO-A-01/83648, WO-A-01/83647, WO-A-01/83641, WO-A-00/20535, WO-A-00/20534, EP- Described in A-1101813, US-A-5766274, US-A-5378348, US-A-5888376 and US-A-6204426.

Fischer-Tropsch products typically contain greater than 80 wt% and more suitably greater than 95 wt% iso- and n-paraffins and less than 1 wt% aromatics, with the balance being naphthenic compounds. The levels of sulfur and nitrogen will be very low, and generally below the detection limits of these compounds. For this reason, diesel fuel compositions containing Fischer-Tropsch products can be very low in sulfur.

The diesel fuel composition preferably contains no more than 5000 ppmw sulfur, more preferably no more than 500 ppmw, or no more than 350 ppmw, or no more than 150 ppmw, or no more than 100 ppmw, or no more than 70 ppmw, or no more than 50 ppmw, or no more than 30 ppmw, or Not more than 20 ppmw, or most preferably not more than 15 ppmw sulfur.

The diesel base fuel itself can be additived (with additives) or unadditived (without additives). If additiveized, e.g. at a refinery, it will contain small amounts selected from e.g. , lubricant additives, antioxidants and one or more additives for wax anti-settling agents.

Detergent-containing diesel fuel additives are known and commercially available. These additives can be added to diesel fuel in concentrations intended to reduce, remove or slow down the buildup of engine deposits.

Examples of detergents suitable for use in diesel fuel additives for the purposes of the present invention include polyolefin-substituted succinimides or succinamides of polyamines, such as polyisobutylene succinimide or polyisobutenylamine succinamide, aliphatic Amines, Mannich bases or amines and polyolefins (eg polyisobutylene) maleic anhydride. Succinimide dispersant additives are described, for example, in GB-A-960493, EP-A-0147240, EP-A-0482253, EP-A-0613938, EP-A-0557516 and WO-A-98/42808. Particularly preferred are polyolefin-substituted succinimides such as polyisobutylene succinimide.

In addition to detergents, diesel fuel additive mixtures may also contain other components. Examples are: lubricity enhancers; dehazing agents such as alkoxylated phenolic polymers; defoamers such as polyalkane-modified polysiloxanes; ignition improvers (cetane improvers) such as 2-Ethylhexyl nitrate (EHN), cyclohexyl nitrate, di-tert-butyl peroxide and those disclosed in US-A-4208190, column 2, line 27 to column 3, line 21) rust inhibitors (such as propane-1,2-diol half esters of tetrapropenyl succinic acid, or polyol esters of succinic acid derivatives, having 20-500 carbon atoms on at least one alpha carbon atom) Unsubstituted or substituted aliphatic hydrocarbyl derivatives of succinic acid, such as polyisobutylene substituted pentaerythritol diesters of succinic acid); corrosion inhibitors; fragrances; anti-wear additives; antioxidants (such as phenolic plastics such as 2,6-di tert-butylphenol, or phenylenediamine such as N,N'-di-sec-butyl-p-phenylenediamine); metal deactivators; combustion accelerators; antistatic additives; cold flow improvers and Wax anti-settling agent.

Diesel fuel additive blends may contain lubricity enhancers, particularly when the diesel fuel composition has a low (eg, 500 ppmw or less) sulfur content. In the additiveized diesel fuel composition, the lubricity enhancer is suitably present in a concentration of less than 1000 ppmw, preferably 50-1000 ppmw, more preferably 70-1000 ppmw. Suitable commercially available lubricity enhancers include ester and acid based additives. Other lubricity enhancers are described in the patent literature, especially in relation to their use in low-sulfur diesel fuels, for example:

- Paper by Danping Wei and H.A. Spikes: "The Lubricity of Diesel Fuels", Wear, III(1986) 217-235;

- WO-A-95/33805, Cold flow improvers for enhancing the lubricity of low sulfur fuels;

