Note: Descriptions are shown in the official language in which they were submitted.
Case EL-6250
_ 1 _ 2~~1~51
HYDROCARBONACEOUS FUEL COMPOSITIONS AND
ADDITIVES THEREFOR
This invention relates to liquid fuel compositions of enhanced properties,
particularly as regards combustion and stability characteristics.
Heretofore certain organometallic compounds have been found effective as
combustion improvers for distillate fuels such as home heating oils and the
like. For
example U.S. Pat. No. 3,112,789 describes the use of cyclopentadienyl
manganese
tricarbonyls for this purpose, and the compound methylcyclopentadienyl
manganese
tricarbonyl (MMT) has been sold in the form of a solution in a hydrocarbon
diluent
as a combustion improver for distillate fuels of this type.
Bis(cyclopentadienyl) iron
has also been promoted and sold as a combustion improver for use in such
fuels.
Keszthelyi et al report in Period. Polytech.. Chem. Eng., Volume 21(1), pages
79-93 (1977) that in the combustion of light fuel oils in evaporating burners,
0.025%
cyclopentadienyl manganese tricarbonyl was effective for soot reduction. And
in
Margantsev~re Antidetonatorv, edited by A. N. Nesmeyanov, Nauka, Moscow, 1971,
at pages 192-199, Makhov et al report test work indicating that addition of
cyclopentadienyl manganese tricarbonyl to diesel fuel reduces the level of
smokiness
of the exhaust gases.
Zubarev et al in Rxbn. Khoz.~Moscow), Volume 9, pages 52-4 (1977), report
test results on the addition to a fuel mixture of diesel fuel and marine
residual fuel
of cyclopentadienyl manganese tricarbonyl (CMT) alone or in a blend containing
"a
scavenger and a solvent". It is indicated that the CMT alone reduced carbon
deposits
on the intake valves but not on other engine surfaces, and that it reduced
smoke.
The CMT blend ("Ts8") is reported to have reduced carbon deposition more
effectively, especially on the intake valves, cylinder head and piston head.
Canadian Patent No. 1,188,891 describes an additive for fuel oils and diesel
fuels and other liquid combustibles and motor fuels designed to improve
combustion,
reduce soot formation and enhance storage stability. Such additive is composed
of
at least one oil-soluble or oil-dispersible organic compound of a transition
metal or
an alkaline earth metal; and at least one oxidation and polymerisation
inhibitor for
Case EL-6250
_2_ 2~~1~5i
hydrocarbons stable at temperatures of at least 300 ° C. According to
the patentee,
the presence in such fuels of compounds of transition metals such as copper,
manganese, cobalt, nickel and iron accelerate fuel deterioration in
accelerated
stability tests conducted at 149 ° C in the presence of air. Such
compounds as MMT,
S Ferrocene, copper naphthenate, iron naphthenate, and manganese naphthenate
are
indicated to cause such deterioration in the absence of a high temperature
(e.g.,
300 ° C) stabiliser such as heat-stable alkyl phenols, amines,
aminophenols,
dithiophosphates, dithiocarbamates and imidazoles and inorganic inhibitors in
the
form of oxides or hydroxides of aluminum, magnesium or silicon. EP 0078249 B1
is
1.0 to the same general effect, and indicates that the additive may be a
combination of
a transition metal compound and an alkaline earth metal compound, as well as
either
such compound separately.
G.B. Patent No. 1,413,323 describes a mufti-component diesel fuel additive to
avoid or reduce the formation of deposits on injector parts. The additive
comprises,
15 inter alia, an ester of oleic or naphthenic acid having an acid number
below 200; a
naphthenic acid ester of cresol; an alkoxyalkyl ester of an aliphatic
carboxylic acid;
an organometallic tricarbonyl cyclopentadiene compound such as
cyclopentadienyl
manganese tricarbonyl; an amide derivative of a polyolefin obtained by the
reaction
of a polyolefin substituted succinic acid or anhydride with a polyamine; a
copolymer
20 of ethylene and a vinyl (or hydrocarbyl-substituted vinyl) ester of a
carboxylic acid
wherein the copolymer has a number average molecular weight of more than 3000;
a re-odoriser composed of a mixture of natural and synthetic alcohols, ketones
and
ethers; kerosene; and a petroleum distillate.
U.S. Pat. No. 4,505,718 describes compositions comprising the combination of
25 a transition metal salt such as a manganese carboxylate, and an ashless
hydrocarbon
soluble ashless dispersant. An optimum balance between beneficial and
deleterious
effects is said to be achieved in oils of lubricating viscosity and
hydrocarbon fuels.
Additive compositions based on or including one or more fuel-soluble
manganese carbonyl compounds and one or more fuel-soluble alkali and/or
alkaline
30 earth metal-containing detergents have been found in these laboratories to
provide
excellent improvements in the combustion characteristics of various
hydrocarbon-
Case EL-6250
_3 _ 2~5~~~1
aceous fuels. Unfortunately, in many cases such additive combinations can
cause fuel
destabilisation -- i.e., the additives can cause the hydrocarbonaceous fuel
with which
they are blended to be less stable on exposure to air or oxygen at elevated
temperatures than the fuel would be absent such additives.
Thus a need has arisen for an effective way of preventing such fuel
destabilisation without interfering with the combustion-enhancing
effectiveness of
such additive combinations and without materially increasing the cost of the
additive
combinations. This invention is deemed to fulfill this need in a most
efficacious
manner.
In accordance with this invention destabilisation of liquid hydrocarbonaceous
fuels containing a combination of at least one fuel-soluble manganese carbonyl
compound and at least one fuel-soluble alkali or alkaline earth metal-
containing
detergent is inhibited by inclusion in the fuel of at least one fuel-soluble
metal
deactivator of the chelation type, i.e., a metal deactivator capable of
complexing
dissolved metals or metal ions.
Thus in one of its embodiments this invention provides an additive
composition for hydrocarbonaceous fuels. Such additive composition comprises:
a) one or more fuel-soluble manganese carbonyl compounds;
b) one or more fuel-soluble alkali or alkaline earth metal-containing
detergents -- e.g., one or more neutral or basic alkali or alkaline earth
metal salts of at least one sulphonic acid, and/or at least one carboxylic
acid, and/or at least one salicyclic acid, and/or at least one alkylphenol,
and/or at least one sulphurised alkylphenol, and/or at least one organic
phosphorus acid having at least one carbon-to-phosphorus linkage; and
c) one or more fuel-soluble metal-deactivators of the chelation type.
The additive compositions are thus composed of three different types of
essential or
indispensable ingredients, namely, components a), b), and c).
In another of its embodiments, this invention provides a fuel composition
which comprises a major amount of a liquid hydrocarbonaceous fuel containing a
minor combustion-improving amount of components a), b) and c) as just
described.
Pursuant to preferred embodiments of this invention, the additive
Case EL-6250
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compositions and fuel compositions are essentially halogen-free, that is, they
contain
no more than 10 ppm of halogen, if any.
Preferred manganese carbonyl compounds -- component a) above -- are
cyclopentadienyl manganese tricarbonyl compounds. The preferred component b)
salts are the sodium, potassium, calcium and magnesium salts of sulphonic
acids, of
alkylphenols, of sulphurised alkylphenols, and of carboxylic acids, especially
aromatic
carboxylic acids. Preferred metal deactivators for use as component c) are
fuel-soluble Schiff bases having one or more chelation centers of the formula
~~-- CH=N-
OH
'The aromatic ring in the above formula can be further substituted or it can
be
unsubstituted, and if substituted can contain from 1 to 4 substituents (other
than
hydrogen atoms), which can be organic or inorganic of any types provided such
substituent or plurality of substituents does not interfere with the ability
of the metal
deactivator to complex with dissolved metals or metal ions and does not
otherwise
render the metal deactivator unsuitable for use as, for example, by rendering
it
unstable, pyrophoric, highly toxic, explosive or fuel-insoluble. In other
words, any
such substituent(s) on the ring should be innocuous.
A feature of this invention is the discovery that the metal deactivator can
effectively inhibit fuel destabilisation even when present in the fuel in less
than
equimolar quantity with respect to either the manganese carbonyl compounds) or
the metal detergents) present therein. Another feature of this invention is
the
discovery that the metal deactivator can effectively inhibit fuel
destabilisation while
in the presence of still other additive components, such as ashless
dispersants, amine
stabilisers, and demulsifying agents.
