US2356952A

US2356952A - Conversion of petroleum oils

Info

Publication number: US2356952A
Application number: US426602A
Authority: US
Inventors: Smith William Alvah
Original assignee: Individual
Current assignee: Individual
Priority date: 1942-01-13
Filing date: 1942-01-13
Publication date: 1944-08-29
Anticipated expiration: 1961-08-29

Description

Aug. 29, 1944. w. A. SMITH 2,356,952

CONVERSION OF PETROLEUM OILS Filed Jan. 13, 19 12 COOL ING F/PAC 77mm T/NG I A MED IUM TOWER i CONDENSER OVERHEAD REACT/0N 0/? FLASH CHAMBER HEA TING (O/L 44/170 ar 0/1. /va ACTIVATED 22 5:152 s cm )1 mm 0,? (w/vomsn r5) W 7 ll 00 T r/lva a/waso AUX/L/ARY Assn/r H07 6:4355 I 4 i A? pump STE/1M (Am/v5 o/e /X wmq- GASflLE/VE) 7 X7 Z6 M/VE/VTOIQ. WATER of 7- m M cur arm/4cm!) 2 g V 5 Patented Aug. 29, 1944 UNITED STATES PATENT OFFICE 12 Claims.

This invention relates to the conversion, by controlled heat treatment, of petroleum oils into refined components with superior physical characteristics, which refined components may be separated according to their different boiling temperatures.

This invention is an improvement upon, and continuation in part of, my prior copending application Ser. No. 302,927, filed November 4, 1939.

One object of the invention is to improve the conversion of petroleum oils. Another object of the invention is to provide an improved method of controlled conversion and/or cracking of hydrocarbons, such as petroleum oil, which may be carried out by relatively simple and inexpensive apparatus, with which the overhead products obtained will have improved viscosity index, improved physical characteristics, with which one may obtain if desired a maximum possible proportion of light bodied lubricants of high quality, and a minimum proportion of less desirable heavy bodied oils, and which will be relatively simple, practical and efiicient.

Other objects and advantages will appear from the following description of some practical applications of the invention, and the novel features will be particularly pointed out hereinafter in connection with the appended claims.

Under the proper temperature and contact time relationships, lubricating oil bases are selectively cracked and rearranged to yield lubricating oils .having more desirable physical properties. This is eflected according to this invention, by subjecting the lubricating oil bases to reaction with acid activated clays under the proper temperatures and contact time conditions. Where the lubricating oil base contains deactivating components, such, for example, as sulphur, certain metallic compounds in small quantities are useful for neutralizing the deactivating properties of the undesirable components, and thereby substantially increase the activity of the acid ac tivated clay.

The acid activated clay permits degradation and separation of undesirable fractions and an non-solventized, is effected by this means.

case or bearings, because of the lower internal friction of the oil itself. Additives have been developed to improve, or raise the viscosity index but such materials in the quantities'specified, according to some literature published in connec- 15 tion with such a commercial additive, had substantially no efiect on flash, pour, carbon, color,

or other physical characteristics of the oil,

Additives of this type are usually added to the oils which initially have been improved by selective solvent extraction of the more desirable components, and to eliminate as large a proportion as possible of that portion having the unde-.- sired characteristics, but no improvement in the physical characteristics of the selected components is achieved by solvent extraction. On the contrary, actual physical improvement of the useful parts of the oil is achieved by the control of treatment permitted by the proper application of acid activated clay, either alone or in connection with proper amounts of auxiliary agents in finely divided form, such as metallic oxides or other chemicals of which copper oxide and aluminum oxide are common examples; the particular auxiliar agent is selected in accordance with the requirements of the material itself, so

that entirely new substances with markedly improved physical characteristics are obtained, with more or less complete elimination of undesirable or unstable compounds. Improvement in oils from naphthenic sources, both solventized and quality, it is well known that crude oils seldom contain lubricating components in the desired relationship to marketability. For example, Pennsylvania crude oil contains roughly twice as much heavy residual lubricating oil as it does of the so-called neutral or volatile lubricating component, yet the normal market demand from automobile and truck trade is for relatively light bodied lubricants containing a high proportion of light lubricating oil. At times the demand for heavy Pennsylvania residual oil is so small as to make the value of this oil to the refiner only slightly higher than that of fuel oil from much cheaper crudes, resulting in loss of revenue both to the refiner and the crude oil producer.

According to this invention the conversion and/or cracking of petroleum oils, and particularly the heavy bodied oils, can be effectively controlled and greater yield of the desirable components such as light bodied oils, obtained by performing the conversion and/or cracking in the presence of acid activated clay. The clay is, of course, in finely divided form and preferably fresh or unspent, or reactivated. It is mixed with the oil to be converted preferably while the latter is well below the natural cracking temperature of that oil, such as below 400 F'., and where an auxiliary agent in finely divided form is employed, it can be mixed with the clay and the mixture dispersed throughout the oil before the oil reaches the cracking temperature. The oil plus clay mixture is then subjected to cracking or conversion conditions and temperature. It is important for best results that the oil be in intimate contactwith the acid activated clay before the conversion starts. If the oil is heated approximately to the conversion or cracking temperature before being brought in contact with the clay, or there is no intimate mixture of the clay and the oil, the clay may be unable to effect satisfactory and complete control of the conversion, with the result that too much of the wrong fractions or components is produced and not enough of the more desirable components, such as the light bodied lubricants. The cracking or conversion temperature to which the base oil is heated will depend on various factors, such as the source and. character of the oil and the nature of the catalyst employed, which factors are well understood in this industry. By way of example, in the apparatus shown, temperatures of 800 F. to 890 F. in the transfer line and of 565 F. to 740 F. in the base of tower section I were employed to produce satisfactory results in treating Pennsylvania 600 S. R. oil.

