GB2361011A

GB2361011A - Composition

Info

Publication number: GB2361011A
Application number: GB0008118A
Authority: GB
Inventors: Matthew Vincent; Simon Mulqueen
Original assignee: Associated Octel Co Ltd
Current assignee: Innospec Ltd
Priority date: 2000-04-03
Filing date: 2000-04-03
Publication date: 2001-10-10
Also published as: GB0008118D0

Abstract

There is provided use of a composition for the prevention and/or inhibition of valve seat recession of an internal combustion engine, the composition comprising phosphorus and/or a phosphorus compound; and manganese and/or a manganese compound.

Description

COMPOSITION The present invention relates to a composition. In particular, the present invention relates to a fuel additive composition.

All references in the present specification to Valvemaster may be read to mean phosphorus and/or a phosphorus containing compound and/or an amine salt of a phosphorus based acid and/or the reaction product of the following reaction C,3 alcohol + P205--> organic acid organic acid + amine -> amine sale of a phosphorus based acid and/or a product described in US-A-4720288.

The manganese compounds 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 compounds. For best results, use should be made of a cyclopentadienyl manganese tricarbonyl compound of the type described in U.S. Pat. Nos. 2,828,417 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, trimethylcyclopentadienyl manganese tricarbonyl, propylcyclopentadienyl manganese tricarbonyl, isopropylcyclopentadienyl manganese tricarbonyl, butyl cyclopentad ienyl manganese tricarbonyl, pentylcyclopentadienyl manganese tricarbonyl, hexylcyclopentadienyl manganese tricarbonyl, ethyl methylcyclopentadienyl manganese tricarbonyl, dimethyloctylcyclopentad ienyl 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 practice of this invention is methyl cyclopentad ienyl manganese tricarbonyl.

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 organomanganese compounds which may be employed include the non-ionic diamine manganese tricarbonyl halide compounds such as bromo manganese tricarbonyl halide compounds such as bromo manganese dianiline tricarbonyl and bromo manganese dipyridine tricarbonyl, described in U.S.Pat. No. 2,902489; the acyl manganese tricarbonyls such as methylacetyl cyclopentadienyl manganese tricarbonyl and benzoyl methyl cyclopentadienyl 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. 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)2L, 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, S02, tetra hydrofuran, or the like. Such compounds are referred to, for example in, Herberhold, M., Metal 7u- 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.

VSR is an abbreviation of valve seat recession. In this context it generally means valve seat recession of an internal combustion engine, such as a petroi/gasoline internal combustion engine.

The mechanism for VSR protection from the phosphorus additive, ValvemasterTM lies in the formation of P205 in the engine. Deposits are laid down between the exhaust valve and its seat, preventing metal to metal contact, which leads to valve seat recession. The product combustion of methyl cyclopentadienyl manganese tricarbonyi is manganese oxide, which is a slightly abrasive material not expected to provide significant VSR protection. However the combination of methyl cyclopentadienyl manganese tricarbonyl, which is an octane enhancing additive, added to the Valvemaster to provide a combined VSR and octane boosting additive formulation, has demonstrated a clear unexpected additional VSR benefit. The probable explanation for this unexpected benefit lies in the formation of reaction products of manganese and phosphorus which provide enhanced VSR protection. We anticipate that this would be of benefit in commercial formulations of Valvemaster and methyl cyclopentadienyl manganese tricarbonyl, where Valvemaster additions as low as 10mglkg in combination with methyl cyclopentadienyl manganese tricarbonyl 20mg/kg to 100 mg/kg would allow simultaneous octane enhancement and VSR protection of a high level. Normally, 30mglkg of phosphorus (600mglkg ValvemasterTM) are added to provide a high level of VSR protection regarded as satisfactory for vulnerable cast iron engines. This level is supported by significant field experience. VSR Test Procedure - Octel Cycle 3 (Motorway) Testing was completed using an Austin Maestro vehicle with a 1.3 litre Rover A Series engine. Technical details of this engine which is know to be prone to VSR are summarised below:

Type Rover `A' series Capacity, cc 1275 No of cylinders 4 Valve operation OHV Bore, mm 70.6 Stroke, mm 81.3 Compression ratio 9.75:1 Fuel system Carburettor Type SU HIF 44 Prior to use the engine cylinder head was stripped and cleaned. New valves were fitted and the cylinder head rebuilt with original valve springs. The heights of each assembled valve stem was measured. The head was refitted. Ignition timing and CO emissions of the engine were set to manufacturers specification, compression pressures measured and valve clearances set to 0.33mm. The vehicle was fitted to a Labeco chassis dynamometer and programmed to run the following 4`" gear test cycle: # 100 kph for 10 minutes # 120 kph for 20 minutes # 80 kph for 10 minutes # 120 kph for 20 minutes Valve clearances were measured every 4 hours and any reduction in clearances were restored and the measurements recorded. The design duration of the test was 5000 km or a reduction in valve clearance of about 0.13mm. Restriction on allowed reduction in valve clearance eliminates the potential for excessive valve seat sinkage and allows a common head to be used for several evaluation. At the end of test the cylinder head was again removed and assembled valve stem heights measured. The differences between start and end of test were recorded and represent the level of valve seat recession.

VSR test results Test 1 - Unleaded gasoline containing 600 mg/kg Valvemaster (30 mg/kg phosphorus) Test duration - 5000 kms Measured valve height differences of most recessed cylinder - ca -0.01 Test 2 - Unleaded gasoline containing 50 mg/kg methyl cyclopentadienyl manganese tricarbonyl Test duration - < 5000 km Measured valve height difference of most recessed cylinder - ca -0.12mm Test 3 - Unleaded gasoline containing 200 mg/kg Valvemaster (10 mg/kg phosphorus) Test duration - < 5000 km Measured valve height difference of most recessed cylinder - ca -0.13mm Test 4 - Unleaded gasoline containing 200 mg/kg Valvemaster (10 mglkg phosphorus) and 50 mg/kg methyl cyclopentadienyl manganese tricarbonyl.

Test duration - 5000 km Measured valve height difference of most recessed cylinder - ca -0.01 mm.

All publications mentioned in the above specification are herein incorporated by reference. Various modifications and variations of the described methods and system of the invention will be apparent to those skilled in the art without departing from the scope and spirit of the invention. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in chemistry or related fields are intended tc. :a within the scope of the following claims.

Claims

CLAIMS 1. Use of a composition for the prevention and/or inhibition of valve seat recession of an internal combustion engine, the composition comprising phosphorus and/or a phosphorus compound; and manganese and/or a manganese compound.
2. A fuel additive composition comprising (i) phosphorus and/or a phosphorus compound; and (ii) manganese and/or a manganese compound
3. A fuel composition comprising (i) phosphorus and/or a phosphorus compound (ii) manganese and/or a manganese compound; and (iii) a fuel.
4. The invention of any one of the preceding claims wherein the phosphorus compound is an amine salt of a phosphorus based acid.
5. The invention of any one of the preceding claims wherein the manganese compound is manganese complex selected from cyclopentadienyl manganese tricarbonyl and substituted- cyclopentadienyl manganese tricarbonyl.
6. The invention of any one of the preceding claims wherein the manganese compound is methyl cyclopentadienyl manganese tricarbonyl.
7. The invention of any one of the preceding claims wherein the phosphorus and/or the phosphorus compound provides elemental phosphorus in an amount of at least 10mg per kg of fuel.
8. The invention of any one of the preceding claims wherein the phosphorus and/or the phosphorus compound provides elemental phosphorus in an amount of from 10 to 20 mg per kg of fuel.
9. The invention of any one of claims 1 to 6 wherein the phosphorus and/or the phosphorus compound provides elemental phosphorus in an amount of from
10 to 40 mg per kg of fuel. 10. The invention of any one of claims 1 to 6 wherein the phosphorus and/or the phosphorus compound provides elemental phosphorus in an amount of from 25 to 35 mg per kg of fuel.
11. The invention of any one of the preceding claims wherein the manganese and/or the manganese compound provides elemental manganese in an amount of at least 5 mg per kg of fuel.
12. The invention of any one of claims 1 to 9 wherein the manganese and/or the manganese compound provides elemental manganese in an amount of at least 30 mg per kg of fuel.
13. The invention of any one of claims 1 to 10 wherein the manganese and/or the manganese compound provides elemental manganese in an amount from 7 to
14 mg per kg of fuel. 14. Use as substantially defined herein with reference to any one of the Examples.
15. A fuel additive as substantially defined herein with reference to any one of the Examples.
16. A fuel composition as substantially defined herein with reference to any one of the Examples