EP0525157B1

EP0525157B1 - Fuel composition

Info

Publication number: EP0525157B1
Application number: EP92905026A
Authority: EP
Inventors: Edward C. Mozdzen; Stephen A. Di Biase
Original assignee: Lubrizol Corp
Current assignee: Lubrizol Corp
Priority date: 1991-02-15
Filing date: 1992-01-21
Publication date: 1995-03-01
Anticipated expiration: 2012-01-21
Also published as: EP0525157A1; MX9200591A; IL100920A0; NO923977D0; DE69201538T2; FI924643A0; BR9204777A; DE69201538D1; RU2062781C1; TW239158B; HU9203252D0; JPH05507313A; ES2072143T3; AU654170B2; AU1257692A; HUT64100A; PL296386A1; HK39596A; NO923977L; WO1992014805A1

Abstract

Motor fuel compositions comprising a normally liquid fuel in the gasoline boiling range, and (A) an aminophenol of formula (I) wherein each A is independently H or a hydrocarbyl group, each T is independently H or a hydrocarbyl group of up to about 28 carbon atoms, a, b and c are each independently an integer of at least one with the proviso that the sum of a, b and c does not exceed the unsatisfied valences of Ar; and Ar is a single ring, a fused polynuclear ring or a linked polynuclear ring aromatic moiety having 0 to 3 optional substituents selected from the group consisting essentially of lower alkyl, lower alkoxyl, nitro, carboxy lower alkyl, nitroso, halo and combinations of two or more of said optional substituents; and (B) an amine of general formula (II) wherein R<1> is a hydrocarbyl group containing from about 8 to about 24 carbon atoms, R<2> and R<3> are each independently H, a hydrocarbyl group containing from 1 to about 24 carbon atoms or a group of general formula (III) wherein R<5> is an alkylene group containing from 2 to about 8 carbon atoms, and R<2> and R<3> are as defined hereinabove, each R<4> is independently an alkylene group containing from 2 to about 8 carbon atoms, and each of x, y and z is independently an integer from 0 to about 20. In one embodiment, components (A) and (B) are present in amounts sufficient to provide total intake system cleanliness. In another embodiment, components (A) and (B) are present in amounts sufficient to prevent or to reduce the formation of intake valve deposits or to remove same where they have formed. Methods for providing total intake system cleanliness and preventing or reducing the formation of intake valve deposits or removing same, are disclosed.

Description

This invention is directed to novel fuel compositions for internal combustion engines and to methods for using such fuel compositions.
Over the years, fuels used in internal combustion engines have contained various kinds of additives to improve performance of the fuel or to alleviate problems arising during the use and combustion of fuels in internal combustion engines. During the 1950's and 1960's, engine designers generally focused their efforts towards the development of high-performance engines, with little concern about fuel economy or exhaust emissions. The fuel delivery system for engines of this era involved the use of carburetors to deliver an air-fuel mixture, via a manifold, to the cylinders for combustion. Primary concerns at this time were carburetor icing, adequate octane value, deposit formation on carburetor surfaces, and fuel stability. Additives for fuels such as anti-icing agents, lead-containing fuel additives, detergents, and various antioxidants generally resulted in adequate performance. Deposits in other parts of the fuel delivery system were not of a major concern because such engines were generally tuned to a rich air/fuel ratio allowing for mixture malfunction. Greater power-weight ratios meant that the driver was less apt to notice changes in peak power and fuel economy, and exhaust emissions were not a serious concern at that time.
It wasn't until the energy shortages of the 1970's, and, at about the same time, increased awareness of environmental concerns, that changes directed to purposes other than improving engine output began to receive widespread attention. During this time, and up to the early 1980's, government regulations in the United States and in other countries throughout the world imposed increasingly stringent limitations on exhaust emissions and on fuel consumption. Efforts to comply with these requirements involved various engine modifications, smaller vehicles, smaller engines, and increasingly widespread use of light weight materials. Only minor changes were made to fuel systems during this time other than efforts to control hydrocarbon emissions. During this time, consumers did become aware of the importance of fuel intake system cleanliness to maintain acceptable fuel consumption limits.
By the early 1980's, the carbureted internal combustion engine began to give way to throttle-body fuel injection systems. Such systems are described in United States Patents 4,487,002 and 4,490,792 and in Bowler, SAE Paper 800164. Conventional fuel additives generally provided adequate service for this system.
In response to continuing demands for improved fuel economy, increased performance and reduced exhaust emissions, automobile manufacturers began to utilize even more sophisticated engines. One of the developments was the increased use of high specific output, lean burn engines. To meet the complex demands of increased power, fuel economy, and environmental control, these engines were tuned to operate at or near the lean limit of combustion, i.e., minimum amount of fuel. Lean burn engines require precise management of air-fuel ratios. This resulted in engines much less tolerant of deposits throughout the fuel metering and induction system. Thus, total intake system cleanliness has become an important priority. Further developments in fuel metering and induction systems have resulted in engines that can operate efficiently and provide excellent performance while generating minimal objectionable emissions or emissions that are readily controlled with emission control systems such as catalysts and the like. One such development is the increasingly widespread use of fuel injection systems such as port fuel injection, also known as multi-port fuel injection, in which injectors discharge fuel into an intake runner or intake port. Such injector systems are illustrated in U.S. Patent 4,782,808. Each injector is normally located in close proximity to the intake valve. The injector itself is designed to close tolerances and is subject to fouling, for example, from the fuel itself or because its location, in close proximity to the intake valve, and is in an environment of high temperature resulting in carbon and varnish deposit formation on the injector. Such deposits result in impaired control of fuel metering. When deposits form on the injector tip, the injector may clog or at least the precise fuel spray pattern is disrupted.
Another problem that has arisen is the formation of deposits on the intake valve itself. One of the reasons proposed for the particularly severe formation of deposits in port fuel injections engines is that the fuel is sprayed upon the hot valve surface resulting in formation of carbon deposits on the valve itself.
While earlier engines were sometimes prone to the formation of deposits throughout the intake system, including on the intake valve itself, the less demanding requirements of engines operating on a rich fuel mixture tended to mask the detrimental effect on driveability. Today's more sophisticated engines often are very intolerant of such deposits, resulting in severe driveability problems such as rough idling, hesitation on start up, power loss and stalling.
The use of large amounts of conventional dispersing additives in an attempt to overcome some of these stated problems often resulted in increased deposits on the intake valve and also in valve sticking. It has been proposed that degradation of the fuel additive results in deposits that impair movement of the valve.
Accordingly, efforts are continuing to provide means for maintaining intake system cleanliness or to clean up intake systems which are already contaminated.
US-A-4,663,063 discloses a composition for use as an additive in a two-cycle engine which comprises an amino compound which is not an amino phenol optionally in combination with a further amino compound which may be an amino phenol. However, it is an essential feature of this composition that an alkyl phenol is present.
We have now found it possible:
to provide novel fuel compositions;
to provide novel fuel compositions that provide total intake system cleanliness;
to provide novel fuel compositions for use in port fuel injected engines that prevent or reduce the formation of intake valve deposits;
to provide novel fuel compositions that meet at least one of the above-stated aims and do not contribute towards valve-sticking;
to provide a method for maintaining total intake system cleanliness in a gasoline-fueled internal combustion engine; and
to provide a method for preventing or reducing the formation of intake valve deposits in a port fuel injected engine, or for removing such deposits where they have formed.
Other aims are mentioned hereinbelow or will be apparent to one skilled in the applicable art upon reading the disclosure.
We have also found it possible to provide an additive composition comprising more than one additive, wherein the additives do not interact with each other in an adverse manner, and which provide an unexpected improvement in intake system cleanliness and reduction or elimination of intake valve deposits.
According to one aspect of the present invention there is provided a motor fuel composition comprising a normally liquid fuel in the gasoline boiling range;