Different oils require variations as to treatment, such as for example, quantities of activated clay, chemical modifiers, temperatures, time of reaction, and desired end results. Such variables must be determined experimentally. To enable those experienced in the art readily to apply. 7

the invention without undue experimentation, the data elsewhere herein concerning results obtained from the treatment of dewaxed Pennsylvania 600 steam refined stock are indicative.

In the accompanying drawing, the single figure is a schematic diagram of a simple system for performing this invention, which has been successfully operated.

In the drawing, the heavy bodied oil or crude oil to be treated is mixed with the acid-activated clay and placed in a tank or reservoir I0, and if an auxiliary agent is to be employed, it may also be mixed in finely divided form with the clay and the oil, so that the agent and the clay will be dispersed as much as possible throughout or suspended in, the oil to produce a pumpable mixture.

The mixture of the oil with the clay and agent dispersed therethrough is withdrawn from the tank I 0 through a conduit ll, controlled by a valve or gate l2, by means of a pump l3, and this pump delivers a stream of this mixture through conduit Hi to the lower end of a heating coil l5, which coil passes upwardly through a heating chamber I6. The upper end of the coil I5 is connected by a conduit or pipe I! also called a transfer line, to the upper end of a reaction or flash chamber I8 which is disposed vertically in a heating chamber l 9 that communicates with the heating chamber l6 by an aperture 20 in a partition 2| which divides the chambers l6 and I9 from one another. Hot gases are supplied to the lower end of the chamber. IS in any suitable manner, such as through a pipe or conduit 22 and after rising in the chamber l6, they pass through opening 20 in partition 2| to the upper end of the chamber I9, and then the gases descend to an outlet flue pipe or conduit 23 leading to the Smokestack. The distribution of gas travel is controlled by damper 24 in conduit 23, by valve 24a controlling opening 20; and valve 40 in pipe 39.

The showing of the direction of movement of the heating gases relatively to the oil and clay mixture is merely schematic, and actually their relative direction of movement will be largely opposite to one another according to counterflow principles and good engineering design to secure the most efficient heat exchange.

The bottom of the reaction or flash chamber [8 is provided with an outlet pipe 25 controlled by valve 26 through which the bottoms and suspended clay and any auxiliary agent, that is, the heavy residual oil in which the clay and agent are carried, are removed. These bottoms with clay are removed to any suitable reservoir for subsequent treatment to remove the clay and agent and to utilize the oil component of the mixture.

Frequently steam or vacuum can be used to facilitate the removal of volatile products, or lighter petroleum fractions can be used, particularly where a change in the character of the lighter fractions is desired. Recycling of lighter petroleum fractions enables the treatment on these fractions to be carried to any desired point, in spite of the fact that their vaporization characteristics might otherwise limit the feasible time and temperature relationship. In this way, long continued treatment of even gasoline fractions at temperatures of 500 F. or higher is possible, and the desired molecular changes achieved.

In this particular apparatus, as shown, steam under pressure may be admitted through pipe 21 into the lower end of the reaction or flash chamber 18, and the steam arising through this chamber not only aids the reaction but is of assistance in carrying off the lighter fractions or components into fractionating tower 28 having sections designated l, 2, 3, and 4. In application of the process, a greater or less number of sections may be employed, as conditions may require. This fractionating tower may be separate from the reaction or flash chamber, but connected at its lower end to the upper end of the flash chamwith different boiling ranges, and each outlet passes through a cooler 29. These reaction or flash chambers I8 and fractionating towers 28 with a number of overhead outlets such as A, B,

branch pipes

41, 48 and 49, controlled respectively by valves 50, 5| and 52, to the upper ends of sections I, 2 and 3 of the tower 28 so that vapors from different tower sections may be carried directly to the pipe 30 and thus by-passed directly to the condenser coil 3|.

Examples of results that can be achieved in accordance with this invention by the application of one pound of acid-activated clay to each gallon of heavy oil to control the alteration of dewaxed Pennsylvania 600 S. R. stock to produce relatively large amounts of high grade S. A. E. 20 motor oil and high grade Bright stock, are set ,forth in the table below, which tabulates the re- 34 by a pipe 35 and removed by a pipe 36 opensults oi three tests:

Orig on Test 110 Test 111 Test 112 dewaxed Penna.

S. A. E. S. A. E. 600 S. Bright S. A. E Bright Bright R. stock" stock 20 stock 20 g f stock Percent en"; 34 42. 7 4s 41. a 39.0 31. s Gravity, deg. B 25. 8 28. 5 27. 0 28. 4 27.2 28. 5 27. 4 Flash, deg. F 555 475 560 460 560 470 500 Fire, deg. F 625 555 630 535 630 550 670 Viscosity S. U.:

Secs. 100 deg. F i 377. 5 1, 956. 6 367. 6 1, 920. 2 343. 58 l, 904. 1 Secs. 210 deg. F 159 57. 64 140. 6 56. 64 136. 0 55. 93 138. 7 Viscosity index 99 102. 2 102. 9 99. 9 102. 4 103. 9 103. 6 Color, N. P. A. No Green 6 4 6 3 6 Com-adson carbon res., percent. 2. 4 0.32 15 0. 34 1. 17 0.31 I l. 31

ing out of the upperpart of the cabinet. The temperature to which the oil is heated in the coil l5 and in the reaction chamber 18 will depend upon the many factors well understood in the art, one of which is the character of the cracking agent, if one is employed. For example, some agents cause cracking at lower temperatures than others.