- WO-A-94/17160, Certain esters of carboxylic acids and alcohols as friction-reducing fuel additives in diesel engine injection systems, wherein the acid has 2 to 50 carbon atoms and the alcohol has 1 or more carbon atoms, especially glycerol monooleate and diisodecyl adipate;

- US-A-5490864, certain dithiophosphoric diester diols as anti-wear lubricity additives for low-sulfur diesel fuels; and

- WO-A-98/01516, Certain alkylaromatic compounds having at least one carboxyl group attached to their aromatic nucleus impart antiwear lubricity effects especially in low sulfur diesel fuels.

For diesel fuel compositions it may also be preferred to contain antifoam agents, more preferably in combination with rust and/or corrosion inhibitors and/or lubricity enhancing additives.

If not stated otherwise, the (active matter) concentration of each of said additive components in the additiveized diesel fuel composition is preferably at most 10000 ppmw, more preferably 0.1-1000 ppmw, advantageously 0.1-300 ppmw, such as 0.1-150 ppmw .

The (active matter) concentration of any dehazing agent in the diesel fuel composition is preferably 0.1-20 ppmw, more preferably 1-15 ppmw, still more preferably 1-10 ppmw, advantageously 1-5 ppmw. The (active matter) concentration of any ignition promoter present is preferably 2600 ppmw or less, more preferably 2000 ppmw or less, suitably 300-1500 ppmw. The (active matter) concentration of any detergent in the diesel fuel composition is preferably 5-1500 ppmw, more preferably 10-750 ppmw, most preferably 20-500 ppmw.

In the case of diesel fuel compositions, for example, fuel additive mixtures typically contain detergents and diesel fuel compatible diluents (which may be mineral oil), solvents such as those provided by Shell Solvents sold under the trademark "SHELLSOL", polar solvents such as esters, and especially alcohols (such as hexanol, 2-ethylhexanol, decanol, isotridecyl alcohol) and alcohol mixtures (such as sold by the company Shell under the trade name Substances sold under the name "LINEVOL", especially LINEVOL 79 alcohol (which is a mixture of C _7-9 primary alcohols or a commercially available mixture of C _12-14 alcohols).

The total level of additives in the diesel fuel composition may suitably be from 0 to 10000 ppmw, and preferably below 5000 ppmw.

In the above, the amounts of components (concentration, vol%, ppmw, wt%) are all active substance amounts, ie excluding volatile solvent/diluent substances.

The liquid fuel compositions of the present invention are prepared by mixing one or more poly(hydroxycarboxylic acid) derivatives having terminal acid groups with a base fuel suitable for use in an internal combustion engine. If the base fuel mixed with one or more poly(hydroxycarboxylic acid) derivatives with terminal acid groups is gasoline, the prepared liquid fuel composition is a gasoline composition; similarly, if mixed with one or more The base fuel mixed with the poly(hydroxy carboxylic acid) derivatives with terminal acid groups is diesel fuel, and the prepared liquid fuel composition is a diesel fuel composition.

Preferably, the one or more poly(hydroxycarboxylic acid) derivatives having terminal acid groups are present in the liquid fuel composition of the present invention in an amount of at least 1 ppmw (percentage), based on the total weight of the liquid fuel composition. One ten-thousandth part by weight). More preferably, the amount of one or more poly(hydroxycarboxylic acid) derivatives with terminal acid groups present in the liquid fuel composition of the present invention also complies with one or more of parameters (i) as set forth below- (xx):

(i) At least 10ppmw

(ii) at least 20ppmw

(iii) at least 30ppmw

(iv) at least 40ppmw

(v) at least 50ppmw

(vi) at least 60ppmw

(vii) at least 70ppmw

(viii) At least 80ppmw

(ix) at least 90ppmw

(x) at least 100ppmw

(xi) up to 20 wt%

(xii) up to 18 wt%

(xiii) up to 16 wt%

(xiv) up to 14 wt%

(xv) up to 12 wt%

(xvi) up to 10 wt%

(xvii) up to 8 wt%

(xviii) up to 6 wt%

(xix) up to 4 wt%

(xx) up to 2 wt%

Suitably, one or more poly(hydroxycarboxylic acid) derivatives having terminal acid groups may also be present in the liquid fuel composition of the present invention in an amount of at least 200 ppmw, at least 300 ppmw, at least 400 ppmw, at least 500 ppmw, or Even at least 1000ppmw.

