US2608524A - Process for producing superior motor fuel - Google Patents

Description

Aug- 26, V1952 PQH. JOHNSON ErAL PROCESS FOR PRODUCING SUPERIOR MOTOR FUEL Filed May 7. 1948 Patented Aug. 26, 1952 PROCESS FOR PRODUCING SUPERIOR MOTOR FUEL raul Hilton Johnson, Bartlesville, Okla., .and Glenn J. Forseth, Spring Valley, Wis., assignors to Phillips Petroleum Companys@ corporation of Delaware Application May 7, 1948, Serial No. 25,594

(Cl. 196;. 5m`

l` Claims. 1

This invention relates to a process for the manufacture of an improved motor fuel. In one of its more specific-aspects, it relates to a process for the manufacture of motor fuels for internal combustion origines.V In a preferred embodiment,

this invention relates, to the manufacture of an automotive gasoline fuel .of superior road nat- It is Well knownthat in actual use, motor fuels of similar octane number will often give widely varying performance. The reason that the superior qualities of certain `motor fuels do not show up in the laboratory is due tothe inadequacy of the present testing methods.` "It is generally considered that a motorofuelV which Will knock the least is superior,` and knocking is most apparent when an automobile is being accelerated 'and when the load `on the engine is constantly changing. The knocking tendency of fuels as they are tested in the laboratory is determined with a motor operating. ata relatively constant speed and at a constant load. Therefore, knocking data relative to acceleration` and changing load are not obtained. Thus, the, only entirely satisfactory testing method known at the present time is in stock automoblleengines under conditions of actual rcadratingtest i.` e. driving the automobile and actually` determining how the motor fuel acts under allroad conditions. This type of test gives conclusive data as to the value of a motor fuel in actual service.

By such road rating tests, it has been determined that the variation in performance of inotor fuels of the same octanenumber is dependent to a great extent "onthe olefin content. It has been found that motorfuels containingsubstantial amounts of olefin hydrocarbons in the low boiling range and substantial amounts of aromatic, iscparaffinic,` and/or naphthenic hydrocarbons in the high boiling range produce superior low and high `speed performance in lnternal combustion engines of the type used in automobiles. the maximum boiling point of the olenic components should not be in-excess of about 250 F., the approximate mid-boiling' point of gasoline motor fuel. The idealfuel then, might be presumed to consist `of approximately 50 per cent olens boiling below 250 F. and 50 vper, cent aromatic, isoparainic, and/or naphthenic materials boilingr above 250 F, i

Broadly speaking, our invention comprises a single step catalytic cracking process for the manufacture of a superior road rating motor fuel. We have discovered that a `mixture of Further, it has been found thatl naphthenic naphtha and heavy gas oil contacted with a suitable dehydrogenation-cracking catalyst, such as bauxite, which will cause dehydrogenation, cracking, and aromatization, produces a superior automotive fuel.

In this specification, the term in'aphthenic naphtha as 'referred to means a mixture which includesa substanital proportion of those hydrocarbons known as naphthenes or cycloparaffins. By definition, naphtha is a mixture ofilowboiling hydrocarbons and is a term well known to those skilled in the art. Also used in this specification is the term gas oilff This may be either a virgin or synthetic gas oil which is a suitableA cracking stock. i

`In accordance with our invention, a mixture `of naphthenic naphtha comprised of cyclic parafiins having a boiling range of 250 to 400 F. and a'gas oil comprised primarily of paraflins boiling infthe range of'450 to 750 Rin a ratio of naphtha-to gas oil'of 1:5 to 5:1, however, preferably within the 'range of 1:2 to 2:1, is contacted under cracking conditions with a suitable dehydrogenation-cracking catalyst such as bauxite. The naphtha-gas oil mixture is charged to a suitable `cracking unit lat a temperature in the range of 800 to 1l00 F., but preferably between 900 and 1050 F., e. pressure in the range of 0 to 300 pounds per square inch, but preferably between-20 and 100 pounds per square inch, and a space velocity of from 0.5 to`5 liquid volumes of charge per volume of catalyst per hour. The total eiiluent from the cracking reaction is fractionated by suitable fractionation mea-neto separate the normally gaseous materialsyfa superior road rating motor fuel, and heavy materials boiling above 400 F. which may be wholly orinar- 'tially recycled as desired.

The action of the catalyst on the charge stock is primarily one ofA cracking, dehydrogenation, andaromatization; The gas oil by this treatment cracked `and dehydrogenated, thereby forming a predominance of olensboiling below the mid-boiling point of gasoline. The naph- `thenic-naphtha portion ofthe charge stock `beying inherently somewhat refractoryis partially aromatized, thus giving both aromatics and naphthenes as products.` The aforesaid fractionation of the total'eiiluent produces a gasoline boiling range fraction of which the low-boiling half is comprised primarily of oleflns and the higher-boiling half primarily of aroma-tics and `naphthenes.` This catalytic treatment of the naplithenic naphtha produces only very mino-r iportions'of paraiiins and oleiins.`

Conventional catalytic cracking equipment is satisfactory for the operation of this invention. Suitable means should be provided for maintaining the desired temperatures, pressures, and other conditions required by the process in the various Zones.

An object of this invention is to provide a process for manufacturing a superior motor fuel.

Another object is to provide a method for producing an improved motor fuel having a high road rating at all speeds.

Another object of this invention is to provide a method for manufacturing an improved motor fuel which exhibits superior performance characteristics over the entire speed range, in an internal combustion engine, particularly during periods of acceleration.

A further object is to provide a method for manufacturing a superior internal combustion engine fuel from naphthenic naphtha and heavy gas oil.

A further object is to provide a method for producing a superior motor fuel by a catalytic process.

A further object is to provide a one step catalytic process for the manufacture of motor fuel.

A further object is to provide a method for manufacturing a superior road rating motor fuel by -catalytically treating a mixture of naphthenic naphtha and gas oil.

Further objects and advantages of this invention will be apparent to one skilled in the art from the accompanying disclosure and discussion.

A better understanding of some ofthe many aspects of our invention maybe had by referring to the attached schematic iiow diagram in conjunction with the following discussion. It is understood that While this is representative in general of our process, various minor changes may be necessary in adapting it to the various conditions Within the scope of the invention.

Naphthenic naphtha and steam (20 to 100 pounds per barrel of hydrocarbon feed) or other diluent are introduced into line I2 through lines I and Ii, respectively, where they are admixed with heavy gas oil introduced through line I2. The hydrocarbon-'diluent mixture passes via line I2 through preheater I3 and is introduced to catalytic cracking zone I4 at a temperature in the range of 800 to 1l00 F. and a pressure in the range of 0 to 300 pounds per square inch. The mixture is contacted with a suitable catalyst, such as granular, calcined bauxite, which will cause dehydrogenation, cracking, and aromatization. Effluent from catalytic cracking means I4 is passed through line I5 to separation means I6. Light gases are removed through line Il, gasoline through line I8, water through line I9, and heavy residue through line y2l). If desired, the heavy residue may be removed through the outlet in line 20 or recycled through lines 2I and I2 and preheater I3 to catalytic cracking means I4.

Advantages of this invention are illustrated by the following example. VThe reactants and their proportions, and other specic ingredients are presented as being typicaland should not be construed to limit the invention unduly.

Example in the range of 458 to '725 F. Column 2 shows the properties of a gasoline produced by treating a 250 to 400 F. straight-run naphthenic naphtha. Column 3 shows the properties of a blend of the gasolines produced in runs l-and 2, properties of which are shown in columns 1 and 2. Column 4 gives the properties of a gasoline vproduced by treating a 1:1 blend of the gas oil and naphtha used in runs 1 and 2.

Column 1 2 3 4 ASTM Distillation, F.:

IBP l 99 137 115 119 5% evap. 760 mm 124 220 162 164 10% 139 247 190 191 50% i l i 252 309 296 299 365 361 259 307 P 402 408 396 408 ASTM Octane Number 0 cc. TE l 77. 0 46. 6 57. 8 60.9 1 cc. TEL 79. 5 56.0 65. 5 67. 8 3 cc. TEL 81.3 65.7 73.1 73.8 Research Octane Number: v

TEL .1 48.5 60. 4 63. 5 55. 9 69. 1 7l. 1 68. 4 77. 6 78. 7 52. 7 53.8 53. 2 Brominc Number 9 33 34 A comparison of the above data shows an improvement inthe ASTM and Research octane number of the product gasoline from the combined treatment of the gas oil and naphthenic naphtha over that of the product of the separate treatment ofthe naphtha, or a combination of the products of the separate treatment of the gas oil and naphtha. The separate treatment of the gasoil provides the highest octane numbers of all, but it also shows a too high per cent of olefins. boiling above 250 F. as indicated by the bromine number. This excess of olens shows up disadvantageously in the road rating tests. Along with the improvement in octane numbers 'of the gasoline product of the combined treatment is the improvement in road rating as may be shown by road tests. A further improvement is one of economics rather than in product. .It is quite obvious that it would be much cheaper to have only one catalytic treating unit rather than two for the treatment of the gas oil and naphthenic naphtha separately.

Although the processV has been described and exemplified in terms of its preferred modications, it is understood that various changes may be made without departing from the spirit and scope of the disclosure and of the claims.

We claim:

l. A process for the manufacture of a superior road rating motor fuel, which comprises forming a mixture of naphthenic naphtha boiling within a range of 250 to 400 F. and gas oil boiling within a range of 450 to '750 F., said naphthenic naphtha and gas oil being mixed in a ratio within the range of 1:5 to 5:1, contacting said mix' ture with a. bauxite catalyst at a temperature in the range of 900 to 1050o F. and a pressure in the range of 0 to 300 pounds per square inch so as to produce an eiiiuent, the gasoline fraction of which consists of a low-boiling half comprising primarily olens and a higher boiling half comprising primarily aromatics and naphthenes, and recovering said gasoline fraction as a product of the process.

2. A process for the manufacture of an improved road rating gasoline motor fuel, which comprises forming a mixture of naphthenic naphtha boiling within a range of 250 to 400 F., gas oil boiling within a range of 450 to 750 F., and an inert diluent, said naphthenic naphtha and gas oil being mixed in a ratio Within the range of 1:2 to 2:1, preheating said mixture to a temperature in the range of 900 to 1050o F., contact- 3. A process for the manufacture oi an improved road rating gasoline motor fuel, which comprises forming a mixture of naplithenic naphtha boiling in the range of 250 to 400 F., a virgin gas oil boiling in the range of 450 to 750 F., and steam diluent, said naphtlienic naplitha and Virgin gas oil being mixed in a ratio in the range of 1:2 to 2:1, preheating said mixture to a temperature in the range of 900 to 1050 F., contacting said mixture with a bauxite catalyst at a pressure in the range of 20 to 100 pounds per square inch and a liquid space velocity of 0.5 to 5 Volumes per volume of catalyst per hour so as t0 produce an eilluent, the gasoline fraction of which consists of a 10W-boiling half comprising primarily oleiins and a higher boiling half comprising primarily aromatics and naplitlienes, and recovering said gasoline fraction as a product of the process.

4. A process according to claim l., wherein a steam diluent is used along with said naphthenic naplatlia and said gas oil.

' PAUL HILTON JOHNSON.

GLENN J. FORSETH.

REFERENCES CITED The following references are or record in the file of this patent: Y

UNITED STATES PATENTS Number Name Date '2,283,854 Friedman et al May 19, 1942 2,385,325 Bailey Sept. 25, 1945 2,404,595 Richker et al July 23, 1946 2,406,112 Schulze Aug, 20, 1946 OTHER REFERENCES Chemical Constituents of Petroleum, by Sachanen (pages 1.97 and 200), Reinhold Pub; Corp., N. Y., 1945.

Claims (1)

1. A PROCESS FOR THE MANUFACTURE OF A SUPERIOR ROAD RATING MOTOR FUEL, WHICH COMPRISES FORMING A MIXTURE OF NAPHTHENIC NAPHTHA BOILING WITHIN A RANGE OF 250 TO 400* F. AND GAS OIL BOILING WITHIN A RANGE OF 450 TO 750* F., SAID NAPHTHENIC NAPHTHA AND GAS OIL BEING MIXED IN A RATIO WITHIN THE RANGE OF 1:5 TO 5:1, CONTACTING SAID MIXTURE WITH A BAUXITE CATALYST AT A TEMPERATURE IN THE RANGE OF 900 TO 1050* F. AND A PRESSURE IN THE

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