(A) an amino phenol of the general formula
wherein each A is independently H or a substantially saturated hydrocarbon-based group, each T is independently H or a hydrocarbyl group of up to about 28 carbon atoms, a, b and c are each independently an integer of at least one with the proviso that the sum of a, b and c does not exceed the unsatisfied valences of Ar; and Ar is a single ring, a fused polynuclear ring or a linked polynuclear ring aromatic moiety having 0 to 3 optional substituents selected from the group consisting essentially of lower alkyl, lower alkoxyl, nitro, carboxy lower alkyl, nitroso, halo and combinations of two or more of said optional substituents; and
(B) an amine of the general formula
wherein R¹ is a hydrocarbyl group containing from 8 to 24 carbon atoms, R² and R³ are each independently H, a hydrocarbyl group containing from 1 to 24 carbon atoms or a group of the general formula
wherein R⁵ is an alkylene group containing from 2 to 8 carbon atoms, and R² and R³ are as defined hereinabove, each R⁴ is independently an alkylene group containing from 2 to 8 carbon atoms, and each of x, y and z is independently an integer from 0 to 20;
with the proviso that the composition does not contain an alkyl phenol.

In one embodiment, components (A) and (B) are present in amounts sufficient to provide total intake system cleanliness. In another embodiment, components (A) and (B) are present in amounts sufficient to prevent or to reduce the formation of intake valve deposits or to remove same where they have formed. The presence of an additional component (C), a fluidizer oil, has been found to be helpful in providing enhanced detergency and in reducing valve-sticking. Methods for providing total intake system cleanliness and preventing or reducing the formation of intake valve deposits or removing same, are disclosed.
Various preferred features and embodiments of the present invention will now be described by way of non-limiting example.

(A) The Amino Phenols

The Aromatic Moiety Ar

The aromatic moiety, Ar, of Formula I can be a single aromatic nucleus such as a benzene nucleus, a pyridine nucleus, a thiophene nucleus, or a 1,2,3,4-tetrahydronaphthalene nucleus, or a polynuclear aromatic moiety. Such polynuclear moieties can be of the fused type; that is, wherein at least one aromatic nucleus is fused at two points to another nucleus such as is found in naphthalene, anthracene or the azanaphthalenes. Alternatively, such polynuclear aromatic moieties can be of the linked type wherein at least two nuclei (either mono- or polynuclear) are linked through bridging linkages to each other. Such bridging linkages can be chosen from carbon-to-carbon single bonds, ether linkages, keto linkages, sulfide linkages, polysulfide linkages of 2 to 6 sulfur atoms, sulfinyl linkages, sulfonyl linkages, methylene linkages, alkylene linkages, di-(lower alkyl)methylene linkages, lower alkylene ether linkages, alkylene keto linkages, lower alkylene sulfur linkages, lower alkylene polysulfide linkages of 2 to 6 carbon atoms, amino linkages, polyamino linkages and mixtures of such divalent bridging linkages. In certain instances, more than one bridging linkage can be present in Ar between aromatic nuclei. For example, a fluorene nucleus has two benzene nuclei linked by both a methylene linkage and a covalent bond. Such a nucleus may be considered to have 3 nuclei but only two of them are aromatic. Normally, Ar will contain only carbon atoms in the aromatic nuclei per se (plus any lower alkyl or alkoxy substituent present).
The number of aromatic nuclei, single, fused, linked or both, in Ar can play a role in determining the integer values of a, b and c in Formula I. For example, when Ar contains a single aromatic nucleus, a, b and c are each independently 1 to 4. When Ar contains two aromatic nuclei, a, b and c can each be an integer of 1 to 8. With a tri-nuclear Ar moiety, a, b and c can each be an integer of 1 to 12. For example, when Ar is a biphenyl or a naphthyl moiety, a, b and c can each independently be an integer of 1 to 8. The values of a, b and c are obviously limited by the fact that their sum cannot exceed the total unsatisfied valences of Ar.
The single ring aromatic nucleus which can be the Ar moiety can be represented by the general formula

ar(Q)_m

wherein ar represents a single ring aromatic nucleus (e.g., benzene) of 4 to 10 carbons, each Q independently represents a lower alkyl group, lower alkoxy group, nitro group, nitroso group, carboxy lower alkyl group or halogen atom, and m is 0 to 3. As used in this specification and appended claims, "lower" refers to groups having 7 or less carbon atoms such as lower alkyl and lower alkoxyl groups. Halogen atoms include fluorine, chlorine, bromine and iodine atoms; usually, the halogen atoms are fluorine and chlorine atoms.
Specific examples of single ring Ar moieties are the following:

etc., wherein Me is methyl, Et is ethyl, Pr is n-propyl, and Nit is nitro.
When Ar is a polynuclear fused-ring aromatic moiety, it can be represented by the general formula

wherein ar, Q and m are as defined hereinabove, m' is 1 to 4 and
represents a pair of fusing bonds fusing two rings so as to make two carbon atoms part of the rings of each of two adjacent rings. Specific examples of fused ring aromatic moieties Ar are:

etc.
When the aromatic moiety Ar is a linked polynuclear aromatic moiety, it can be represented by the general formula

wherein w is an integer of 1 to 20, ar is as described above with the proviso that there are at least 3 unsatisfied (i.e., free) valences in the total of ar groups, Q and m are as defined hereinbefore, and each Lng is a bridging linkage individually chosen from carbon-to-carbon single bonds, ether linkages (e.g. -O-), keto linkages (e.g.,

sulfide linkages (e.g., -S-), polysulfide linkages of 2 to 6 sulfur atoms (e.g., -S₂-₆-), sulfinyl linkages (e.g., -S(O)-), sulfonyl linkages (e.g., -S(O)₂-), lower alkylene linkages (e.g., -CH₂-, -CH₂-CH₂-,

etc.), di(lower alkyl)-methylene linkages (e.g., CR°₂-), lower alkylene ether linkages (e.g., -CH₂O-, -CH₂O-CH₂-, -CH₂-CH₂O-, -CH₂CH₂OCH₂CH₂-,

etc.), lower alkylene sulfide linkages (e.g., wherein one or more -O-'s in the lower alkylene ether linkages is replaced with an -S- atom), lower alkylene polysulfide linkages (e.g., wherein one or more -O-'s is replaced with a -S₂-₆ group), amino linkages (e.g.,

where alk is lower alkylene, etc.), polyamino linkages (e.g., -N(alkN)₁₋₁₀, where the unsatisfied free N valences are taken up with H atoms or R° groups), and mixtures of such bridging linkages (each R° being a lower alkyl group). It is also possible that one or more of the ar groups in the above-linked aromatic moiety can be replaced by fused nuclei such as ar
ar
_m,.
Specific examples of linked moieties are:

etc.
Usually all these Ar moieties have no substituents except for the A, -OH and -NT groups (and any bridging groups).
For reasons such as cost, availability, performance, etc., the Ar moiety is normally a benzene nucleus, lower alkylene bridged benzene nucleus, or a naphthalene nucleus. Thus, a typical Ar moiety is a benzene or naphthalene nucleus having 3 to 5 unsatisfied valences, so that one or two of said valences may be satisfied by a hydroxyl group with the remaining unsatisfied valences being, insofar as possible, either ortho or para to a hydroxyl group. Preferably, Ar is a benzene nucleus having at least 3 unsatisfied valences so that one can be satisfied by a hydroxyl group with the remaining 2 or 3 being either ortho or para to the hydroxyl group.

The Group A

The aminophenols of the present invention contain, directly bonded to the aromatic moiety Ar, at least one group A, which, independently, may be H or a hydrocarbyl group. In one embodiment, each group A is independently H or an alkyl or alkenyl group having up to about 18 carbon atoms. Preferably, at least one A is a hydrocarbyl group. More than one hydrocarbyl group can be present, but usually no more than two or three hydrocarbyl groups are present for each aromatic nucleus in the aromatic moiety Ar. Preferably, at least one A group is a hydrocarbyl group containing from 9 to 750 carbons. More often, the hydrocarbyl group A has at least 30 to 400 carbon atoms, more typically, at least 50 carbon atoms and up to 750, more typically, up to 300 carbon atoms. In an especially preferred embodiment, each non-hydrogen A is an aliphatic hydrocarbyl group.
When the group A is an alkyl or alkenyl group having from 2 to 28 carbon atoms, it is typically derived from the corresponding olefin; for example, a butyl group is derived from butene, an octyl group is derived from octene, etc. when A is a hydrocarbyl group having at least about 30 carbon atoms, it is frequently an aliphatic group made from homo- or interpolymers (e.g., copolymers, terpolymers) of mono- and di-olefins having 2 to 10 carbon atoms, such as ethylene, propylene, butene-1, isobutene, butadiene, isoprene, 1-hexene or 1-octene. Typically, these olefins are 1-mono olefins such as homopolymers of ethylene. These aliphatic hydrocarbyl groups may also be derived from halogenated (e.g., chlorinated or brominated) analogs of such homo- or interpolymers. A groups which are hydrocarbyl can, however, be derived from other sources, such as monomeric high molecular weight alkenes (e.g., 1-tetracontene) and chlorinated analogs and hydrochlorinated analogs thereof, aliphatic petroleum fractions, particularly paraffin waxes and cracked and chlorinated analogs and hydrochlorinated analogs thereof, white oils, synthetic alkenes such as those produced by the Ziegler-Natta process (e.g., poly(ethylene) greases) and other sources known to those skilled in the art. Any unsaturation in the A groups may be reduced or eliminated by hydrogenation according to procedures known in the art before the nitration step described hereinafter.
As used herein, the term "hydrocarbyl group" denotes a group having a carbon atom directly attached to the remainder of the molecule and having a predominantly hydrocarbon character within the context of this invention. Thus, the term "hydrocarbyl" includes hydrocarbon, as well as substantially hydrocarbon, groups. Substantially hydrocarbon describes groups, including hydrocarbon based groups, which contain non-hydrocarbon substituents, or non-carbon atoms in a ring or chain, which do not alter the predominately hydrocarbon nature of the group.
Hydrocarbyl groups can contain up to three, preferably up to one, non-hydrocarbon substituent, or non-carbon heteroatom in a ring or chain, for every ten carbon atoms provided this non-hydrocarbon substituent or non-carbon heteroatom does not significantly alter the predominantly hydrocarbon character of the group. Those skilled in the art will be aware of such heteroatoms, such as oxygen, sulfur and nitrogen, or substituents, which include, for example, hydroxyl, halo (especially chloro and fluoro), alkoxyl, alkyl mercapto or alkyl sulfoxy.
Examples of hydrocarbyl groups include, but are not necessarily limited to, the following:

(1) hydrocarbon substituents, that is, aliphatic (e.g., alkyl or alkenyl), alicyclic (e.g., cycloalkyl, cycloalkenyl) substituents, aromatic-, aliphatic- and alicyclic-substituted aromatic substituents, for example, as well as cyclic substituents wherein the ring is completed through another portion of the molecule (that is, for example, any two indicated substituents may together form an alicyclic radical);
(2) substituted hydrocarbon substituents, that is, those substituents containing non-hydrocarbon groups which, in the context of this invention, do not alter the predominantly hydrocarbon substituent; those skilled in the art will be aware of such groups (e.g., halo (especially chloro and fluoro), hydroxy, alkoxy, mercapto, alkylmercapto, nitro, nitroso or sulfoxy);
(3) hetero substituents, that is, substituents which will, while having a predominantly hydrocarbon character within the context of this invention, contain atoms other than carbon present in a ring or chain otherwise composed of carbon atoms. Suitable heteroatoms will be apparent to those of ordinary skill in the art and include, for example, sulfur, oxygen, nitrogen and such substituents as, e.g., pyridyl, furyl, thienyl or imidazolyl. In general, no more than about 2, preferably no more than one, non-hydrocarbon substituent or non-carbon atom in a ring moiety, will be present for every ten carbon atoms in the hydrocarbyl group. Usually, however, the hydrocarbyl groups are purely hydrocarbon and contain no such non-hydrocarbon groups or substituents.

Preferably, hydrocarbyl groups A are substantially saturated. By substantially saturated it is meant that the group contains no more than one carbon-to-carbon unsaturated bond for every ten carbon-to-carbon single bonds present. Usually, they contain no more than one carbon-to-carbon non-aromatic unsaturated bond for every 50 carbon-to-carbon bonds present.
Preferably, hydrocarbyl groups A of the aminophenols of this invention are also substantially aliphatic in nature, that is, they contain no more than one non-aliphatic moiety (cycloalkyl, cycloalkenyl or aromatic) group of six or less carbon atoms for every ten carbon atoms in the A group. Usually, however, the A groups contain no more than one such non-aliphatic group for every fifty carbon atoms, and in many cases, they contain no such non-aliphatic groups at all; that is, the typical A group is purely aliphatic. Typically, these purely aliphatic A groups are alkyl or alkenyl groups.
Specific non-limiting examples of substantially saturated hydrocarbyl A groups are: methyl, tetra (propylene), nonyl, triisobutyl, oleyl, tetracontanyl, henpentacontanyl, a mixture of poly(ethylene/propylene) groups of 35 to 70 carbon atoms, a mixture of the oxidatively or mechanically degraded poly(ethylene/propylene) groups of about 35 to about 70 carbon atoms, a mixture of poly(propylene/1-hexene) groups of 80 to 150 carbon atoms, a mixture of poly(isobutene) groups having between 20 and 32 carbon atoms, and a mixture of poly(isobutene) groups having an average of 50 to 75 carbon atoms. A preferred source of hydrocarbyl groups A are polybutenes obtained by polymerization of a C₄ refinery stream having a butene content of 35 to 75 weight percent and isobutene content of 15 to 60 weight percent in the presence of a Lewis acid catalyst such as aluminum trichloride or boron trifluoride. These polybutenes contain predominantly (greater than 80% of total repeating units) isobutene repeating units of the configuration

The attachment of a hydrocarbyl group A to the aromatic moiety Ar of the aminophenols of this invention can be accomplished by a number of techniques well known to those skilled in the art. One particularly suitable technique is the Friedel-Crafts reaction, wherein an olefin (e.g., a polymer containing an olefinic bond), or halogenated or hydrohalogenated analog thereof, is reacted with a phenol in the presence of a Lewis acid catalyst. Methods and conditions for carrying out such reactions are well known to those skilled in the art. See, for example, the discussion in the article entitled, "Alkylation of Phenols" in "Kirk-Othmer Encyclopedia of Chemical Technology", Third Edition, Vol. 2, pages 65-66, Interscience Publishers, a division of John Wiley and Company, N.Y., and U.S. Patents 4,379,065; 4,663,063; and 4,708,809. Other equally appropriate and convenient techniques for attaching the hydrocarbon-based group R to the aromatic moiety Ar will occur readily to those skilled in the art.
As will be appreciated from inspection of Formula I, the aminophenols of this invention contain at least one of each of the following substituents: a hydroxyl group, an A group as defined above, and an amino group, -NT₂. Each of the foregoing groups must be attached to a carbon atom which is a part of an aromatic nucleus in the Ar moiety. They need not, however, each be attached to the same aromatic ring if more than one aromatic nucleus is present in the Ar moiety.

The Amino Groups -NT₂

The aminophenol of the instant invention contains at least one substituent of the formula -NT₂. Each T is independently H or a hydrocarbyl group having up to about 28 carbon atoms. In one embodiment, each T is independently H or an alkyl or alkenyl group. The alkyl or alkenyl groups contain from 1 to 28 carbon atoms, more often from 1 to 18 carbon atoms. In one preferred embodiment, at least one T is H with the other T being H or alkyl or alkenyl. In a most preferred embodiment, both T are H.
The subscript c indicates the number of amino groups that may be present as substituents on the Ar group. There will be at least one such amino group substituent, and there may be more, depending on the values of the subscripts a and b. Preferably, c is a number ranging from 1 to 5. In a preferred embodiment, c is one.
The subscript b indicates the number of -OH groups appearing as substituents on the aromatic moiety Ar. The subscript b must be at least one; however, it may be a number greater than 1 as defined hereinabove. The maximum number of -OH groups that may appear on the aromatic moiety Ar depends upon the values for subscripts a and b. Preferably, there will be from 1 to 5 -OH groups as substituents on Ar. In an especially preferred embodiment, there will be but one OH substituent on Ar, that is, the subscript b equals one.
In a preferred embodiment, the aminophenols of this invention contain one each of the foregoing substituents -OH and -NT₂ (i.e., b and c are each 1), one A is an aliphatic hydrocarbon-based group with the remaining A groups being H, and but a single aromatic ring, most preferably benzene. An especially preferred class of aminophenols can be represented by the general formula

wherein the R' group is a substantially saturated hydrocarbyl group of 30 to 400 aliphatic carbon atoms located ortho or para to the hydroxyl group, R'' is a lower alkyl, carboxy lower alkyl, lower alkoxyl, nitro group or halo group and p is 0 or 1. Usually p is 0 and R' is a substantially saturated, purely hydrocarbon aliphatic group. Often it is an alkyl or alkenyl group para to the -OH substituent. Often there is but one amino group, -NH₂ in these preferred aminophenols but there can be two.
In a still more preferred embodiment of this invention, the aminophenol is of the general formula

wherein R' is derived from homopolymerized or interpolymerized C₂₋₁₀ 1-olefins and has an average of from 30 to 400 aliphatic carbon atoms and R'' and p are as defined above. Usually R' is derived from polymerized ethylene, propylene, butylenes and mixtures thereof. Typically, it is derived from polymerized butenes. Often R' has at least about 50 aliphatic carbon atoms and p is 0.
The aminophenols of the present invention can be prepared by a number of synthetic routes. These routes can vary in the type of reactions used and the sequence in which they are employed. For example, an aromatic hydrocarbon, such as benzene, can be alkylated with an alkylating agent such as a polymeric olefin to form an alkylated aromatic intermediate. This intermediate can then be nitrated, for example, to form a polynitro intermediate. The polynitro intermediate can in turn be reduced to a diamine, which can then be diazotized and reacted with water to convert one of the amino groups into a hydroxyl group and provide the desired aminophenol. Alternatively, one of the nitro groups in the polynitro intermediate can be converted to a hydroxyl group through fusion with caustic to provide a hydroxy-nitro alkylated aromatic which can then be reduced to provide the desired aminophenol.
Another useful route to the aminophenols of this invention involves the alkylation of a phenol with an olefinic alkylating agent to form an alkylated phenol. This alkylated phenol can then be nitrated to form an intermediate nitro phenol which can be converted to the desired aminophenol by reducing at least some of the nitro groups to amino groups.
Techniques for alkylating phenols are well known to those skilled in the art as the above-noted article in Kirk-Othmer "Encyclopedia of Chemical Technology" demonstrates. Techniques for nitrating phenols are also known. See, for example, in Kirk-Othmer "Encyclopedia of Chemical Technology", Second Edition, Vol. 13, the article entitled "Nitrophenols", page 888 et seq., as well as the treatises "Aromatic Substitution; Nitration and Halogenation" by P. B. D. De La Mare and J. H. Ridd, N. Y., Academic Press, 1959; "Nitration and Aromatic Reactivity" by J. G. Hogget, London, Cambridge University Press, 1961; and "The Chemistry of the Nitro and Nitroso Groups", Henry Feuer, Editor, Interscience Publishers, N. Y., 1969, and U.S. Patents 4,347,148; 4,320,020 and 4,379,065.
Aromatic hydroxy compounds can be nitrated with nitric acid, mixtures of nitric acid with acids such as sulfuric acid or boron trifluoride, nitrogen tetraoxide, nitronium tetrafluoroborates and acyl nitrates. Generally, nitric acid of a concentration of, for example, 30-90% is a convenient nitrating reagent. Substantially inert liquid diluents and solvents such as acetic or butyric acid can aid in carrying out the reaction by improving reagent contact.
Conditions and concentrations for nitrating hydroxy aromatic compounds are also well known in the art. For example, the reaction can be carried out at temperatures of -15°C to 150°C, usually between 25-75°C, for a period of time sufficient to attain the desired degree of nitration.
Generally, depending on the particular nitrating agent 0.5-4 moles of nitrating agent is used for every mole of aromatic nucleus present in the hydroxy aromatic intermediate to be nitrated. If more than one aromatic nucleus is present in the Ar moiety, the amount of nitrating agent may be increased proportionally according to the number of such nuclei present. Up to about a 5-molar excess of nitrating agent (per "single ring" aromatic nucleus) may be used when it is desired to drive the reaction forward or carry it out rapidly.
Reduction of aromatic nitro compounds to the corresponding amines is also well known. See, for example, the article entitled "Amines by Reduction" in Kirk-Othmer "Encyclopedia of Chemical Technology", Third Edition, Vol. 3, pages 335-376. Generally, such reductions can be carried out with, for example, hydrogen, carbon monoxide or hydrazine, (or mixtures of same) in the presence of metallic catalysts, when needed or useful, such as palladium, platinum and its oxides, nickel or copper chromite. Co-catalysts such as alkali or alkaline earth metal hydroxides or amines (including aminophenols) can be used in these catalyzed reductions.
Reduction can also be accomplished through the use of reducing metals in the presence of acids, such as hydrochloric acid. Typical reducing metals are zinc, iron and tin or salts thereof.
Nitro groups can also be reduced in the Zinin reaction, which is discussed in "Organic Reactions", Vol. 20, John Wiley & Sons, N.Y., 1973, page 455 et seq. Generally, the Zinin reaction involves reduction of a nitro group with divalent negative sulfur compounds, such as alkali metal sulfides, polysulfides and hydrosulfides.
The nitro groups can be reduced by electrolytic action; see, for example, the "Amines by Reduction" article, referred to above.
One preferred method for obtaining the aminophenols of this invention is the reduction of nitro phenols with hydrogen in the presence of a metallic catalyst such as discussed above. This reduction is generally carried out at temperatures of about 15°C-250°C, and hydrogen pressures of 0-2000 psig (101-13,881 kPa). The reaction time for reduction usually varies between 0.5-50 hours. The aminophenol product is obtained by well-known techniques such as distillation, filtration, extraction, and so forth.
Another preferred method for obtaining the aminophenols of this invention is the reduction of nitro phenols with at least one hydrazine source, optionally in the presence of at least one metal-containing hydrazine decomposition catalyst.
The hydrazine source used in the present invention is hydrazine, a hydrazine compound or mixture of compounds which are capable of producing hydrazine in sufficient quantities to react with the nitro phenol. Hydrazine, hydrazine compounds and many hydrazine sources are known to those of skill in the art. See, for example, the book entitled "Hydrazine" by Charles C. Clark, published by the Mathieson Chemical Corporation of Baltimore, Maryland (1953), particularly pages 31 through 71 and 120 through 124; and the book entitled "The Chemistry of Hydrazine" by L. F. Audrieth and B. A. Ogg, published by John Wiley and Son, New York (1951), especially pages 209 through 223.
For reasons of economy and ease of handling, hydrazine and particularly its solutions with water and other solvent/diluents is preferred.
In a preferred embodiment, the reaction of the nitro phenol with the hydrazine source takes place in the absence of a metal-containing hydrazine decomposition catalyst. This means the reaction takes place in a reaction mass that does not contain a sufficient amount of metal-containing catalyst to significantly or substantially affect the rate or course of decomposition or reaction of the hydrazine source present. Metals may be present in pure, alloyed or chemically combined form as parts of metallic equipment such as stirrers, pipes, vessels, probes, etc., and in such form they may be in contact with the reaction mass without significantly affecting the course or rate of the decomposition or reaction of the hydrazine source present in the mass. In such cases, for the purpose of the present description, the reaction is said to take place in the absence of a metal-containing hydrazine decomposition catalyst.
The reduction is carried out until at least about 50%, usually about 80%, of the nitro groups present in the nitro intermediate mixture are converted to amino groups. A typical route to the amino phenols of this invention just described can be summarized as

(I) nitrating, with at least one nitrating agent, at least one compound of the formula
wherein A is H or a substantially saturated hydrocarbyl group, c is an integer of at least 1 with the proviso that the sum of a and c does not exceed the unsatisfied valences of Ar'; and Ar' is an aromatic moiety having 0 to 3 optional substituents selected from
lower alkyl, lower alkoxyl, carboxyl lower alkyl, nitro, and halo, or combinations of two or more optional substituents, with the provisos that (a) Ar' has at least one hydrogen atom directly bonded to a carbon atom which is part of an aromatic nucleus, and (b) when Ar' is benzene having only one hydroxyl and only one A group is hydrocarbyl, the hydrocarbyl A group is ortho or para to said hydroxyl substituent,
to form a first reaction mixture containing a nitro intermediate, and
(II) reducing at least about 50% of the nitro groups in said first reaction mixture to amino groups.

Usually this means reducing at least about 50% of the nitro groups to amino groups in a compound or mixture of compounds of the general formula.

wherein each A is independently H or a hydrocarbyl group, a, b and c are each independently an integer of at least 1 with the proviso that the sum of a, b and c does not exceed the unsatisfied valences of Ar; and Ar is an aromatic moiety having 0 to 3 optional substituents selected from the group consisting of lower alkyl, lower alkoxyl, carboxy lower alkyl, halo, or combinations of two or more of said optional substituents; with the proviso that when Ar is a benzene nucleus having only one hydroxyl and only one A which is hydrocarbyl, the hydrocarbyl A group is ortho or para to said hydroxyl substituent.
Techniques for the reduction of nitrated phenols (nitrophenols), and products obtained thereby are described in U.S. Patents 4,320,020; 4,425,138 and 4,724,091 and Canadian Patent 1,096,887.
The following examples are intended to illustrate several aminophenols useful in the compositions of this invention. As will be readily apparent to those skilled in the art, other aminophenols and aminophenols prepared by other techniques can also be used. These examples are not intended to limit the scope of this invention. All parts and percentages are by weight and temperatures are in degrees Celsius unless expressly stated to the contrary.

Example 1

An alkylated phenol is prepared by reacting phenol with polybutene having a number average molecular weight of about 1,000 (vapor phase osmometry) in the presence of a boron trifluoride/phenol catalyst. The catalyst is neutralized and removed by filtration. Stripping of the product filtrate first to 230°/760 torr (101 kPa) (vapor temperature), then to 205°/50 torr (6.6 kPa) (vapor temperature), provides purified alkylated phenol as a residue.
To a mixture of 265 parts of purified alkyl phenol, 176 parts blend mineral oil and 42 parts of petroleum naphtha having a boiling point of approximately 20° is slowly added a mixture of 18.4 parts concentrated nitric acid (69-70%) and 35 parts water. The reaction mixture is stirred for 3 hours at about 30-45°, stripped to 120°/20 torr (2.6 kPa) (vapor temperature) and filtered to provide an oil solution of the desired nitro phenol intermediate.
A mixture of 1500 parts of the above intermediate, 642 parts of isopropanol and 7.5 parts of a nickel on Kieselguhr catalyst is charged to an autoclave under a nitrogen atmosphere. After purging and evacuation with nitrogen three times, the autoclave is pressured to 100 psig. (790 kPa) with hydrogen and stirring is begun. The reaction mixture is held at 96° for a total of 14.5 hours while a total of 1.66 moles of hydrogen is fed to it. After purging with nitrogen three times, the reaction mixture is filtered and the filtrate stripped to 120°/18 torr (2.3 kPa). Filtration provides the desired aminophenol product as an oil solution.

Example 2

A mineral oil solution (1900 parts) of an alkylated, nitrated phenol as described in Example 1 containing 43% mineral oil is heated under a nitrogen atmosphere to 145°. Then, 70 parts of hydrazine hydrate is slowly added to the mixture over 5 hours while its temperature is held at about 145°. The mixture is then heated to 160° for one hour while 56 parts of aqueous distillate is collected. An additional 7 parts of hydrazine hydrate is added and the mixture is held at 140° for an additional hour. Filtration at 130° provides an oil solution of the desired product containing 0.5% nitrogen.
Additional aminophenols useful as component A of the compositions of this invention are illustrated in Table A.

