Mineral oils: processes and products – Products and compositions – Fuels
Reexamination Certificate
2000-06-07
2002-04-30
Dang, Thuan D. (Department: 1764)
Mineral oils: processes and products
Products and compositions
Fuels
C208S016000, C208S017000, C548S314700
Reexamination Certificate
active
06379530
ABSTRACT:
TECHNICAL FIELD
This invention relates to novel polyisobutene substituted succinimides and their use as fuel additives.
BACKGROUND OF THE INVENTION
Hydrocarbon fuels generally contain numerous deposit-forming substances. When used in internal combustion engines, deposits tend to form on and around constricted areas of the engine in contact with the fuel. In diesel engines, deposits tend to accumulate in the fuel injection system, thereby hampering good performance of the engine. In spark ignition engines deposits can build up on engine intake valves leading to progressive restriction of gaseous fuel mixture flow into the combustion chamber and also to valve sticking. It is common practice therefore to incorporate a detergent in the fuel composition for the purpose of inhibiting the formation, and facilitating the removal, of engine deposits, thereby improving engine performance.
Many different types of compounds are known as detergents for fuels. Typical examples include polyisobutene-substituted (PiB) succinimides such as those disclosed in EP-A-565285, where the amine portion is derived from a polyalkylene amine.
JP-A-07278142 discloses that the reaction product of an imidazoline and a PiB succinic acid is useful as a dispersant in compositions which are used as lubricants for gasoline.
It has now been discovered the novel PiB succinimides of this invention are effective detergents for use in fuels.
SUMMARY OF THE INVENTION
This invention relates to a compound represented by the formula
wherein in formula (I): R is a polyisobutene group; R
1
, R
2
and R
3
are each independently hydrogen, alkyl groups of 1 to 18 carbon atoms, cycloalkyl groups of 4 to 10 carbon atoms or aryl groups of 6 to 10 carbon atoms; and n is an integer of 0 to 4. The invention also relates to an additive package for use in making fuels comprising the foregoing compound. The invention relates to fuel compositions containing the foregoing compound.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The novel compounds of the invention are compounds represented by the formula
wherein in formula (I): R is a polyisobutene (PiB) group; R
1
, R
2
and R
3
are each independently hydrogen alkyl groups of 1 to 18 carbon atoms, cycloalkyl groups of 4 to 10 carbon atoms, or aryl groups of 6 to 10 carbon atoms; and n is an integer of from 0 to 4. In one embodiment, R
1
, R
2
and R
3
are each H. In one embodiment, n is 1 to 4, and in one embodiment n is 3.
In one embodiment, the polyisobutene group R is derived from a “high reactive” PiB. PiBs in which at least 70% of the terminal olefinic double bonds are of the vinylidene type are commonly known as “high reactive” polyisobutenes, as distinguished from “low reactive” PiBs having a lower proportion of vinylidene terminal double bonds. In one embodiment, at least 80% of the terminal olefinic double bonds are of the vinylidene type, and in one embodiment at least 90% are of the vinylidene type. Examples of “high reactive” polyisobutenes include Ultravis® marketed by BP Chemicals and Glissopal® marketed by BASF.
Preferably the PiB has a number average molecular weight of from 700 to 2500, and in one embodiment from 750 to 1500.
In one embodiment, the compounds of the invention may be made by reacting a PiB-substituted succinic acylating agent such a polyisobutene succinic anhydride (PiBSA) with aminopropylimidazole. Methods for making PiB-substituted succinic acylating agents are well known in the art; examples are disclosed in EP-A-565285 and EP-A-623631. In one embodiment, the compounds are made by reacting the acylating agent with aminopropylimidazole in the presence of a solvent. The solvent can be an aromatic or aliphatic hydrocarbon solvent.