Compositions for use in heating gas oils and similar burner fuels preferably
contain, in addition to components a), b) and c) above, one or more of the
following:
d) at least one ashless dispersant;
e) at least one fuel-soluble demulsifying agent; and
f) at least one aliphatic or cycloaliphatic amine. Compositions for use in
Case EL-6250
20~14~1
road diesel fuels and similar middle distillate fuels preferably contain,
in addition to components a), b) and c) above, component d), namely,
at least one ashless dispersant and/or component e), namely, at least
one fuel-soluble demulsifying agent.
The above and other embodiments and features of this invention will become
apparent from the ensuing description and appended claims.
As used herein the term "fuel-soluble" means that the compound or com-
ponent under discussion has sufficient solubility at ordinary ambient
temperature in
the hydrocarbonaceous fuel in which it is to be used to provide a homogeneous
solution containing the compound or component in at least the lowest
concentration
of the concentration ranges specified herein for such compound or component.
ivlanganese carbon 1v com op ands. The manganese compounds -- component
a) -- of the compositions of this invention are characterised by being fuel
soluble and
by having at least one carbonyl group bonded to a manganese atom.
The most desirable general type of manganese carbonyl compounds utilised
in accordance with this invention comprise organomanganese polycarbonyl com-
pounds. For best results, use should be made of a cyclopentadienyl manganese
tricarbonyl compound of the type described in U. S. Pat. Nos. 2,818,417 and
3,127,351. Thus use can be made of such compounds as cyclopentadienyl
manganese
tricarbonyl, methylcyclopentadienyl manganese tricarbonyl,
ethylcyclopentadienyl
manganese tricarbonyl, dimethylcyclopentadienyl manganese tricarbonyl,
trimethyl-
cyclopentadienyl manganese tricarbonyl, propylcyclopentadienyl manganese
tricar-
bonyl, isopropylcyclopentadienyl manganese tricarbonyl, butylcyclopentadienyl
manganese tricarbonyl, pentylcyclopentadienyl manganese tricarbonyl,
hexylcyclo-
pentadienyl manganese tricarbonyl, ethylmethylcyclopentadienyl manganese
tricar-
bonyl, dimethyloctylcyclopentadienyl manganese tricarbonyl,
dodecylcyclopentadienyl
manganese tricarbonyl, indenyl manganese tricarbonyl, and like compounds in
which
the cyclopentadienyl moiety contains up to about 18 carbon atoms.
A preferred organomanganese compound is cyclopentadienyl manganese
tricarbonyl. Particularly preferred for use in the practise of this invention
is
methylcyclopentadienyl manganese tricarbonyl.
Case EL-6250
_6_ 2~~~.~~~.
Methods for the synthesis of cyclopentadienyl manganese tricarbonyls are well
documented in the literature. See for example, in addition to U. S. Pat. Nos.
2,818,417 and 3,127,351 noted above, U. S. Pat. Nos. 2,868,816; 2,898,354;
2,960,514;
and 2,987,529, among others.
Other less preferable organomanganese compounds which may be employed
include the non-ionic diamine manganese tricarbonyl halide compounds such as
bromo manganese dianiline tricarbonyl and bromo manganese dipyridine
tricarbonyl,
described in U. S. Pat. No. 2,902,489; the acyl manganese tricarbonyls such as
methylacetyl cyclopentadienyl manganese tricarbonyl and benzoyl methyl cyclo-
pentadienyl manganese tricarbonyl, described in U. S. Pat. No. 2,959,604; the
aryl
manganese pentacarbonyls such as phenyl manganese pentacarbonyl, described in
U.
S. Pat. No. 3,007,953; and the aromatic cyanomanganese dicarbonyls such as
mesitylene cyanomanganese dicarbonyl, described in U. S. Pat. No. 3,042,693.
Likewise, use can be made of cyclopentadienyl manganese dicarbonyl compounds
of
the formula RMn(CO)ZL, where R is a substituted or unsubstituted
cyclopentadienyl
group having 5 to 18 carbon atoms, and L is a ligand, such as an olefin, an
amine,
a phosphine, SOZ, tetrahydrofuran, or the like. Such compounds are referred
to, for
example in, Herberhold, M., Metal ~r-Complexes, Vol. II, Amsterdam, Elsevier,
1967
or Giordano, P. J. and Weighton, M.S., Inorg. Chem., 1977, 16, 160. Manganese
pentacarbonyl dimer (dimanganese decarbonyl) can also be employed if desired.
~yletal-containingdetergents. The metal-containing detergents are exemplified
by oil-soluble neutral and basic salts of alkali or alkaline earth metals with
one or
more of the following acidic substances (or mixtures thereof): (1) sulphonic
acids,
(2) carboxylic acids, (3) salicylic acids, (4) alkylphenols, (S) sulphurised
alkylphenols,
(6) organic phosphorus acids characterised by at least one direct carbon-to-
phosphorus linkage. Such organic phosphorus acids include those prepared by
the
treatment of an olefin polymer (e.g., polyisobutene having a molecular weight
of
1000) with a phosphorising agent such as phosphorus trichloride, phosphorus
hepta-
sulfide, phosphorus pentasulphide, phosphorus trichloride and sulphur, white
phosphorus and a sulphur halide, or phosphorothioic chloride. The most
commonly
used salts of such acids are those of sodium, potassium, lithium, calcium,
magnesium,
Case EL-6250
-
strontium and barium.
The term "basic salt" is used to designate metal salts wherein the metal is
present in stoichiometrically larger amounts than the organic acid radical.
The
commonly employed methods for preparing the basic salts involve heating a
mineral
oil solution of an acid with a stoichiometric excess of a metal neutralising
agent such
as the metal oxide, hydroxide, carbonate, bicarbonate, or sulphide at a
temperature
of about 50 ° C, and filtering the resulting mass. The use of a
"promoter" in the
neutralisation step to aid the incorporation of a large excess of metal
likewise is
known. Examples of compounds useful as the promoter include phenolic
substances
such as phenol, naphthol, alkylphenol, thiophenol, sulphurised alkylphenol,
and
condensation products of formaldehyde with a phenolic substance; alcohols such
as
methanol, 2-propanol, octyl alcohol, cellosolve, carbitol, ethylene glycol,
stearyl
alcohol, and cyclohexyl alcohol; and amines such as aniline, phenylenediamine,
phenothiazine, phenyl-betanaphthylamine, and dodecylamine. Aparticularly
effective
method for preparing the basic salts comprises mixing an acid with an excess
of a
basic alkaline earth metal neutralising agent and at least one alcohol
promoter, and
carbonating the mixture at an elevated temperature such as 60 ° -200
° C.
Examples of suitable metal-containing detergents include, but are not limited
to, such substances as lithium phenates, sodium phenates, potassium phenates,
calcium phenates, magnesium phenates, sulphurised lithium phenates,
sulphurised
sodium phenates, sulphurised potassium phenates, sulphurised calcium phenates,
and
sulphurised magnesium phenates wherein each aromatic group has one or more
aliphatic groups to impart hydrocarbon solubility; the basic salts of any of
the
foregoing phenols or sulphurised phenols (often referred to as "overbased"
phenates
or "overbased sulphurised phenates"); lithium sulphonates, sodium sulphonates,
potassium sulphonates, calcium sulphonates, and magnesium sulphonates wherein
each sulphonic acid moiety is attached to an aromatic nucleus which in turn
usually
contains one or more aliphatic substituents to impart hydrocarbon solubility;
the
basic salts of any of the foregoing sulphonates (,often referred to as
"overbased
sulphonates' ; lithium salicylates, sodium salicylates, potassium salicylates,
calcium
salicylates, and magnesium salicylates wherein the aromatic moiety is usually
Case EL-6250
_g_
20~1~51
substituted by one or more aliphatic substituents to impart hydrocarbon
solubility;
the basic salts of any of the foregoing salicylates (often referred to as
"overbased
salicylates"); the lithium, sodium, potassium, calcium and magnesium salts of
hydrolysed phosphosulphurised olefins having 10 to 2000 carbon atoms or of
hydrolysed phosphosulphurised alcohols and/or aliphatic-substituted phenolic
compounds having 10 to 2000 carbon atoms; lithium, sodium, potassium, calcium
and
magnesium salts of aliphatic carboxylic acids and aliphatic-substituted
cycloaliphatic
carboxylic acids; the basic salts of the foregoing carboxylic acids (often
referred to
as "overbased carboxylates" and many other similar alkali and alkaline earth
metal
salts of oil-soluble organic acids. Mixtures of salts of two or more different
alkali
and/or alkaline earth metals can be used. Likewise, salts of mixtures of two
or more
different acids or two or more different types of acids (e.g., one or more
calcium phe-
nates with one or more calcium sulphonates) can also be used. While rubidium,
cesium and strontium salts are feasible, their expense renders them
impractical for
most uses. Likewise, while barium salts are effective, the status of barium as
a heavy
metal under a toxicological cloud renders barium salts less preferred for
present-day
usage.