(B) The Amine

Amines useful as Component (B) of the fuel compositions of this invention are amines as defined hereinabove by the general formula (II). They include mono- and polyamines, and may be substantially hydrocarbon-based amines, hydroxy amines, ether amines, amines containing one or more alkoxy groups and others.
In one preferred embodiment, each of x, y and z of general formula (II) is zero. Such amines are substantially hydrocarbon amines including primary hydrocarbon amines wherein R¹ is alkyl or alkenyl having from 8 to 24 carbon atoms, preferably from 14 to 18 carbon atoms, and R² and R³ are each H.
Representative examples of primary alkyl amines are those known as aliphatic primary fatty amines and commercially known as "Armeen" primary amines (products available from Armak Chemicals, Chicago, Ill.). Typical fatty amines include alkyl amines such as N-hexylamine, N-octylamine, N-decylamine, N-dodecylamine, N-tetradecylamine, N-pentadecylamine, N-hexadecylamine or N-octadecylamine(stearyl amine). These Armeen primary amines are available in both distilled and technical grades. These amines are also available under the tradename "Adogen" available from Sherex.
Primary alkenyl amines comprise olefinic unsaturation in the hydrocarbon group. Thus, the R¹ group may contain one or more olefinic unsaturated sites depending on the length of the chain, usually no more than one double bond per 10 carbon atoms. Representative amines are dodecenylamine, myristoleyamine, palmitoleylamine, oleylamine and linoleylamine. Such unsaturated amines also are available under the Armeen and Adogen tradenames.
Also suitable are mixed fatty primary amines such as soya amine, coco amine, tallow amines, C₂₀₋₂₂ amines, and others. These amines are also available under the Armeen and Adogen tradenames, such as Armeen S, Armeen-T, Adogen 101, Adogen 160 and others.
Another class of useful primary hydrocarbon amines are the tertiary alkyl amines. In this case the carbon atom directly attached to the amino nitrogen is a tertiary carbon atom. Each substituent on this carbon atom is a hydrocarbyl group, preferably an alkyl or alkenyl group. Preferably one of the substituents is an alkyl group having from 5 to 25 carbon atoms, and the other two substituents are lower alkyl, that is, having from 1 to 7 carbons, preferably 1 to 3. In a preferred embodiment, one of the substituents is alkyl having from about 5 to about 19 carbons and the other two substituents are methyl groups. Such tertiary alkyl primary amines include t-octyl amine and mixtures of isomeric amines in the C₁₂₋₁₄ and C₁₈₋₂₂ range and are commercially available under the tradename "Primene" (available from Rohm & Haas, Philadelphia, PA).
These hydrocarbon amines also include secondary amines, where one of R² or R³ is not H, and tertiary amines where neither R² nor R³ is H.
Secondary amines include dialkyl amines, for example, where R¹ is a hydrocarbyl group having from 8 to 24 carbon atoms, preferably from 14 to 18 carbon atoms, and more preferably alkyl or alkenyl, and one of R² and R³ is a hydrocarbyl group of 1 to 24 carbon atoms. In one embodiment R¹ and one of R² or R³ are independently alkyl or alkenyl groups having from 8 to 18 carbon atoms. In another embodiment, R¹ is alkyl or alkenyl of 8 to 18 carbons and one of R² or R³ is alkyl or alkenyl from 1 to 9 carbon atoms, such as methyl, butyl, propyl, isopropyl, octyl, etc.
Secondary hydrocarbon amines also include those where one of R² or R³ is a group of general formula (III), wherein y and z are both zero and R⁵ and R² and R³ are as defined hereinabove. These amines include fatty diamines such as fatty polyamine diamines (including mono- or dialkyl, symmetrical or asymmetrical ethylene diamines, propane diamines (1,2, or 1,3), and polyamine analogs of the above. Suitable commercial fatty polyamines are "Duomeen C" (N-coco-1,3-diaminopropane), "Duomeen S" (N-soya-1,3-diaminopropane), "Duomeen T" (N-tallow-1,3-diaminopropane), or "Duomeen O" (N-oleyl-1,3-diaminopropane). "Duomeens" are commercially available diamines described in Product Data Bulletin No. 7-10R1 of Armak Chemical Co., Chicago, Ill.).
Suitable hydrocarbon based amines also include tertiary amines. These amines are those where R¹ and both R² and R³ are hydrocarbyl groups as defined hereinabove, and x, y and z are all zero. Preferably, R¹ is alkyl or alkenyl, especially containing from 14 to 18 carbon atoms, In one embodiment, both R² and R³ are fatty groups containing from 8 to 24 carbons, preferably up to about 18 carbons. Representative tertiary amines are tri(C₈₋₁₀)amine, tri-hydrogenated tallow amine, di-stearyl methyl amine, tri-tridecyl amine and others, all available under the Adogen tradename.
Suitable tertiary hydrocarbon amines also include those where neither R² nor R³ is H, and at least one of these is a group of general formula (III) wherein y and z are each Zero. Thus, at least one of the amine groups is a tertiary amine group, and there may be other amine groups which are primary, secondary or tertiary, depending upon the definition of the various substituent groups in formula III.
Ether amines are also useful in the fuel compositions of this invention. Ether amines are those where x in general formula (II) is equal to one. Ether amines may be primary, secondary or tertiary and may be alkoxylated amines, that is, y and z may be greater than zero and R² and R³ may be other than H. Preferably, however, the ether amines are primary or secondary amines or diamines. Exemplary ether amines are those where R¹ is from 8 to 24 carbons, preferably from 8 to 15 carbons and R⁴ is an alkylene group having from 2 to 8 carbons, preferably from 3 to 8 carbons. Most preferably, R¹ ranges from 12 to 15 carbon atoms and R⁴ contains 3 carbon atoms.
Ether amines are commercially available, for example, under the tradename Adogen (Sherex Chemical Co.) or Surfam (Mars Chemical Co., Atlanta, GA). Exemplary are C₁₃ ether amine (Adogen 183), Adogen 184 (C₁₄ ether amine), Surfam P14AB (branched C₁₄ ether amine), all of which are propane amines, or Adogen 583 (N-(tridecylether propyl) propane diamine) which is a propane diamine.
In another embodiment, at least one of y and z is not zero, and x may be zero or up to 20, preferably zero. These amines, depending on the values of R² and R³ may be secondary or tertiary amines. Preferably, the group R¹ is alkyl or alkenyl, having preferably at least 12, more preferably from 14 to 18 carbon atoms, and x equals zero.
When one of y or z is zero, the amine is a monoalkoxylated amine. Typically, the amine will have the general formula

wherein R¹ and R⁴ are as defined hereinabove, n is an integer of from 1 up to 20, Y is a hydrocarbyl group, preferably alkyl or alkenyl, having from 1 to 24 carbon atoms, preferably from 8 to 18 carbon atoms, and Z has the same meaning as R² or R³ given above. Representative examples include dioleylethanolamine or N-methyl,N-octyl-propanolamine.
Preferably, both y and z are integers greater than zero. These amines may be monoamine or polyamines. These amines may be prepared by reacting a primary amine or a diamine containing one primary and one secondary amine group with an epoxide, such as ethylene oxide or propylene oxide.
Preferably, these are ethoxylated or propoxylated fatty amines, that is, R⁴ is an ethyl or propyl group.
In one embodiment, x equals zero and y and z are integers from 1 to about 20, and each of R² and R³ is H or hydrocarbyl, preferably alkyl or alkenyl. More often both R² and R³ are H, and y and z are integers from 1 to 10, and especially from 1 to 5. Most often y and z are both 1. R¹ is preferably alkyl or alkenyl ranging from 8 to 18 carbons, preferably at least from 12, more often from 14 up to 18 carbon atoms.
Examples of these amines include alkoxylated, preferably ethoxylated or propoxylated fatty amines, such as alkoxylated octyl amine, dodecyl amine, pentadecenyl amine, oleyl amine or tallow amine.
In another embodiment, at least one of R² and R³ is a group of general formula (III) wherein R⁵ is alkylene containing from 2 to 8 carbon atoms, preferably 2 or 3 carbon atoms, y and z are integers as defined hereinabove, preferably zero, and R² and R³ are as defined hereinabove, preferably H.
Examples of these amines include alkoxylated, preferably ethoxylated or propoxylated fatty diamines, such as N-oleyl, N',N'-dihydroxyethyl propane diamine, and soya, coco, tallow and stearyl analogues thereof.
The especially preferred amines are the "Ethomeens" and "Ethoduomeens," a series of commercial mixtures of ethyoxylated fatty amines available from Armak Company. Suitable "Ethomeens" include "Ethomeen C/12," "Ethomeen S/12," "Ethomeen T/12," "Ethomeen 0/12" and "Ethomeen 18/12." In "Ethomeen C/12," "S/12" and "T/12", R¹ is a mixture of alkyl and alkenyl groups derived respectively from coconut oil, soybean oil and tallow, and in "Ethomeen 0/12" and "18/12", it is, respectively, oleyl and stearyl. In the corresponding "Ethoduomeens," R¹ is as defined for the Ethomeens described hereinabove.

(C) The Fluidizer Oil

Fluidizer oils may be used in the fuel compositions of the instant invention. Useful fluidizer oils may be natural oils or synthetic oils, or mixtures thereof. Natural oils include mineral oils, vegetable oils, animal oils, and oils derived from coal or shale. Synthetic oils include hydrocarbon oils such as alkylated aromatic oils, olefin oligomers, esters, including esters of polycarboxylic acids and polyols. For reasons of cost and availability, mineral oils are preferred.
Especially preferred are paraffinic oils containing no more than about 20% unsaturation, that is, no more than 20% of the carbon to carbon bonds are olefinic.
Preferably, the fluidizer oils have a kinematic viscosity ranging from 10 to 20 centistokes (1-2 x 10⁻⁵ m²/s) at 100°C, preferably from 11 to 16 centistokes (1.1-1.6 x 10⁻⁵ m²/s), and most preferably from 11 to 14 centistokes (1.1-1.4 x 10⁻⁵ m²/s). If the viscosity of the fluidizer oil is too high, a problem that may arise is the development of octane requirement increase (ORI) wherein the octane value demands of the engine tend to increase with time of operation.
It has been found that fluidizer oils, when used within the ranges specified herein, together with the aminophenols and amines of this invention, improve detergency and reduce the tendency toward valve sticking. Amounts of the various additives, including individual amounts to be used in the fuel composition, and relative amounts of additives are given hereinafter.

The Fuel

The fuel is a normally liquid fuel in the gasoline boiling range. These fuels are well known to those skilled in the art and are those defined by ASTM Specification D-439. The fuels useful in the compositions of this invention usually contain a major portion of normally liquid fuel such as hydrocarbonaceous petroleum distillate fuel. Fuels useful in the compositions of this invention may also contain non-hydrocarbonaceous material such as alcohols, ethers, organo-nitro compounds and the like (e.g., methanol, ethanol, diethylether, methylethyl ether, nitromethane). These fuels may be derived from vegetable or mineral sources, including, for example, crude petroleum oil, coal, corn, shale and other sources. Examples of suitable fuel mixtures are combinations of gasoline and ethanol, gasoline and nitromethane, etc. Preferred fuels are gasoline, oxygenates, and gasoline-oxygenate blends, all as defined in the aforementioned ASTM D-439 Specification for automotive gasoline. Most preferred is gasoline.
The fuel compositions of the present invention may contain other additives which are well known to those of skill in the art. These can include anti-knock agents such as tetra-alkyl lead compounds, lead scavengers such as halo-alkanes, dyes, antioxidants such as hindered phenols, rust inhibitors such as alkylated succinic acids and anhydrides and derivatives thereof, bacteriostatic agents, gum inhibitors, metal deactivators, demulsifiers and anti-icing agents. The fuel compositions of this inventions may be lead-containing and lead-free fuels. Preferred are lead-free fuels.
As mentioned hereinabove, in one embodiment of this invention, the motor fuel compositions contain a sufficient amount of additives to provide total intake system cleanliness. In another embodiment, they are used in amounts sufficient to prevent or reduce the formation of intake valve deposits or to remove them where they have formed. Preferably, the relative amounts of the aminophenol (A) and the amine (B) range from 150:1 to 1:100 parts by weight. In the fuel, the aminophenol is present from 10 to 150 parts by weight, per thousand barrels of fuel (0.0285-0.4281 kg/m³), and the amine is present at from 1 to 100 pounds by weight, per thousand barrels of fuel (0.0029-0.2854 kg/m³). Optionally, the fuel may contain (C) a fluidizer oil. Preferably, the relative amounts of (A) to (C) ranges from 1:20 to 3:1 by weight. The fuel compositions may contain from about 30 to about 150 pounds by weight, per thousand barrels of fuel of the fluidizer oil (0.0856-0.4281 kg/m³).
While treating levels of the additives used in this invention are described in terms of pounds per thousand barrels (PTB), the PTB values may be multiplied by four to convert the number to parts per million (by weight) (PPM).
The following examples illustrate several fuel compositions of this invention. Unless indicated otherwise, all parts are parts by weight and amounts of aminophenol and other additives are expressed in amounts substantially free of mineral oil diluent. The abbreviation 'PTB' means pounds of additive per thousand barrels of fuel.
Table I illustrates several fuel compositions of the instant invention comprising unleaded gasoline and the indicated amounts of additive in kg/m³ of gasoline.

The following describes an additive concentrate for use in fuels. All parts are parts by weight.

Concentrate
Component	Parts by Weight
Hydrocarbon solvent	9.32
Oleyl amine	3.71
Aminophenol of Example 2	34.59
Fluidizer oil	51.88
C₁₆ substituted succinic anhydride/alkanol amine reaction product	0.31
Salicylidene based metal deactivator	0.19

A fuel composition is prepared employing 1600 PTB (4.5664 kg/m³) (approx. 6400 ppm) of the above concentrate. This treatment is intended to provide "one-tank" cleanup of a dirty fuel delivery system including port fuel injectors and intake valves.
Thus, a gasoline fuel containing from about 200 to about 1000 (0.5708-2.8540 kg/m³), preferably to about 700 PTB (1.9978 kg/m³) of an aminophenol (A) and from 20 to 100 PTB (0.0571-0.2854 kg/m³), preferably to 70 PTB (0.1998 kg/m³) of amine (B) can be used to clean a dirty fuel delivery system which system comprises port fuel injectors and intake valves.
Conventional polymeric group substituted amine detergent additives that were, effective in controlling carburetor deposits often, when used at high treatment levels, were effective for reducing fuel injector deposits. However, this use of a high level of additive led to increased intake valve deposits. It was believed that the combination of dispersants and fluidizers controlled induction system deposits. Unexpectedly, the fuel compositions of this invention provide both total intake system cleanliness and reduce or eliminate intake valve deposits.
An additional problem that arose from the use of polymer group substituted amine dispersants was an adverse interaction between polymeric hydrocarbyl group substituted amine dispersants and various fatty amines such as those identified as component (B) of this invention. The use of these conventional fuel additives to treat a fuel resulted in an increase in intake valve deposits.
When the aminophenols (A) of this invention are employed in gasoline together with the amine component (B), not only is there no apparent adverse interaction resulting in deteriorated levels of performance with respect to cleanliness of the intake system, but also there appears to be a synergistic effect with respect to reduction of intake valve deposits.
The following data demonstrate the unexpected benefit of the fuel compositions of this invention. The fuels were evaluated using the BMW intake valve deposit test.
The fuel evaluation procedure is based on 10,000 miles (16,090 km) of driving in the BMW model 318i vehicle equipped with 1.8L 4-cylinder engine and automatic transmission. The testing is initiated with new, carefully weighed intake valves. This is followed by 16090 km (10,000 miles) of operation with the candidate fuel, and then disassembly of the cylinder head to reweigh the intake valves.
The primary data consists of intake valve deposit ratings and weights, and photographs of the intake valves. The significant data, however, is the actual deposit weight on the intake valves at 16090 km (10,000 miles). Fuels are then classified in one of the three categories based on the following criteria established for the average of the four intake valves:

1) 100 milligrams maximum: meets BMW-NA standards of intake valve cleanliness for unlimited mileage.
2) 250 milligrams maximum: meets BMW-NA standards of intake valve cleanliness up to 50,000 miles (80,450 km).
3) More than 250 milligrams: does not meet BMW-NA standards of intake valve cleanliness.

A gasoline fuel composition was prepared comprising 44 PTB (0.1256 kg/m³) of a polybutene substituted aminoethylethanolamine and 82.5 PTB (0.2355 kg/m³) of a fluidizer oil comprising a residue bright stock. BMW testing resulted in valve deposits ranging from 19.2 mg to 171.5 mg with an average of 94.5 mg.
Several gasoline fuel composition similar to the above but each containing an amount of one of the amines falling within the description of component (B) were prepared. BMW testing of these fuels resulted in an average of about 215 mg deposits.
Two gasoline fuel compositions were prepared comprising 75 PTB (0.2140 kg/m³) (45 PTB (0.1284 kg/m³) on oil-free basis) of an aminophenol as described in Example 1 of this application and 112.5 PTB (0.3211 kg/m³) of a fluidizer oil comprising a residue bright stock. BMW testing resulted in valve deposits ranging from 35.3 to 100.6 mg with an average of 67 mg.
Three gasoline fuel compositions were prepared comprising 80 PTB (0.2283 kg/m³) (48 PTB (0.1370 kg/m³) on oil-free basis) of the amonophenol of Example 1, 120 PTB (0.3425 kg/m³) of fluidizer oil comprising bright stock and each containing an amount of one of the amines falling within the description of component (B). BMW testing of these fuels resulted in an average of about 45 mg valve deposits.
While the invention has been explained in relation to its preferred embodiments, it is to be understood that various modifications thereof will become apparent to those skilled in the art upon reading the specification. Therefore, it is to be understood that the invention disclosed herein is intended to cover such modifications as fall within the scope of the appended claims.