Surprisingly, it has been found that the use of one or more poly(hydroxycarboxylic acid) derivatives with terminal acid groups in a liquid fuel composition has a significant effect in improving the lubricity of the liquid fuel composition relative to the liquid base fuel Significant benefits can be provided, especially when the liquid fuel composition is gasoline.

The term "improved/improved lubricity" as used herein means that wear scars are reduced using high frequency reciprocating equipment (HFRR).

It has also been found that the use of one or more poly(hydroxycarboxylic acid) derivatives with terminal acid groups in a liquid fuel composition is also effective in the liquid fuel of the present invention relative to an internal combustion engine fueled by a liquid base fuel. The composition provides benefits in terms of engine cleanliness of fueled internal combustion engines, particularly in terms of improved intake valve deposit cleanliness and/or injector nozzle cleanliness performance.

The term "improved/improved cleaning of intake valve deposits" means that, relative to a base fuel that does not contain one or more poly(hydroxycarboxylic acid) derivatives with terminal acid groups, The weight of the sediment formed on it is reduced.

The term "improved/improved injector nozzle cleanliness" means that the amount of deposits formed on the injector nozzles of the engine is reduced, as measured by the torque loss of the engine.

It has also been found that the use of one or more poly(hydroxycarboxylic acid) derivatives with terminal acid groups in liquid fuel compositions can also be used to improve the performance of the present invention relative to internal combustion engines fueled by liquid base fuels. Liquid fuel compositions provide benefits in terms of fuel economy for fueling internal combustion engines.

The present invention therefore also provides a method of improving the lubricity of liquid base fuels suitable for use in internal combustion engines, comprising combining one or more poly(hydroxycarboxylic acid) derivatives with terminal acid groups with most a liquid base fuel blend for an internal combustion engine; a method of improving the intake valve deposit cleaning performance of a liquid base fuel suitable for use in an internal combustion engine, the method comprising making one or more poly(hydroxycarboxylic acids) with terminal acid groups Derivatives mixed with most liquid base fuels suitable for internal combustion engines; a method of improving the cleanliness of injector nozzles for liquid base fuels suitable for internal combustion engines, said method comprising making one or more based poly(hydroxy carboxylic acid) derivatives are mixed with most liquid base fuels suitable for internal combustion engines; A variety of poly(hydroxycarboxylic acid) derivatives with terminal acid groups are blended with most liquid base fuels suitable for internal combustion engines.

In addition, the use of one or more poly(hydroxycarboxylic acid) derivatives with terminal acid groups in liquid fuel compositions can also be used in improving the liquid fuel of the present invention relative to internal combustion engines fueled by liquid base fuels. The compositions provide benefits in terms of lubricant performance for fueling internal combustion engines.

In particular, improved lubricant performance in internal combustion engines fueled with the liquid fuel compositions of the present invention can be observed by reduced amounts of sludge and varnish on certain engine components, such as rocker arm covers, cam guards, timing chain covers, Sludge on oil pan, oil pan baffles and valve covers, and varnish on piston skirts and cam baffles.

In particular, the use of one or more poly(hydroxycarboxylic acid) derivatives with terminal acid groups in gasoline compositions can inhibit the use of gasoline compositions of the present invention relative to internal combustion engines fueled by gasoline base fuels. Provides benefits in terms of specific sludge and varnish deposit formation (as measured by ASTM D6593-07) for fueled internal combustion engines.