Metal deactivators. As noted above, component c) -- the third indispensable
component of the compositions of this invention -- is a metal deactivator of
the
chelator type, i.e., one or more substances which have the capability of
reacting or
complexing with dissolved metal and/or metal ions. Examples of the chelator
type
of metal deactivators include 8-hydroxyquinoline, ethylene diamine
tetracarboxylic
acid, p-diketones such as acetylacetone, p-ketoesters such as octyl
acetoacetate, and
the like. The preferred metal deactivators generally regarded as chelators,
are Schiff
bases,suchasN,N'-disalicylidene-1,2-ethanediamine,N,N'-disalicylidene-1,2-
propane-
diamine, N,N'-disalicylidene-1,3-propanediamine, N,N'-disalicylidene-1,2-cyclo-
hexanediamine, N,N"-disalicylidene-N'-methyl-dipropylenetriamine, 3'-ethoxy-
5,2',6'-
trimethyl-N,N'-disalicylidene-biphenyl-2,4'-diyldiamine, S'-ethoxy-3,5,2'-
trimethyl-
N,N'-disalicylidene-biphenyl-2,4'-diyldiamine, and analogous compounds inwhich
one
or more of the salicylidene groups are substituted by innocuous groups such as
alkyl,
alkoxy, alkylthio, alkenyl, cycloalkyl, cycloalkenyl, aryl, alkoxyalkyl,
aralkyl, carboxyl,
Case EL-6250
_9_ 2~~1~~1
esterified carboxyl, etc. Thus a wide variety of known metal deactivators are
available for use as component c) in the practise of this invention. The most
preferred metal deactivators of this type are N,N'-disalicylidene-1,2-
alkanediamines
and N,N'-disalicylidene-1,2-cycloalkanediamines, especially N,N'-
disalicylidene-1,2-
propanediamine. Mixtures of metal deactivators can be used.
We now turn our attention to optional, but preferred, additional components
d), e) and f) which may be utilised in the compositions of this invention. As
noted
above, these additional components do not materially interfere with the
enhanced
fuel stability realised by combining component c) with components a) and b).
There-
after, other aspects of the invention are considered.
Ashless dispersants. Ashless dispersants, which make up component d), are
described in numerous patent specifications, mainly as additives for use in
lubricant
compositions, but their use in hydrocarbon fuels has also been described.
Ashless
dispersants leave little or no metal-containing residue on combustion. They
generally
contain only carbon, hydrogen, oxygen and in most cases nitrogen, but
sometimes
contain in addition other non-metallic elements such as phosphorus, sulphur or
boron.
The preferred ashless dispersant is an alkenyl succinimide of an amine having
at least one primary amino group capable of forming an imide group.
Representative
examples are given in U.S. Pat. Nos. 3,172,892; 3,202,678; 3,216,936;
3,219,666;
3,254,025; 3,272,746; and 4,234,435. The alkenyl succinimides may be formed by
con-
ventional methods such as by heating an alkenyl succinic anhydride, acid, acid-
ester,
acid halide, or lower alkyl ester with an amine containing at least one
primary amino
group. The alkenyl succinic anhydride may be made readily by heating a mixture
of
olefin and malefic anhydride to about 180 ° -220 ° C. The olefin
is preferably a
polymer or copolymer of a lower monoolefin such as ethylene, propylene,
isobutene
and the like. The more preferred source of alkenyl group is from polyisobutene
having a molecular weight up to 10,000 or higher. In a still more preferred
embodiment the alkenyl group is a polyisobutene group having a molecular
weight
of about 500-5,000, preferably about 900-2,000, and especially about 900-
1,200.
Amines which may be employed in forming the ashless dispersant include any
Case EL-6250
-1~- 2~51~~1
that have at least one primary amino group which can react to form an imide
group.
A few representative examples are: methylamine, 2-ethylhexylamine, n-dodecyl
amine, stearylamine, N,N-dimethyl-propanediamine, N-(3-aminopropyl)morpholine,
N-dodecyl-propanediamine, N-aminopropyl-piperazine, ethanolamine, N-ethanol
S ethylenediamine and the like.
The preferred amines are the alkylene polyamines such as propylene diamine,
dipropylene triamine, di-(1,2-butylene)triamine, and tetra-(1,2-
propylene)pentamine.
The most preferred amines are the ethylene polyamines which can be depicted
by the formula
HZN(CHZCH2NH)"H
wherein n is an integer from one to about ten. These include: ethylene
diamine,
diethylene triamine, triethylene tetramine, tetraethylene pentamine,
pentaethylene
hexamine, and the like, including mixtures thereof in which case n is the
average
value of the mixture. These ethylene polyamines have a primary amine group at
each end so can form mono-alkenylsuccinimides and bis-alkenylsuccinimides.
Commercially available ethylene polyamine mixtures usually contain minor
amounts
of branched species and cyclic species such as N-aminoethyl piperazine, N,N'-
bis-
(aminoethyl)piperazine, N,N'-bis(piperazinyl)ethane, and like compounds. The
preferred commercial mixtures have approximate overall compositions falling in
the
range corresponding to diethylene triamine to tetraethylene pentamine,
mixtures
generally corresponding in overall makeup to tetraethylene pentamine being
most
preferred.
Thus especially preferred ashless dispersants for use in the present invention
are the products of reaction of a polyethylene polyamine, e.g. triethylene
tetramine
or tetraethylene pentamine with a hydrocarbon substituted carboxylic acid or
anhydride made by reaction of a polyolefin, preferably polyisobutene, having a
number average molecular weight of 500 to 5,000, preferably 900 to 2,000 and
especially 900 to 1,200, with an unsaturated polycarboxylic acid or anhydride,
e.g.,
malefic anhydride, malefic acid, fumaric acid, or the like, including mixtures
of two or
more such substances.
Another class of useful ashless dispersants includes alkenyl succinic acid
esters
Case EL-6250
-11-
and diesters of alcohols containing 1-20 carbon atoms and 1-6 hydroxyl groups.
Representative examples are described in U.S. Pat. Nos. 3,331,776; 3,381,022;
and
3,522,179. The alkenyl succinic portion of these esters corresponds to the
alkenyl
succinic portion of the succinimides described above including the same
preferred
and most preferred subgenus, e.g., polyisobutenyl succinic acids wherein the
polyisobutenyl group has a number average molecular weight of 500 to 5,000,
preferably 900-2,000, especially 900 to 1,200.
Alcohols useful in preparing the esters include methanol, ethanol, isobutanol,
octadecanol, eicosanol, ethylene glycol, diethylene glycol, tetraethylene
glycol,
diethylene glycol monoethylether, propylene glycol, tripropylene glycol,
glyceroh
sorbitol, 1;1,1-trimethylol ethane, 1,1,1-trimethylol propane, 1,1,1-
trimethylol butane,
pentaerythritol, dipentaerythritol, and the like. -
The succinic esters are readily made by merely heating a mixture of alkenyl
succinic acid, anhydrides or lower alkyl (e.g., CI-C4) ester with the alcohol
while
distilling out water or lower alkanol. In the case of acid-esters less alcohol
is used.
In act, acid-esters made from alkenyl succinic anhydrides do not evolve water.
In
another method the alkenyl succinic acid or anhydrides can be merely reacted
with
an appropriate alkylene oxide such as ethylene oxide, propylene oxide, and the
like,
including mixtures thereof.
In another embodiment the ashless dispersant is an alkenyl succinic ester-
amide mixture. These may be made by heating the above-described alkenyl
succinic
acids, anhydrides or lower alkyl esters with an alcohol and an amine either
sequentially or in a mixture. The alcohols and amines described above are also
useful in this embodiment. Alternatively, amino alcohols can be used alone or
with
the alcohol and/or amine to form the ester-amide mixtures. The amino alcohol
can
contain 1-20 carbon atoms, 1-6 hydroxy groups and 1-4 amine nitrogen atoms.
Examples are ethanolamine, diethanolamine, N-ethanol-diethylene triamine, and
trimethylol aminomethane.
