[0001] This invention relates to fuel oil compositions and more especially to fuel oil compositions
containing cracked components which are stabilized against sediment formation and
colour development during storage. Cracked components are frequently included to give
higher yields of diesel fuel and heating oil.
[0002] However, when diesel and heating oils containing cracked components are stored at
ambient or elevated temperatures in air they become discoloured and precipitate sludge
or sediment.
[0003] It is clear that the problem of discoloration and sediment formation is exacerbated
by the presence of cracked components in the fuel. This is demonstrated by the results
in Table 1 which show the amount of sediment formed and the colour change when various
fuel blends are tested in the AMS 77.061 accelerated stability test. Published research
(see, for example, Offenhauer et. al, Industrial and Engineering Chemistry, 1957,
Volume 49, page 1265, and the Proceedings of the 2nd International Conference on the
Long Term Stability of Liquid Fuels, San Antonio, Texas, published October 1986) suggests
that discoloration and sediment result from the oxidation of sulphur and nitrogen
compounds present in the fuel. The analysis of cracked components is consistent with
this. The results in Table 2 show that cracked components contain significantly larger
quantities of nitrogen and sulphur than straight distillates. Also, the addition of
nitrogen and sulphur compounds to a stable straight distillate causes an increase
in both sediment and colour in the AMS 77.061 test (Table 3) with the worst result
being obtained when both nitrogen and sulphur compounds are present in the fuel.
[0004] We have found that sediment and colour formation in distillate fuels which are stored
at ambient temperatures for long periods may be reduced by the addition of certain
quaternary ammonium compounds.
[0005] There are several patents which disclose the use of quaternary ammonium compounds
in liquid fuels. Most of these patents disclose the use of quaternary ammonium compounds
in which the sum total of carbon atoms in the cation exceeds 10. For example, U.S.
Patents Nos. 3,008,813, 3,265,474, 3,397,970 and 3,346,353 all disclose the use of
quaternary ammonium compounds containing the cation:
[R
2NMe
2]
(+)
where R is C
12 to C
14, as agents for improving the water tolerance of hydrocarbon oils.
[0006] U.S. Patents Nos. 3,033,665, 3,158,647 and 3,493,354 disclose the use of quaternary
ammonium compounds for various purposes, as do GB-A-973,826, 1,078,497, 1,392,600
and 1,409,019.
[0007] A number of patents disclose the use of quaternary ammonium compounds in which the
total number of carbon atoms in the cation is less than 10. Two of the patents, GB-A-1,199,015
and 1,221,647, disclose the use of quaternary ammonium phosphates and thiophosphates.
However phosphorus "poisons" transition metal catalysts such as are commonly used
as particulate traps in e.g. diesel engines. A third patent, GB-A-1,432,265, describes
quaternary ammonium compounds to be used in combination with a sulphone polymer as
an antistatic additive.
[0008] U.S. Patent No. 2,633,415 describes the use of an aromatic amino compound or a phenol
in combination with a quaternary ammonium oxide to stabilize gasolines in storage.
[0009] DE-B-1,021,525 describes the use of amine salts to inhibit sludge formation in heating
and diesel fuel oils.
[0010] U.S. Patent No. 3,102,797 describes diquaternary ammonium chlorides for use in fuel
oils as detergents and to impart oxidative stability.
[0011] U.S. Patent No. 3,361,546 describes protecting fuel oils against microbial attack
by incorpoating an additive having a disubstituted naphthalene-based anion, which
is the active part of the molecule, and a quaternary ammonium cation.
[0012] EP-A-293,192 is concerned with reducing deposits in a diesel engine, and discloses
incorporating an oil soluble quaternary ammonium salt in the fuel.
[0013] The present invention provides a fuel composition comprising a fuel oil obtained
by the cracking of heavy oil and a quaternary ammonium compound which is soluble in
the fuel and which comprises a hydrocarbyl cation in which the ratio of carbon atoms
to quaternary nitrogen atoms is not more than 10:1 and an anion which is derived from
an acid which is a carboxylic acid, carboxylic acid anhydride, a phenol, a sulphurized
phenol or a sulphonic acid. The hydrocarbyl group or groups optionally carries or
carry a tertiary amino nitrogen atom or atoms but is or are otherwise unsubstituted.
[0014] Advantageously, the quaternary ammonium compound contains 1 to 4 quaternary nitrogen
atoms, and not more than 10 carbon atoms.
[0015] The quaternary ammonium compounds are effective fuel stabilizers in the absence of
any other additive. Furthermore, the quaternary ammonium compounds are more effective
as fuel stabilizers than quaternary ammonium compounds in which the ratio of carbon
atoms to quaternary nitrogen atoms in the cation exceeds 10.
[0016] Examples of suitable compounds are
1) Quaternary ammonium compounds in which the structure of the cation is:
[R1R2R3R4N]+
in which R1, R2, R3, R4 are alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, alkaryl or aralkyl groups such
that the sum total of carbon atoms in the cation does not exceed 10.
Examples of such cations include tetramethylammonium, ethyltrimethylammonium, n-propyltrimethylammonium,
iso-propyltrimethylammonium, n-butyltrimethylammonium, pentyltrimethylammonium, hexyltrimethylammonium,
heptyltrimethylammonium, phenyltrimethylammonium, o-tolyltrimethylammonium, m-tolyltrimethylammonium,
p-tolyltrimethylammonium, benzyltrimethylammonium, diethyldimethylammonium, di-n-propyldimethylammonium
and di-n-butyldimethylammonium.