Accordingly, the present invention also provides a method of improving the performance of a lubricant for an internal combustion engine, said method comprising using a liquid fuel composition of the present invention as a fuel for an internal combustion engine comprising an engine lubricant.

The invention also provides a method of operating an internal combustion engine comprising introducing a liquid fuel composition of the invention into a combustion chamber of the engine.

The aforementioned poly(hydroxycarboxylic acid) derivatives having terminal acid groups may also be suitably used in lubricating compositions, especially automotive engine lubricating oil compositions. WO 2007/128740, incorporated herein by reference, discloses suitable lubricating base oils and additives into which the poly(hydroxycarboxylic acid) derivatives with terminal acid groups described above may be mixed.

Therefore, the present invention also provides a lubricating composition comprising:

- base oils; and

- Poly(hydroxycarboxylic acid) derivatives as described above bearing terminal acid groups.

Typically, the poly(hydroxycarboxylic acid) derivatives with terminal acid groups are present in the lubricating compositions of the present invention in an amount of 0.1-10.0 wt%, more preferably 0.1-5.0 wt%, based on the total weight of the lubricating composition wt%. According to a particularly preferred embodiment, said composition comprises, based on the total weight of the lubricating composition, less than 5.0 wt%, preferably less than 2.0 wt%, of poly(hydroxycarboxylic acid) derivatives bearing terminal acid groups.

Typically, the lubricating composition has a relatively low phosphorus content, such as less than 0.12 wt% (as measured by ASTM D 5185). Preferably, the phosphorus content of the composition is less than 0.08 wt%. Preferably, the phosphorus content of the composition is higher than 0.06 wt%.

Additionally, it is preferred that the composition has a sulfur content of less than 0.6 wt% (measured according to ASTM D 5185).

It is further preferred that the composition has a chlorine content of less than 200 ppm (as measured by ASTM D 808).

According to a particularly preferred embodiment, the composition has an ash content of less than 2.0% by weight (measured according to ASTM D 874).

According to a particularly preferred embodiment of the invention, the composition comprises a zinc dialkyldithiophosphate (ZDDP) compound. Typically, if present, the ZDDP compound is present in an amount of 0.01-1.5 wt%, preferably 0.4-1.0 wt%. ZDDP compounds can be made from primary, secondary, tertiary alcohols or mixtures thereof preferably containing less than 12 carbon atoms. Preferably, ZDDP compounds are made from secondary alcohols containing 3-8 carbon atoms.

The base oil used in the lubricating composition is not particularly limited, and various conventional mineral oils, synthetic oils and naturally derived esters such as vegetable oils can be suitably used.

The base oil employed may suitably comprise a mixture of one or more mineral oils and/or one or more synthetic oils; thus, the term "base oil" may refer to a mixture comprising various base oils. Mineral oils include liquid petroleum and solvent-treated or acid-treated paraffinic, naphthenic or mixed paraffinic/naphthenic mineral lubricating oils which may be further refined by hydrofinishing processes and/or dewaxing.

Suitable base oils for use in the lubricating oil composition are Group I-III mineral base oils, Group IV polyalphaolefins (PAO), Group II-III Fischer-Tropsch derived base oils, and mixtures thereof.

"Group I", "Group II", "Group III" and "Group IV" base stocks refer to lubricating oil base stocks as defined by the American Petroleum Institute (API) for classes I-IV. These API classifications are defined in API Publication 1509, 16th Edition, Annex E, April 2007.

Fischer-Tropsch derived base oils are known in the art. The term "Fischer-Tropsch derived" means that the base oil is or is derived from a synthetic product of the Fischer-Tropsch process. Fischer-Tropsch derived base oils may also be referred to as GTL (gas-to-liquid) base oils. Suitable Fischer-Tropsch derived base oils which may suitably be used as base oils in lubricating compositions are those described for example in EP 0776959, EP 0668342, WO 97/21788, WO 00/15736, WO 00/14188, WO 00/14187, Substances disclosed in WO 00/14183, WO 00/14179, WO 00/08115, WO 99/41332, EP 1029029, WO 01/18156 and WO 01/57166.

