US3158451A - Gasoline containing organic boronphosphorus additive - Google Patents

Description

United States Patent O 3,158,451 GASGLINE CONTAINLNG URGANHC BQRGN- PHOSIHORUS ADDITIVIE Richmond T. Bell, Grayslfie, 113., assignor to The lfure Oil Company, Chicago, TEL, a corporation of Qhio No Drawing. Fiied Aug. 4, 1958, Ser. No. 753,087 10 Claims. (Cl. 44-69) This invention relates to new and useful improvements in gasoline compositions and more particularly to a gas line containing a small amount of a boron-phosphoruscontaining additive in an amount sutficient to reduce spark-plug and other deposits in the combustion area and mitigate the deleterious effects of such deposits, reduce octane-requirement increase, increase the life of exhaust valves, and modify combustion area deposits to mitigate the deleterious effects of such deposits.

Modern high-compression engines require fuels which are much superior to those in use only a few years ago. Modern premium gasolines are specially compounded to utilize hydrocarbon components having high octane numbers are usually formulated with lead tetraethyl, or other antiknock agents, to produce a fuel composition having a very high octane rating. It has been found, however, that the additives Which are used in modern gasoline compositions contribute to the formation of deposits in gasoline engines which result in uncontrolled combustion, octane-requirement increase, and spark-plug fouling. To combat these undesirable effects, a variety of additives have been used in gasolines to mitigate or eliminate certain of these deleterious efiects. However, since a variety of undesired conditions are involved, a number of different additives have previously been required to mitigate said conditions.

It is therefore one object of this invention to provide a superior gasoline composition by incorporating therein a small amount of a hydrocarbon-soluble organic compound of phosphorus and boron.

Other objects of this invention will become apparent from time to time throughout the specification and claims as hereinafter related.

This invention consists of a new and improved gasoline composition produced by incorporating in gasoline an additive consisting of a hydrocarbon-soluble, nonpyrophoric organic compound of phosphorus and boron. The additive is incorporated in the gasoline in a concentration varying from 0.0001 to 0.2% with a concentration of 0.001 to 0.1% being preferred. Additive compounds which are useful in accordance with this invention have the general empirical formula B P l-I R in Which R is a C -C hydrocarbyl radical, in and n are small integers, x is a small integer or zero, y is a small integer, and x+y is equal to the free valences of B and P. Classes of compounds which fall within this formula include hydrocarbyl-substituted phosphine-boranes, hydrocarbyl-substituted phosphinoboranes, and polymers thereof, and hydrocarbyl derivatives of phosphonium borohydride. In these compounds, the hydrocarbyl substituents may be located on either the boron or phosphorus atom or both. When a gasoline composition is prepared using one of the additive compounds of this invention, it has superior antiknock properties, substantially reduced tendency toward the accumulation of combustion-area deposits, including spark-plugs, and greatly inhibits the deleterious effects of lead-containing engine deposits, viz, uncontrolled combustions including rumble, starting knock, pre-ignition, after-running, etc., and minimizes octane requirement increase (the increase in octane number required by an engine to avoid knocking upon accumulation of deposits in the combustion area.

While the additives of this invention may be used with gasoiines containing no other additives, the principal commercial use of the additives is in leaded gasoline compositions. The term leaded gasoline compositions is used herein in its generally accepted technical and commercial sense, viz., a gasoline containing lead tetraethyl and a scavenger such as ethylene dibromide, ethylene dichloride, or mixtures thereof. A premium-leaded gasoline which may be used as the base fuel for the gasoline composition of this invention consists of a blend of gasoline components from one or more of the following processes: straight distillation of crude oil, catalytic cracking, thermal cracking, isomerization, alkylation, polymerization, reforming, hydrogenation, etc., e.g., a blend of v. of gasoline from fluid catalytic cracking (also referred to as FCC) and 20% v. of gasoline-range alkylate. To prepare a typical premium gasoline, there is added to a blended gasoline as just described 1.0-3.5 ml. per gallon of commercial tetraethyl lead fluid (a typical composition being 61.48 wt. percent tetraethyl lead, 17.86 wt. percent ethylene dibromide, 18.81 wt. percent ethylene dichloride, and 1.85 wt. percent kerosene, dye, and impurities); l10 lb./ 1000 bbl. of an oxidation inhibitor, e.g., alkyl phenylene diamines, and alkyl aminophenols, such as N-n-butylpara-aminophenol; 0.25-05 lb./1000 bbl. of a metal deactivator, e.g., salicylidene propane diamines, such as N,N'-disalicylidene-1,2-propanediamine; 0.05-0.5 lb./1000 bbl. of a corrosion inhibitor, e.g., t-amine salts of carboxylic acids, such as the imidazoline salt of polymerized linoleic acid in an aromatic solvent; 5-50 lb./1000 bbl. of an antiwear agent e.g., esters of aromatic carboxylic acids, such as dibutyl phthalate, and 1% of an anti-icer (optional for winter fuel compositions), e.g., lower alcohols or mixtures of alcohols and ethers, such as isopropanol, isopropanol-methanol mixture, isopropanol-isopropyl ether mixture. The boronphosphorus-containing additive of this invention may be added to a gasoline containing none of the above additives or containing any or all of the additives in any combination.