The flashing action may also be aided by introducing suitable amounts of water, or more highly volatile hydrocarbons such as gasoline and lighter fractions, into the mixture of oil and finely divided clay and agent,- before the oil and clay enter the heating coil l5. For example, the water or gasoline may be introduced through a pipe 3'! controlled by valve 38 into the pipe l4, and as this new mixture is heated in the coil 15, the water or highly volatile hydrocarbon will be heated to the vaporizing stage, and then when they reach the chamber l8 the Water or gasoline will pass off through the tower and carry some of the lighter components with them. The action in this respect is similar to that caused by the introduction of steam through the pipe 21, and, may replace or supplement the action caused by the steam admitted through pipe 21. It may also be desirable, at times, to separately control the temperatures in the chambers 16 and I9 and for that purpose the chamber I6 may have a direct outlet 39 at its top controlled by a valve 40, so that some of the gases from the chamber l6 may escape directly instead of passing through the chamber l9.

A heating medium such as a hot gas may be admitted to chamber l9 through a pipe 4| controlled by avalve 42. The pipe 30 at the top of the tower 28 is provided with a control valve 43, and at a point between the Valve 43 and the condenser coil 31 is connected by a pipe 44 to the transfer line IT. The line IT at a point between its connection to the pip 44 and the chamber I8, is provided with a controlling valve 45, and the pipe 44 is provided with a controlling valve 46. The pipe 44 in the zone between the valve 46 and the connection to the pipe 30 is connected by' Test also yielded 4% of kerosene, 8% of gas oil, a loss of 1.3%, 2% of 63.5 sec. viscosity 2 plus color nonvis neutral and 8% 0f #2 color neutral; test #111 yielded kerosene 2%, gas oil 6%, a loss of 1.4%; 2% of 77.4 sec. viscosity at 100 F. 3 color, nonvis neutral, and 2% of 166.1 viscosity at 100 F.; 4 /2 color neutral; test #112 yielded kerosene 4%, gas oil 10%, loss of 1.2%, 5.5% of 1 color nonvis neutral and 8.5% of 2 color neutral. It will be observed that the gravity of the S. A. E. 20 motor oils in all these cases is lower than is customary from pure Pennsylvania crude, yet the viscosity characteristics and flash and fire points are very substantially better; the extremely high flash and fire points of the bright stock from test #112 are notable. These tests indicate both of the important refining improvements mentioned above.

Tests 110, 111, 112 were made with the idea of making up a synthetic crude oil which was proportionally recombined where necessary and fil tered, then it was vacuum distilled in the laboratory. In the case of #110, the transfer line was directly connected to the condenser, with no steam being used. In the case of #111, 95% by volume of water was charged with the oil and clay, and the transfer line again connected directly to the condenser. In the case of #112, the oil and clay were charged to the heating coil while 95% by volume of water based on the oil and con verted into steam was 'charged into the base of the tower, and the overhead led to a condenser, by-passing

tower sections

1, 2, 3, and 4. When the level or column height of the liquid in the reaction or flash chamber reached approximately '7 feet, the samples of overhead condensate and bottom were proportionally combined and filtered to make the synthetic crude for laboratory evaluation.

In the accomplishment of any refining process, manufacturing and economic considerations virtually make mandatory continuous rather than batch operation, andthis process is very satisfactory in continuous operation. Both acid-activated clay and the chemicals disclosed herein can be made into a finely divided state suitable for mixing with oil and pumping through a pipe still. The essential difference between continuous operation in a pipe still and batch operation is that the whole volume of oil is subjected to the maxi- 5 mum temperature in pipe still operation, while in batch operation continuous evolution of volatile materials occurs as the temperature is raised beyond the point of initial volatility. Other variables, such as rate of charge, tube size, tube length, furnace exit temperature, etc., will occur to .the minds of persons skilled in the art.

In the case of tests #110, #111 and #112 above, and in the tests which follow, the essential data with reference to the still used are: tubes, total length from the furnace inlet including that in heating zone and transfer line to the point of entrance to the reaction or flash chamber, 3138 inches, of which 2162 inches was in furnace heating zone, and 130 inches transfer line length between furnace outlet and reaction chamber. The transfer lin discharged into a vertical reaction chamber made of 6" pipe at a point ten feet above the base, in which base was located the discharge line and the steam flashing line. Of course, the size and length of the reaction chamber may be varied to secure any desired time of contact, as may also the furnace constants and variables, or the level carried in the reaction chamber. If desired, the reaction chamber may be arranged for auxiliary heating, as indicated in the attached drawin preferably down draft from the furnace itself. If virtually complete volatilization of the oil from the reaction chamber is desired, the chamber may be arranged for the mechanical removal of the residual matter including clay and chemicals.

Separation of the overhead materials into components suitable for evaluation in the laboratory /z inch 1.,

was effected by passing the overhead in succession through a 6" x 12', a 6" x 12' and a 10 x12 tower, each with about 10' 6" broken tile reflux surface and followed by a condenser and receiver, with suitable by-pass arrangements so that up to four separations could be made in the overhead. A branched connection from the transfer line directly to a combined cooler and condenser enabled icy-passing the reaction chamber and all of the towers.

Runs or tests Nos. 110, 111, 112 were made for the purpose'of determining the effect of steam on the reaction. In test #110 the transfer line was directly coupled to the condenser causing the oils to thereby by-pass the reaction chamber and towers, and the total run into a drum on a scale where the recovery was identical with the charge. No steam was used except that from the clay. The transfer line temperature was 845 F. Test #111 was made with by-passed reaction chamber and towers, with 845 F. transfer line temperature, using parts by volume of water for each parts by volume of oil which wascharged under pressure into the oil and clay mixture through pipe 31 from an auxiliary pump (not shown). The oils under test #112 above were made with bypassed towers, furnace exit temperature of 845 F. approximately 7 feet oil level in reaction chamber, and close to 650 F. temperature in base of reaction chamber, with steam, approximately 95% by volume (condensed), or by weight of the oil charged, into the base of the reaction chamber. The overhead and reaction chamber bottoms were proportionally recombined, filtered, vacuum distilled and tested.