Representative examples of suitable ester-amide mixtures are described in
U.S. Pat. Nos. 3,184,474; 3,576,743; 3,632,511; 3,804,763; 3,836,471;
3,862,981;
3,936,480; 3,948,800; 3,950,341; 3,957,854; 3,957,855; 3,991,098; 4,071,548;
and
Case EL-6250
12 20~1~~1
4,173,540.
Such ashless dispersants containing alkenyl succinic residues may, and as is
well known, be post-reacted with boron compounds, phosphorus derivatives
and/or
carboxylic acid acylating agents, e.g. malefic anhydride.
Another useful class of ashless dispersants includes the Mannich condensates
of hydrocarbyl-substituted phenols, formaldehyde or formaldehyde precursors
(e.g.
paraformaldehyde) and an amine having at least one primary amine group and con-
taining 1-10 amine groups and 1-20 carbon atoms. Mannich condensates useful in
this invention are described in U.S. Pat. Nos. 3,442,808; 3,448,047;
3,539,633;
3,591,598; 3,600,372; 3,634,515; 3,697,574; 3,703,536; 3,704,308; 3,725,480;
3,726,882;
3,736,357; 3,751,365; 3,756,953; 3,793,202; 3,798,165; 3,798,247; 3,803,039;
and
3,413,347.
More preferred Mannich condensates are those made by condensing a polyiso-
butenyl phenol wherein the polyisobutyl group has an average molecular weight
of
about 800-3,000 with formaldehyde or a formaldehyde precursor and an ethylene
polyamine having the formula:
HZN(CH2CH2NH)"H
wherein n is an integer from one to ten or mixtures thereof especially those
in which
n has an average value of 3-S.
Typical post-treated ashless dispersants such as succinimides and Mannich
condensates are described in U.S. Pat. Nos. 3,036,003; 3,087,936; 3,200,107;
3,216,936;
3,254,025; 3,256,185; 3,278,550; 3,280,234; 3,281,428; 3,282,955; 3,312,619;
3,366,569;
3,367,943; 3,373,111; 3,403,102; 3,442,808; 3,455,831; 3,455,832; 3,493,520;
3,502,677;
3,513,093; 3,533,945; 3,539,633; 3,573,010; 3,579,450; 3,591,598; 3,600,372;
3,639,242;
3,649,229; 3,649,659; 3,658,846; 3,697,574; 3,702,575; 3,703,536; 3,704,308;
3,708,422;
and 4,857,214.
A further type of ashless dispersants which can be used comprises inter-
polymers of oil-solubilising monomers such as decyl methacrylate, vinyl decyl
ether
and high molecular weight olefins with monomers containing polar substituents,
e.g.,
aminoalkyl acrylates or acrylamides and poly(oxyethylene)-substituted
acrylates.
These may be characterised as "polymeric dispersants" and examples thereof are
Case EL-6250
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20~14~1
disclosed in the following U.S. Pat. Nos.: 3,329,658; 3,449,250; 3,519,565;
565;
3,666,730; 3,687,849; and 3,702,300.
Another class of ashless dispersants which can advantageously be used in the
fuel compositions of this invention are the imidazoline dispersants which can
be
represented by the formula:
H2C - N - R2
H2C C - R1
N
wherein R1 represents a hydrocarbon group having 1 to 30 carbon atoms, e.g. an
alkyl
or alkenyl group having 7 to 22 carbon atoms, and R2 represents a hydrogen
atoms
or a hydrocarbon radical of 1 to 22 carbon atoms, or an aminoalkyl,
acylaminoalkyl
or hydroxyalkyl radical having 2 to 50 carbon atoms. Such long-chain alkyl (or
long-chain alkenyl) imidazoline compounds may be made by reaction of a
corresponding long-chain fatty acid (of formula Rl-COOH), for example oleic
acid,
with'an appropriate polyamine. The imidazoline formed is then ordinarily
called, for
example, oleylimidazoline where the radical Rl represents the oleyl residue of
oleic
acid. Other suitable alkyl substituents in the 2- position of these
imidazolines include
undecyl, heptadecyl, lauryl and erucyl. Suitable N-substituents of the
imidazolines
(i.e. radicals RZ) include hydrocarbyl groups, hydroxyalkyl groups, aminoalkyl
groups,
and acylaminoalkyl groups. Examples of these various groups include methyl,
butyl,
decyl, cyclohexyl, phenyl, benzyl, tolyl, hydroxyethyl, aminoethyl,
oleylaminoethyl and
stearylaminoethyl.
Other suitable ashless dispersants which may be incorporated in the fuel
compositions of this invention include the products of condensation of a
cyclic
anhydride with a straight-chain N-alkylpolyamine of the formula:
R-(NH-R'-)"NH2
where n is an integer at least equal to 1, usually 3 to 5, R is a saturated or
unsaturated linear hydrocarbon radical of 10 to 22 carbon atoms and R' is a
divalent
alkylene or alkylidene radical of .1 to 6 carbon atoms. Examples of such
polyamines
include N-oleyl-1,3-propanediamine, N-stearyl-1,3-propanediamine, N-oleyl-1,3
Case EL-6250 CA 02051451 1998-0~-29
-14-
butanediamine, N-oleyl-2-methyl-1,3-propanediamine, N-oleyl-1,3-
pentanediamine,
N-oleyl-2-ethyl-1,3-propanediamine,N-stearyl-1,3-butanediamine,N-stearyl-2-
methyl-
1,3-propanediamine, N-stearyl-1,3-pentanediamine, N-stearyl-2-ethyl-1,3-
propanedi-
amine, N-oleyl-dipropylenetriamine and N-stearyldipropylenetriamine. Such
linear
N-alkylpolyamines are condensed with, e.g., a succinic, malefic, phthalic or
hexa-
hydrophthalic acid anhydride which may be substituted by one or more radicals
of
up to 5 carbon atoms each.
Another class of ashless dispersant which can be incorporated in the
compositions of the present invention are the products of reaction of an
ethoxylated
amine made by reaction of ammonia with ethylene oxide with a carboxylic acid
of 8
to 30 carbon atoms. The ethoxylated amine may be, for example, mono-, di- or
tri-
ethanolamine or a polyethoxylated derivative thereof, and the carboxylic acid
may be,
for example, a straight or branched chain fatty acid of 10 to 22 carbon atoms,
a
naphthenic acid, a resinic acid or an alkyl aryl carboxylic acid.
Still another type of ashless dispersants which can be used in the practise of
this invention are the a-olefin-maleimide copolymers such as are described in
U.S.
Pat. No. 3,909,215. Such copolymers are alternating copolymers of N-
substituted
maleimides and aliphatic a-olefins of from 8 to 30 carbon atoms. The
copolymers
may have an average of 4 to 20 maleimide groups per molecule. The substituents
on the nitrogen of the maleimide may be the same or different and are organic
radicals composed essentially of carbon, hydrogen and nitrogen having a total
of 3
to 60 carbon atoms. A commercially available material which is highly suitable
for
use in this invention is Chevron OFA 425B, and this material is believed to be
or
comprise an a-olefin maleimide copolymer of the type described in U.S. Pat.
No.
3,909,215. Whatever its composition, it works quite well.
All the aforesaid types of ashless dispersants are described in the literature
and many are available commercially. Mixtures of various types of ashless
dispersants can, of course, be used.
Because of environmental concerns it is desirable to employ ashless
dispersants which contain little, if any, halogen atoms such as chlorine
atoms. Thus,
in order to satisfy such concerns, it is desirable (although not necessary
from a
*Trade-mark
Case EL-6250
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20~I~~1
performance standpoint) to select ashless dispersants (as well as the other
components used in the compositions of this invention) such that the total
halogen
content of the overall fuel composition does not exceed 10 ppm. Indeed, the
lower
the better. Most desirably, the additive composition contains no detectable
amount
of halogen.
Typical halogen (chlorine)-free ashless dispersants suitable for use in the
compositions of this invention include, in addition to various types described
herein-
above, those described in the following recently-published applications: WO
9003359
and EP 355288.
Demulsifying agents. Any of a variety of demulsifying agents can be used in
the fuel end fuel additive compositions of this invention. The demulsifying
agent
improves the water tolerance level of the fuel compositions by minimizing or
preventing excessive emulsion formation.
Exemplary demulsifiers which may be employed include poly(alkylphenol)
formaldehyde condensates and the polyalkylenoxy modified reaction products
thereof.