2) Quaternary ammonium compounds in which the structure of the cation is:
- where R5 and R6 are alkyl, cycloalkyl, alkenyl, or cycloalkenyl and may be the same or different
but are such that the total number of carbon atoms in the cation does not exceed 10.
Examples of such cations include methylpyridinium, ethylpyridinium, methyl-2-picolinium,
methyl-3-picolinium and methyl-4-picolinium.
3) Quaternary ammonium compounds in which the structure of the cation is:
- where R7 is alkyl, cycloalkyl, alkenyl, cycloalkenyl
- where R8 is nothing, when n = 1, or alkyl, cycloalkyl, alkenyl or cycloalkenyl, when n = 2,
such that the ratio of carbon atoms in the cation to quaternary nitrogen atoms does
not exceed 10:1.
Examples of such cations are the cations in which R
7 = methyl, R
8 is absent, and n = 1, and in which R
7 = R
8 = methyl, and n = 2.
4) Quaternary ammonium compounds in which the structure of the cation is:
[R9R10R11R12N4(CH2)6]m(+)
- where R9 is alkyl, cycloalkyl, alkenyl, cycloalkenyl
- where R10, R11, R12 can be nothing, or alkyl, cycloalkyl, alkenyl, cycloalkenyl such that the ratio of
carbon atoms in the cation to quaternary nitrogen atoms does not exceed 10:1
- m is 1 to 4, the value of m being increased from unity by one for each of R10, R11, R12, having a meaning other than zero.
Examples of such cations are:
[(CH
3)
pN
4(CH
2)
6]
p(+)
where p is 1, 2, 3 or 4.
[0017] It will be understood that in compounds containing two or more quaternary nitrogen
compounds the linkages between them will also be hydrocarbyl groups, i.e., the cation
consists of quaternary nitrogen, carbon and hydrogen atoms, optionally substituted
by tertiary amino nitrogen atoms.
[0018] Cations in groups (3) and (4) when R
8, or one or more of R
10, R
11, R
12, represent zero are examples of hydrocarbyl groups carrying tertiary amino nitrogen
atoms.
[0019] The acid which is used to form the anion may be a carboxylic acid, carboxylic acid
anhydride, phenol, sulphurized phenol or sulphonic acid.
[0020] The carboxylic acid may be e.g.:
i) An acid of the formula
R13-COOH
where R13 is hydrogen, alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkaryl, aralkyl, or aryl.
Examples of such acids include formic acid, acetic acid, propionic acid, butyric acid,
valeric acid, palmitic acid, stearic acid, cyclohexanecarboxylic acid,
2-methylcyclohexanecarboxylic acid, 4-methylcyclohexane carboxylic acid, oleic acid,
linoleic acid, linolenic acid, cyclohex-2-eneoic acid, benzoic acid, 2-methylbenzoic
acid, 3-methylbenzoic acid, 4-methylbenzoic acid, salicylic acid, 2-hydroxy-4-methylbenzoic
acid,
2-hydroxy-4-ethylsalicylic acid, p-hydroxybenzoic acid, 3,5-di-tert-butyl-4-hydroxybenzoic
acid, o-aminobenzoic acid, p-aminobenzoic acid, o-methoxybenzoic acid and p-methoxybenzoic
acid.
ii) A dicarboxylic acid of the formula
HOOC-(CH2)n-COOH
where n is zero or an integer, including e.g. oxalic acid, malonic acid, succinic
acid, glutaric acid, adipic acid, pimelic acid and suberic acid. Also included are
acids of the formula
where x is zero or an integer, y is zero or an integer and x and y may be equal or
different and R13 is defined as in (i). Examples of such acids include the alkyl or alkenyl succinic
acids, 2-methylbutanedioic acid, 2-ethylpentanedioic acid, 2-n-dodecylbutanedioic
acid, 2-n-dodecenylbutanedioic acid, 2-phenylbutanedioic acid, and 2-(p-methylphenyl)butanedioic
acid. Also included are polysubstituted alkyl dicarboxylic acids wherein other R13 groups as described above may be substituted on the alkyl chain. These other groups
may be substituted on the same carbon atom or different atoms. Such examples include
2,2-dimethylbutanedioic acid; 2,3-dimethylbutanedioic acid; 2,3,4-trimethylpentanedioic
acid; 2,2,3-trimethylpentanedioic acid; and 2-ethyl-3-methylbutanedioic acid.
[0021] The dicarboxylic acids also include acids of the formula:
HOOC-(C
rH
2r-2)COOH
where r is an integer of 2 or more. Examples include maleic acid, fumaric acid, pent-2-enedioic
acid, hex-2-enedioic acid; hex-3-enedioic acid, 5-methylhex-2-enedioic acid; 2,3-di-methylpent-2-enedioic
acid; 2-methylbut-2-enedioic acid; 2-dodecylbut-2-enedioic acid; and 2-polyisobutylbut-2-enedioic
acid.
[0022] The dicarboxylic acids also include aromatic dicarboxylic acids e.g. phthalic acid,
isophthalic acid, terephthalic acid and substituted phthalic acids of the formula:
where R
13 is defined as in (i) and n = 1, 2, 3 or 4 and when n > 1 then the R
13 groups may be the same or different. Examples of such acids include 3-methylbenzene-1,2-dicarboxylic
acid; 4-phenylbenzene-1,3-dicarboxylic acid; 2-(1-propenyl)benzene-1,4-dicarboxylic
acid, and 3,4-dimethylbenzene-1,2-dicarboxylic acid.