The results of additional tests similar to the foregoing have been summarized in the following table, divided endwise into two sections which should be placed side by side to be read:

Variables in results from treatment of dewared Pennsylvania 600 steam refined stock Test designation F G P N O 106 R G. C V S Acid activated clay, lbs. per gal 1% 1% 1% 1% 1% 1% 1 1% 1 Bauxite, lbs., per gal 87% coml cuprous oxide, gms. ea. gal Oil and chem., chg. rate, gal. per hr. 8.25 7.70 9. 27 9.7 11.38 18.87 9.16 13.05 14.06 13.43 Gasoline chg. rate, gal. per hr 8.00 Furnace outlet temp., deg. F. (av.) 800 820 840 855 879 845 840 855 840 840 Reaction chamber base temp., deg. F 673 681 673 673 693 673 694 738 721 702 Steam, per cent of oil charged 147 80. 4 72. 8 65. 8 17. 1 111. 0 22. 5 80. 7 70. 2

Bottoms:

Gravity, deg. B 26. 8 26. 7 27. 2 27. 7 27. 7 26. 7 27. 6 26. 5 25. 8 Flash, deg. F 600 595 610 595 630 570 620 '6 8 635 625 Fire, deg. F 680 675 680 670 700 660 695 '5 710 705 Viscosity, S. 188. 7 191.1 167. 2 158. 8 192. 3 156. 8 185. 6 E6 218. 5 217. 1 Viscosity index 105. 6 105. 3 107. 2 109. 3 110. 7 104. 8 109. 7 5 o 107.5 105. 1 Color, N. P. A. No 5- 5+ 4% 4- 4- 5- 4+ m 5 5+ 6% Conradson carbon residue, per cent 1.49 1. 41 1. 42 1.11 0.97 1. 43 1.09 1. 47 2. 24

Tower A overhead:

Recovered per cent of charge 40.0 44.0 38. 9 44.2 49. 3 26. 4 28. 3 55. 3 28. 7 35.1 Gravity, deg. Be 27. 8 27. 7 v 28. 2 28. 0 27. 9 28. 2 27. 3 28. 1 27. 3 27. 4 Flash, deg. F. 500 495 455 480 485 500 520 365 515 515 Fire, deg. F 575 575 545 570 575 575 605 570 605 600 Viscosity, S. U. 210 F 67. 92 68. 75 58. 67 64. 26 64. 5 63. 68 73. 72 61. 75 75. 59 71. 74 Viscosity index" 98. 4 99. 6. 103. 2 99. 2 101. 3 98. 4 100. 7 106. 9 98. 6 97. 4

Tower B overhead:

Recovered per cent of charge 8.0 15. 4 9. 7 16.5 21. 3 8. 4 17.6 17. 7 29. 3 9. 6 Gravity, deg. B 27.7 27. 8 28. 1 28.1 28. 3 27. 9 27. 8 28. 6 27. 7 27. 8 Flash, deg. F... 390 365 365 375 410 410 220 400 410 Fire, deg. F 495 435 430 445 460 495 400 495 485 Viscosity, S. U. 210 F" 57. 02 44. 3 44. 37 44. 1 44. 66 54. 01 41. 85 55. 69 50. 06 Viscosity index 102- 7 98. 7 102. 0 108. 4 96. 0 104. 6 111. 6 103. 6 99. 7

Tower C. overhead: Recovered per cent of charge 3 8 g 7. 9 24. 0 3 Gravity, deg. B N Q a! 32.1 32. 9 Flash, deg. g E i Q E 220 Q a a Fire, deg. F co on a: pa o 255 pm 210 pa n Condensate:

Recovered per cent of charge 22.0 19 8 18. 8 25.1 25 8 6 5 23. 9 Gaso. 18.3 13.1 Gravity, deg. B 35. 3 37 6 38. 1 40. 0 40 2 46 3 38. 6 56. 8 37. 3 37. 1

Gasoline separately heated and charged to base of reaction chamber in this test.

Test designation T W 104 101 103 107 108 G. E G. H. G.I

Acid activated clay, lbs. per gal Bauxite, lbs., per gal 87% com] cuprous oxide, gms. ea. gaL Oil and chem., chg. rate, gal. per hr Gasoline chg. rate, gal. per hr Furnace outlet temp., deg. F. (av.) Reaction chamber base temp., deg. F. Steam, per cent of oil charged Bottoms:

Gravity, deg. B5 242 n 25.8 25.5 25.4 25.9 25.9 25.5 25.2 25.5

Flash, deg. 535 .25 570 580 580 550 570 500 505 505 Fire, deg. F 710 5,53 550 570 555 535 555 575 590 590 Viscosity, s. U. 210 259.5 ugg 152.5 179.3 175.2 137.1 157.5 221 244.4 227 Viscosity index 101.7 555. 104.3 104.9 103.4 104.8 105.2 105.0 108.7 105.5

Color, N. P. A. No Green BB 5-- 5- 5+ 5- 4 4%4- 5 5- Conradson carbon residue, per cent 4. 1.58 1.53 1. 76' 1.42 1.45 1.65 1.71 1.63

Tower A overhead:

Recovered per cent of charge 32.0 40.2 29.7 38.9 32.3 14.2 20.0 23.5 47.7 42.2

Gravity, deg. B 25.8 27.5 28.3 28.0 28.1 23.4 28.4 27.5 27.5 27.8

Flash, deg. 520 505 485 .490 485 475 505 525 505 515 Fire, deg. F 510 595 555 575 555 540 580 515 5 590 500 Viscosity, s. U.@210F 78.4 70.59 50.5 54.2 50.5 57.3 57.4 75.0 71.2 72.08

Viscosity index 95.4 103.7 98.3 100.1 100.5 99.5 102.4 98.5 99.1 99.7

Tower B overhead:

Recovered percent'of charge 27.8 28.3 4.2 7.5 3,1 2.9 7.0 12.8 7.0 9.6

Gravity, deg. B5 27.8 27.7 27.7 27.8 27.8 27.8 28.3 28.2 27.9 27.9

Flash, deg. F... 415 390 415 350 355 410 440 415 420 410 Fire, deg. F 505 475 470 420 430 455 505 515 500 495 Viscosity, s. r 55.8 52.29 45.08 41.2 41.4 45. 37 49.5 53.4 49.5 49.1

Viscosity index 100.3 103.2 95.4 90.8 97.2 96.2 102.6 100.4 98.4 100.6

' Tower 0. overhead: 8 E

Recovered per cent of charge g g 5.7 5.6 3.7 7.9 6. 12.2 10.2 3.8

Gravity, deg. B 5 =1 31.0 32.0 31.0 31.4 29.1 33.1 32.3 32.9

Flash, deg. F E; Q 235 210 250 225 250 85 110 115 Fire, deg. F to to 270 250 290 270 320 100 145 145 Condensate: V

Recovered per cent of charge 13.4 22.5 6.3 6.0 5.3 6.4 10.5 Gaso. Gaso. Gaso- Gravity, deg. B 39.7 37.8 44.5 45.1 44.8 44.2 40.8 60.8 52.7 53.2

Impure.

In the above two section table Bottoms refers charge rate. During operation a liquid level of to the filtered oil recovered from the material approximately 7' was maintained in the reaction extracted from the base of the reaction chamber; tower, although this level was varied at difierent Tower A overhead, to the material withdrawn times. from the cooler attached to the first overhead The quantities of clay used per gallon of oil collection chamber; Tower B overhead, to the 40 charged in these tests varied from /2 pound to material similarly Withdrawn from the second 1 /4 p unds. ut le er n greater am unt n overhead collection chamber; Tower C overbe used depending upon the oil treated and rehead, to material from the third chamber; and sults desired. Itwas discovered that one P nd Condensate, to the material withdrawn from was close to the optimum for this 011. The nec-. the condenser receiver. In some cases tower C essary quantity of clay required is less usually was bypassed, in which case the proper notation than 25% of the weight of'the oil being treated. was made. The difierence between the Furnace ysfrom different sources or methods f repoutlet temperature and th Reaction chamber aration vary markedly in their efiectiveness. The base temperature, is the temperature range exnecessary q n ity of a clay for any iven il is isting in the oil and clay being treated. Steam, determined readily by experimentation, taking percent of oil charged me ns v l of wat nto consideration the quantity of vaporized main percent referred to the volume of the oil terial desired, quality and quantity of residual charged, changed into steam and fed into the p oducts desired, a d temperature d t e'as base of the reaction chamber. The various test well s other governing ctors involved. Q ite designations refer to those common in the induswide variation in results can be obtained t a try. In test Q no flashing steam was used except iven quantity of acid activated c ay y varying that in the clay. time of contact and temperature. .The transfer In an example of the operation of a unit in ne e p atu is egarded to be of prima accordance with this invention, a mixture of acid p nce. a soa g ti and temperature activated ay a d il was arged throu h the secondary importance. The transfer line temheater and there heated to the desired temperatures varied from 800-879 F. insofar as the perature. This mixture was discharged into the data herewith is concerned. The temperatures reaction tower maintained at substantially atto be used must be determined experimentally mospheric pressure. At the same time, steam for different oils and end results and are usually from the steam generator, in a Volume ratio relalower than t e above e for naphthenic 01 tive to the 011 charge, was introduced into the The catalyst used in he x p for which bottom of the reaction tower. The towers, predata is iven in the tables herein, consisted of viously, had been brought to the desired tem- Super Filtrol (sulfuric acid activated clay). perature by the injection of superheated steam. WF banXite and hydrochloric acid activated The charging of steam to the towers was conclays were used, but it was found in the work tinued until the unit was on stream. When .the w1th bauxite that this materia1 has too high a; unit was on stream the steam at the bottoms of specific g i y. to be readily pumped through a towers Nos. 2, 3, and 4 were, generally speaking, pipe still without continuous risk of clogging at cut on, and the charge of oil, clay and steam in some point in the apparatus and it was found the reaction vessel wasmaintained at the desired necessary to use it in conjunction with Super Filtrol. Where bauxite was used with Super Filtrol, this is indicated on the table. None of the work on the hydrochloric acid clays is reported in the tables included herein, this work having been done at an earlier time. The German Tonsil clay was found to be more effective than Super Filtrol on a dry basis. Work was also done with four samples of hydrochloric acid activated clays manufactured by an American company and normally used in the decolorization of fatty oils. In this work it was found that one of these clays which was least eifective for the treatment of fatty oil was most effective from the standpoint of the process. that the greater efiiciency of the Tonsil clay was traceable to the presence of impurities in the clay which serve to act as desulphurizing agents and thereby reduce the normal clay requirements of the reaction. In connection with this, it was observed that the clay requirements of th process can be materially reduced by incorporating in the reaction mixture a small proportion of any one of the large group of metallic compounds which form stable compounds with sulphur or other impurities. The quantity of desulphuriz-. ing metal used appears to be quite critical. This is particularly so in the case of copper, and the quantity used must be controlled within narrow limits in order to obtain maximum efficiency and effectiveness.