These compounds are prepared by reacting an alkylphenol with formaldehyde and
thereafter reacting the reaction product of the above with a CZ to C6 alkylene
oxide
such as ethylene oxide and propylene oxide. The demulsifiers have a
generalized
structural formula
O(UO)yH
R5
x
wherein U is an alkylene of 2 to 6 carbons; y is an integer averaging between
4 and
10; x is an integer averaging between 4 and 10; and RS is an alkyl having from
4 to
15 carbon atoms.
Preferred demulsifiers described by the above formula are polyethyleneoxy
modified methylene bridged poly(alkylphenol) polymers having a polyethyleneoxy
Case EL-6250
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chain of 8 to 20 carbons and preferably from 10 to 16 carbons and at least
about 75
number percent of the polyethyleneoxy chains being within the range specified.
The
methylene bridged poly(alkylphenol) portion of the polymer has from 4 to 10
and
preferably from 5 to 8 repeating methylene bridged alkylphenol units with 4 to
15
and preferably 6 to 12 carbons in the alkyl group. In preferred embodiments,
the
alkyl groups are a mixture of alkyls having between 4 and 12 carbon atoms.
Illustrative alkylphenols include p-isobutylphenol, p-diisobutylphenol,
p-hexylphenol, p-heptylphenol, p-octylphenol, p-tripropylenephenol, and
p-dipropylenephenol, etc.
Another type of demulsifier component is an ammonia-neutralised
sulphonated alkylphenol. These compounds have the general structure:
S03NH4
Rl
HO
wherein R1 is a hydrocarbyl group having from 4 to 15 carbon atoms, preferably
from
6 to 12.
These compounds are prepared by sulphonating an alkylated phenol and
thereafter neutralising the sulphonated product with ammonia.
Another type of demulsifier is an oxyalkylated glycol. These compounds are
prepared by reacting a polyhydroxy alcohol such as ethylene glycol,
trimethylene gly-
col, etc., with ethylene or propylene oxide. Many of the compounds are
commercially
available from BASF-Wyandotte Chemical Company under the PLURONIC trade-
mark. They are polyethers terminated by hydroxy groups and produced by the
block
copolymerisation of ethylene oxide and propylene oxide. The ethylene oxide
blocks
act as the hydrophiles and the propylene oxide blocks as the hydrophobes. They
are
available in a wide range of molecular weights and with varying ratios of
ethylene
oxide to propylene oxide.
One type of commercially available demulsifiers comprises a mixture of
alkylaryl sulphonates, polyoxyalkylene glycols and oxyalkylated alkylphenolic
resins.
Case EL-6250 CA 02051451 1998-07-29
-17-
Such products are supplied by Petrolite Corporation under the TOLAD trademark.
One such propriety product, identified as TOLAD 286K, is understood to be a
mixture of these components dissolved in a solvent composed of alkyl benzenes.
This
product has been found efficacious for use in the compositions of this
invention. A
$ related product, TOLAD 286, is also suitable. In this case the product
apparently
contains the same kind of active ingredients dissolved in a solvent composed
of heavy
aromatic naphtha and isopropanol. However, other known demulsifiers can be
used.
Aliphatic or cXcloaliphatic amine. When it is desired to include one or more
amines in the compositions of this invention, any of a wide variety of
suitable amines
can be used. This component contributes stability to the systems in which it
is
employed. Typically a monoamine is employed although polyamines can be used,
if
desired. Among the vast array of suitable amines are included the amines
referred
to in U.S. Pat. No. 3,909,215 such as tertiary alkyl primary amines including
Primene
81R and the like, and amines referred to in EP 188,042, namely
alkyldimethylamines
in which the alkyl group has 8 to 14 carbon atoms or mixtures thereof. Also
suitable
are mixed alkyl-cycloalkyl amines such as N-cyclohexyl-N-butyl amine, N-methyl-
cyclohexyl-N-octyl amine, etc., as well as di- and tricycloalkyl amines such
as
N,N-dicyclohexyl amine, N,N-di-(ethylcyclohexyl)amine, N,N,N-tricyclohexyl
amine,
and the like. Preferred amines include N-cycloalkyl-N,N-dialkyl amines and
N-cycloalkenyl-N,N-dialkylamines such as N-cyclohexyl-N,N-diethyl amine, N-
cyclo-
hexyl-N,N-dibutyl amine, N-cycloheptyl-N,N-dimethyl amine, N-cyclooctyl-N,N-
dilauryl amine, N-cyclohexenyl-N,N-dipropyl amine, and like compounds.
Particularly
preferred is N-cyclohexyl-N,N-dimethyl amine. Mixtures of various amines, such
as
those referred to above, are also suitable for use in accordance with this
invention.
HXdrocarbonaceous fuels. In principle, the advantages of this invention
may be achieved in any liquid hydrocarbonaceous fuel derived from petroleum,
coal,
shale and/or tar sands. In most instances, at least under present
circumstances, the
base fuels will be derived primarily, if not exclusively, from petroleum.
The invention is thus applicable to such fuels as kerosene, jet fuel, aviation
fuel, diesel fuel, home heating oil, light cycle oil, heavy cycle oil, light
gas oil, heavy
gas oil, bunker fuels, residual fuel oils, ultra heavy fuel oils, and in
general, any liquid
*Trade-mark
Case EL-6250
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2~~1~a~
(or flowable) hydrocarbonaceous product suitable for combustion either in an
engine
(e.g., diesel fuel, gas turbine fuels, etc.) or in a burner apparatus (e.g.,
gas oils, inland
heavy fuel oil, residual fuel oils, visbreaker fuel oils, home heating oils,
etc.). Other
suitable fuels may include liquid fuels derived from biomass, such as
vegetable oils
(e.g., rapeseed oil, jojoba oil, cottonseed oil, etc.); or refuse-derived
liquid fuels such
as fuels derived from municipal and/or industrial wastes; or waste oils and/or
liquid
waste biomass and its derivatives; or mixtures of any of the foregoing
substances.
In many cases, specifications exist for various hydrocarbonaceous fuels or
grades thereof, and in any event the nature and character of such fuels are
well-
known and reported in the literature.
The additive compositions comprising components a), b), c) and at least one
of components d), e) and f) -- preferably two of components d), e) and f) and
most
preferably all three of components d), e) and f) -- are especially useful in
heating gas
oils and like burner fuels and fuel oils for agricultural and industrial
engines. Typical
specifications for such fuel oils can be found, for example, in BS 2869 : Part
2 : 1988
of the British Standards Institution. Typical specifications for automotive or
road
diesel fuels, in which compositions composed of components a), b), c), d) and
e) are
especially useful, appear in BS 2869: Part 1: 1988 of the British Standards
Institution.
As can be appreciated, a vast number of such specifications exist from country
to
country.
~~centrations and ~ orn tions. In general, the components of the additive
compositions, especially components a) and b), are employed in the fuels in
minor
amounts sufficient to improve the combustion characteristics and properties of
the
base hydrocarbonaceous fuel in which they are employed. The metal deactivator,
component c), is employed in a minor amount sufficient to inhibit fuel
destabilisation
in fuels containing components a) and b). The amounts will thus vary in
accordance
with such factors as base fuel type and service conditions for which the
finished fuel
is intended. However, generally speaking, the following concentrations (ppm)
of the
components (active ingredients) in the base fuels are illustrative:
CA 02051451 2002-05-07
z
' - 19-
More Particularly
General Preferred Preferred Preferred
Range Range an a Range
Component a) 1.5-10,000 2.5-1,500 3-100 3-25
S Component b) 4-10,000 5-6,000 6-300 6-1~
Component c) 0.1-6,000 0.25-1,000 1-500 1.5-I00
In the case of fuels additionally containing one or more of components d), e),
and f), the following concentrations (ppm) of active ingredients are typical:
Particularly
~' General Preferred Preferred
Range Range Range
Component d) 0-15,000 8-5,000 10-200
Component e) 0-4,000 0.5-200 2-SO
Component f) 0-10,000 5-200 10-50
It will be appreciated that the individual components a), b); and c), and also
d), e), and/or f) (if used), can be separately blended into the fuel or can be
blended
therein in various subcombinations, if desired. Ordinarily, the particular
sequence
of such blending steps is not critical. Moreover, such components can be
blended in
the form of a solution in a diluent. It is preferable, however, to blend the
components used in the form of an additive concentrate of this invention, as
this
simplifies the blending operations, reduces the likelihood of blending errors,
and
takes advantage of the compatibility and solubility characteristics afforded
by the
overall concentrate.