[0023] The carboxylic acid anhydrides include the anhydrides that may be derived from the
carboxylic acids described above. Also included are the anhydrides that may be derived
from a mixture of any of the carboxylic acids described above. Specific examples include
acetic anhydride, propionic anhydride, benzoic anhydride, maleic anhydride, succinic
anhydride, dodecylsuccinic anhydride, dodecenylsuccinic anhydride, an optionally substituted
polyisobutylenesuccinic anhydride, advantageously one having a molecular weight of
between 500 and 2000 daltons, phthalic anhydride and 4-methylphthalic anhydride.
[0024] The phenols from which the anion of the quaternary ammonium compound may be derived
are of many different types. Examples of suitable phenols include:
(i) Phenols of the formula:
[0025]
where n = 1, 2, 3, 4 or 5, where R
13 is defined above and when n > 1 then the substituents may be the same or different.
The hydrocarbon group(s) may be bonded to the benzene ring by a keto or thio-keto
group. Alternatively the hydrocarbon group(s) may be bonded through an oxygen, sulphur
or nitrogen atom. Examples of such phenols include o-cresol; m-cresol; p-cresol; 2,3-dimethylphenol;
2,4-dimethylphenol; 2,3,4-trimethylphenol; 3-ethyl-2,4-dimethylphenol; 2,3,4,5-tetramethylphenol;
4-ethyl-2,3,5,6-tetramethylphenol; 2-ethylphenol; 3-ethylphenol; 4-ethylphenol; 2-n-propylphenol;
2-isopropylphenol; 4-n-butylphenol; 4-isobutylphenol; 4-sec-butylphenol; 4-t-butylphenol;
4-nonylphenol; 2-dodecylphenol; 4-dodecylphenol; 4-octadecylphenol; 2-cyclohexylphenol;
4-cyclohexylphenol; 2-allylphenol; 4-allylphenol; 2-hydroxydiphenyl; 4-hydroxydiphenol;
4-methyl-4'-hydroxydiphenyl; o-methoxyphenol; p-methoxyphenol; p-phenoxyphenol; 2-hydroxydiphenylsulphide;
4-hydroxydiphenylsulphide; 4-hydroxyphenylmethylsulphide; and 4-hydroxyphenyldimethylamine.
Also included are alkyl phenols where the alkyl group is obtained by polymerization
of a low molecular weight olefin e.g. polypropylphenol or polyisobutylphenol.
[0026] Also included are phenols of the formula:
and/or
where R′ and R˝ which may be the same or different are as defined above for R
13 and m and n are integers. Examples of such phenols include 2,2′-dihydroxy-5,5′-dimethyldiphenylmethane;
5,5′-dihydroxy-2,2′-dimethyldiphenylmethane; 4,4′-dihydroxy-2,2′-dimethyl-dimethyldiphenylmethane
; 2,2′-dihydroxy-5,5′-dinonyldiphenylmethane; 2,2′-dihydroxy-5,5′-didodecylphenylmethane
and 2,2′,4,4′-tetra-t-butyl-3,3′-dihydroxydiphenylmethane.
[0027] Also included are sulphurized phenols of the formula:
and/or
where R′ and R˝ which may be the same or different are as defined above, and m and
n are integers and x is 1,2,3 or 4. Examples of such phenols include:
2,2′-dihydroxy-5,5′dimethyldiphenylsulphide;
5,5′-dihydroxy-2,2′-di-t-butyldiphenyldisulphide;
4,4'-dihydroxy-3,3'-di-t-butyldiphenylsulphide;
2,2'-dihydroxy-5,5'-dinonyldiphenyldisulphide;
2,2'-dihydroxy-5,5'didodecyldiphenyldisulphide;
2,2'-dihydroxy-5,5'-didodecyldiphenyltrisulphide; and
2,2'-dihydroxy-5,5'-didodecyldiphenyltetrasulphide.
[0028] The sulphonic acids from which the anion of the quaternary ammonium salt can be derived
include alkyl and aryl sulphonic acids which have a total of 1-200 carbon atoms per
molecule although the preferred range is 1-80 atoms per molecule. Included in this
description are aryl sulphonic acids of the formula:
where n = 1, 2, 3, 4, 5 and when n > 1 the substituents may be the same or different,
and R‴ may represent R
13 as defined above.
[0029] The hydrocarbon group(s) may be bonded to the benzene ring through a carbonyl group
or the thio-keto group. Alternatively the hydrocarbon group(s) may be bonded to the
benzene ring through a sulphur, oxygen or nitrogen atom. Thus examples of sulphonic
acids that may be used include: benzene sulphonic acid; o-toluenesulphonic acid, m-toluenesulphonic
acid; p-toluenesulphonic acid; 2,3-dimethylbenzenesulphonic acid; 2,4-dimethylbenzenesulphonic
acid; 2,3,4-trimethylbenzenesulphonic acid; 4-ethyl-2,3-dimethylbenzenesulphonic acid;
4-ethylbenzenesulphonic acid; 4-n-propylbenzenesulphonic acid; 4-n-butylbenzenesulphonic
acid; 4-isobutylbenzenesulphonic acid; 4-sec-butylbenzenesulphonic acid; 4-t-butylbenzenesulphonic
acid; 4-nonylbenzenesulphonic acid; 2-dodecylbenzenesulphonic acid; 4-dodecylbenzenesulphonic
acid; 4-cyclohexylbenzenesulphonic acid; 2-cyclohexylbenzenesulphonic acid; 2-allylbenzenesulphonic
acid; 2-phenylbenzenesulphonic acid; 4(4'methylphenyl)benzenesulphonic acid; 4-methylmercaptobenzenesulphonic
acid; 2-methoxybenzene sulphonic acid; 4-phenoxybenzenesulphonic acid; 4-methylaminobenzenesulphonic
acid; 2-dimethylaminobenzenesulphonic acid; and 2-phenylaminobenzenesulphonic acid.
