US1701620A - Motor fuel and process of making same - Google Patents

Description

Tatented Feb. 12, 1929.

NITED TATQES LESTER KIRSCHBRAUN, OF CHICAGO, ILLINQISL Moron FUEL AND rnocnss or MAKING sans.

No Drawing. Application filed January 8, 1920, Serial No. 350,229. Renewed July 5, 1928.

This invention relates to improvements in motor fuels and process of making same and refers more particularly to a motor fuel made from the so-called pressure distillate obtained from the cracking of hydrocarbon oils. It has been Well recognized in the art that hydrocarbons heavier than gasoline, as for example, kerosine, gas oil and fuel oil, obtained from the fractional distillation of crude petroleum, contained more power for use in explosive engines than does gasoline. Two serious difiiculties have prevented the utilization of these heavier fuels for use in internal combustion engines. First, the use of these heavy fuels tends to quickly carbonize the engine and secondly, the fuel must reach a relatively high temperature before it can be vaporized and explosion take place. In a sense, one is really the corollary of the other for the reason that imperfect combustion takes place, resulting in the precipitation of carbon. The addition of a substantial percentage of gasoline helps but all at tempts to use these high boiling point hydrocarbons in high grade internal combustion engines have failed.

lln the cracking of petroleum oils, the vapors are passed out of the still to the condenser and thence to the receiver, where they are condensed and collected, which are called pressure distillate. This pressure distillate, in a sense, may be called synthetic crude. In commercial operation of cracking hydrocarbon oils, it is now carried on in a very extensive scale, approximately 50% of the pressure distillate is gasoline or gasolinelike character While the remaining 50% are the heavier ends, consisting in portions of kerosene-like bodies, gas oil bodies, and fuel oil bodies and a small per cent of relatively heavy residue. The cracking operation should, of course, be so regulated as to avoid as far as possible any of these relatively heavy residues or tarry-like bodies.

This pressure distillate as such is not used for motor fuels. The light ends or the gasoline content thereof are fractionally distilled OE and then this fraction, which as stated ma be 50% of the pressure distillate, is washed with dilute sulphuric acid, caustic soda and water and then generally blended with a small amount of casinghead gasoline, before it is in a marketable condition. The remaining portion of. the pressure distillate is distilled down to coke and the distillate obtained from this second distillation put back into the pressure stills to form part of the new charging stock and rerun as before. It is well known that the production of this pressure distillate necessitates the use of considerable quantities of fuel, inasmuch as the cracking operation takes place under relatively high pressure at high temperatures.

Among the objects of the present invention are to provide a process which will make pressure distillate and then convert it into a motor fuel, preferably, as a single and continuous operation; to provide a process which obviates many of the steps necessary to convert pressure distillate into marketable motor fuel; to provide a motor fuel which will have more power than ordinary gasoline but which, at the same time, will not carbonize the cylinders; to provide a motor fuel which can be economically made and in general to provide improvements of the character referred to.

One manner of carrying out the process is as follows: Gas oil from the Kansas field of say, 30 Baum gravity, is placed in a still and heated to an oil temperature of 750 with a pressure of say, 90 pounds, and the distillation continued until one half of the initial gas oil charge has been vaporized, passed out of the still and condensed and collected in the receiver. By suitably subjecting the vapors in their passage from the still to the condenser, to dephlegmation or reflux condensing action, the gravity of the pressure distillate may be regulated so as to produce pressure distillate having a gravity of52 Baum. tillate, while still relatively hot, passes from the condenser to a second still where it is fractionally distilled to vaporize all but the very heavy ends, i. e., those of a tarry-like nature. The distillate from this second or fractional distillation is then passed through a mechanical mixer which may be merely a kettle equipped with mechanical agitators so as to vigorously stir the material.

An emulsifying agent is added to the distillate in the agitator, as for example, 1% of naphthenic acid. Water is then added, preferably in a gradual manner, to the pressure distillate contained in the agitator so as to form an emulsion in which the pressure distillate forms the continuous phase and the water the dispersed phase. If the pressure distillate is relatively clean -,,the second distillation, i. e., the fractional distillation, may be entirely omitted and the pres- This pressure dis sure distillate passed directly from the first receiver to the mixer or agitator where it is emulsified.

The pressure distillate, after being emulsified, as above stated, is ready for use. It can be put in an internal combustion engine of a motor car and used in exactly the same way as gasoline. Actual road tests with motor fuel made from 50 degrees gravity pressure distillate obtained by the cracking of as oil from the mid-continent field with a rich mixture showed a decided saving on fuel consumption without carbonizing the cylinders. This emulsion contained substantially 3% to 5% of water. With the same mixture in the same car, ordinary gasoline of commerce under like conditions, produced only 10 to 12 miles to the gallon of gasoline.

One of the particular advantages of this motor fuel is the enormous saving in refining costs over that now necessary to convert pressure distillate into a marketable prod-' not. It is to be understood that the water in the emulsified condition, is very finely and evenly distributed throughout the hydrocarbon and it is the addition of this water that permits of the utilization of this crude pressure distillate as a motor fuel.

I claim as my invention:

1. A fuel for internal combustion engines, consisting of an emulsion of pressure distillate obtained from the cracking of hydrocarbon oils, water and naphthenic acid as an emulsifying agent.

2. A fuel for internal combustion engines, consisting of an emulsion of pressure distillate obtained from the cracking of hydro LESTER KIRSCHBRAUN.