The additive concentrates of this invention will contain components a), b),
and
ZS c), and optionally, but preferably, one or more of components d), e), and
f) in
amounts proportioned to yield fuel blends consistent with the concentrations
tabu
lated above. In most cases, the additive concentrate will contain one or more
diluents such as light mineral oils, to facilitate handling and blending of
the
Case EL-6250
_20_ 2-~~1~~--~
concentrate. Thus concentrates containing up to 90% by weight of one or more
diluents or solvents are frequently used.
Other components. If desired or deemed of help in given situations, one or
more other components can be included in the compositions of this invention.
For
example, the additive compositions and fuel compositions of this invention can
also
contain antioxidant, e.g., one or more phenolic antioxidants, aromatic amine
antioxi-
dants, sulphurised phenolic antioxidants, and organic phosphites, among
others.
Examples include 2,6-di-tert-butylphenol, liquid mixtures of tertiary
butylated phe-
nols, 2,6-di-tert-butyl-4-methylphenol, 4,4'-methylenebis(2,6-di-tert-
butylphenol),
2,2'-methylenebis(4-methyl-6-tert-butylphenol), mixed methylene-bridged
polyalkyl
phenols, ~ 4,4'-thiobis(2-methyl-6-tert-butylphenol), N,N'-di-sec-butyl-p-
phenylene-
diamine, 4-isopropylaminodiphenyl amine, phenyl-a-naphthyl amine, and phenyl-p-
naphthyl amine.
Corrosion inhibitors comprise another type of optional additive for use in
this
invention. Thus use can be made of dimer and trimer acids, such as are
produced
from tall oil fatty acids, oleic acid, linoleic acid, or the like. Products of
this type are
currently available from various commercial sources, such as, for example, the
dimer
and trimer acids sold under the HYSTRENE trademark by the Humco Chemical
Division of Witco Chemical Corporation and under the EMPOL trademark by Emery
Chemicals. Another useful type of corrosion inhibitor for use in the practise
of this
invention are the alkenyl succinic acid and alkenyl succinic anhydride
corrosion
inhibitors such as, for example, tetrapropenylsuccinic acid,
tetrapropenylsuccinic
anhydride, tetradecenylsuccinic acid, tetradecenylsuccinic anhydride,
hexadecenylsuc-
cinic acid, hexadecenylsuccinic anhydride, and the like. Also useful are the
half
esters of alkenyl succinic acids having 8 to 24 carbon atoms in the alkenyl
group with
alcohols such as the polyglycols. Preferred materials are the aminosuccinic
acids or
derivatives thereof represented by the formula:
R6 O
R~- C - C - OR5
R4~ ~ 1
N - C - C - OR
R3 R2 O
Case EL-6250
-21-
2~~~.~~~.
wherein each of Rl, RZ, R5, R6 and R' is, independently,
a hydrogen atom or a hydrocarbyl group containing 1 to 30 carbon atoms, and
wherein each of R3 and R4 is, independently, a hydrogen atom, a hydrocarbyl
group
containing 1 to 30 carbon atoms, or an aryl group containing from 1 to 30
carbon
atoms.
The groups R1, R2, R3, R4, R5, R6 and R', when in the form of a hydrocarbyl
group, can be, for example, alkyl, cycloalkyl or aromatic containing groups.
Pre-
ferably R' and RS are the same or different straight-chain or branched-chain
hydrocarbon radicals containing 1-20 carbon atoms. Most preferably, Ri and RS
are
saturated hydrocarbon radicals containing 3-6 carbon atoms. R2, either R3 or
R4, R6
and R', when in the form of hydrocarbyl groups, are preferably the same or
different
straight-chain or branched-chain saturated hydrocarbon radicals. Preferably a
dialkyl
ester of an aminosuccinic acid is used in which R' and RS are the same or
different
alkyl groups containing 3-6 carbon atoms, RZ is a hydrogen atom, and either R3
or
R4 is an alkyl group containing 15-20 carbon atoms or an aryl group which is
derived
from a saturated or unsaturated carboxylic acid containing 2-10 carbon atoms.
Most preferred is a dialkylester of an aminosuccinic acid of the above formula
wherein Rl and RS are isobutyl, RZ is a hydrogen atom, R3 is octadecyl and/or
octadecenyl and R4 is 3-carboxy-1-oxo-2-propenyl. In such ester R6 and R' are
most
preferably hydrogen atoms.
The heavier fuels of this invention may contain cold flow improvers and
pour-point depressants, e.g., olefin/vinyl acetate copolymers such as
ethylene/vinyl
acetate copolymers and polymethacrylates. Antifoam agents such as silicones;
metal
deactivators of the passivator type, e.g., the thiadiazoles such as HITEC~ 314
additive (Ethyl Petroleum Additives, Ltd.; Ethyl Petroleum Additives, Inc.);
and dyes
can also be used in the compositions of this invention. The diesel fuels may
contain
cetane improvers such as peroxy compounds and organic nitrates (e.g., amyl
nitrates,
hexyl nitrates, heptyl nitrates, octyl nitrates, and other alkyl nitrates
having about 4
to about IO carbon atoms including mixtures thereof). A few specific examples
of
such alkyl nitrates are cyclohexyl nitrate, methoxypropyl nitrate, mixed
nitrate esters
made by nitration of fusel oil, 2-ethylhexyl nitrate, n-octyl nitrate, n-decyl
nitrate, etc.
Case EL-6250
2~1~1~~1
-22-
Typical peroxy compounds include acetyl peroxide, benzoyl peroxide, tert-butyl-
peroxyacetate, and cumene hydroperoxide.
All of the foregoing optional other components are well known in the art and
are used in the usual proportions. In selecting such optional component(s),
care
should be taken to ensure that the selected material or combination of
material is
compatible with components of the overall composition in which it is being
used.
The following non-limiting examples in which all parts and percentages are
by weight illustrate the invention.
EXAMPLE 1
An additive composition is formed by blending together the following
components in the amounts specified:
4.0% Methylcyclopentadienyl manganese tricarbonyl (MMT) as a blend containing
62% MMT and 38% diluent (mainly aromatic solvent);
6.0% Overbased calcium sulphonate as a blend with 44% 100 solvent neutral oil
and having a typical TBN of 295;
1.6% N,N'-disalicylidene-1,2-propanediamine as an 80% solution in xylene; and
88.4% Heavy aromatic naphtha.
This composition is well adapted for use in heating gas oil, for example at
treat rates of 250 to 37,000 ppm, typically 500 ppm.
EXAMPLE 2
An additive composition is formed by blending together the following
components in the amounts specified:
4.0% Methylcyclopentadienyl manganese tricarbonyl (MMTj as a blend containing
62% MMT and 38% diluent (mainly aromatic solventj;
6.0% Overbased calcium sulphonate as a blend with 44% 100 solvent neutral oil
and having a typical TBN of 295;
1.2% N,N'-disalicylidene-1,2-propanediamine as an 80°lo solution in
xylene; and
88.8% Heavy aromatic naphtha.
This composition is well adapted for use in heating gas oil, for example at
treat rates of 250 to 37,000 ppm, typically S00 ppm.
Case EL-6250
23
EXAMPLE 3
An additive composition is formed by blending together the following
components in the amounts specified:
4.0% Methylcyclopentadienyl manganese tricarbonyl (MMT) as a blend containing
62% MMT and 38% diluent (mainly aromatic solvent);
6.0% Overbased calcium sulphonate as a blend with 44% 100 solvent neutral oil
and having a typical TBN of 295;
1.6% N,N'-disalicylidene-1,2-propanediamine as an 80% solution in xylene;
9.2% Chevron OFA 425B, an ashless dispersant believed to comprise a C13~C16
a-olefin-malefic anhydride copolymer aminated with an N-alkylpropylene
diamine as a 50% solution in oil;
9.2% N-cyclohexyl-N,N-dimethylamine; and
70.0% Heavy aromatic naphtha.
This composition is well adapted for use in heating gas oil, for example at
treat rates of 250 to 37,000 ppm, typically 500 ppm.
EXAMPLE 4
An additive composition is formed by blending together the following
components in the amounts specified:
4.0% Methylcyclopentadienyl manganese tricarbonyl (MMT) as a blend containing
62% MMT and 38% diluent (mainly aromatic solvent);
6.0% Overbased calcium sulphonate as a blend with 44% 100 solvent neutral oil
and having a typical 'I'BN of 295;
1.6% N,N'-disalicylidene-1,2-propanediamine as an 80% solution in xylene;
6.9% Chevron OFA 425B, an ashless dispersant believed to comprise a C13~C16
a-olefin-malefic anhydride copolymer aminated with an N-alkylpropylene
diamine as a 50% solution in oil;
5.2% N-cyclohexyl-N,N-dimethylamine; and
76.3% Heavy aromatic naphtha.