Also included are sulphonic acids of the type listed above where R‴ is derived from
the polymerization of a low molecular weight olefin e.g. polypropylenebenzenesulphonic
acid and polyisobutylenebenzenesulphonic acid.
[0030] Also included are sulphonic acids of the formula:
R-SO
3H
where R is alkyl, cycloalkyl, alkenyl or cycloalkenyl. Examples of such sulphonic
acids that may be used include methylsulphonic acid; ethylsulphonic acid; n-propylsulphonic
acid; n-butylsulphonic acid; isobutylsulphonic acid; sec-butylsulphonic acid; t-butylsulphonic;
nonylsulphonic acid; dodecylsulphonic acid; polypropylsulphonic acid; polyisobutylsulphonic
acid; cyclohexylsulphonic acid; and 4-methylcyclohexylsulphonic acid.
[0031] Some of the quaternary ammonium salts which may be employed according to the present
invention are commercially available. It is preferred to use one of these compounds.
Alternatively the quaternary ammonium compounds may be synthesized in any suitable
manner. The quaternary ammonium compounds may be prepared by known processes. Two
methods are preferred for the synthesis of compounds such as quaternary ammonium sulphonates,
sulphurized phenates and carboxylates.
[0032] In the first method a quaternary ammonium hydroxide is prepared by reacting, for
example, a quaternary ammonium chloride with a strong base (for example sodium hydroxide)
in an alcohol (for example methanol).
[0033] After removing the metal halide by filtration, the solution of quaternary ammonium
hydroxide is mixed with the acid in a suitable solvent and allowed to react:
[0034] The rate of reaction may be increased by raising the reaction temperature above ambient.
Once the reaction is complete the solvents and water are removed by distillation.
[0035] In the second method the organic acid is reacted with a metal oxide or hydroxide
to form the metal salt:
[0036] If the reaction is done in a suitable solvent (for example, heptane or toluene) the
water formed during the reaction may be removed by refluxing the solvent and using
a Dean and Stark trap. Once all the water has been removed the solution of the metal
salt is treated with a quaternary ammonium halide:
[0037] The metal halide is removed by filtration, the solvent is removed by distillation.
Alternatively, the solvent can be removed by distillation and the metal halide filtered
from the final product.
[0038] Preferably the fuel composition comprises 5 to 1000 ppm, more preferably 10 to 500
ppm, and most preferably 20 to 200 ppm of quaternary ammonium compound based on parts
of the fuel.
[0039] The cracked component in the fuel oil which leads to the undesirable colour formation
and sediment is generally obtained by cracking of heavy oil and may be fuel oil in
which the main constituent is a fraction otained from a residual oil.
[0040] Typical methods available for the thermal cracking are visbreaking and delayed coking.
Alternatively the fuels may be obtained by catalytic cracking, the principal methods
being moving-bed cracking and fluidized-bed cracking. After cracking, the distillate
oil is extracted by normal or vacuum distillation, the boiling point of the distillate
oil obtained usually being 60-500°C. Compositions composed entirely of this fuel or
fuels which are mixtures of the cracked fraction and normal distillates may be used
in the present invention.
[0041] The present invention accordingly provides a fuel composition comprising a distillate
fraction and a cracked fraction and a quaternary ammonium compound soluble in the
composition, the quaternary ammonium compound having a cation in which the substituent
on the or each quaternary nitrogen is a hydrocarbyl group optionally bearing a tertiary
amino nitrogen atom, and in which cation the ratio of carbon atoms to quaternary nitrogen
atoms is at most 10:1, the anion being derived from a carboxylic acid or anhydride,
a phenol, a sulphurized phenol or a sulphonic acid. The invention also provides the
use of such a quaternary ammonium compound in inhibiting sediment and color formation
in a fuel oil composition, especially one containing a component obtained by the cracking
of heavy oil.
[0042] The proportion by weight of direct-distillation fraction and cracked fraction in
a fuel oil composition which is a mixture can vary considerably, but is usually 1:0.03
- 1:2 and preferably 1:0.05 - 1:1. Typically the content of cracked fraction is usually
5-97%, and preferably 10-50%, based on the weight of the composition.
[0043] The fuel oil compositions of the present invention may contain other additives such
as antioxidants, anticorrosion agents, fluidity improvers, agents absorbing ultraviolet
radiation, detergents, dispersants and cetane improvers in small amounts (for example,
usually less than 2% based on the weight of the composition).
[0044] The present invention is illustrated by the following examples:
Example 1
Synthesis of Tetramethylammonium Dodecylphenate
[0045] A solution of sodium hydroxide (10 g; 0.25 moles) in methanol (100 mls) was added
slowly, under nitrogen, to a stirred solution of tetramethylammonium bromide (38.5
g; 0.25 moles) in methanol (200 mls). When the addition was complete the solution
was stirred for a further 30 minutes.
[0046] The sodium bromide was filtered off and the solution of the tetramethylammonium hydroxide
added directly to a solution of dodecylphenol (65.5 g; 0.25 moles) in toluene (200
mls). The reaction mixture was heated to reflux for 1 hour and then the solvents were
removed by heating to 150°C under vacuum.
[0047] Stanco 150 (83.8 g), a mineral oil base stock (Exxon), was added to the product which
was then filtered through Dicalite 4200 (diatomaceous earth).
TABLE 1 Shows the effect of blending different amounts of a straight distillate with an unhydrofined
catalytically cracked gas oil on sediment and colour in the AMS 77.061 accelerated
stability test.
