Polymeric additives

Details Polymeric additives Polymeric additives

1993-08-27

1995-10-10

Howard, Jacqueline V.

Fuel and related compositions

Liquid fuels

Containing acyclic oxygen single bonded to acyclic oxygen

44324, 44386, 44412, 44451, C10L 118, C10L 122, C08F 830

Patent

active

054567300

DESCRIPTION:

BRIEF SUMMARY
This invention relates to oil-soluble polymers and their use in oils as flow improvers or in middle distillate fuels as cetane improvers.
Cetane improvers are additives used to raise the cetane number of fuel. Many types of additive have been proposed and used to raise the octane number of Diesel fuel, examples of which include peroxides, nitrites, nitrates and nitrosocarbonates. Alkyl nitrates such as amyl nitrate, hexyl nitrate and mixed octyl nitrates have been used commercially for this purpose. The following patent specifications describe the use of nitrates for improving the cetane number of Diesel fuel: U.S. Pat. No. 4,420,311 and U.S. Pat. No. 4,406,665.
Flow improvers are additives used to improve the flow characteristics of middle distillate fuels at decreased temperatures where the fuels lose fluidity due to crystallisation of wax in the fuel into plate-like crystals that eventually form a spongy mass that entraps the fuel. The additives work by modifying the size of the wax crystals and reduce the adhesive forces between the wax and fuel in such a way as to improve the filterability of the fuel and permit it to remain fluid at a lower temperature. They are also known in the art. Examples include polymers that have a polymethylene backbone which is divided into segments by hydrocarbon or oxy-hydrocarbon side chains, by aliphatic or heterocyclic structures or by chlorine. Such polymers are described, for example in U.S. Pat. Nos. 3,048,479; 3,961,916 and 4,261,703.
It has now been found according to this invention that certain polymers can function both as cetane improvers and flow improvers in fuel oils and as flow improvers in lubricating oil and crude oil.
Thus, this invention, in a first aspect, is a composition comprising a major proportion of a fuel oil, lubricating oil or crude oil and a minor proportion of an additive comprising an oil-soluble polymer of number average molecular weight in the range of 200 to 50,000, the polymer having or including a polymer backbone carrying a plurality of the same or different functional groups that give rise to cetane improving properties in a fuel oil when the polymer is an additive therefor.
In another aspect, the invention is the use of the polymer of the first aspect of the invention as a cetane improver in a middle distillate fuel or as flow improver in a fuel oil, lubricating oil or crude oil.
In another aspect, the invention is a concentrate for adding to a fuel oil, lubricating oil or crude oil comprising the polymer of the first aspect of the invention in admixture with a liquid carrier therefor.
In another aspect, the invention is a method of operating a diesel engine which includes introducing to the engine as the fuel a composition comprising a major proportion of a middle distillate fuel and a minor proportion of a polymer of the first aspect of the invention.
In another aspect, the invention is an oil-soluble polymer of number average molecular weight in the range of 200 to 50,000 having or including a polymethylene backbone carrying a plurality of the same or different functional groups that give rise to cetane improving properties in a fuel oil when the polymer is an additive therefor, and groups of the formula R--CO--O-- where R is a hydrocarbyl group having 1 to 28 carbon atoms.
The features of the invention will now be described in more detail as follows.


POLYMER

The polymer may, for example, be a homopolymer or a copolymer, where it may be a block copolymer or a random copolymer. The defined backbone according to this invention may constitute part only of the overall polymer backbone or may constitute substantially all of the polymer backbone. A preferred example of defined backbone is a polymethylene backbone which may optionally be interrupted by one or more hetero atoms such as oxygen or a group or groups containing one or more hetero atoms.
Examples of the functional groups are nitrate, peroxide, nitrite or nitrosocarbonate, such groups being precursor groups that initiate combustion in a fuel by generation of free radicals. N

REFERENCES:
patent: 2378466 (1945-06-01), Curme, Jr.
patent: 3048479 (1962-08-01), Ilnyckyj et al.
patent: 3410671 (1968-11-01), Le Suer
patent: 3449437 (1969-06-01), Lee
patent: 3846092 (1974-11-01), Pappas et al.
patent: 3861916 (1975-01-01), Logue
patent: 3961916 (1976-06-01), Ilnyckyj et al.
patent: 4261703 (1981-04-01), Tack et al.
patent: 4406665 (1983-09-01), Filbey
patent: 4420311 (1983-12-01), Thomas
patent: 4491455 (1985-01-01), Ishizaki et al.
patent: 4631071 (1986-12-01), Axelrod et al.
patent: 4639256 (1987-01-01), Axelrod et al.
"New Laboratory Test for Predicting Low-temperature Operability of Diesel Fuels" Journal of the Institute of Petroleum, T. Coley, L. F. Rutishauser, and H. M. Ashton vol. 52, No. 510-Jun. 1966, pp. 173-185.

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