This composition is well adapted for use in heating gas oil, for example at
treat rates of 250 to 37,000 ppm, typically S00 ppm.
Case EL-6250 CA 02051451 1998-0~-29
-24-
EXAMPLE S
The procedure of Example 3 is repeated using the following proportions of
the additive components:
4.0% MMT as the blend of Example 3;
S 6.0% Overbased calcium sulphonate as the blend of Example 3;
1.2% N,N'-disalicylidene-1,2-propanediamine as the solution of Example 3;
6.9% Chevron OFA 425B, as the solution of Example 3;
6.9% N-cyclohexyl-N,N-dimethylamine; and
75.0% Heavy aromatic naphtha.
EXAMPLE 6
The procedure of Example 3 is repeated using the following proportions of
the additive components:
4.0% MMT as the blend of Example 3;
6.0% Overbased calcium sulphonate as the blend of Example 3;
1S 1.2% N,N'-disalicylidene-1,2-propanediamine as the solution of Example 3;
6.9% Chevron OFA 42SB, as the solution of Example 3;
S.2% N-cyclohexyl-N,N-dimethylamine; and
76.7% Heavy aromatic naphtha.
EXAMPLE 7
An additive composition of this invention is formed using the following:
4.0% MMT as the 62% solution in diluent specified in Example 1;
6.0% Overbased calcium sulphonate as the blend in 100 solvent neutral oil
specified
in Example 1;
1.6% N,N'-disalicylidene-1,2-propanediamine as an 80% solution in heavy
aromatic
2S naphtha;
S.S% Polyisobutenyl succinimide of tetraethylene pentamine (made from
polybutenes with Mn of approximately 9S0) as a 2S% solution in oil;
1.4% Akzo Armogard DS021 demulsifier, believed to be a blend of demulsifier
bases and surfactants in an aromatic solvent;
S.2% N-cyclohexyl-N,N-dimethylamine; and
76.3% Heavy aromatic naphtha.
*Trade-mark
Case EL-6250
_25_ 2~~1~:~1
This composition is useful, for example at treat rates of 250 to 37,000 ppm,
typically 500 ppm, in heating gas oils.
EXAMPLE 8
Using the procedure of Example 1, the following components are blended
together:
4.5% MMT blend specified in Example 1;
33.0% Overbased calcium sulphonate blend specified in Example 1;
1.8% N,N'-disalicylidene-1,2-butanediamine as a 75% solution in heavy aromatic
naphtha;
22.7% Polyisobutenyl succinimide of tetraethylene pentamine (made from
polybutene of Mn of approximately 950) as a 23% solution in a solvent oil;
6.8% Demulsifier (Tolad 286K); and
31.2% Heavy aromatic naphtha diluent.
When used, for example at a concentration in the range of 200 to 26,500 ppm,
typically 400 ppm, this additive concentrate is especially adapted for
improving
combustion of road diesel fuels.
EXAMPLE 9
An additive concentrate is formed using the following components:
2.8% MMT;
14.5% Overbased calcium sulphonate blend;
1.5% N,N'-disalicylidene-1,2-cyclohexanediamine as a 60% solution in aromatic
naphtha;
17.1% Polyisobutenyl succinimide of an equivalent mixture of diethylene
triamine,
triethylene tetramine, and tetraethylene pentamine (made from polyisobutene
of Mn of approximately 1000); and
64.1% Inert diluents (primarily 100 solvent neutral mineral oil).
EXAMPLE 10
The following additive concentrate is formed:
5.0% C~clopentadienyl manganese tricarbonyl in a blend containing 40% aromatic
hydrocarbon solvent;
30.5% Overbased magnesium sulphonate;
Case EL-6250
-26-
1.8% N,N'-disalicylidene-1,2-propanediamine;
24.5% Mannich condensation product of p-(polyisobutenyl)phenol (made from
polyisobutene of Mn of 750), formaldehyde and triethylene tetramine;
5.6% Akzo Armogard D5021 demulsifier; and
32.6% Heavy aromatic naphtha diluents.
EXAMPLE 11
Examples 9 and 10 are repeated substituting in one case overbased potassium
sulphonate and in another case overbased calcium phenate for the sulphonates
of
Examples 9 and 10.
EXAMPLE 12
The procedures of Examples 4, 7 and 8 are repeated except that in one case
the overbased calcium sulphonate is replaced by an equivalent amount of
overbased
magnesium sulphonate, in another case by an equivalent amount of overbased
sodium sulphonate, and in a third case by an equivalent amount of overbased
potassium sulphonate.
EXAMPLE 13
The respective compositions of Examples 1 through 9 and 12 are formed with
the exception that the methylcyclopentadienyl manganese tricarbonyl is
replaced in
one case by an equivalent amount of cyclopentadienyl manganese tricarbonyl, in
another case by an equivalent amount of cyclopentadienyl manganese dicarboxyl
triphenylphosphine, in a third case by an equivalent amount of indenyl
manganese
tricarbonyl, in a fourth case by an equivalent amount of dimanganese
decacarbonyl,
and in still another case by an equivalent amount of a mixture composed of 90%
methylcyclopentadienyl manganese tricarbonyl and 10% cyclopentadienyl
manganese
tricarbonyl.
EXAMPLE 14
The respective compositions of Examples 4 and 7 are blended at concentra-
tions of 300, 500 and 1,000 ppm in a heating gas oil having a specific gravity
at 15 ° C
(DIN 51757) of 0.845 g/mI~ a kinematic viscosity at 20 ° C {DIN 51562)
of 5.3 mm2
per second, a pour point {DIN ISO 3016) of -9 ° C, a sulphur content
(DIN 51 400)
of 0.19%, and a distillation profile (DIN S 1 751) of 27 volume % boiling to
250 ° C
Case EL-6250
27
and 92 volume % boiling to 350 ° C.
EXAMPLE 15
Example 14 is repeated except that the same amounts of the respective com
ponents of the respective compositions of Examples 4 and 7 are blended
individually
or in sub-combinations into the gas oil.
EXAMPLE 16
The composition of Example 8 is blended at concentrations of 300, 500, 1,000
and 1,500 ppm in a diesel fuel satisfying the requirements of DIN 51 601-DK
(February 1986).
EXAMPLE 17
Example 16 is repeated except that the same amounts of the respective
components of the composition of Example 8 are blended individually or in sub-
combinations into the diesel fuel.
EXAMPLE 18
The procedures of Examples 16 and 17 are repeated using commercially
available diesel fuels suitable for use as railway diesel fuel, tractor diesel
fuel,
off road diesel fuel and inland waterways fuel.
EXAMPLE 19
Examples 14 and 15 are repeated using as the fuels commercially-available
heavy fuel oils and residual oils (e.g., industrial and refinery fuel oils)
such as inland
heavy fuel oils, and also hydrocarbonaceous marine fuels. The additive treat
levels
in these fuels are 500, 800 and 1,500 ppm.
The enhanced stability characteristics of the compositions of this invention
are
illustrated by the results of a series of thermal oxidative stability tests
conducted in
accordance with ASTM Test Procedure D2274. In these tests two different commer-
cially-available base fuels were used. One was a relatively stable diesel fuel
having
a cetane number of 52.? (Fuel A). The other was a relatively unstable diesel
fuel
having a cetane number of 52.5 (Fuel B). Each of these fuels was tested in
duplicate
without the addition thereto of any additives. In addition Fuels A and B
containing
various additive mixtures based on the combination of MMT and calcium
sulphonate
both with and without metal deactivator of the chelation type were subjected
to the
Case EL-6250
-28-
same ASTM test procedure. The compositions tested and the results obtained are
summarised in the following table in which the additive components were as
follows:
"MMT' as the 62% blend as in Example 1;
"Ca Det." is calcium sulphonate as the 44% blend as in Example 1;
"Metal Deact." is metal deactivator in the form of the 80% solution of
N,N'-disalicylidene-1,2-propanediamine as in Example 1;
"Disp." is Chevron OFA 425B ashless dispersant in the form of a SO% solution
as in Example 3;
"Amine" in the form of N-cyclohexyl-N,N-dimethylamine stabiliser; and
"Dil." is diluent in the form of heavy aromatic naphtha.