TABLE 2 Shows typical nitrogen and sulphur levels for straight run distillates and unhydrofined
catalytically cracked gas oils.
TABLE 3 Shows the effect of doping a stable fuel with compounds containing nitrogen and sulphur.
TABLE 4 Shows AMS 77.061 test results on fuels treated with quaternary ammonium compounds
in accordance with the present invention. From a comparison of the results for the
treated fuels with the results for the untreated fuel, it is clear that the compounds
of this invention give good control of colour and sediment.
TABLE 2
The Nitrogen and Sulphur Contents of Various Fuels |
Type of Fuel |
Nitrogen (ppm) |
Sulphur (%) |
Unhydrofined CCGO |
695 |
1.11 |
Unhydrofined CCGO |
650 |
1.70 |
Straight distillate |
50 |
0.24 |
Straight distillate |
70 |
0.25 |
Straight distillate |
97 |
0.23 |
Straight distillate |
128 |
0.24 |
TABLE 3
The Effect of Doping with Dimethyl Pyrrole (DMP) and a Sulphonic Acid (SA) on the
Stability of a Straight Distillate Fuel in the AMS 77.061 Test |
DMP (ppm) (a) |
SA (ppm) (b) |
Sediment (mg/100 ml) |
Colour |
|
|
|
Before |
After |
NIL |
NIL |
0.06, 0.10 |
< 0.5 |
< 1.0 |
|
NIL |
50 |
0.02, 0.00 |
< 0.5 |
< 1.5 |
|
|
|
< 0.5 |
< 1.5 |
|
50 |
NIL |
0.76, 0.59 |
< 0.5 |
< 1.0 |
|
|
|
< 0.5 |
< 1.0 |
|
50 |
50 |
1.06, 1.01 |
< 1.5 |
< 3.0 |
|
|
|
< 1.5 |
< 3.0 |
(a) 2,5-dimethylpyrrole |
(b) a commercially available alkyl-aryl sulphonic acid having a SAN of approximately
80 mg KOH/g of acid |
1. A fuel composition comprising a diesel fuel or a heating oil obtained by the cracking
of heavy oil and a quaternary ammonium compound which is soluble in the fuel and which
comprises a hydrocarbyl cation in which the hydrocarbyl group or groups optionally
carries or carry a tertiary amino nitrogen atom or atoms but is or are otherwise unsubstituted,
and in which cation the ratio of carbon atoms to quaternary nitrogen atoms is not
more than 10:1, and an anion which is derived from an acid which is a carboxylic acid,
carboxylic acid anhydride, phenol, sulphurized phenol or sulphonic acid, other than
an anion derived from a dihydroxy-, hydroxycarboxy-, or dicarboxy-naphthalene.
2. A composition according to claim 1, in which the cation of the quaternary ammonium
compound contains from 1 to 4 quaternary nitrogen atoms.
3. A fuel composition according to claim 1, in which the cation is of the formula:
[R1R2R3R4N]+
in which R1, R2, R3, and R4, which may be the same or different, are each alkyl, cycloalkyl, alkenyl, cycloalkenyl,
aryl, aralkyl or alkaryl such that the number of carbon atoms in the cation does not
exceed 10.
4. A composition according to claim 3, in which the cation is tetramethylammonium.
5. A composition according to claim 1, in which the cation is of the formula:
in which R
5 and R
6 which may be the same or different are each alkyl, cycloalkyl, alkenyl, or cycloalkenyl
such that the number of carbon atoms in the cation does not exceed 10.
6. A composition according to claim 1, in which the cation is of the formula:
in which R
7 is alkyl, cycloalkyl, alkenyl or cycloalkenyl; R
8 is nothing in which case n is 1 or alkyl, cycloalkyl, alkenyl, or cycloalkenyl in
which case n is 2, such that the ratio of carbon atoms to quaternary nitrogen atoms
in the cation does not exceed 10.
7. A composition according to claim 1, in which the cation is of the formula:
[R9R10R11R12N4(CH2)6]m(+)
in which R9 is alkyl, cycloalkyl, alkenyl or cycloalkenyl; R10, R11 or R12 which may be the same or different are each nothing, alkyl, cycloalkyl, alkenyl or
cycloalkenyl, such that the ratio of carbon atoms to quaternary nitrogen atoms in
the cation does not exceed 10; and m is an integer of 1 to 4, the value of m increasing
from unity by one for each of R10, R11, and R12 that represents a substituent.
8. A composition according to claim 7, in which the cation is N-methylhexamethylenetetrammonium
or N,N′N˝,N‴-tetramethylhexamethylenetetrammonium.
9. A composition according to any one of the preceding claims in which the anion of the
quaternary ammonium compound is derived from a carboxylic acid.
10. A composition according to claim 9, in which the carboxylic acid is of the formula:
R
13-COOH
or
in which p and q which may be the same or different are each zero or an integer or
HOOC - (C
rH
2r-2) - COOH
in which r is an integer of 2 or more or
HOOC - (CH
2)
z - COOH
in which z is zero or an integer of 1 or more or
in which R
13 is hydrogen, alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, alkaryl or aralkyl.
11. A composition according to any one of claims 1 to 8, in which the anion of the quaternary
ammonium compound is derived from a carboxylic acid anhydride, advantageously a carboxylic
acid as defined in claim 10 or is a substituted succinic anhydride of the formula:
in which R
13 is defined as in claim 10, or is a substituted anhydride with an optionally substituted
polyisobutylene, in which the polyisobutylene advantageously has a molecular weight
of between 500 to 2000 daltons.
12. A composition according to any one of claims 1 to 8, in which the anion of the quaternary
ammonium compound is derived from a phenol, advantageously one of the formula:
in which s is an integer from 0 to 5 and R
13 is defined as in claim 10, and when s is greater than 1 each R
13 may be the same or different, preferably nonylphenol or dodecylphenol; or of the
formula:
in which t and u, which may be the same or different, are each an integer from 0
to 4; or of the formula:
in which v and w, which may be the same or different, are each an integer from 0
to 4; R
13 is as defined in claim 10, and for each t, u, v and w greater than 1, each R
13 may be the same or different; and x is zero or an integer from 1 to 10.
13. A composition according to claim 12 in which:
- R13 is C9
- v is 1 or 2
- w is 1 or 2
- x is 1 to 6 or in which
- R13 is C12
- both v and w are 1
- x is 1 to 6.
14. A composition according to any one of claims 1 to 8, in which the anion of the quaternary
ammonium compound is derived from a sulphonic acid, preferably one of the formula:
or R
13SO
3H in which y is an integer from 0 to 5; R
13 is as defined in claim 10, and when y is greater than 1 each R
13 may be the same or different.
15. A composition as defined in any one of the preceding claims in which the fuel oil
comprises a direct-distillation fraction and a cracked fraction, the cracked fraction
comprising 5 to 97% by weight of the composition.
16. A composition as defined in any one of the preceding claims which comprises from 5
to 1000 ppm, advantageously 10 to 500 ppm, and preferably 20 to 200 ppm, of the quaternary
ammonium compound.
17. Use of a quaternary ammonium compound as defined in any one of claims 1 to 14 for
inhibition of sediment and colour formation in a diesel fuel or heating oil.
1. Brennstoffzusammensetzung, die einen Dieselkraftstoff oder ein Heizöl, die durch Cracken
von Schweröl erhalten worden sind, und eine quartäre Ammoniumverbindung umfaßt, die
in dem Kraftstoff bzw. Brennstoff löslich ist und ein Kohlenwasserstoffkation, in
dem die Kohlenwasserstoffgruppe oder die Kohlenwasserstoffgruppen gegebenenfalls ein
tertiäres Aminostickstoffatom oder tertiäre Aminostickstoffatome trägt bzw. tragen,
aber ansonsten unsubstituiert ist bzw. sind, wobei das Verhältnis von Kohlenstoffatomen
zu quartären Stickstoffatomen in dem Kation nicht mehr als 10:1 beträgt, und ein Anion
umfaßt, das von einer Säure abgeleitet ist, die eine Carbonsäure, ein Carbonsäureanhydrid,
Phenol, sulfuriertes Phenol oder eine Sulfonsäure ist, aber von einem Anion verschieden
ist, das von einem Dihydroxy-, Hydroxy-, Carboxy- oder Dicarboxynaphthalin abgeleitet
ist.
2. Zusammensetzung nach Anspruch 1, in der das Kation der quartären Ammoniumverbindung
1 bis 4 quartäre Stickstoffatome enthält.
3. Brennstoffzusammensetzung nach Anspruch 1, in der das Kation die Formel
[R1R2R3R4N]+
hat, in der R1, R2, R3 und R4, die gleich oder verschieden sein können, jeweils Alkyl, Cycloalkyl, Alkenyl, Cycloalkenyl,
Aryl, Aralkyl oder Alkaryl sind, so daß die Anzahl der Kohlenstoffatome in dem Kation
10 nicht übersteigt.
4. Zusammensetzung nach Anspruch 3, in der das Kation Tetramethylammonium ist.
5. Zusammensetzung nach Anspruch 1, in der das Kation die Formel
hat, in der R
5 und R
6, die gleich oder verschieden sein können und jeweils Alkyl, Cycloalkyl, Alkenyl oder
Cycloalkenyl sind, so daß die Anzahl der Kohlenstoffatome in dem Kation 10 nicht übersteigt.
6. Zusammensetzung nach Anspruch 1, in der das Kation die Formel
hat, in der R
7 Alkyl, Cycloalkyl, Alkenyl oder Cycloalkenyl ist, R
8 nichts ist, wobei in diesem Fall n gleich 1 ist, oder Alkyl, Cycloalkyl, Alkenyl
oder Cycloalkenyl ist, wobei in diesem Fall n gleich 2 ist, so daß das Verhältnis
von Kohlenstoffatomen zu quartären Stickstoffatomen in dem Kation 10 nicht übersteigt.
7. Zusammensetzung nach Anspruch 1, in der das Kation die Formel
[R9R10R11R12N4(CH2)6]m(+)
hat, in der R9 Alkyl, Cycloalkyl, Alkenyl oder Cycloalkenyl ist, R10, R11 oder R12, die gleich oder verschieden sein können, jeweils nichts, Alkyl, Cycloalkyl, Alkenyl
oder Cycloalkenyl sind, so daß das Verhältnis von Kohlenstoffatomen zu quartären Stickstoffatomen
in dem Kation 10 nicht übersteigt, und m eine ganze Zahl von 1 bis 4 ist, wobei der
Wert von m von eins ausgehend für jedes von R10, R11 und R12, das einen Substituenten wiedergibt, um eins erhöht wird.
8. Zusammensetzung nach Anspruch 7, in der das Kation N-Methylhexamethylentetrammonium
oder N,N',N",N‴-Tetramethylhexamethylentetrammonium ist.
9. Zusammensetzung nach einem der vorhergehenden Ansprüche, in der das Anion der quartären
Ammoniumverbindung von einer Carbonsäure abgeleitet ist.