In one embodiment, the invention provides for a fuel composition comprising a major amount of a hydrocarbon fuel, and from 10 to 1000 parts per million (ppm) based on the total weight of the fuel composition of foregoing compound of the invention. In one embodiment, the compound of the invention is added to the fuel as part of an additive package, the package being added to the fuel at concentrations of from 200 to 3000 ppm, and in one embodiment from 600 to 1000 ppm. Thus another aspect of the invention provides an additive package for fuel compositions, comprising from 5 to 30% by weight of the inventive compound, a carrier fluid, and optionally a solvent, preferably an aromatic or aliphatic hydrocarbon solvent. Suitable carrier fluids include alkyl phenols, optionally alkoxylated; esters of acids/alcohols, acids/polyols or acids/glycol ethers, the acids being saturated or unsaturated; phthalate esters; trimellitate esters; alkoxylated alcohols or polyols; polyalkylene glycols; and lubricating oils. Suitable solvents may include most known aromatic or aliphatic hydrocarbons or glycol ethers. The invention also comprises in a still further aspect the use of the inventive compounds or additive packages as detergents in hydrocarbon fuels.
In one embodiment, the hydrocarbon fuel comprises a hydrocarbon fraction boiling in the gasoline range or a hydrocarbon fraction boiling in the diesel range. Gasolines suitable for use in spark ignition or gasoline engines, e.g. automobile engines, generally boil in the range from 30° C. to 230° C. Such gasolines may comprise mixtures of saturated, olefinic and aromatic hydrocarbons. They may be derived from straight-run gasoline, synthetically produced aromatic hydrocarbon mixtures, thermally or catalytically cracked hydrocarbon feedstocks, hydrocracked petroleum fractions or catalytically reformed hydrocarbons. The octane number of the base fuel is not critical and will generally be above 65. In the gasoline, hydrocarbons may be replaced in part by alcohols, ethers, ketones or esters, typically in an amount up to 20% by weight. Alternatively, as the liquid hydrocarbon fuel there may be used any fuel suitable for operating spark compression or diesel engines, such as those which may be found in road vehicles, ships and the like. Generally, such a diesel fuel will boil in the range from about 140° C. to about 400° C. (at atmospheric pressure), particularly in the range from about 150° C. to 390° C., especially from about 175° C. to 370° C. Such fuels may be obtained directly from crude oil (straight-run) or from a catalytically or thermally cracked product or a hydrotreated product, or from a mixture of the aforesaid. Alternatively there may be used a biofuel, for example rape seed methyl ester. The cetane number will typically be in the range from 25 to 60.
In one embodiment, the fuel composition contains the compound of formula (I) in an amount sufficient to provide dispersancy. Typically in a gasoline fuel this amount is in the range from 20 to 1000 ppm w/w based on the total weight of the composition. Typically in a diesel fuel this amount is in the range from 10 to 500 ppm w/w based on the total weight of the composition.
The fuel composition may be prepared by blending a concentrate composition comprising a fuel compatible hydrocarbon solvent and the compound of formula (I) with the hydrocarbon fuel.
The fuel composition may contain in addition to the compound of formula (I) known fuel additives. The nature of the additives depend to some extent on the end-use of the fuel composition. Diesel fuel compositions may contain nitrates or nitrites as a cetane improvers, or copolymers of ethylene and/or vinylesters, e.g. vinylacetate, as pour point depressants. Gasoline fuel compositions may contain a lead compound as an anti-knock additive and/or an antioxidant, e.g. 2,6-di-tert-butyl phenol, and/or an anti-knock compound other than a lead compound, and/or an additional dispersant, for example a PIB polyamine. The other additives (if any) may be blended directly into the fuel composition or may be incorporated by way of a concentrate composition.
The compounds of the invention are useful as thermal stabilisers for jet fuels. In high speed aircraft, both civilian and military, the liquid fuel is combusted to produce power, but also is circulated in the aircraft as a heat exchange fluid to remove
Dang Thuan D.
Esposito Michael F.
Laferty Samuel B.
Shold David M.
The Lubrizol Corporation
LandOfFree
Polyisobutene substituted succinimides does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Polyisobutene substituted succinimides, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Polyisobutene substituted succinimides will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2866537