Synthetic crudes of these three tests were made, filtered and vacuum stilled in the labora. tory to yield the results shown on the tables included herein.

It mi ht be mentioned herethat for the purpose of separating spent catalyst from the oil,

the mixture of oil and spent catalyst was filtered through a plate and frame filter press although a y suitable method may be used.

A consideration of the results obtained indicates that two primary effects take place, namely, degradation and volatilization of unstable components, and a chemical alteration and increased stabilization of stable components, probably by a reaction such as cyclization or hydrogenation. Thus, among others, two important refining improvements result:

1. Products having both improved viscosity index. and improved physical characteristics are produced.

. 2 The, p oduction of large quantities, of lightbodied lubricants of high quality from less useful heavy-bodied oils becomes feasible, together with the production of residual heavy-bodied oils which hav an extremely high quality.

Insofar as known, no other means of accomplishing these results are available. In making this statement, it is recognized that the results obtained by the hydrogenation of. lubricating oils might be cited as a qualification.

The process is equally applicable to paraffin base, naphthene base, and mixed base oils. The effectiveness, when considered in the light of actual improvement, say, in viscosity index, is greater in the case of the naphthene base oils because there the chances of improving viscosity index are greater. In this connection, som of the work on straight zero viscosity index naphthene base oils resulted in a material with a viscosity index of about 40 to 44. On furfural refined naphthem'c oil having an initial viscosity index of 63, a carbon residue of 0.09%, a sulphur of 0.22% and a No. 3 color, with a purplish bloom, the application of the process resulted in a product having a viscosity index of 78, a carbon This indicates residue of 0.08%, a sulphur of 0.12% and a 1% color, with a yellow-green bloom. These tests do not represent the feasible upper limits obtainable with this improved process, but they in.v dicate the practicability of the process.

The examples explained above lead one to conclude that the best possible oils for internal combustion engines can be made by means of the application of thi process to naphthenic oils, because the low pour and low carbon tests are retained, While high viscosity index, high flash and stability not originally present are produced in the oil. The foregoing remarks are also applicable to mixed base oils which can be readily converted into high-grade products by the application of the process.

Residual oils resulting from the high temperature treatment of petroleum, petroleum products, or other hydrocarbon materials, usually have a foul, obnoxious odor, and are unstable. Treatment by the process herein disclosed eliminates most of these objectionable characteristics, but it was discovered that certain residual oils were not deodorized sufliciently by this means to be marketable, with economically feasible quantities of acid activated clay. Experimentation led to the discovery that certain impurities existing in hydrocarbon materials, probably forms of oxygen, sulfur, halogen, nitrogen, or other impurity, act as clay poisons, hence if a method could be devised for neutralizing or eliminating these products, marked economies in clay quantities required could be effected.

Investigation of the impurity problem using an Onondaga crude oil as the working agent, led to the discovery that certain metals, preferably in the form of compounds, including metallic salts, when used in connection with acid activated clay at temperatures substantially above 400 F. enabled the elimination of much of the undesirable matter from the residual oil, the undesired materials evolving with the distillate or being removed with the clay. In some cases temperatures above 740 F. were used. Among the impurities evolved with different metallic compounds or salts used in this connection were sulfur flowers, sulfur di-. oxide gas, hydrogen sulfide, ammonia gas, amines, nitrogen oxide, alcohols and quantities of unidentified, rank smelling, choking, gaseous mate.- rials and small amounts of unidentified white and pink-white solids. Further work with solvent refined oils led to the detection of odors of nitrobenzene, furfural and phenol in the vapors dis.- tilled off of various oils.

With reference to the common heavy metals usually in the form of oxides or salts, copper,

zinc, nickel, and iron gave excellent color results in acid activated clay treatments of Onondaga crude oil; all of the heavy metals tested, including lead, manganese, and chromium as well, asv

copper, nickel, zinc, and iron produced odor improvement. As a check on other oils, copper oxide was tried with excellent results on a wide variety of oils, both paraffinic, mixed base and asphaltic or so-called-naphthenic oils, showing that the process is applicable generally, and permitting the choice of the metal best fitting the particular oil being investigated. In several cases, mixtures of metals were-used efiectivelyto secure the beneficial effects resulting from the combination.

Because of the wide choice of metal compounds and salts available, and the fact that materials.

remaining with the oil because of the-treatment, such as halogen compounds, phosphorus compounds, sulfur compounds, nitrogen compounds and oxygen compounds are known definitely to affect film strength and oiliness characteristics of lubricants, a wide variety of copper compounds Was used with the clay on Onondaga crude oil to demonstrate the effect of varying the compound or salt used. Onondaga crude oil gives a negative chlorin indication by means of the commonly used flame test with hot copper wire, showing virtual absence of chlorine in the crude oil itself; when treated with cuprous chloride in connection with acid activated clay, among other substances, large amounts of hydrochloric acid gas were evolved, but the filtered residual oil still gave a negative chlorine test by means of the same copper wire flame test; when treated with cupric chloride, however, in addition to the large amounts of hydrochloric acid gas evolved, the liltered residual oil gave a positive chlorine test, indicating chlorine remaining in the oil; in neither of the latter cases were flowers of sulfur condensed in the condenser tube but a heavy yellow, oily substance condensing in the tube was noticed in both cases.