Synthetic oils include hydrocarbon oils such as olefin oligomers (including polyalphaolefin base oils; PAOs), dibasic acid esters, polyol esters, polyalkylene glycols (PAGs), alkylnaphthalenes, and dewaxed waxes isomer. Synthetic hydrocarbon base oils sold under the trade name "Shell XHVI" (trade mark) by the Shell Group may suitably be used.

Polyalphaolefin base oils (PAOs) and their preparation are well known in the art. Preferred polyalphaolefin base oils that may be employed in lubricating compositions may be derived from linear _C2 - _C32 , preferably _C6 - _C16 alpha-olefins. Particularly preferred starting materials for the polyalphaolefins are 1-octene, 1-decene, 1-dodecene and 1-tetradecene.

The total amount of base oil contained in the lubricating composition is preferably 60-99 wt%, more preferably 65-98 wt%, and most preferably 70-95 wt%, based on the total weight of the lubricating composition.

Preferably, the finished lubricating composition has a kinematic viscosity at 100°C of 2-80 mm ² /s, more preferably 3-70 mm ² /s, most preferably 4-50 mm ² /s.

The lubricating composition may also contain further additives such as anti-wear additives, antioxidants, dispersants, detergents, friction modifiers, viscosity index improvers, pour point depressants, corrosion inhibitors, defoamers and sealants or Seal Compatibility.

Since these and other additives are well known to those skilled in the art, they will not be discussed in further detail here. Specific examples of these additives are described, for example, in Kirk-Othmer Encyclopedia of Chemical Technology, Third Edition, Vol. 14, pp. 477-526.

Accordingly, the detergent, if present, is preferably selected from phenate and sulphonate detergents.

The lubricating composition may be suitably prepared by mixing the above-mentioned poly(hydroxycarboxylic acid) derivatives with terminal acid groups and optionally any other additives normally present in lubricating compositions (for example as previously described) with minerals and / or synthetic base oil preparation.

The use of the aforementioned poly(hydroxycarboxylic acid) derivatives with terminal acid groups in lubricating compositions can provide advantages in terms of improved lubricity of the lubricating composition.

In addition, the use of the aforementioned poly(hydroxycarboxylic acid) derivatives with terminal acid groups in lubricating compositions can provide advantages in inhibiting the formation of certain sludge and varnish deposits as measured by ASTM D 6593-07.

In addition, the use of the aforementioned poly(hydroxycarboxylic acid) derivatives with terminal acid groups in lubricating compositions can provide advantages in improving the fuel economy of internal combustion engines lubricated by the lubricating compositions.

The present invention is further understood by the following examples. All amounts and concentrations disclosed in the examples are by weight of the fully formulated fuel composition, if not otherwise indicated.

Example

In the following examples, the commercially available hyperdispersant CH-2C obtained from Shanghai Sanzheng Polymer Material Co Ltd (China) was used.

CH-2C hyperdispersant has an average molecular weight of 1368, a measured sulfur content of 0.61 ppmw, a measured nitrogen content of 0.05 wt%, and a general chemical structure of the type given in Figure 1 below:

Figure 1: Chemical structure of CH-2C

Examples 1-21 and Comparative Examples A-D

The CH-2C hyperdispersants described above were blended in varying amounts into base fuels selected from gasoline, diesel, GTL diesel, and Swedish Group I diesel base fuels as described in Tables 1 and 2 below.

