US3011881A - Novel boron compounds and motor fuel containing the same - Google Patents

Description

. to deposits, but

United States Patent Oflice 3,011,881 Patented Dec. 5, 1981 3,011,881 NOVEL BORON COMPOUNDS AND MOTOR FUEL CONTAININ THE 5 Donald D. Emrick, Shaker Heights, Chien-wei Lino, Beachwood, and Edwin 0. Hook, Chagrin Falls, Ohio, assignors to The Standard Oil Company, Cleveland,

Ohio, a corporation of Ohio No Drawing. Filed May 3, 1960, Ser. No. 26,439 6 Claims. (C1. 44-63) and wherein R represents a radical selected from a group consisting of alkyl, alkenyl, or alicyclic radicals containing from 7 to 21 carbon atoms, and R is selected from a group consisting of hydrogen or an alkyl radical containing up to 5 carbon atoms.

Gasolines containing one or more of the compounds of the present invention are effective in markedly reducing many of the adverse effects resulting from combustion chamber deposits which accumulate during the prolonged operation of an initially clean engine on a hydrocarbon fuel, and particularly a hydrocarbon fuel which contains tetraethyl lead as an octane improver. One of the most serious adverse effects of lead deposits is uncontrolled ignition and a general lack of smoothness in engine operation caused principally by these deposits becoming heated to incandescence within the combustion chamber during engine operation and igniting the fuel either before or after the portion in the cycle at which the charge would normally be ignited by the spark of the sparkplug. The boron compounds of the present invention are helpful in overcoming in great part this adverse effect of lead deposits.

It is well known that organoboron compounds are effective in minimizing engine operating problems due many of the boron compounds 'previously proposed for such use are not suitable in commercial practice due to the characteristic instability of organoboron compounds toward hydrolysis while in gasoline. Because of this instability, contact with small amounts of water and moist, atmospheric conditions during prolonged storage causes many of the prior art compounds to hydrolyze to solid insoluble products which precipitate out of the gasoline phase, so that the boron content never reaches the engine where it might be efiective. In contradistinction to this general characteristic of boron compounds, the compounds of the present invention are quite stable toward hydrolysis while in gasoline and are well suited for conventional large scale manufacturing and marketing operations.

Additionally, gasolines containing boron compounds of the present invention are highly effective in minimizing carburetor icing, usually making it unnecessary to incorporate a speciat additive in the gasoline to guard against this problem. Carburetor icing represents a troublesome problem attendant to automotive engines operated in cool, moist, atmospheric conditions. This icing problem is most likely to occur during engine warmup when the engine is temperature. The vaporization of the gasoline in the carburetor during this warmup period produces temperature reduction in the throttle plate and carburetor walls, causing the moisture present in the incoming air on cool, humid days to condense and freeze. Such ice formation restricts the narrow openings in the carburetor, manifesting itself in a rough idling condition and frequent engine stalls.

The gasoline base stocks to which the present boron compounds are added may be any of those conventionally used in preparing a motor gasoline for a sparkignited internal combustion engine, such as catalytic distillate, motor polymer, alkylate, catalytic reformate, isomerate, naphthas, etc. The gasoline will preferably contain a tetra alkyl lead compound as an anti-knock agent and a scavenging agent. The amount of anti-knock agent will usually be at a level of approximately 3 ml./ gal. but may range from ml./gal. up to 6 mL/gal. The base gasoline may also include other common additives such as anti-oxidants, stabilizers, solvent oils, dyes, and the like.

The amount of the boron compound added to the fuel may vary and the amount is preferably expressed in terms of boron. Generally an amount of the compound to provide 0.002% by weight of boron (based on the total fuel) is the smallest amount that will give any significant effect. Use of amounts in excess of 0.1% by weight of boron usually cannot be justified economically. These compounds may be added directly to the fuel or, if more convenient, they may be dissolved in a suitable solvent to produce a liquid concentrate and the concentrate blended in with the fuel.

The compounds of the invention are prepared by reacting boric acid with a mono-acylated trialkanol amine compound in an equimolar relationship. The monoacylated trialkanol amine compounds employed in this reaction may be characterized by the following general formula:

wherein R and R are defined as hereinbefore. The latter compounds are preferably prepared by reacting a trialkanol amine compound with a fatty acid or naphthenic acid compound containing 8 to 22 carbon atoms in a 1:1 molar ratio under conditions to remove the water of reaction that'is formed. Compounds prepared by reacting triethanol amine or triisopropanol amine with oleic acid are particularly desirable for the gasoline compositions of the present invention. Commercial grades of the preferred fatty acids which are derived from naturally occurring fats and oils are suitable for the reaction, and hence the R radical in the above formula may correspond to the fatty acid radicals present in such fats and oils. The R radical may also be suitably derived from naphthenic acids containing from 8 to 22 carbon atoms.

The mono-acylated trialkanol amine compound readily undergoes boration under conditions in which the water of reaction is removed from the reaction mixture as it below normal operating 4 is formed. The reaction proceeds in accordance with Example 2 the equation: 141 grams (0.5 mole) of oleic acid was mixed wit] (1) 95.8 grams (0.5 mole) of tri-isopropanol amine togethe: H 11' cHr-oH-orr HO with 300 m1. of benzene in a three-necked flask. Th1: N reaction mixture was heated with stirring at the azeotropn P distillation temperature to remove 8.8 ml. of water (9.(

CHPCEFOH HO ml. represents theoretical or 0.5 mole).

31 grams (0.5 mole) of boric acid was then added tc the flask containing the mono-acylated amine and the R CHr-( JH-O reaction mixture was heated again to the azeotropic disg B OH+2H2O tillation temperature and maintained under these conditrons until 2% mols of water of reaction was removed CHPCILO for each mole of mono-acylated amine and boric acid re- 1 acting. The excess solvent was then removed from the or the equation: reaction mixture and the product was a clear plastic III.

N 1 1 CHr-CH-OH HO zit-G-O-OH-OIh-N +2 BOH CHs-CH-OH HO R R H R cm-c'xn-o o-oH-cH| 11' f RCO( JHCH:N B-o-B N-cHr-t m-0-c-R+sm0 CHs-CH-O o-cH-c I depending upon the amount of water that is removed substance which was readily soluble in gasoline. The during the reaction. product has the formula:

CH OH: cm 0Hr-oH-o o-oH-cm CH: f CnHn-C-O-(EH-CHr-N B-O-B -CHr- H--O-C-C17Hs:

cm-cn-o o-cH-c I The water of reaction may be removed by simple boil- The following tests were conducted to show the benefits ing but it is preferable to remove the water by means of available by the use of these compounds in gasoline with azeotropic fractional distillation using preferably benzene, respect to suppressing surface ignition and protecting toluene, or xylene as the solvent. Boric oxide may be against carburetor icing. used in place of the boric acid as the boron source in the To illustrate the improvemcms toward Surface ignition above reactions with the proper adjustment of the molar SIIPPI'QSSiOH, tests in all ASTNFCFR Single cylinder engine relationship With the mohwacyiated triaikanoi amine having a compression ratio adjusted at 12:1 were emcompouni ployed. Preparatory to the test cycle the engine was run The preparation of these compounds will be better thmmiat for 9 minutes to i f the understood in connection with the following examples. engine commons for the test period i' this the engine was operated at open throttle continuously for Examplg 1 three hours,b during vlvhich time the total surface ignition count was 0 served e ectronicall All ex rimental congrams mole) of R1810 flcld was i Wlth ditions were the same for each test except the gasoline. grams mole) of pr p o me 111 the The base fuel in each test was the same and had the presence of 80 ml. of xylene. The reaction mixture was following composition and specifications. heated with stirring at the azeotropic distillation tem- Composition.

perature until 3.2 ml. of water of reaction was removed (3.6 ml. represents theoretical or 0.2 mole). 00 333 5 3? a fi i 12.4 grams (0.2 mole) of boric acid was then added 19% 1 naphtha to the mono-acylated amine and the reaction mixture was 6.5% 1:. alkylatg heated again to azeotrope out 2.0 moles of water for each 4.2% isopentane mole of mono-acylated amine and boric acid reacting. 3.5% butane The reaction mixture was filtered and the excess solvent 5 Tetraethyl lea ------.ml./gal-- 2.4 was then removed. The resulting product was a trans- API B y 57.8 parent viscous material which was completely soluble in 8 distmflfiml gasoline. The product has the following formula: 131,- 91 10% 122 cm 30% 170 0 on. om-dn-o 50% 229 cums- -o-on-car 13-03 38; 281

CHr-CH-O E P Reid vapor pressure 11.24

The number of surface ignitions in the additive fuel is expressed as percentage of the surface ignitions of the blank fuel with the results as follows:

It is obvious from the above table that the boron compounds of the present invention are highly efiective in reducing both total and audible surface ignition with gasoline containing the same.

To demonstrate the carburetor anti-icing virtue of gasoline containing these compounds, 11 test procedure was devised simulating the stop-and-go type of engine operation normally experienced by the motorist during the engine warmup period. The test was conducted in a 1955 Plymouth V-8 engine equipped with a two-barrel carburetor. Carburetor air was supplied at a constant rate of 70 cubic feet per minute by a specially designed air conditioner controlled at 42 F. and 90% relative humidity, which are temperature and humidity conditions considered highly conducive to carburetor icing. test conditions were the same except for the gasoline.

The test consisted of running the same number of cycles on each fuel where in each cycle the engine was operated at 2200 r.p.m. for seconds and then decelerated normally to an idle at 450 r.p.m. for a maximum of 30 seconds. Performance of the engine was observed during each idle period, and -a numerical rating based on the degree of rough idling and engine stalls was assigned so that each fuel received a merit rating on a scale ranging from 100 to 0. By this scheme an engine operating with a smooth idle over the idle periods of every test cycle would receive a rating of 100, and an engine which stalled in less than 12 seconds in the idle period of every test cycle would receive a rating of 0.

The base fuel used had the following composition and specifications.

Composition:

40% 1t. cat. distillate 40% full range reformate 8.3% It. naphtha 8.3 isopentane 3.4% butane It is to be understood that various modifications of the foregoing invention will occur to those skilled in the art upon reading the above description. All such modifications are intended to be included as may be reasonably covered by the appended claims.

We claim:

1. A leaded gasoline for a spark-ignited internal combustion engine containing a boron compound of the following general formula:

where X is selected from the group consisting of hydrogen and R, 15 o-hH-on, a o

-n N-cn -hH-o-o-a o-orr-on,

CHr-CHg-O where X is selected from the group consisting of hydrogen and in an amount equivalent to 0.002 to 0.1% by weight boron.

3. A leaded gasoline for a spark-ignited internal combustion engine containing a boron compound of the following general formula:

0 CH: CH: H-O

C11Hss- -O(!HCH:N B--0X CHr-CHO where X is selected from the group consisting of hydrogen and CH: OJJHCH1 CH; 0 -n NoH,-hH-0o-c"m,

0-CH-C s :1 an amount equivalent to 0.002 to 0.1% by weight oron.

4. A novel boron compound having the following general formula:

to 0 R CHr- H-O R-i'J-O-hH-cm- B-OX CHr-CH-O 7 where X is selected from the group consisting of hydrogen and R! 0HCH, R' f B NcHiJ:H-0-G-R O- CH-CH:

and wherein R represents a radical selected from the group consisting of alkyl, allrenyl, and alicyclic radicals containing from 7 to 21 carbon atoms, and R is selected from the group consisting of hydrogen and alkyl radicals containing up to 5 carbon atoms.

5. A novel boron compound having the following general formula:

CH -CHr-O B-OX cm-cm-o where X is selected from the group consisting of hydrogen and O i CnHsr--O-CHrCHg- 6. A novel boron compound having the following general formula:

References Cited in the file of this patent UNITED STATES PATENTS 2,741,548 Darling et al Apr. 10, 1956 2,939,877 Washburn June 7, 1960 2,942,021 Groszos et al. June 21, 1960 2,948,597 Belden Aug. 9, 1960

Claims (1)

1. A LEADED GASOLINE FOR A SPARK-IGNITED INTERNAL COMBUSTION ENGINE CONTAINING A BORON COMPOUND OF THE FOLLOWING GENERAL FORMULA: