US1982420A - Fuel for internal combustion engines - Google Patents

Description

Patented Nov. 27, 1934 PATENT OFFICE FUEL FOR INTERNAL QOMBUSTIO ENGINES Jean Felix-Paul cle La Riboisiere, Paris, France No Drawing. Application November 16, 1931, Serial No. 575,474. In Great Britain December 6 Claims.

This invention relates to fuels for internal combustion engines, consisting mainly or essentially of liquid aliphatic or petroleum hydrocarbon material with the addition of a proportion of an aromatic amine, for the purpose of reducing knocking.

The employment of aromatic amines in association with liquid hydrocarbon material for preventing knocking is claimed in the British Specification No. 140,041 and it has been proposed also to introduce anilineinto fuels of the alcohol ether type.

The observation on which the invention forming the subject-matter of British Letters Patent No. 257,613 is based is that by the addition to liquid hydrocarbons of small proportions of aniline or a corresponding aromatic amine and an alkyl ether or ketone the tendency of the hydrocarbon material to exhibit knocking is con- 'siderably reduced.

The proportion of aniline or a corresponding aromatic amine needed sufficiently to suppress knocking varies in the case of different hydrocarbon materials and, moreover, the solubility of aniline in different hydrocarbon materials varies considerably, aniline being substantially if not completely insoluble in hydrocarbon materials free from so-called aromatics, as naphthenes and paraflins are for practical purposes non-solvents of aromatic amines. For-instance, it has been found that at low temperatures the more readily the aromatic amines separate from hydrocarbon material in which they have been dissolved, the lower is the proportion of aromatics present therein. I It is particularly in connection with fuels containing a relatively low proportion of aromatic hydrocarbons or free from aromatic hydrocarbons that it is necessary to resort to the use of agents adapted to suppress knocking and the proportiorf of such agents required to a large extent will be conditioned by the content of aromatics in the hydrocarbons.

The employment of small proportions of ether or acetone or like keton in association with aromatic amines assists in promoting their solution in hydrocarbon materials but increasein the proportion ofether to secure this end is open to ob jection as 1.180 is an increase in the proportion of ketone us\ i. v

The'use of a wide variety of other solvents for assisting the; solution of aniline in paraffin hydro carbon in has been suggested but many of the proposed i ents are unsuitable for use on a practical s l a on account of their high cost, while others, for instance, ethyl and methyl alcohol in the form in which they have hitherto been usually available in commerce are inoperative.

It has now been found that by the employment of relatively small proportions of ethyl or methyl alcohol in the completely or substantially anhydrous state, the solution of a suitable proportion of aniline or a like aromatic amine or a body isomeric therewith in hydrocarbon materials which are normally non-solvents or poor solvents of such amines may be facilitated.

The invention, therefore, may be stated to consist in a fuel for internal combustion engines consisting essentially of hydrocarbon material and containing a proportion of an aromatic amine or an azocyclic compound adapted to suppress knocking" in association with substantially anhydrous ethyl or methyl alcohol in a proportion which is small relative to the hydrocarbon material and in the absence of iron carbonyl or like 5 I metal compounds possessing anti-knock properties.

Generally, it may be stated that the ethyl or methyl alcohol must be of, at least, 99.5 per cent. strength.

Normally in accordance with the invention the substantially anhydrous ethyl or methyl alcohol will be present in the fuel in a proportion not considerably exceeding the proportion of aromatic amine therein.

Generally, the proportion will not exceed twice the weight of the amine and in practice a ratio of between 1.2 and 1.5 parts by volume per one part by volume of aromatic amine will be found sufficient.

In this connection it may be remarked that the ratio of substantially anhydrous ethyl or methyl alcohol to aromatic amines above referred to may be increased without exceeding the scope of the invention, but by increasing the proportion of alcohol the necessity for introducing a proportion of an aromatic amine would ordinarily be reduced.

Optionally, together with anhydrous ethyl or methyl alcohol there may be present in the fuel a proportion of an ether or ketone and where ether or a ketone is present in the fuel it will be usually found that the proportion of alcohol necessary to secure solution of the amine in a particular hydrocarbon mineral oil may be diminished.

Further, the proportion of alcohol necessary will depend within certaindimits upon the constitution and character of the hydrocarbon mano terial constituting the main or essential constituent of the fuel. v

In producing fuels in accordance with the invention in many cases it will be found more convenient or profitable to employ, instead of anhydrous alcohols in a substantially pure state, fuels which are at present on the market in Europe and which contain relatively large proportions of anhydrous alcohol in association with hydrocarbons; as well as certain of the fuels sold in other countries on a commercial scale and which are of the character above indicated.

Generally, the amine present in the fuel will be aniline or toluidine. V

While generally aromatic-amines properly so called will normally be used in accordance with the invention, pyridine, methyl pyridine, or other azocyclic hydrocarbons, may be employed; their use, however, is open to objection if only on account of their unpleasant smell.

While the invention is mainly of value or advantage when applied to the production of fuels consisting essentially of petroleum hydrocarbon material or containing large proportions of hydrocarbon material substantially free from socalled aromatics, that is to say, hydrocarbon materials which are mainly or solely of a parafiinic or naphthenic character and which, therefore, are poor solvents of aromatic amines, the invention is not to be regarded as limited to fuels the hydrocarbon constituent of which consists wholly or mainly of material of the character specified, as commercial or other considerations may render it desirable to employ in the preparation of fuels in accordance with the invention hydro-' carbon material containing a proportion of arcmatics.

The following particulars in accordance with the invention are given by way of example- To a petroleum hydrocarbon distillate having a suitable boiling range there is added aniline and 99.8 per cent. ethyl alcohol in a proportion adapted to yield a product containing 1.5 per cent. by volume of the former and between 1 and 2 or 2 and 2.5 per cent. by volume of the latter, such addition having the effect in certain cases of reducing knocking equivalent to the addition of a proportion of from 25 to 35 per cent. of benzol.

If, instead of ethyl alcohol as such in the preparation of the fuel, consisting essentially of hydrocarbon material, alcohol and aniline, there is used a mixed fuel such as is at present marketed.

in Europe which contains a relatively large proportion of anhydrous alcohol to the mineral oil hydrocarbon distillate there may be added aniline and a proportion of such a mixed fuel to yield a product containing the same in the respective proportions of 1.5 per cent. and 3 to 5, for instance 4 to 4.5 per cent., by volume. 1

To a hydrocarbon distillate'possessing a suitable degree of volatility for use with existing carburetors for internal combustion engines and poor in aromatics, aniline, acetone and substantially anhydrous ethyl alcohol are added to yield a mixture containing, respectively, 1.5, 0.2 and 0.8 per cent. by volume, the addition of aniline, acetone and substantially anhydrous ethyl alcohol in these proportions having the effect of sup- "1 pressing knocking such as can be obtained by), the addition of from 30 to 45 per cent. of benzol'fi,

If, instead of ethyl or methyl alcohol, a commercial fuel containing aliphatic hydrocarbons and an alcohol is employed with aniline and acetone the proportions of these ingredients should be, respectively, of 1.5, 0.2 and 2 per cent. by volume.

Fuels in accordance with the invention do not 5 possess the objectionable properties of fuels containing up to, for instance, 50 per cent. of alcohol,

in that they do .not operate to cause the pistons, piston rings and cylinders to run dry nor do they cause pitting of the valves which is particularly noticeable with fuels of high alcohol content operating at high speeds for instance 4,000 revolutions per minute.

Fuels in accordance with the invention have, on the contrary, the advantage of maintaining the pistons, piston chambers, and spark plugs clean, thus favourably influencing ignition and avoiding deposits of carbon and, further, they contain the amines in a perfect state of dissolution even at very low temperatures.

Having now described my invention, what I claim as newv and desire to secure by Letters Patent is:-.

1. A fuel for internal combustion engines consisting of petroleum hydrocarbon material of the character of gasoline together with a small proportion of an aromatic amine and a small proportion of a substantially anhydrous alcohol containing not more than two carbon atoms in its molecule.

2. A fuel for internal combustion engines consisting of petroleum hydrocarbon material of the character of gasoline together with a small proportion of an aromatic amine and a small proportion of substantially anhydrous ethyl alcohol.

3. A fuel for internal combustion engines consisting of petroleum hydrocarbon material of the character of gasoline containing a proportion of an aromatic amine and a proportion of ethyl alcohol of at least 99.5 per cent. strength within the limits of 1.2 to 1.5 parts for each one part by volume of the aromatic amine present.

4. A fuel for internal combustion engines consisting of petroleum hydrocarbon material of the character of gasoline containing a proportion of an aromatic amine in the neighbourhood of 1.5

per cent. and a proportion of ethyl alcohol of at least 99.5 per cent. strength within the limits of 1.2 to 1.5 parts for each one part by volume of the aromatic amine present.

5. A fuel for internal combustion engines consisting of petroleum hydrocarbon material of the character of gasoline together with a small proportion of an aromatic amine, a small proportion of substantially anhydrous ethyl alcohol and a small proportion of acetone.

6. A fuel for internal combustion engines con-