Additives which may be used in accordance with my invention are compounds of boron, phosphorus, carbon, and hydrogen, i.e., hydrocarbyl derivatives of boron and phosphorus hydrides, which are soluble in hydrocarbons to the extent of at least 0.0001%. These compounds include the hydrocarbyl-substituted phosphine-boranes, hy-

drocarbyl-substituted phosphinoboranes, and polymers.

thereof, and hydrocarbyl derivatives of phosphonium borohydride, in which the hydrocarbyl substituents contain from 1 to 10 carbon atoms. The general empirical formula for compounds of this type is B P H R in which R is a C1-C hydrocarbyl radical, m and n are small integers, x is zero or a small integer, y is a small integer, and x+y satisfies the free valences of B and P for the particular compound. Specific examples of the classes of boron-phosphorus-containing compounds which may be used include the following:

(l) Phosphine-boranes of the formula xR P.xBR

where the Rs represent the same or different hydrocarbon radicals and one or more (but not all) of the Rs may be hydrogen, and the xs may be the same or different integers.

(2) Phosphine-boranes, derived from diborane and higher boranes, of the formula BXHX+4JZPR3, where x is where the Rs represent the same or different hydrocarbyl radicals, or one or more (but not all) of the Rs may be hydrogen, and the is may be the same or different small integers, preferably l-4.

(3) Phosphinoboranes of the formula [R PBR [(R P) BR],,, [(R P) B] where the Rs represent the same or different hydrocarbyl radicals, and one or more (but not all) of the Rs may be hydrogen, and x is a small integer including one. Some of the compounds covered EXAMPLE I A gasoline blend was prepared consisting of 80% v. fluid catalytically cracked gasoline and 20% v. alkylate having added thereto 3 ml. tetraethyl lead fluid (i.e., tetraethyl lead plus ethylene dihromide and ethylene dichloride) per gallon of gasoline. A portion of this gasoline (7.5 gal.) was provided with 5 g. tri-n-butylphosphineborane, (C H P:BH producing a concentration of 0.3 theory of phosphorus.

The gasoline containing the tri-n-butylphosphine-borane additive was evaluated in a one-cylinder COT test-engine. In each test run, the engine was operated continuously under conditions tending to produce maximum deposits until fouling of the spark plug occurred and the length of time of the run before fouling was noted. The test engine was operated for 40 hours without any sign of spark plug fouling, at which time the fuel was exhausted. A similar run was made with the gasoline blend without the tri-nhutylphosphine-borane additive and the spark plugs were fouled in 20 hours (average of 3 runs). The gasoline containing the tri-n-butylphosphine-borane additive, not only mitigates spark-plug fouling, but also reduces uncontrolled combustion and substantially reduces the increase in octane requirement of an engine, i.e., substantially inhibits octane requirement increase. It is thus seen that the tri-n-butylphosphine-borane additive is a multipurpose additive for inhibiting spark-plug fouling, uncontrolled combustion, and octane requirement increase.

EXAMPLE II A number of gasoline compositions are prepared using both leaded and unleaded gasoline containing various boronphosphorus compounds as additives. These compositions are shown in Table 1.

duced effectiveness per unit of compound added at high levels. The additives of this invention are very effective for the purposes indicated when present in gasoline, either leaded or unleaded, in concentrations of 0.0001 to 0.2 wt. percent, with concentrations in the range of 0.001 to 0.1 Wt. percent being preferred.

Some of the compounds covered by the aforementioned class are pyrophoric, and hence are impractical for commercial utilization. For example, dimethylphosphine tri methylborane and dimethylphosphine dimethylborane are spontaneously inflammable in air, and hold little interest as commercial gasoline additives. Others, such as the trimers and tetramers of dialkylphosphinoboranes and the trimers of dialkylphosphinodialkylbcranes, are not only non-pyrophoric and tractable in open air, but are exceptionally stable thermally. Compounds with character istics such as these are preferred for the motor fuel compositions of this invention. It is to be further noted, however, that even the compounds which are pyrophoric are operative for the purposes of this invention, though inconvenient to use. Some of these compounds which are pyrophoric in concentrated or pure form are not pyrophoric when dissolved in gasoline in the very low concentrations used in this invention.

While I have described my invention fully and completely as required by the patent statutes with special emphasis upon several preferred embodiments thereof, I wish it understood that Within the scope of the appended claims, this invention may be practiced otherwise than as specifically described.

What is claimed is:

1. A gasoline containing an antiknock quantity of tetraalkyl lead and a small amount, suflicient to suppress preignition, of an organic boronand phosphorus-containing compound having the general formula:

wherein n is a value selected from the group consisting of 0 and 1 and m is a value taken from the group consisting of 3, l and 0, when n is l, m being selected from the group consisting of 0 and 1, when n is 0, in being 3; wherein R is selected from the class consisting of hydrogen and alkyl radicals, at least one of said R group representing Table I Gasoline Leaded (3 ml. Additive (0.005% w. of phosphorus) TEL/gal.)

8O 20 FCC Alk late Methylphosphine-borane [CHaHsPZBHz].

/ o- L "Zn". Dimethylphosphine-borane [(GHMHP BEE].

FCC SO/QLETOC/Isopentane o 60140 Straight Disti no /Allrylat.e 70l 3gsRetormate/Alkylate o 'Irimethylphosphine-borane [(OHmP: BB3]. Tetramethylphosphoniumborohydrido [(CHmPBHQ. Tetraniethyl phosphoniunl tetramethyl porane [P(C:I3)4B {CHM}, Dimethylphosphlnedimethylborane [(6.53) 2B1: BH(CH.-,)z]. Phosphinodimethylborane polymers [HzPB(CHs)2]:. Mcthylphosphinoborane polymers ICHaPHBHZh.

Dimethyl hospliinoboraue trimer [(CHK)2PBHE]3. Dimethylphosphinoborane tetramer [(CHQ)PBH2]4, Phosphinomethylborane polymers lHgPBfiCfiah.

. Methylphosphinodimethylborane [CH3HPB(CE3)2].

Dimethylphosphinoclimethylbnrane trimer [(CHQZPMCHQQJK. Dimethylphosphinomethylborane polymers [(CBQZPBHC- lillx.

When any of the fuel compositions set forth in Table I are used in the COT test engine, the rate of spark-plug fouling is found to be decreased by 25 to or more. Likewise, when the fuel compositions set forth in Table I are used in an automotive engine over an extended period, octane requirement increase is effectively mitigated. It is also to be noted that certain of the hydrocarbyl-substituted boron-phosphorous additive, such as the dimethylphosphinodimethylborane trimer, provides some increase in octane rating of the fuel as Well as mitigating octane requirement increase, reducing uncontrolled combustion, and reducing spark-plug fouling. Because of the exceptional effectiveness of these additives, only very small con-- ical and the remaining radicals are of the group consisting of hydrogen and (D -C hydrocarbyl radicals.

4. A leaded gasoline containing 0.0001-02 wt. percent of a compound of the formula B H .nPR, where x is 5 2 to 10, w is 1 to 4, and R is of the group consisting of hydrogen and C -C hydrocarbyl radicals.

5. A leaded gasoline containing 00001-02 wt. percent of tributylphosphine-borane.

6. A leaded gasoline containing of dialkylphosphine-borane.

7. A leaded gasoline containing 00001-02 wt. percent of the trimer of a dialkylphosphinoborane, [R PBH where R is a C C alkyl radical.

8. A leaded gasoline containing 00001-02 wt. percent of the tetramer of dialkylphosphinoborane, [R PBl-l h, where R is a C -C alkyl radical.

9. A leaded gasoline containing 0.0001-02 wt. percent of the trimer of dialkylphosphinodialkylborane,

0.000l0.2 wt. percent [R PBR h where R is a C -C alkyl radical.

10. A leaded gasoline containing 0.000l0.2 wt. percent of (CH PBH References Gited in the file of this patent UNITED STATES PATENTS OTHER REFERENCES Chemical Reviews, vol. 58, No. 1, February 1958, Stability Relationships Among Analogous Molecular Addition Compounds of Group III Elements, by Stone, pages 101-129.

Claims (1)

1. A GASOLINE CONTAINING AN ANTIKNOCK QUANTITY OF TETRAALKYL LEAD AND A SMALL AMOUNT, SUFFICIENT TO SUPPRESS PREIGNITION, OF AN ORGANIC BORON- AND PHOSPHORUS-CONTAINING COMPOUND HAVING THE GENERAL FORMULA: