US2040396A - Treatment of hydrocarbon oils - Google Patents

Description

Patented May 12, 1936 UNITED STATES PATENT OFFICE,

2,040,396 TREATDIENT OF HYDROCARBON OILS Jacque C. Morrell and Gustav Egloif, Chicago,

111., assignors, by mesne assignments, to

Uni-

versal Oil Products Company, Chicag'mfIlL, a corporation of Delaware No Drawing. Application December 26, 1981 Serial No. 583,400. Renewed April 5, 1934 v e 6 Claims.

a process for treating hydrocarbon mixtures un- I dergoing decomposition and conversion'reactions or the lower boiling vaporous products of these 10 reactions to produce substantial amounts of compounds which add materially to theanti-knock.

value of the gasoline finally produced from the process.

While the cracking process as at present gen- 15 erally practiced in the petroleum industry tends to the production of gasoline having anti-knock characteristics superior to those possessed by corresponding gasoline fractions produced by the straight run distillation of crude petroleums, it may frequently happen that the production of a cracked gasoline of a knock rating rendering it saleable as a premium motor fu el may entail the use of relatively severe cracking conditions with attendant increased. losses in fixed gases and 25 coke and a decrease in the overall yield of the desired product. In the majority of cases for any given stock charged to the cracking process there exists an optimum set of conditions for producing a maximum yield of gasoline of good anti- 30 knock value, the use of more severe conditions, while they may produce gasoline boiling range fractions closely approximating a mixture of aromatic hydrocarbons in composition, producing not only excessive gas losses but a very material 35 lowering in yield of gasoline so that in this respect it may be stated that the production of increased yields of anti-knock gasoline by the cracking process is limited by economic considerations, Y 40 The present invention has as one of its objects provision of a process by which the'economic disadvantages of producing high anti-knock value gasoline by cracking may be offset by the production concurrently in the cracking processof com- 45 pounds having a specially high anti-knock value so that theproduct of the operation considered as a whole is of the high quality desired and the necessary yields are maintained.

In one specific embodiment the invention comprises treating cracked hydrocarbon vapors with ammonia and halogen derivativesof aromatic hydrocarbons in the presence of catalysts to produce amines which increase the anti-knock value. of the gasoline. 55 The halogen derivatives which it is preferred to use are the monoor poly-chlor substitution products of the lower or base members of the aromatic series such as benzene, toluene, xylene, ethyl benzene, etc. In the reaction of these compounds with ammonia (or ammonium hydroxide) the chlorine'of the hydrocarbon derivative reacts with one hydrogen atom of the ammonia radical to form hydrochloric acid, the ammonia residue NH: then taking the place formerly occupied by the halogen to form an amine according to the following general equation:

RCl-l-NmZRNHH-HCI in which R represents anymon ovalent hydrocar bon radical either of the alkyl or aryl groupsglli. I

though the latter are preferred on account of the" higher effect upon the knock rating of gasolines of their corresponding amines. To insure the progress of the reaction to the formation of amines it will be evident that an excess of ammonia is necessary to neutralize the hydrochloric acid formed.

- Numerous metallic catalysts may be employed such as the heavy metals, iron, nickel, cobalt, zinc, cadmium, copper, mercury, manganese, chromium, vanadium, etc., and their oxides and salts, copper salts such as copper sulfate or copper chloride being specially adaptable. In the selection of a particular catalyst for any given set of conditions the operator will be best guidedby experience though it may be stated that the copper compounds mentioned'have given uniformly good results in a large number ofcases. Similarly it may be found advantageous to utilize the catalysts mixed with or supported upon relatively inert spacing material to insure maximum surface action.

Several alternative methods of operation are possible and are comprised within the scope of the invention. As a general rule, the conditions under which the general reactions are brought 7 about correspond to those of cracked vapors undergoing fractionation under super-atmospheric pressure following the reaction zone of a cracking process, these conditions involving tempera- 45 tures of from approximately 300 to 600 F. and pressures in the approximate range of 100 to 400 lbs. per square inch. According to one method of operation the vapors entering a primary fractionator or separator may receive increments respectively of chlorinated hydrocarbons and at approximately the same point the proper amount of ammonia, the vapor mixture then being passed over or through catalytic material of suitable character. Preferably the vapors are subseon anti-knock value is measured by the percentage increase in the H; U. C. R. (highest useful compression ratio). 'It will be observed that the greatest'efiect is produced by methyl aniline and xylidine though their eflects are only slightly above that of aniline as the simplest member of the series and which would result from the interaction of chlorbenzol and ammonia.

PERCENTAGE INCREASE or H. U. G. R.

With No. I petrol obtained by addition of 5% by volume of common organic substances selected with reference to solubility and boiling point 0 Melt- Boil- C t cal Effect ing ing ri i on Name of substance formula point point point C H. U. 0 o. 0.11.

6 184 433 dry +21, 7 57 194 432-442 +22. 2 Ethyl aniline CsHnN -63 204 425-415 +10. 4 Di-methyl aniline.-- CaHnN +2 195 420-409 +1. 7 Di-ethyl aniline"--- Cw isN 38 216 411-390 0 Benzyl aniline :HnN +33 310 Decomp. 470 +9. 5 Toluidine C7H|N 21 2(1) 1 +18.3 xylidine (M) C|H N +49 215 448 +22. 3

It is contemplated to use mixtures of hydro-.

carbon derivatives which are adaptable to use in the process, for example, light coal tar. distillates may be chlorinated and introduced into I the cracking vapors; along with ammonia as already described without resorting to the usually tedious methods of separation of individual hydrocarbons by fractionation. The particular hydrocarbon derivative or mixture of such employed in the process and the amount used will depend upon a variety or Iac- I tors such as the cost of the compound or mixture, the character of the cracked products (which in turn depends upon the character of the charging stock and the conditions of operation) and the knock rating desired in the finished gasoline.

Chlorbenzol is of general application, as the ani-; line which results from it by reaction with ammonia has a high efiect on the anti-knock value oi. a given gasoline, this being only slightly exceeded by such compounds as cumidine, xylidine, monomethylaniline, toluidine, etc., as shown by thetable.

In addition to the production of amines which add to the anti-knock value of the gasoline, other treating eflects may be produced incidental to the use of certain catalytic mixtures, particularly the compounds of copper which have given good results. For example, cracked vapors may be desuli'ur'ized to a considerable extent within the capacity of the metallic contact mass either to the extent of merely sweetening the vapors by conversion of mercaptans to disulfides or further desuliurizing action may occur. The extent oi. these reactions will depend upon the chemical character or the cracked vapors being treated, the relative amounts of reagents used and other conditions of operation.

The process of the invention may be used .as a single treatment on cracked vapors or in combination with preceding or succeeding treatments for producing as an overall result. a finished product of desired characteristics. For example, the vapors may be treated by special desuliurizing and/or polymerizing steps prior to the introduction of the reactants for the production of amines and still further vapor phase treatments, suitable settling periods or filtering by inert or adsorbent materials may follow. In the majority of instances a final rectification to produce an end point gasoline is preferable. Furthermore the condensed product may require a light final washing to remove traces of reaction products.

As an example of a treatment which may be conducted according to the process of the invention and the results obtainable therefrom, the cracked vapors of approximate gasoline boiling point range coming from the fractionator of a cracking process operating an Mid-Continent residuum may be considered.' Such vapors may be evolved from the fractionator under a pressure of approximately 225 pounds per square inch and a temperature of 525 F. Monochlorbenzol may be injected into these vapors at the rate of about 12 pounds per bbi. of final distillate along with approximately 2 pounds of ammonia, injected either in concentrated aqueous solution or as the dry gas, the vapors then being passed through a treating chamber containing finely divided .copper to catalyze the reactions for the production of amines, then to settling and filtering chambers and finally to a fractionator in which the desired high antiknock gasoline is produced as an overhead fraction. The gasoline produced by fractionating and contacting these vapors with solid adsorbent materials without the use of chlorbenzol and ammonia upon the vapors according to the process of the invention may have the properties shown in the "untreated column following, while gasoline produced by applying the process or the invention may have the properties shown in the treated column.

The. yield of gasoline in both cases may be approximately of the residuum processed,

with the maximum cracking temperature employed 930 F. with a pressure of 250 pounds per square inch. .To produce the 80 octane number by straight cracking and fractionation without the addition 01' a special treating reagent according to the process 01. the invention it may entail a reduction in yield to approximately 52%, which is a serious consideration in commercial work and which might render the process uneconomical. Thus the application 01 the present invention is shown to have a definite commercial value.

The foregoing general description 01' the process of the invention and the example of the results obtainable by one operation thereof is sufllcient to enable one skilled in the art torecognize its value but since the exact type of operation strued in any way as a limitation upon the bro scope of the invention. 1

We claim as our invention:

1. In the cracking of hydrocarbon oils by heat I and pressure wherein cracked vapors containing gasoline are separated from residuum, the meth- 0d which comprises introducing a halogenated aromatic hydrocarbon and ammonia to the cracked gasoline vapors after their separation from the residuum, reacting the halogenated hydrocarbon andammonia in a vapor zone of the cracking process where the vapors are at a temperature of from 300 to 600 F. to form an amine, and condensing and collecting the gasoline vapors containing the amine thus formed.

3. In the cracking of hydrocarbon oils by heat and pressure wherein crackedvapors containing gasoline are separated from residuum, the method which comprises introducing a halogenated hydrocarbon and ammonia to the cracked gasoline vapors after their separation from the residuum, reacting the halogenated hydrocarbon and ammonia in the presence of a. catalyst having a refining action on the vapors and in a vapor zone of the cracking process where the vapors are at a temperature of from 300 to 600 F. to form an amine, and condensing and collecting the gasoline vapors containing the amine thus formed.

4. In the cracking of hydrocarbon oils by heat and pressure wherein cracked vapors containing gasoline are separated Irom residuum, the method which comprises introducing a chlorinated hydrocarbon and ammonia to the cracked gasoline vapors after their separation from the residuum, reacting the chlorinated hydrocarbon and ammonia in a vapor zone of the cracking process where the vapors are at atemperature of from 300 to 600 F. to form an amine, and condensing and collecting the gasoline vapors containing the amine thus formed. a

5. In the cracking of hydrocarbon oils by heat and pressure wherein cracked vapors containinggasoline are separated from residuum, the method which comprises introducing a chlorinated aromatic hydrocarbon and ammonia to the cracked gasoline vapors after their separation from the residuum, reacting the chlorinated hydrocarbonand ammonia in a vapor zone of the cracking process where the vaporsare at a temperature of from 300 to 600 F. to form an amine, and condensingand collecting the gasoline vapors containing the amine thus formed.

6.rIn the cracking of hydrocarbon oils by heat and pressure wherein cracke'dvapors containing gasoline are separated from residuum, the method which comprises introducing a chlorinated hydrocarbon and ammonia to the cracked gasoline vapors after their separation from the residuum, reacting the chlorinated hydrocarbon and ammonia in the presence of a catalyst having a refining action on the vapors and in a vapor zone or the cracking process where the vapors are at a temperature of from 300 to 600 F. to form an amine, and condensing and collecting the gasoline vapors containing the amine thus formedl JACQUE C. MORRELL. GUSTAV EGLDFF.