US3718444A

US3718444A - Jet fuel additive

Info

Publication number: US3718444A
Application number: US00785800A
Authority: US
Inventors: V Hnizda
Original assignee: Ethyl Corp
Current assignee: Ethyl Corp
Priority date: 1968-12-20
Filing date: 1968-12-20
Publication date: 1973-02-27
Anticipated expiration: 1990-02-27

Abstract

A method of reducing manganese containing deposits formed on the surfaces of jet engines from burning fuel containing organomanganese compounds as a smoke reducer is described. The deposits are reduced by adding an organic molybdenum compound to the organomanganese containing fuel. Cyclopentadienyl manganese tricarbonyl compounds are useful organomanganese compounds; molybdenum naphthenate is a useful molybdenum compound.

Description

mted States Patent m1 0 1 3,718,444

Hnizda [451 Feb. 27, 1973 [5 1 JET FUEL ADDITIVE 3,153,901 10/1964 R100 ..44/68 3,402,188 9 1968 W' ...44 68 [751 Invenm" F Hmzd! 3,446,735 5i1969 .;...44i6s Woods, Mich. 73 Assignee: Ethyl CorporationQNew'York, NY. Primary Examiner-139M915 y 1 Assistant Examiner-Mrs. Y. H. Smit [22] Ffled: 1968 AttorneyD0na1d L. Johnson [21] Appl. No.: 785,800

- [57] ABSTRACT 52 us. (:1 ..44/66, 44/68 A method of reducing manganese containing deposits 51 1111.01. ..C10l1/26 form on the Surfaces of jet engines from burning 58 Field at Search ..44/57, 66, 68 fuel containing organomaflgamese as a smoke reducer is described. The deposits are reduced [56] References Cited by adding an organic molybdenum compound to the organomanganese containing fuel.

. UNITED STATES PATENTS Cyclopentadienyl manganese tricarbonyl compounds 2,737,932 3/1956 Thomas ..44/68 UX are useful organomanganese compounds; molyb- 2,88l,062 4/1959 Bisho ..44/68 denum naphthenate is a useful molybdenum com- 3,003,ss9 10/1961 Irish etal ..44/68 pound 3,109,010 10/1963 Wilkinson ..44/68 3,112,789 Percy et al.... ..44/68 14 Claims, No Drawings JET FUEL ADDITIVE BACKGROUND OF THE INVENTION of useful compounds of this type, and includes methods of preparing them. Although use of these manganese additives substantially reduces the exhaust smoke, a secondary problem may arise in some instances. On

combustion of the fuel containing the manganese compound, manganese containing deposits are formed on the engine surface which was contacted by the exhaust products. As with many engine deposits, an effective method of reducing these manganese containing deposits is desirable.

SUMMARY OF THE INVENTION A method of reducing manganese containing deposits formed on the surfaces of jet engines which burn fuel containing organomanganese compounds, which comprises adding to said fuel prior to burning, a deposit reducing amount of an organic molybdenum compound; jet fuels containing an organomanganese compound and a deposit reducing amount of an organic molybdenum compound.

DESCRIPTION OF PREFERRED EMBODIMENT An embodiment of this invention is a method of reducing manganese containing deposits formed on the surface of a jet engine from burning a fuel containing a smoke reducing quantity of a cyclopentadienyl manganese tricarbonyl, wherein the cyclopentadienyl radical has up to 17 carbon atoms; which comprises adding to said fuel prior to burning, a deposit reducing amount of a suitable molybdenum compound. 'A preferred embodiment involves use as a deposit reducer of an organic molybdenum compound selected from the group consisting of 1. molybdenum chelates and 2. molybdenum'salts of I a. phenol and c,-c,, alkyl substitutedphenols b. phosphoricacids having the formula XI I{1X'-'-" wherein X, X, X and X are independently selected from O and S and R and R are independently selected from hydrocarbon alkyl and aryl groups having from I to about 30 carbon atoms c. hydrocarbon carboxylic acids having from five to about 24 carbon atoms, and

d. naphthenicacids. Fuel compositions which are used in the preferred method contain 0.025 to about 6.45 grams of manganese per gallon as a cyclopentadienyl manganese tricarbonyl and sufficient organic molybdenum compound so that the atomic ratio of manganese (Mn): molybdenum (M0) is from about 5:1 to about 1:2. A ratio of MnzMo of about 1:1 to 4:1 is preferred. Molybdenum dialkylphosphorodithioates or molybdenum naphthenate and (methylcyclopentadienyl)manganese tricarbonyl in the preferred ratio in the fuel are most preferred embodiments.

Manganese compounds which are useful as smoke reducers in jet fuels are cyclopentadienyl manganese tricarbonyls having the formula RMn(CO), wherein R is a cyclopentadienyl hydrocarbon radical having from five to 17 carbon atoms. U. S. Pat. No. 2,8l8,4l7, issued Dec. 31, 1957, contains an extensive disclosure of the type of manganese compounds which are useful. This listing of compounds is incorporated by reference.

(Methylcyclopentadienyl)manganese tricarbonyl is an especially effective smoke reducer.

The concentration of the manganese tricarbonyl in the jet fuels may be varied. Concentrations from 0.025 to about 6.45 grams of manganese per gallon as a cyclopentadienyl manganese tricarbonyl are useful.

By jet fuels, we include distillate hydrocarbons and blends which are useful as fuel for jet engines. These fuels are principally hydrocarbon distillates heavier than gasoline. In other words, they are distillate hydrocarbon fuels having a higher end point than gasoline. They are generally composed of distillate fuels and naphthas and blends of the above, including blends with lighter hydrocarbon fractions. The end point of preferable jet fuels is at least 435F..and more preferably greater than 470F.

Typical jet fuels include JP-3, a mixture of about 70 per cent gasoline and 30 per cent light distillate having a 90 per cent evaporation point of 470F.; JP-4, a mixture of about 65 per cent gasoline and 35 per cent light distillate especially designed for high altitude performance; JP-S, an especially fractionated kerosene and the like.

Molybdenum compounds which are useful in the present invention are organic, oil soluble or oil dispersible compounds. They include molybdenum salts, chelates, complex compounds and the like. Organic molybdenum compounds which are oil soluble are preferred;by oil soluble is meant sufficient solubility in jet fuel to effect deposit reduction as herein described.

One class of useful organic molybdenum compounds are molybdenum chelates. These chelates are coordination compounds in which a central molybdenum atom is joined to two or more atoms of one or more other molecules or ions (called ligands) so that one or more heterocyclic rings are formed with the central molybdenum atom as part of each ring. Examples of these compounds are chelate complexes of molybdenum with acetylacetone, N-nitrosophenylhydroxylamine, dimethylglyoxime, ethylenediamine, ethylenediaminetetraacetic acid, nitrilotriacetic acid, 8-hydroxyquinoline, benzoylacetone and similar chelating agents.

Another class of useful organic compounds are the molybdenum phenates. These are salts of molybdenum and phenol or substituted phenols, and especially C alkylphenols. The simplest member of this class of compounds is molybdenum phenate; representative formula for molybdenum phenates are Mo(OPh and wherein x is an integer from 2-6 inclusive and Ph is the phenyl or substituted phenyl group. Salts of molybdenum and the following phenols are useful 4-methylphenol 4-octadecylphenol 4-oleylphenol 4-(2-ethyl-n-hexyl)phenol 2,6-dimethylphenol 2,4,6-trimethylphenol o-chlorophenol 2-dodecylphenol 2,4-dododecylphenol 4-nonylphenol Z-tert-butylphenol 3-nitrophenol and the like.

An especially useful type of a molybdenum phenate is that derived from a commercial mixture of alkylated phenols. Commercial alkylation of phenols generally is accomplished by treating the phenol with an olefin or a mixture of olefins in the presence of an alkylating agent. This commercial alkylation ordinarily produces a mixture of various alkyl phenols. For example, if a phenol is alkylated with a C olefin, the product will contain monononylphenols, dinonylphenol, and trinonylphenol. Likewise, if a mixture of C C C olefins is used in the alkylation, a mixture of various C C and C alkylated phenols is obtained. Molybdenum salts of these commercial mixtures of alkylated phenols wherein the alkyl groups have from four to about 18 carbon atoms are also useful in the present invention.

Another class of useful compounds are molybdenum salts of hydrocarbon substituted phosphoric acids; these include the thiophosphoric acids. These phosphoric acids are represented by the following formula wherein X, X, X and X can be 0 and/or S and R and R are hydrocarbyl groups. Hydrocarbyl groups are hydrocarbon alkyl and aryl groups; hydrocarbyl groups having from one to about 30 carbon atoms are useful. Examples of molybdenum salts of acids of formula I are S-molybdenum-0,0-dimethylphosphorothioate O-molybdenum-O,O"-dioctylphosphorothioate molybdenum diphenylphosphate molybdenum diciesylphosphate S-molybdenum-O,S'-didecylphosphorodithioate molybdenum diamylphosphorotetrathioate O-molybdenum-S,S'-di-tert-butylphosphorotrithioate O-molybdenum-O,O"-dixylylphosphorothioate S-molybdenum-S',S"-di-4-ethylphenylphosphorotrithioate molybdenum diactadecylphosphorotetrathioate molybdenum cresylphenylphosphate O-molybdenum-O',O"-dinaphthylphosphorothioate S-molybdenum-O,O"-diisopropylphosphorothioate molybdenum dibenzylphosphate and the like. Salts of dithiophosphoric acids where two of X, X, X and X in Formula I are S are preferred. Examples of preferred salts are S-molybdenum-0,0'-dimethylphosphorodithioate S-molybdenum-0,0-dicresylphosphorodithioate S-molybdenum-QO'-di-4-dodecylphenylphosphorodithioate S-molybdenum-0,0'-dibenzylphosphorodithioate S-molybdenum-0,0'-dilaurylphosphorodithioate S-molybdenum-0,0'-di-2-ethylhexylphosphorodithioate S-molybdenum-0,0-diisobutylphosphorodithioate S-molybdenum-0,0'-methylphenylphosphorodithioate S-molybdenum-0,0'-dicyclohexylphosphorodithioate S-molybdenum-O,S-diamylphosphorodithioate S-molybdenum-O,S-diindenylphosphorodithioate S-molybdenum-QS-dixylylphosphorodithioate S-molybdenum-O,S-dioctadecylphosphorodithioate S-molybdenum-O,S'-diundecylphosphorodithioate O-molybdenum-S,S'-diheptylphosphorodithioate O-molybdenum-S,S'-di-2,6-tert-butylphenylphosphorodithioate O-molybdenum-S,S'-diethylphosphorodithioate O-molybdenum-S,S-ditetradecylphosphorodithioate O-molybdenum-O',S-diacetylphosphorodithioate O-molybdenum-O,S-di-2,4-didodecylphenylphosphorodithioate O-molybdenum-O,S-dioctadecylphosphorodithioate O-molybdenum-O',S-dihexylphosphorodithioate and the like.

Still another class of useful compounds are the salts of hydrocarbon carboxylic acids having from five to about 24 carbon atoms. Examples of suitable salts of this type are molybdenum pentanoate, molybdenum oleate, molybdenum linoleate, molybdenum adipate, molybdenum-2-ethylhexanoate, molybdenum benzoate, molybdenum tetradecanoate, molybdenum orthophthalate, molybdenum 4-dodecylbenzoate, molybdenum stearate, molybdenum laurate, molybdenum eicosanoate, molybdenum 4-methylpentanoate, molybdenum 4-methylbenzoate, molybdenum isovalerate, molybdenum B-napthoate, molybdenum phenylacetate, molybdenum 'y-phenylbutyrate, molybdenum o-toluate, molybdenum undecanoate, molybdenum trimethylacetate, molybdenum sebacate, molybdenum azelate, molybdenum 2,4,4-trimethylpentanoate, molybdenum 2,4,4,6,6-pentamethylheptanoate and the like.

Molybdenum salts of mixtures of fatty acids obtained from natural products such as olive oil, babassu oil, tall oil, cottonseed oil, tallow and the like are also useful. More preferred molybdenum compounds of this type are the salts of alicyclic carboxylic acids. Specific examples of useful molybdenum salts of alicyclic carboxylic acids are molybdenum cyclopentane carboxylic acid, molybdenum cyclopentylacetate, molybdenum-3- methylcyclopentylacetate, molybdenum camphonanate, molybdenum cyclohexane carboxylate, molybdenum 4-methylcyclohexanecarboxylate,

molybdenum-2,2,6-trimethylcyclohexane carboxylate and the like.