10. Zusammensetzung nach Anspruch 9, in der die Carbonsäure die Formel
R
13-COOH
oder
in der p und q, die gleich oder verschieden sein können, jeweils Null oder eine ganze
Zahl sind, oder
HOOC - (C
rH
2r-2) - COOH ,
in der r eine ganze Zahl von 2 oder mehr ist, oder
HOOC - (CH
2)
z - COOH
,
in der z Null oder eine ganze Zahl von 1 oder mehr ist, oder
hat, in denen R
13 Wasserstoff, Alkyl, Cycloalkyl, Alkenyl, Cycloalkenyl, Aryl, Alkaryl oder Aralkyl
ist.
11. Zusammensetzung nach einem der Ansprüche 1 bis 8, in der das Anion der quartären Ammoniumverbindung
von einem Carbonsäureanhydrid, vorteilhafterweise von einer Carbonsäure gemäß Anspruch
10 abgeleitet ist oder ein substituiertes Bernsteinsäureanhydrid mit der Formel
in der R
13 wie in Anspruch 10 definiert ist, oder ein mit einem gegebenenfalls substituierten
Polyisobutylen substituiertes Anhydrid ist, in dem das Polyisobutylen vorteilhafterweise
ein Molekulargewicht zwischen 500 und 2 000 Dalton hat.
12. Zusammensetzung nach einem der Ansprüche 1 bis 8, bei der das Anion der quartären
Ammoniumverbindung von einem Phenol, vorteilhafterweise einem Phenol mit der Formel
in der s eine ganze Zahl von 0 bis 5 ist und R
13 wie in Anspruch 10 definiert ist, und jeder R
13 gleich oder verschieden sein kann, wenn s größer als 1 ist, vorzugsweise Nonylphenol
oder Dodecylphenol, oder von der Formel
in der t und u, die gleich oder verschieden sein können und jeweils eine ganze Zahl
von 0 bis 4 sind, oder von der Formel
in der v und w, die gleich oder verschieden sein können und jeweils eine ganze Zahl
von 0 bis 4 sind, R
13 wie in Anspruch 10 definiert ist und jedes R
13 für jedes t, u, v und w größer als 1 gleich oder verschieden sein kann, und x Null
oder eine ganze Zahl von 1 bis 10 ist, abgeleitet ist.
13. Zusammensetzung nach Anspruch 12, in der
- R13 C9 ist,
- v 1 oder 2 ist,
- w 1 oder 2 ist,
- x 1 bis 6 ist, oder in der
- R13 C12 ist,
- v und w beide gleich 1 sind und
- x 1 bis 6 ist.
14. Zusammensetzung nach einem der Ansprüche 1 bis 8, in der das Anion der quartären Ammoniumverbindung
von einer Sulfonsäure, vorzugsweise einer Sulfonsäure mit der Formel
oder R
13SO
3H
abgeleitet ist, in der y eine ganze Zahl von 0 bis 5 ist, R
13 wie in Anspruch 10 definiert ist, und jedes R
13 gleich oder verschieden sein kann, wenn y größer als 1 ist.
15. Zusammensetzung nach einem der vorhergehenden Ansprüche, in der das Brennstofföl eine
Direktdestillationsfraktion und eine gecrackte Fraktion umfaßt, wobei die gecrackte
Fraktion 5 bis 97 Gew.% der Zusammensetzung ausmacht.
16. Zusammensetzung gemäß einem der vorhergehenden Ansprüche, die 5 bis 1000 ppm, vorteilhafterweise
10 bis 500 ppm und vorzugsweise 20 bis 2000 ppm der quartären Ammoniumverbindung umfaßt.
17. Verwendung einer quartären Ammoniumverbindung gemäß einem der Ansprüche 1 bis 14 zur
Hemmung der Sediment- und Farbbildung in Dieselkraftstoff oder Heizöl.
1. Composition de combustible comprenant un combustible diesel ou une huile de chauffe,
obtenu par craquage d'un pétrole lourd, et un composé d'ammonium quaternaire qui est
soluble dans le combustible et qui comprend un cation hydrocarbyle, dans lequel le
ou les groupes hydrocarbyle portent facultativement un ou plusieurs atomes d'azote
de groupe amino tertiaire mais sont par ailleurs non substitués, et cation dans lequel
le rapport des atomes de carbone aux atomes d'azote quaternaires est non supérieur
à 10:1, et un anion qui est dérivé d'un acide qui est un acide carboxylique, un anhydride
d'acide carboxylique, un phénol, un phénol sulfuré ou un acide sulfonique, autre qu'un
anion dérivé d'un dihydroxy-, hydroxycarboxy- ou dicarboxy-naphtalène.
2. Composition suivant la revendication 1, dans laquelle le cation du composé d'ammonium
quaternaire contient 1 à 4 atomes d'azote quaternaires.
3. Composition de combustible suivant la revendication 1, dans laquelle le cation répond
à la formule :
[R1R2R3R4N]+
dans laquelle R1, R2, R3 et R4, qui peuvent être identiques ou différents, représentent chaucn un groupe alkyle,
cycloalkyle, alcényle, cycloalcényle, aryle, aralkyle ou alkaryle de telle sorte que
le nombre d'atomes de carbone dans le cation n'excède pas 10.
4. Composition suivant la revendication 3, dans laquelle le cation est un cation tétraméthylammonium.
5. Composition suivant la revendication 1, dans laquelle le cation répond à la formule
:
dans laquelle R
5 et R
6, qui peuvent être identiques ou différents, représentent chacun un groupe alkyle,
cycloalkyle, alcényle ou cycloalcényle de telle sorte que le nombre d'atomes de carbone
dans le cation n'excède pas 10.