Copper sulfate used in a similar manner showed heavy flowers of sulfur deposits in the condenser tube, and heavy evolution of sulfur dioxide gas,

as well as other impurities. With cupric acetate, acetic acid fumes Without deposit of flowers of sulfur in the condenser tube were noted; with cupric phosphate the fume was led through water before examination, nevertheless heavy deposits of flowers of sulfur were noted in the condenser tube, and hydrogen sulfide was noticed in the fume bath; with cupric chromate, heavy flowers of sulfur deposits were noted in the condenser tube, together with heavy evolution of fumes, and a relativelyplean appearing distillate; cupric hydroxide, cuprous oxide, cupric oxide, cupric carbonate, cupric hydroxide-carbonate, reactive copper. silicate and cupric-nickelous hydroxide, each in combination with acid activated clay permitted evolution of flowers of sulfur and yielded satisfactory residual products. In connection with nitrates, nitrogen oxide as well as both ammonia gas and amines were detected among the impurities evolved. Combinations of metallic salts have been used and may be used if desired.

It is quite within the scope of this disclosure to use combinations either of metals, metals and salts, or salts of metals, in connection with acid activated clay or clays, depending upon results desired. Inclusion of a portion of the acidic radical in the residual oil also may decide the choice.

In preventing the poisoning of the clay by the impurities of the hydrocarbon under treatment, the metals in pure metallic subdivided form do not appear to be as satisfactory in action as are the compounds of the metals, and particularly the salts of the metals.

It will be understood that various changes in the details which have been herein described in order to explain the nature of the invention, may be made by those skilled in the art, within the principle and scope of the invention, as expressed in the appended claims.

I claim:

l. In the conversion, of a naphthenic petroleum oil, to obtain a relatively high yield of light-bodied lubricating components of superior physical characteristics, such as a high viscosity index, high flash and stability, the improved method which comprises mixing said oil, while at a temperature below its natural cracking temperature, with unspent, acid-activated clay to provide a pumpable mixture in which the clay is suspended in the oil and amounts to approximately between one-half pound and one and onequarter pounds per gallon of oil, passing said mixture as a stream in liquid phase and upwardly through an ascending heating passage and then into a reaction chamber, incorporating water in the mixture before it completes its ascent in said passage equal to approximately per cent of the oil, heating the mixture while moving in said passage approximately to cracking temperature below approximately 900 degrees F., flashing the heated mixture with a vapor in said chamber at cracking temperature, separating the overhead vapors from the bottoms con taining the clay, and condensing the overhead vapors.

2. In the conversion of a naphthenic petroleum oil, to obtain a relatively high yield of lightbodied lubricating components of superior physical characteristics, such as a high viscosity index, high flash and stability, the improved meth; od which comprises mixing said oil, while at a temperature below its natural cracking temperature, with unspent, acid-activated clay to provide a pumpable mixture in which the clay issuspended in the oil and amounts to approxi mately between one-half pound and one and onequarter pounds per gallon of oil, passing said mixture as a stream in liquid phase and upwardly through an ascending heating passage and then into a reaction chamber, incorporating in the mixture before it completes its ascent in said passage, a flashing agent in liquid phase which vaporizes at a temperature lower than that to which the mixture is heated before it reaches the top of said ascending passage, equal to approximately 95 per cent of the oil, heating the mixture while movin in said passage approximately to cracking temperature below approximately 900 degrees F., flashing the heated mixture with a vapor in said chamber at cracking temperature, separating the overhead vapors from the bottoms containing the clay, and condensing the overhead vapors.

3. In the conversion of a naphthenic petroleum oil, to obtain a relatively high yield of lightbodied lubricating components of superior physical characteristics, such as a high viscosity index, high 7 flash and stability, .the improved method which comprises mixing said oil, While at a temperature below its natural cracking temperature, with unspent, acid-activated clay and a finely divided agent containing a metal to provide a pumpable mixture in which the clay and finely divided agent are suspended in the oil an amount to approximately between one-half pound and one and one-quarter pounds per gallon of oil, passing said mixture as a stream in liquid phase and upwardly through an ascending heating passage, and then into a reaction chamber, incorporating water in the mixture before it completes its ascent in said passage equal to approximately 95 per cent of the oil, heating the mixture while moving in said passage approximately to cracking temperature below approximately 900 degrees F., flashing the heated mixture with a Vapor in said chamber at cracking temperature, separating the overhead vapors from the bottoms containing the clay and finely divided agent, and condensing the overhead vapors.

4. In the conversion of a petroleum oil, to obtain a relatively high yield of light-bodied lubrieating components with relatively high viscosity index, high flash and stability, the improved method which comprises mixing said oil while at a temperature below its natural cracking temperature with unspent, acid-activated clay, to provide a pumpable mixture in which the clay is suspended in the oil and amounts to at least approximately one-half pound of clay per gallon of oil, passing said mixture as a stream in liquid phase upwardly in an ascending heating passage, heating the stream in said passage to the desired conversion temperature and below approximately 900 degree F., incorporating a readily volatilizable liquid in the mixture of said stream before the stream completes its ascent and before the temperature is raised to the maximum extent, flashing the heated mixture of said stream after it reaches said desired conversion temperature to create vapors, separating the vapors from the bottoms containing the clay, and condensing the vapors.

5. In the conversion of a naphthenic petrobum oil, to obtain a relatively high yield of lightbodied lubricating components with relatively high viscosity index, high flash and stability, the improved method which'comprises mixing said oil, while at a temperature below its natural cracking temperature, with unspent, acid-activated clay to provide a pumpable mixture in which the clay is suspended in the oil and amounts to at least approximately one-half pound of clay for each gallon of oil, passing said mixture as a stream in liquid phase upwardly through an ascending passage and then into a reaction chamber, incorporating water in the mixture of said stream before the stream completes its ascent in said passage, heating the mixture moving in said passage approximately to a desired conversion temperature and below approximately 900 degrees F., flashing the heated mixture in said chamber to create vapors, separating the overhead vapors from the bottoms containing the clay, and condensing the overhead vapors.

6. In the conversion of a petroleum oil, to obtain a relatively high yield of light-bodied lubricating components having a relatively high viscosity index, high flash and stability, the improved method which comprises mixing said oil while at a temperature below its natural; cracking temperature with unspent, acid-activated clay to provide a pumpable mixture in which the clay amounts to at least approximately one-half pound per gallon of oil, passing said mixture as a stream in liquid phase upwardly in'a confined passage and then into a reaction chamber, incorporating in said stream before it completes its ascent in said passage a flashing agent in liquid phase, which vaporizes at a temperature below that to which the stream is heated before it completes it ascent in said passage, heating the mixture moving in said passage to a desired conversion temperature less than approximately 900 degrees F., flashing the heated mixture in said chamber to create vapors, separating said vapors from the bottoms containing the clay, and condensing the overhead vapors.

7. In the conversion of a petroleum oil, to obtain a relatively high yield of light-bodied lubricating components of superior physical characteristics, such as a high viscosity index, high flash and stability, the improved method which comprises mixing said oil, while at a temperature below its natural cracking temperature, with unspent, acid-activated clay-to provide a pumpable mixture in which the clay is suspended in the oil and amounts to approximately between one-half pound and one and one-quarter pounds per gallon of oil, passing said mixture as a stream in liquid phase and upwardly through an ascending heating passage and then into a reaction chamber, incorporating water in the mixture before it completes its ascent in said passage, heating the mixture while moving in said passage approximately to cracking temperature below approximately 900 degrees F., flashing the heated mixture in said chamber at cracking temperature, separating the overhead vapors from the bottoms containing the clay, and condensing the overhead vapors.

8. In the conversion of a petroleum oil, to obtain a relatively high yield of light-bodied lubricating components with relatively high viscosity index, high flash and stability, the improved method which comprises mixing said oil while at a temperature below its natural cracking temperature with unspent, acid-activated clay, to provide a pumpable mixture in which the clay is suspended in the oil, passing said mixture as a stream in liquid phase upwardly in an ascending heating passage, heating the stream in said passage to the desired conversion temperature and below approximately 900 degrees F., incorporating a readily volatilizable liquid in the mixture of said stream before the stream completes its ascent and before the temperature is raised to the maximum extent, flashing the heated mixture of said stream after it reaches said desired conversion temperature to create vapors, separating the vapors from the bottoms containing th clay, and condensing the vapors.

9. In the conversion of a naphthenic petroleum oil, to obtain a relatively high yield of lightbodied lubricating components with relatively high viscosity index, high flash and stability, the improved method which comprises mixing said oil, while at a temperature below its natural cracking temperature, with unspent, acid-activated clay to provide a pumpable mixture in which the clay is suspended in the oil, passing said mixture as a stream in liquid phase upwardly through an ascending passage and then into a. reaction chamber, incorporating water in the mixture of said stream before the stream completes its ascent in said passage, heating the mixture moving in said passage approximately to a desired conversion temperature and below approximately 900 degrees F., flashing the heated mixture in said chamber to create vapors, separating the overhead vapors from the bottoms containing the clay, and condensing the overhead vapors.

10. In the conversion of a petroleum oil, to obtain a relatively high yield of light-bodied lubricating components with relatively high viscosity index, high flash and stability, the improved method which comprises mixing said 011 while at a temperature below its natural cracking temperature with unspent, acid-activated clay and a metallic oxide, to provide a pumpable mixture in which the clay is suspended in the oil and amounts to at least approximately one-half pound of clay per gallon of oil, passing said mixture as a stream in liquid phase upwardly in an ascending heating passage, heating the stream in said passage to the desired conversion temperature and below approximately 900 degrees F., incorporating a readily volatilizable liquid in the mixture of said stream before the stream completes itsascent and before the temperature is raised to the maximum extent, flashing the heated mixture of said stream after it reaches said desired conversion temperature to create vapors, separating the vapors from the bottoms containing the clay, and condensing the vapors.

11. In the conversion of a petroleum oil, to obtain a relatively high yield of light-bodied lubricating components of superior physical characteristics, such as a high viscosity index, high flash and stability, the improved method which comprises mixing said oil, while at a temperature below its natural cracking temperature, with unspent, acid-activated clay' to provide a pumpable mixture in which the clay is suspended in the oil and amounts to approximately between one-half pound and one and one-quarter pounds per gallon of oil, passing said mixture as a stream in liquid phase and upwardly through an ascending heating passage and then into a reaction chamber, incorporating water in the mixture before it completes its ascent in said passage equal to approximately 95 per cent of the oil, heating the mixture while moving in said passage approximately to cracking temperature below approximately 900 degrees F., flashing the heated mixture with a vapor in said chamber at cracking temperature, separating the overhead vapors from the bottoms containing the clay, and condensing the overhead vapors.

12. In the conversion of a petroleum oil, to obtain a relatively high yield of light-bodied lubricating components with relatively high viscosity index, high flash and stability, the improved method which comprises mixing said oil while at a temperature below its natural cracking temperature with unspent, acid-activated clay, to provide a pumpable mixture in which the clay is suspended in the oil, passing said mixture as a stream in liquid phase upwardly in a heating passage, heating the stream in said passage to the desired conversion temperature and below approximately 900 degrees F., incorporating a readily volatilizable liquid in the mixture of said stream before the stream completes its ascent and before the temperature is raised to the maximum extent, flashing the heated mixture of said stream with steam in an amount which before conversion from water to steam was at least percent by volume of the oil, after it reaches said desired conversion temperature to create vapors, separating the vapors from the bottoms containing the clay, and condensing the vapors.

WILLIAM ALVAH SMITH.