An especially preferred class of organic molybdenum salts are salts of the so-called naphthenic acids. The term naphthenic acids" is applied to a mixture of carboxylic acids obtained from the alkali washes of petroleum. These acids are complex mixtures of normal branched aliphatic acids, alkyl derivatives of cyclopentane and cyclohexane carboxylic acids and cyclopentyl and cyclohexyl derivatives of aliphatic acids. The alicyclic carboxylic acids appear to be the major constituents of these mixtures. The composition of these naphthenic acids will vary depending on factors such as the source of petroleum, the refining procedure, etc. A more detailed discussion of these naphthenic acids is presented in Chemical Technology of Petroleum," William A. Gruse and Donald R. Stevens 3rd edition, pages 6567, 1960, McGraw Hill Publishing Company; and is incorporated by reference.

For commercial use, the crude naphthenic acid mixture obtained in the alkali extract is generally refined to remove unsaponifiable material. Molybdenum salts of either the crude naphthenic acid mixture or of the refined naphthenic acid mixture are useful in the present invention. The molybdenum salts of the refined naphthenic acids are especially preferred; the term molybdenum naphthenate will be used herein to describe these especially preferred salts.

The amount of organic molybdenum compounds "described above which is added to the organomanganese containing fuel may be varied. In general, sufficient organic molybdenum compound is added to the fuel so that the atomic ratio of molybdenum (Mo):

manganese (Mn) in the fuel is about 1:5 to about 2:1. It

EXAMPLE 1 To a .lP-S (ASTM-Type A) base fuel was added 2.58 grams/gallon of Mn as (methylcyclopentadienyl)manganese tricarbonyl and 59.84 grams/gallon of a molybdenum dialkylphosphorodithioate.

The MnzMo atomic ratio of this composition is 1:1.

EXAMPLE 2 To a JP-S case fuel were added 2.5 8 grams/gallon of Mn as (methylcyclopentadienyl)manganese tricarbonyl and 29.92 grams/gallon of a molybdenum dialkylphosphorodithioate.

The MnzMo atomic ratio of this composition is 2: 1.

EXAMPLE 3 To a .lP-S base fuel were added 2.58 grams/gallon of Mn as (methylcyclopentadienyl)manganese tricarbonyl and 14.96 grams/gallon of a molybdenum dialkylphosphorodithioate.

The MnzMo atomic ratio of this composition is 4: 1.

EXAMPLE 4 To a JP-S base fuel were added 2.58 grams/gallon of Mn as (methylcyclopentadienyl)manganese tricarbonyl and 90.12 grams/gallon of a molybdenum naphthenate.

The MnzMo atomic ratio of this composition is 1:1.

EXAMPLE 5 To a JP-S base fuel were added 2.58 grams/gallon of Mn as (methylcyclopentadienyl)manganese tricarbonyl and 45.06 grams/gallon of a molybdenum naphthenate.

The MnzMo atomic ratio of this composition is 2: 1.

EXAMPLE 6 To a .lP-S base fuel were added 2.58 grams/gallon of Mn as (methylcyclopentadienyl)manganese tricarbonyl and 30.04 grams/gallon of molybdenum naphthenate.

The MnzMo atomic ratio of this composition is 3:1.

EXAMPLE 7 To a JP-5 base fuel are added 1.29 grams/gallon of Mn as (methylcyclopentadienyl)manganese tricarbonyl and 90.12 grams/gallon of a molybdenum naphthenate.

The Mn:Mo atomic ratio of this composition is 1:2.

EXAMPLE 8 To a JP-S fuel are added 5.19 grams/gallon of Mn as (methylcyclopentadienyl)manganese tricarbonyl and 36.05 grams/gallon of a molybdenum naphthenate.

The MnzMo atomic ratio of this composition is 5:1.

Useful jet fuel compositions having the deposit modifying characteristics described below are also prepared (a) by using JP-4, JP-3 and the like in place of JP-S in the above examples, (b) by using equivalent amounts of compounds such as molybdenum valerate, molybdenum chelate of B-hydroxy-quinoline, molybdenum chelate of phenylhydrazine, molybdenum chelate of acetylacetone, molydenum 2-methylphenate, molybdenum 2-methylphenate, molybdenum 4- dodecylphenate, molybdenum oleate, molybdenum 2- ethylhexanoate, molybdenum 4-isopropylbenzoate, molybdenum cyclohexanecarboxylate, S-molybdenum- S ,S -didecylphosphorotetrathioate, S-molybdenum- O,S'-dibutylphosphorotrithioate, o-molybdenum- 0',O"-diphenylphosphorothioate and the like in place of the molybdenum compounds in the above examples.

These jet fuel compositions are prepared by simply blending the required amount of manganese-containing smoke reducer and molybdenum deposit reducing compound with the base jet fuel. Conventional fuel blending apparatus and techniques are used.

When a jet fuel containing an organomanganese compound as a smoke reducer is burned in a jet engine, a manganese containing deposit is formed on parts of the engine which come in contact with the burning fuel and/or its combustion products. Quite unexpectedly, by adding a small mount of organic molybdenum compound to the fuel before burning, the amount of deposit is significantly reduced.

This unexpected deposit reducing effect was demonstrated by using the following laboratory procedure. This test procedure was designed to simulate jet engine conditions.

A clean metal test specimen was placed in the exhaust opening of a tubular burner fueled with the control fuel, JP-S containing 2.58 grams/gallon of manganese as (methylcyclopentadienyl)manganese tricarbonyl. The burner was ignited and the test specimen was exposed to the exhaust stream until a certain amount of fuel was burned. The test specimen was then removed from the exhaust stream and weighed. The total weight of deposit formed was determined by subtracting the weight of the clean test piece from the test piece after exposure to the exhaust stream.

A second clean test specimen was placed in the exhaust opening of the jet burner, now fueled with a JP-S fuel composition containing (methylcyclopentadienyl)manganese tricarbonyl and an organic molybdenum compound. The jet burner was ignited and the test piece was exposed to the exhaust stream until an amount of this fuel equivalent to the control fuel was burned. The coated test piece was then removed from the exhaust stream and weighed. The amount of deposit was determined by subtracting the clean test piece weight from the coated test piece weight. Data for a series of such tests is presented in Table 1 below.

TABLE 1 Effect of Molybdenum on Deposit Amount of deposit Test Fuel Composition deposit reduction 1 JP- Mn compound" 82 mg. 2 Example 4 53 mg. 35% 3 Example 5 56 mg. 32% 4 Example 6 60 mg. 27%

(l) 2.58 grams/gallon of Mn as (methylcyclopentadienyl) manganese tricarbonyl.

The data in Table 1 clearly illustrates the deposit reducing effectiveness of the organic molybdenum compounds. Comparable deposit reduction is obtained using other molybdenum compounds as described herein.

The method and fuels of the present invention are fully described above. It is intended that this invention be limited only within the spirit and lawful scope of the following claims.

CLAIMS 1. A method of reducing manganese containing deposits formed on the surface of a jet engine from burning a fuel containing a smoke reducing quantity of a cyclopentadienyl manganese tricarbonyl, wherein the cyclopentadienyl radical has up to 17 carbon atoms; which comprises adding to said fuel prior to burning, a deposit reducing amount of organic molybdenum compound selected from the group consisting of l. molybdenum chelates and 2. molybdenum salts of a. phenol and C -C alkyl substituted phenols b. phosphoric acids having the formula wherein X, X, X and X are independently selected from O and S and R and R are independently selected from hydrocarbon alkyl and aryl groups having from one to about 30 carbon atoms c. hydrocarbon carboxylic acids having from five to about 24 carbon atoms, and

d. naphthenic acids, and burning the fuel in said engine.

2. The method of claim 1 wherein the amount of organic molybdenum compound present is sufficient to give an atomic ratio of manganese to molybdenum of from about 5:1 to about 1:2.

3. The method of claim 2 wherein said organic molybdenum compound is molybdenum naphthenate.

4. The method of claim 2 wherein said organic molybdenum compound is a molybdenum dialkylphosphorodithioate.

5. The method of claim 2 wherein said cyclopentadienyl manganese tricarbonyl is (methylcyclopentadienyl)manganese tricarbonyl.

6. The method of claim 5 wherein said organic manganese compound is a molybdenum salt of said phosphoric acid.

7. The method of claim 6 wherein two of X, X, X and X of said phosphoric acid are S and wherein said atomic ratio is 4:1 to about 1:1.

8. The method of claim 5 wherein said molybdenum compound is molybdenum naphthenate and said atomic ratio is from about 3:1 to about 1:1.

9. Jet fuel containing a smoke reducing quantity of a cyclopentadienyl manganese tricarbonyl, wherein the cyclopentadienyl radical has up to 17 carbon atoms and manganese containing deposit reducing amount of organic molybdenum compound selected from the group consisting of l. molybdenum chelates and 2. molybdenum salts of a. phenol and C alkyl substituted phenols b. phosphoric acids having the formula wherein X, X X and X are independently selected from O and S and R and R are independently selected from hydrocarbon alkyl and aryl groups having from 1 to about 30 carbon atoms 0. hydrocarbon carboxylic acids having from S to about 24 carbon atoms, and d. naphthenic acids, wherein the amount of said manganese compound and said molybdenum compound is sufficient to give an atomic ratio of manganese to molybdenum of from about 5:1 to about 1:2.

10. The jet fuel of claim 9 wherein said molybdenum compound is molybdenum naphthenate.

11. The jet fuel of claim 9 wherein said molybdenum compound is a molybdenum dialkylphosphorodithioate.

12. The jet fuel of claim 9 wherein said manganese compound is (methylcyclopentadienyl)manganese tricarbonyl.

mg Wrap mm raramr omen QEEIIW 'CAM Cl @Chfittfldfi Patent No. 5s 7 A Datad February 27, 975

' m Vincent F, Hnizda I: la certified that error appaara in the above-identified patent and that @aid Letters Patent are hereby corrected as shown below:

In Column 1, lines 54-56 that portion of the formula a? reading:

H P P II should read H In Column 5; line 57 case should read base In Column 7, lines 65-67 (Claim 1) that portion of the formula reading:

P I P Y r X3 .X II'" should read H In Column 8, lines 45-47 (Claim 9) that portion of the formula reading:

X 3 II should read H Signed and sealed this 10th day of July 1973.

(SEAL) Attest: n

EDWARD M.F.LETCHER,JR. ene Tegtmeyer Attesting Officer Acting COmmiSS I Patents

Claims

2. The method of claim 1 wherein the amount of organic molybdenum compound present is sufficient to give an atomic ratio of manganese to molybdenum of from about 5:1 to about 1: 2.
2. molybdenum salts of a. phenol and C1-C12 alkyl substituted phenols b. phosphoric acids having the formula
2. molybdenum salts of a. phenol and C1-C12 alkyl substituted phenols b. phosphoric acids having the formula
3. The method of claim 2 wherein said organic molybdenum compound is molybdenum naphthenate.
4. The method of claim 2 wherein said organic molybdenum compound is a molybdenum dialkylphosphorodithioate.
5. The method of claim 2 wherein said cyclopentadienyl manganese tricarbonyl is (methylcyclopentadienyl)manganese tricarbonyl.
6. The method of claim 5 wherein said organic manganese compound is a molybdenum salt of said phosphoric acid.
7. The method of claim 6 wherein two of X, X1, X2 and X3 of said phosphoric acid are S and wherein said atomic ratio is 4:1 to about 1:1.
8. The method of claim 5 wherein said molybdenum compound is molybdenum naphthenate and said atomic ratio is from about 3:1 to about 1:1.
9. Jet fuel containing a smoke reducing quantity of a cyclopentadienyl manganese tricarbonyl, wherein the cyclopentadienyl radical has up to 17 carbon atoms and manganese containing deposit reducing amount of organic molybdenum compound selected from the group consisting of
10. The jet fuel of claim 9 wherein said molybdenum compound is molybdenum naphthenate.
11. The jet fuel of claim 9 wherein said molybdenum compound is a molybdenum dialkylphosphorodithioate.
12. The jet fuel of claim 9 wherein said manganese compound is (methylcyclopentadienyl)manganese tricarbonyl.
13. The jet fuel of claim 12 wherein said molybdenum compound is a molybdenum salt of said phosphoric acid wherein two of X, X1 , X2 and X3 are S and said atomic ratio is 4:1 to about 1:1.
14. The jet fuel of claim 9 wherein said molybdenum compound is molybdenum naphthenate and said atomic ratio is from about 3:1 to about 1:1.