Claims

A process for the preparation of a motor fuel composition comprising a normally liquid fuel in the gasoline boiling range and an amount, sufficient to provide total intake system cleanliness, of
(A) an amino phenol of the general formula
wherein each A is independently H or a hydrocarbyl group, each T is independently H or a hydrocarbyl group of up to
28 carbon atoms, a, b and c are each independently an integer of at least one with the proviso that the sum of a, b and c does not exceed the unsatisfied valences of Ar; and Ar is a single ring, a fused polynuclear ring, or a linked polynuclear ring aromatic moiety, having 0 to 3 optional substituents selected from
lower alkyl, lower alkoxyl, nitro, carboxy lower alkyl, nitroso, halo and combinations of two or more of said optional substituents; and

(B) an amine of the general formula
wherein R¹ is a hydrocarbyl group containing from 8 to 24 carbon atoms, R² and R³ are each independently H, a hydrocarbyl group containing from 1 to 24 carbon atoms or a group of the general formula
wherein R⁵ is an alkylene group containing from 2 to 8 carbon atoms, and R² and R³ are as defined hereinabove, each R⁴ is independently an alkylene group containing from 2 to 8 carbon atoms, and each of x, y and z is independently an integer from 0 to 20;
with the proviso that the composition does not contain an alkyl phenol;
comprising adding (A) and (B) to the fuel.
A process for the preparation of a motor fuel composition for use in a port fuel
injected, gasoline fueled, internal combustion engine comprising a normally liquid fuel in the gasoline boiling range and an amount, sufficient to prevent or to reduce the formation of intake valve deposits, of
(A) an amino phenol of the general formula
wherein each A is independently H or a hydrocarbyl group, each T is independently H or a hydrocarbyl group of up to
28 carbon atoms, a, b and c are each independently an integer of at least one with the proviso that the sum of a, b and c does not exceed the unsatisfied valences of Ar; and Ar is a single ring, a fused polynuclear ring or a linked polynuclear ring aromatic moiety, having 0 to 3 optional substituents selected from
lower alkyl, lower alkoxyl, nitro, carboxy lower alkyl, nitroso, halo and combinations of two or more of said optional substituents; and

(B) an amine of the general formula
wherein R¹ is a hydrocarbyl group containing from 8 to 24 carbon atoms, R² and R³ are each independently H, a hydrocarbyl group containing from 1 to 24 carbon atoms or a group of the general formula
wherein R⁵ is an alkylene group containing from 2 to 8 carbon atoms, and R² and R³ are as defined hereinabove, each R⁴ is independently an alkylene group containing from 2 to 8 carbon atoms, and each of x, y and z is independently an integer from 0 to 20;
with the proviso that the composition does not contain an alkyl phenol;
comprising adding (A) and (B) to the fuel.
A process as claimed in claim 1 or claim 2 wherein each A is independently H or an alkyl or alkenyl group containing up to 18 carbon atoms.
A process as claimed in claim 1 or claim 2 wherein at least one A is a hydrocarbyl group having an average of from 9 up to 750 aliphatic carbon atoms.
A process as claimed in claim 4 wherein the hydrocarbyl group A is an alkyl or alkenyl group containing from 30 to 400 carbon atoms and which is made from homopolymerized or interpolymerized C₂₋₁₀ olefins.
The process of claim 1 or claim 2 wherein there are no optional substituents on Ar, b and c are each 1 and one A is a hydrocarbyl group.
The process of any preceding claim wherein each T is independently H or an alkyl or alkenyl group.
The process of claim 1 or claim 2 wherein the amino phenol (A) is of the general formula
wherein R' is a substantially saturated hydrocarbon-based group having an average of from 30 to 400 aliphatic carbon atoms; R'' is a member selected from
lower alkyl, lower alkoxyl, carboxy lower alkyl, nitro, nitroso and halo; and p is 0 or 1.
The process of any preceding claim wherein the hydrocarbyl group R¹ is an alkyl or alkenyl group.
The process of any preceding claim wherein y and z are both zero.
The process of any one of claims 1 to 9 wherein x is 0 and at least one of y and z is an integer from 1 to 5.
The process of any one of claims 1 to 11 wherein the weight ratio of (A) to (B) is in the range of from 150:1 to 1:100.
The process of any one of claims 1 to 12 wherein the composition comprises from 10 to 150 pounds by weight, per thousand barrels (0.0285-0.4281 kg/m³) of fuel, of (A) and from 1 to 100 pounds by weight per thousand barrels (0.0029-0.2854 kg/m³) of fuel, of (B).
The process of any one of claims 1-13 wherein the composition further comprises (C) a fluidizer oil.
The process of claim 14 wherein the composition comprises (C) the fluidizer oil in the weight ratio of (A):(C) in the range of from 1:20 to 3:1.
The composition of claim 14 wherein the composition comprises from 30 to 150 pounds by weight per thousand barrels (0.0856-0.4289 kg/m³) of fuel of (C) the fluidizer oil.
A method for providing total intake system cleanliness in a gasoline fueled, internal combustion engine, which method comprises fueling said engine with the motor fuel composition prepared according to the process of claim 1.
A method for preventing or reducing the formation of intake valve deposits in a port fuel injected, gasoline fueled, internal combustion engine, or for removing such deposits where they have formed, which comprises fueling said engine with the motor fuel composition prepared according to the process of claim 2.
A method for cleaning a dirty fuel delivery system for a gasoline fueled internal combustion engine, which system comprises port fuel injectors and intake valves, which method comprises operating an internal combustion engine with a fuel comprising a normally liquid fuel in the gasoline boiling range; from 200 to 1000 pounds by weight per thousand barrels (0.5708-2.8540 kg/m³) of fuel of
(A) an amino phenol of the formula
wherein each A is independently H or a substantially saturated hydrocarbon-based group, each T is independently H or a hydrocarbyl group of up to 28 carbon atoms, a, b and c are each independently an integer of at least one with the proviso that the sum of a, b and c does not exceed the unsatisfied valences of Ar; and Ar is a single ring, a fused polynuclear ring or a linked polynuclear ring aromatic moiety having 0 to 3 optional substituents selected from
alkyl, lower alkoxyl, nitro, carboxy lower alkyl, nitroso, halo and combinations of two or more of said optional from 20 to 100 pounds by weight per thousand barrels (0.0571-0.2854 kg/m³) of fuel of

(B) an amine of the general formula
wherein R¹ is a hydrocarbyl group containing from 8 to 24 carbon atoms, R² and R³ are each independently H, a hydrocarbyl group containing from 1 to 24 carbon atoms or a group of the general formula
wherein R⁵ is an alkylene group containing from 2 to 8 carbon atoms, and R² and R³ are as defined hereinabove, each R⁴ is independently an alkylene group containing from 2 to 8 carbon atoms, and each of x, y and z is independently an integer from 0 to 20;
with the proviso that the composition does not contain an alkyl phenol.
The method of claim 19 wherein the fuel also comprises from 200 to 1000 pounds by weight per thousand barrels (0.5708-2.8540 kg/m³) of fuel of
(C) a fluidizer oil.