Table 1 Diesel base fuel

parameters Diesel A Diesel B ^a Diesel C ^b Cetane number (ASTMD613) 52.80 ＞76 53.10 Density at 15°C (IP365) 0.84g/ ^cm3 0.78g/ ^cm3 0.82g/ ^cm3 Flash point (IP34) 62.0℃ 104.0℃ 72.5°C Initial boiling point (IP123) 168.6°C 211.0℃ 190.3°C

10% rectification (IP123) 201.3℃ 251.3°C 203.4°C 20% rectification (IP123) 223.9°C 262.4°C 211.1°C 30% rectification (IP123) 246.3°C 273.3°C 225.9°C 40% rectification (IP123) 266.7°C 285.6°C 225.9°C 50% rectification (IP123) 281.8°C 297.3°C 234.2°C 60% rectification (IP123) 293.9°C 307.6°C 242.2°C 70% rectification (IP123) 306.0℃ 316.9°C 250.6°C 80% rectification (IP123) 319.7°C 326.9°C 259.4°C 90% rectification (IP123) 337.2°C 339.1°C 270.5°C 95% rectification (IP123) 350.8°C 348.6°C 279.5°C Final boiling point (IP123) 362.3°C 355.3°C 291.6°C Viscosity at 40°C (IP71) 2.74mm ² /s 3.54mm ² /s 1.94mm ² /s Sulfur content 8.4mg/kg ^c ＜3mg/kg ^c ＜3mg/ ^kgd Total aromatics (IP391/01/IP548/07) 40.5m/m% 0.4m/m% 13.3m/m%

a-Fischer-Tropsch (GTL) derived diesel fuel

b-Swedish Group I diesel fuel

c-ISO 20884

d-ISO 20846

Table 2 Gasoline base fuel

parameters "gasoline" RON value (ASTM D2699) 96.00 MON value (ASTM D2700) 85.10 Density at 15°C (IP365) 0.73g/ ^cm3 Initial boiling point (IP123) 26.5°C 10% rectification (IP123) 37.9°C

20% rectification (IP123) 48.9℃ 30% rectification (IP123) 61.0℃ 40% rectification (IP123) 74.4°C 50% rectification (IP123) 88.2°C 60% rectification (IP123) 101.4°C 70% rectification (IP123) 113.3°C 80% rectification (IP123) 127.9°C 90% rectification (IP123) 149.2°C 95% rectification (IP123) 164.7°C Final boiling point (IP123) 191.2°C RVP*(IP394) 87.8kPa Olefins (including dienes) 16.40vol% Aromatics 28.88vol%

To evaluate the lubricity of the above liquid fuel compositions, the following test procedure was applied.

The lubricity of diesel fuel compositions is determined using the HFRR test described in ISO 12156-1.

The lubricity of gasoline compositions is determined using the adjusted HFRR test. The adjusted HFRR test is based on ISO 12156-1, applying the PCS meter HFRR and supplementing the PCS meter gasoline conversion package, and applying a fluid volume of 15.0ml (+/-0.2ml), a fluid temperature of 25.0°C (+/-1°C), And where the test sample is covered with a PTFE cover to minimize evaporation.

The lubricity test results are given in Table 3 below.

Table 3 HFRR Results for Base Fuel and Fuel Compositions of the Invention

Example base fuel Hyperdispersant (concentration) Average HFRR wear scar (μm) A* Diesel A - 366.5 1 Diesel A CH-2C(50ppmw) 328 2 Diesel A CH-2C(100ppmw) 330.5 3 Diesel A CH-2C(500ppmw) 355

4 Diesel A CH-2C(1000ppmw) 361.5 5 Diesel A CH-2C(1wt%) 229.5 6 Diesel A CH-2C(10wt%) 221 B* Diesel B - 624 7 Diesel B CH-2C(500ppmw) 439 8 Diesel B CH-2C(1000ppmw) 422 9 Diesel B CH-2C(1wt%) 237.5 10 Diesel B CH-2C(10wt%) 209 C* Diesel C - 624.5 11 Diesel C CH-2C(100ppmw) 621.5 12 Diesel C CH-2C(500ppmw) 392.5 13 Diesel C CH-2C(1000ppmw) 400 14 Diesel C CH-2C(1wt%) 219.5 15 Diesel C CH-2C(10wt%) 219.5 D* gasoline - 907 16 gasoline CH-2C(50ppmw) 536 17 gasoline CH-2C(100ppmw) 366.5 18 gasoline CH-2C(500ppmw) 335 19 gasoline CH-2C(1000ppmw) 323.5 20 gasoline CH-2C(1wt%) 258.5 twenty one gasoline CH-2C(10wt%) 252

* - not the invention

From the results in Table 3, it can be seen that the fuel compositions containing CH-2C hyperdispersant (gasoline and diesel fuel compositions) observed reduced wear scars in the HFRR test compared to the base fuel, which indicates that the Lubricity improvement of fuels containing hyperdispersants based on base fuels.

Claims (11)

1. A liquid fuel composition comprising: - base fuels suitable for internal combustion engines; and - one or more poly(hydroxycarboxylic acid) derivatives with terminal acid groups having the general formula (III): [Y-CO[OA-CO] _n -Z _p ] _m -X (III) Wherein Y is hydrogen or an optionally substituted hydrocarbon group, A is an optionally substituted divalent hydrocarbon group, n is 1-100, m is 1 or 2, Z is an optionally substituted divalent bridging group, p is 0 or 1, and X is a terminal acid group or a group bearing a terminal acid group, wherein the terminal acid group is selected from the group consisting of carboxylic acid, carboxymethyl, sulfate, sulfonate, phosphate and phosphonate. 2. The liquid fuel composition of claim 1, wherein based on the total weight of the liquid fuel composition, one or more poly(hydroxycarboxylic acid) derivatives with terminal acid groups in the liquid fuel composition of the present invention It is present in an amount of at least 1 ppmw. 3. The liquid fuel composition of claim 2, wherein based on the total weight of the liquid fuel composition, one or more poly(hydroxycarboxylic acid) derivatives with terminal acid groups in the liquid fuel composition of the present invention Existing amount is 10ppmw-20wt%, 4. The liquid fuel composition of any one of claims 1-3, wherein X is a group of the general formula -Z ¹ -X ¹ , wherein Z ¹ is a bifunctional linking compound, and X ¹ is a terminal acid selected from Groups: carboxylic acid, carboxymethyl, sulfate, sulfonate, phosphate and phosphonate. 5. The liquid fuel composition of claim 4, wherein Z ¹ is a bifunctional linking compound selected from polyamines, polyols, hydroxylamines, or the Z group is as defined in claim 1 . 6. The liquid fuel composition of any one of claims 1-5, wherein the terminal acid groups are in free acid form. 7. The liquid fuel composition of any one of claims 1-5, wherein said terminal acid group is in the form of a salt of said acid. 8. The liquid fuel composition of any one of claims 1-7, wherein the base fuel is gasoline. 9. The liquid fuel composition of any one of claims 1-7, wherein the base fuel is diesel fuel. 10. A method of operating an internal combustion engine, the method comprising introducing a liquid fuel composition according to any one of claims 1 to 9 into a combustion chamber of the engine. 11. A lubricating composition comprising: - base oils; and - one or more poly(hydroxycarboxylic acid) derivatives with terminal acid groups having the general formula (III): [Y-CO[OA-CO] _n -Z _p ] _m -X (III) Wherein Y is hydrogen or an optionally substituted hydrocarbon group, A is an optionally substituted divalent hydrocarbon group, n is 1-100, m is 1 or 2, Z is an optionally substituted divalent bridging group, p is 0 or 1, and X is a terminal acid group or a group bearing a terminal acid group, wherein the terminal acid group is selected from the group consisting of carboxylic acid, carboxymethyl, sulfate, sulfonate, phosphate and phosphonate.