All tests involving use of an additive mixture were run at a total additive
concentration of 500 ppm in the fuel. In the table "--" signifies "none", the
numerical
values for the additive components represent the weight percentage of the
component in the form listed above, and the results are expressed in terms of
milli-
grams of deposit per 100 milliliters of fuel. Test Nos. 1-6 were performed in
Fuel
A and Test Nos. 7-13 in Fuel B.
Case EL-6250
29 2~~J~.~~~
Thermal Tests
Oxidative
Stability
Test Ca Metal Deposits,
No. MMT Due. Deact. D1SD. Amine Dil m mL
1 __ __ __ __ __ __ 0.28
2 -- -- -- -- -- -- 0.34
3 4 6 -- -- 20 70 1.83
4 4 6 1.2 6.9 5.2 76.7 2.88
S 4 6 1.6 9.2 9.2 70 0.09
6 4 6 1.6 6.9 5.2 76.3 0.23
7 __ _- __ __ __ __
1.31
g __ __ __ __ __ __ 1.86
9 4 6 -- 7.5 6.9 75.6 2.06
10 4 6 1.2 6.9 6.9 75 0.34
11 4 6 1.2 6.9 5.2 76.7 0.09
12 4 6 1.6 9.2 9.4 70 0.03
13 4 6 1.6 9.2 9.2 70 0.06
It will be seen from the results in the above table that in the relatively
stable
Fuel A the combination of the manganese compound and the calcium-containing
detergent (Test No. 3) caused a significant loss in fuel stability as compared
to the
additive-free fuel (Test Nos. 1 and 2). It will also be noted that this fuel
destabili-
sation occurred notwithstanding the presence in the fuel of a relatively high
concentration of N-cyclohexyl-N,N-dimethylamine, a known fuel stabiliser. From
Test No. 4 it is seen that in this particular fuel, 1.2% of the metal
deactivator blend
in the additive mixture (at 500 ppm) was insufficient to combat the fuel
destabil-
isation. On the other hand, Test Nos. 5 and 6 show that 1.6% of the metal
deactivator in the additive mixture (at 500 ppm) greatly increased the
stability of the
fuel composition. Thus in Fuel A there is a threshhold concentration in the
systems
tested at 500 ppm falling between these 1.2% and 1.6% additive proportions.
In the less stable fuel (Fuel B), it is seen from Test No. 9 that once again
the
combination of the manganese compound and the calcium-containing detergent
Case EL-6250
30 ~~ ~:~ ~ ~ ~.
resulted in a further loss of fuel stability as compared to the additive-free
fuel (Tests
7 and 8). And from Test Nos. 10 through I3 it is seen that in Fuel B both 1.2%
and
1.6% of the metal deactivator in the additive mixtures conferred at the 500
ppm
additive mixture level, very substantial improvements in fuel stability. Thus
in Fuel
B the threshhold concentration in the system at 500 ppm corresponds to less
than
1.2% of the metal deactivator in the additive composition.
The effectiveness and advantageous characteristics of the compositions of this
invention are illustrated by the results of a number of other standardised
tests. For
example, an 81 kW gas oil-fired hot water boiler was operated with a flue gas
temperature of 207 ° C, a carbon dioxide flue gas content of 12.I% and
a carbon
monoxide flue gas content of above 100 ppm. The base heating gas oii was as
specified in Example 14. Operation of the boiler on the additive-free gas oil
gave
a Bacharach soot number of 4.60 whereas the same gas oil containing 500 ppm of
the
additive composition of Example 4 gave a Bacharach soot number of 2.70, a 41%v
reduction. Measurements of the acidity of the soot (an average of 4
determinations)
showed that the clear base gas oil produced a soot with an average pH of 4.05.
In
contrast the soot from the fuel of this invention had a pH averaging 7.06.
Standard CFR engine tests (ASTM D613) were conducted using two different
diesel fuels having cetane values of 52.7 (Fuel A) and 52.5 (Fuel B),
respectively.
Addition of 500 ppm of the composition of Example 4 to Fuel A caused no change
in cetane rating. In Fuel B only a slight loss in cetane value (from 52.5 to
51.6)
occurred by addition of 500 ppm of the composition of Example 4.
The same pair of diesel fuels were subjected to standard corrosion tests
(ASTM 665A), both with and without 500 ppm of the additive composition of
Example 4. The results of these tests were as follows:
Rating_Per ASTM 665A
Fuel A without additives D, D
Fuel A with additives A, A
Fuel B without additives B, B+
Fuel B with additive A, A
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31
Diesel fuels both with and without the additive composition of this invention
as set forth in Example 7 were subjected to standard corrosion tests (ASTM
665A)
and (ASTM 665B). The results were as follows:
Rating Per Rating Per
ASTM 665A ASTM 665B
Fuel A without additives C, C E, E
Fuel A with additives A, A E, E
Fuel B without additives B+, B+ D, D
Fuel B with additives A, A D, D
.. The same compositions were subjected to thermal stability tests wherein the
sample is heated at 150 ° C for 90 minutes, filtered through a filter
and the
reflectance of the deposit on the filter measured. The rating scale ranges
from 0
(clean) to 20 (black). A rating of 7 or less is considered good. Thermal
oxidative
stability tests according to ASTM D 2274 were also performed on these fuel
composi-
tions. The performance in these tests is expressed in terms of milligrams of
deposit
per 100 milliliters of fuel. The results were as follows:
Thermal
Thermal Oxidative
Stability Stability
!Filter Tests),(ASTM D2274)
Fuel A without additives6 0.15
Fuel A with additives 3 0.17
Fuel B without additives19 4.45
Fuel B with additives 6 0.14
Demulsification tests the same four fuels gave
(ASTM D 1094) on the results
shown below:
Case EL-6250
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Volume of
Interface Separation Aqueous
Rating Rating Phase. mL
Fuel A without additives4 3 17
Fuel A with additives 3 3 18
Fuel B without additives4 3 7
Fuel B with additives 3 3 19
Additional tests were run using a commercially available domestic heating gas
oil in order to determine performance in two different burners. One was a
modern
burner whereas the other was a burner produced fifteen years ago. In each case
the
burners were adjusted to the manufacturer's specifications. The additive
compositions of Examples 4 and 7 were utilised in these tests together with
baseline
runs on the clear base fuel. Measurements were made of the smoke number and
for
carbon monoxide content of the flue gases. The smoke number determinations
involve a scale ranging from 0 to 10, which ratings are applied to a filter
through
which the flue gas was passed during the operation. A rating of 10 means black
and
thus the lower the number, the better. The carbon monoxide ratings are
expressed
in terms of parts per million in the flue gas. The following table summarises
these
data.
Old Burner New Burner
Smoke ~Q, Smoke No.
No. ~Q
Base fuel without additives5.5 80 1 90
Base fuel with additivesa5.5 43 -- --
Base fuel with additivesb4.0 40 0 18
Base fuel with additives'4.5 40 0 20
Base fuel with additivesd3.5 45 0 25
a Additive composition of Example 4 at 500 ppm
b Additive composition of Example 4 at 1000 ppm
c Additive composition of Example 7 at 500 ppm
d Additive composition of Example 7 at 1000 ppm
Case EL-6250
-33-
The above and other test results have indicated that the fuels of this
invention
generally possess enhanced combustion properties (e.g., less smoke, lower soot
acidity) and better thermal stability than the corresponding untreated fuels.
In
addition, use of the fuels of this invention results in the formation of
reduced
amounts of sludge deposits on critical engine or burner parts or surfaces.
Further,
such fuels tend to emit smaller amounts of noxious emissions than the
corresponding
untreated base fuels. Also this invention enables the provision of fuel
compositions
having enhanced demulsification properties and reduced corrosion tendencies
with
minimal interference with other desirable fuel properties. The additive
compositions
of this invention can result in decreased fuel consumption in diesel engines.
The
above data indicate that all fuels do not necessarily respond to the same
extent to
treatment with the additive systems of this invention. Nonetheless, as a
general
proposition, the fuels of this invention do have significantly improved
properties.
It will be seen from the foregoing that this invention includes among its
embodiments methods of improving the combustion characteristics and stability
of
an at least predominantly hydrocarbonaceous liquid fuel which comprises
blending
therewith a minor combustion-improving amount of:
a) at least one fuel-soluble manganese carbonyl compound; and
b) at least one fuel-soluble alkali or alkaline earth metal-containing
detergent;
and a minor stabilising amount of:
c) at least one fuel-soluble metal deactivator of the chelation type.
Such compositions preferably contain one or more of components d), e) and f)
as
described hereinabove.
