Additive concentrate for use with gasolines

Details Additive concentrate for use with gasolines Additive concentrate for use with gasolines

1996-08-26

1998-02-24

McAvoy, Ellen M.

Fuel and related compositions

Liquid fuels

C10L 114, C10L 116

Patent

active

057207828

DESCRIPTION:

BRIEF SUMMARY
The present invention relates to an additive concentrate for use with gasoline, used in gasoline-fuelled engines.
Certain chemicals, termed "additives" are included in gasoline to enhance its properties, combustion characteristics and the resulting combustion products.
Some additives cannot be directly incorporated into gasoline. They may not be readily soluble or dispersible in gasoline. They may also be less effective or have an adverse effect on engine components during use of the gasoline. For example, some additives may leave a sticky residue on intake valves. Accordingly, such additives may be dissolved and/or dispersed in a carrier fluid to form an additive concentrate, and the concentrate is added to or blended with the gasoline. A common carrier fluid is a mineral oil fraction such as a neutral lubricating oil basestock, e.g. S600N.
Carrier fluids can also have an adverse effect on the properties of gasolines into which they are blended. For example, they can increase the amount of combustion chamber deposits in an engine.
It has now been found, in accordance with the discovery forming the basis of this invention, that a hydrocarbon liquid made by the isomerisation of wax can act as a carrier fluid for additives which is less subject to the problems and/or drawbacks of previous types of carrier fluids.
It is known, e.g. from GB-A-1,538,578 to use waxy materials which may include wax isomerates as components of pour point depressant additive combinations in diesel fuels and heating oils. Pour point depressants are not normally added to gasolines.
In one aspect, the invention provides an additive concentrate comprising at least one additive for gasoline dispersed and/or dissolved in a hydrocarbon carrier fluid of which at least a component is a wax isomerate made by the isomerising of wax in the presence of a wax isomerisation catalyst.
In another aspect, the invention provides a novel use of a hydrocarbon liquid made by the isomerisation of wax, wherein the said hydrocarbon liquid is employed as a carrier fluid for at least one additive used or useful in gasoline.
It has been found that hydrocarbon liquid obtained by wax isomerisation serves as an effective carrier fluid for gasoline additives, and does not produce as much deposit in the combustion chambers of gasoline engines as previous carrier fluids.
Preferably, the isomerised wax hydrocarbon liquid, herein referred to as "wax isomerate" or "isomerate" for brevity, has a viscosity at 100.degree. C. in the range of from 4 to 12, more preferably 4 to 8 mm.sup.2 /s (cSt) , for example, about 6 mm.sup.2 /s, and a viscosity index (VI) in the range of from 120 to 150, e.g. from 135 to 145.
The isomerate may have been made by the isomerisation of slack wax, and the slack wax may contain up to 15 w % oil, e.g. up to 12 w % oil. The conversion in the wax isomerisation step may be less than 25%, e.g. no more than 20%. The slack wax and/or the isomerate may have been hydrofined to reduce its content of heteroatoms (e.g. oxygen, nitrogen, sulphur) to very low levels.
The wax isomerisation is effected in the presence of a wax isomerisation catalyst, and may be effected in the presence of hydrogen. A suitable catalyst is a Group 8 metal (e.g., a noble metal such as platinum) dispersed on a refractory oxide support (e.g. alumina). The catalyst may contain halogen (e.g. fluorine), associated with the metal and/or the support. A suitable catalyst is platinum dispersed on fluorinated alumina. The catalyst is preferably in the form of particles, preferably having sizes predominantly in the range of from 0.4 to 0.8 mm. The particles may be pre-formed in this size range or formed in a larger size range and crushed and sieved.
Processes for making wax isomerates suitable for use as carrier fluids for gasoline-additives are described in US patents U.S. Pat. No. 4,937,399 and U.S. Pat. No. 5,059,299.
The additive concentrate may comprise a detergent to reduce the incidence of deposit formation in the intake system of a gasoline engine. The detergent may comprise a pol

REFERENCES:
patent: 2904493 (1959-09-01), Hartzband
patent: 3877887 (1975-04-01), Moore et al.
patent: 4022589 (1977-05-01), Alquist et al.
patent: 4155718 (1979-05-01), Graiff
patent: 4515740 (1985-05-01), Schuettenberg et al.
patent: 4639255 (1987-01-01), Schuettenberg et al.
patent: 4929795 (1990-05-01), Cody et al.
patent: 4937399 (1990-06-01), Wachter et al.
patent: 5059299 (1991-10-01), Cody et al.
patent: 5149452 (1992-09-01), MacAlpine et al.
patent: 5229021 (1993-07-01), Pillon et al.
patent: 5352374 (1994-10-01), Habeeb et al.
patent: 5466364 (1995-11-01), Kaul et al.
patent: 5558807 (1996-09-01), Kim
PCT/GB94/01972, International Search Report, Exxon Research & Engineering Co., Jan. 1995.
PCT/GB94/01972, International Preliminary Examination Report, Exxon Research & Eng. Co., Oct. 1995.

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