6. Composition suivant la revendication 1, dans laquelle le cation répond à la formule
:
dans laquelle R
7 représente un groupe alkyle, cycloalkyle, alcényle ou cycloalcényle ; R
8 est absent, auquel cas
n est égal à 1 ou représente un groupe alkyle, cycloalkyle, alcényle ou cycloalcényle,
auquel cas n est égal à 2, de telle sorte que le rapport des atomes de carbone aux
atomes d'azote quaternaires dans le cation n'excède pas 10.
7. Composition suivant la revendication 1, dans laquelle le cation répond à la formule
:
[R9R10R11R12N4 (CH2)6]m(+)
dans laquelle R9 représente un groupe alkyle, cycloalkyle, alcényle ou cycloalcényle ; R10, R11 ou R12, qui peuvent être identiques ou différents, ne représentent chacun rien ou bien représentent
chacun un groupe alkyle, cycloalkyle, alcényle ou cycloalcényle, de telle sorte que
le rapport des atomes de carbone aux atomes d'azote quaternaires dans le cation n'excède
pas 10 ; et m est un nombre entier de 1 à 4, la valeur de m augmentant d'une unité à la fois pour chacun des groupes R10, R11 et R12 représentant un substituant.
8. Composition suivant la revendication 7, dans laquelle le cation est un cation N-méthylhexaméthylènetétrammonium
ou N,N',N',N‴-tétraméthylhexaméthylènetétrammonium.
9. Composition suivant l'une quelconque des revendications précédentes, dans laquelle
l'anion du composé d'ammonium quaternaire est dérivé d'un acide carboxylique.
10. Composition suivant la revendication 9, dans laquelle l'acide carboxylique répond
à la formule :
R
13-COOH
ou
dans laquelle
p et
q, qui peuvent être identiques ou différents, sont chacun égaux à zéro ou à un nombre
entier, ou à la formule
HOOC - (C
rH
2r-2) - COOH
dans laquelle
r est un nombre entier égal ou supérieur à 2, ou à la formule
HOOC - (CH
2)
z - COOH
dans laquelle
z est égal à zéro ou à un nombre entier égal ou supérieur à 1, ou à la formule
dans laquelle R
13 représente l'hydrogène, un groupe alkyle, cycloalkyle, alcényle, cycloalcényle, aryle,
alkaryle ou aralkyle.
11. Composition suivant l'une quelconque des revendications 1 à 8, dans laquelle l'anion
du composé d'ammonium quaternaire est dérivé d'un anhydride d'acide carboxylique,
avantageusement un acide carboxylique répondant à la définition suivant la revendication
10, ou bien consiste en un anhydride succinique substitué, de formule :
dans laquelle R
13 répond à la définition suivant la revendication 10, ou bien représente un anhydride
substitué avec un polyisobutylène facultativement substitué, dans lequel le polyisobutylène
a avantageusement un poids moléculaire compris dans l'intervalle de 500 à 2000 daltons.
12. Composition suivant l'une quelconque des revendications 1 à 8, dans laquelle l'anion
du composé d'ammonium quaternaire est dérivé d'un phénol, avantageusement d'un phénol
répondant à la formule :
dans laquelle
s est un nombre entier de 0 à 5 et R
13 répond à la définition suivant la revendication 10 et, lorsque
s est supérieur à 1, les groupes R
13 peuvent être identiques ou différents et représentent chacun de préférence un groupe
nonylphénol ou dodécylphénol ; ou bien à la formule :
dans laquelle
t et
u, qui peuvent être identiques ou différents, représentent chacun un nombre entier
de 0 à 4 ; ou bien à la formule :
dans laquelle
v et
w, qui peuvent être identiques ou différents, représentent chacun un nombre entier
de 0 à 4 ; R
13 répond à la définition suivant la revendication 10 et, pour chacun des indices
t,
u,
v et
w supérieur à 1, les groupes R
13 peuvent être identiques ou différents ; et
x est égal à zéro ou à un nombre entier de 1 à 10.
13. Composition suivant la revendication 12, dans laquelle :
- R13 est un groupe en C9
- v est égal à 1 ou 2
- w est égal à 1 ou 2
- x a une valeur de 1 à 6, ou dans laquelle
- R13 représente un groupe en C12
- v et w sont l'un et l'autre égaux à 1
- x a une valeur de 1 à 6.
14. Composition suivant l'une quelconque des revendications 1 à 8, dans laquelle l'anion
du composé d'ammonium quaternaire est dérivé d'un acide sulfonique, de préférence
d'un acide sulfonique de formule :
ou R
13SO
3H
dans laquelle
y est un nombre entier de 0 à 5 ; R
13 répond à la définition suivant la revendication 10 et, lorsque
y est supérieur à 1, les groupes R
13 peuvent être identiques ou différents.
15. Composition répondant à la définition suivant l'une quelconque des revendications
précédentes, dans laquelle l'huile combustible comprend une fraction de distillation
directe et une fraction de craquage, la fraction de craquage représentant 5 à 97 %
en poids de la composition.
16. Composition répondant à la définition suivant l'une quelconque des revendications
précédentes, qui comprend 5 à 1000 ppm, avantageusement 10 à 500 ppm et de préférence
20 à 200 ppm du composé d'ammonium quaternaire.
17. Utilisation d'un composé d'ammonium quaternaire répondant à la définition suivant
l'une quelconque des revendications 1 à 14 pour inhiber la formation d'un sédiment
et l'apparition d'une couleur dans un combustible diesel ou une huile de chauffe.