US2057402A - Destructive hydrogenation of organic materials - Google Patents

Description

joct. 13, 1936; H TROPSCH 2,057,402

DESTRUCTIVE HYDROGENATION OF ORGANIC MATERIALS f Filed July 1s, 1954 carbon products.

- In a more specic aspect the invention is con-` i f Y Patented 13, 19236 PATENT. ori-lcs f RGANIC MATERIALS Hans Trpsch, Chicago, Ill., assigner to Universal Oil Products Company, Chicago, Ill., a corpora 4tion of Delaware g Application July 13, 1 934, serial No. '134,395 j 40mm. y(ci. 19653) n This inventionrelates more particularly to the treatment of hydrocarbon materials for the prol duction therefrom of high yields of good anti-v knock .value motor fuel and other refined vhydro-i cerned with a process in which Anascent active hydrogenplays an important role in reactions of decomposition and recomposition among various classes of hydrocarbons during theiroh'eat treatment, resulting inthe production of higher yields of good quality products than those resulting from i ordinary pyrolytic processes. f The process may be employed to treat a 4con-r siderable variety of naturally occurring and synthetic hydrocarbon mixtures such as, for example, petroleum and its fractions resulting from ordilnary or destructive distillation, and also coal and A closely related minerals such as lignite and their primary or secondary distillation products, in-

cluding coal tar, lignite tar, and aromatic dls-v tillates. Briefly stated, the process of the invention can be applied generallyto the treatment' or improvement of hydrocarbon or hydrocarbog5 naceous materials from any source.

Decomposition by heatwhich has been designated as cracking or pyrolysis, is practiced extensively on heavy hydrocarbon materials with the object of producing maximum yields'of low boiling hydrocarbon mixes which yhave 'sufficient volatility and properl chemical characteristics (or use as internal combustion engine fuels. More extensive cracking is practiced with the object oi producing fuel gas and coke. i

In cracking any heavy hydrocarbon mixture, the ultimate yield of desired products is definitelyI limited bythe amount of originally combined' hydrogen in the stock treated since the desired lower boiling materials have a higher hydrogen-A carbon ratio than theoriginal'charge and owing to thishydrogen transfer the residues have a much lower ratio, particularly if operations are C conducted until heavy liquid residues or solid coke is formed.

Pyrolyticprocesses are also insufficient in re- 4 spect to the production of low boiling hytirocllr bon. liquids in that a certainamount of hydrogen released from its original combination in the primary decomposition reactions does not react'furtherand appears in the molecular and unreactive state in the gaseous products. n

' Various processes employing extraneous hydrogen have been .developed tol overcome the more obvious disadvantages inherent in ordinary cracking processes such as the limits o t 'yield of ,of, hydrogenation proc esses,\it had been known .for a long time that additionl hydrogen to un saturated compounds could readily accom- 5 plished by employing molecular hydrogen in the presence of certain metallic catalysts, notably freshly reduced nickel which has a high eillciency in eiecting the addition of hydrogen to unsaturated compounds such as oleic acid to make' l0 stearic acid and also to hydrocarbons characterized by either chain or ring unsaturation. These more active catalysts typified by nickel are at the same time extremely sensitive Ito poisoning influences due to the presence of sulphur, arsenic. etc., l5 in reaction materials, and are also gradually depreciated by the deposition oi small amounts of carbonwhich decrease their total eiective catalytic surface.

Previously known types of active catalysts were 20 found to have substantially no practical value Y when attempts were made to employ them in hydrogenating coal and other solid mineral hydrocarbons and in cracking and hydrogenating peltried which operate without catalysts under very high hydrogen pressure of the order of from 2000 to 5000 pounds per square inch and othervproc- 30 esses have soughtto treat mixtures of solid and liquid hydrocarbons using catalytic materials of lesser activity but with greater resistance to poisoning' inuences such as, for example, 'the oxidesand sulphides of the metals of, the 6th group voi 35 the periodic table including chromium, molybde.- nu'm and tungsten with and without promoting substances. 'I'he commercial technique ofthese processes has been developed to a considerable ex-y tent. The present process is in a sense a develop 40 ment along the latter line. although it is in another sense a distinct departur therefrom.

In one specific embodiment the present invention lcomprises destructivelyhydrogenating hy- `drocarbonaceous materials'using hydrogen gen- 45 erated in situ 'by the interaction of carbon monoxide and waterin the presence of catalytic materials comprising the oxidesv of the alkaline earth metals, e, g. magnesium` and calcium or mixtures of the same. 50

` -The term destructive hydrogenation" is used in the present, connection'to include the sum total of reactions between added hydrogen and the primary decomposition products of hydrocarbonaceous materials produced at elevated 'temperatures f tion actions which correspond merely to the adv dition"` of hydrogen to unsaturated linkages to prokducelthe corresponding saturated compounds. In destructive hydrogenation reactions unsaturated compounds both of a chain and a cyclic character may appear in the inal products depending upon the conditions of time, temperature. pressure and hydrogen concentration employed. Thus it is possible to produce high yields of good anti-knock gasoline by destructively hydrogenating heavy hydrocarbon material while suitably correlating the physical and chemical factors involved.

Under the preferred conditions of reaction in the present process nascent hydrogen is liberated in accordance with the following equation:

. coq-mo a vcortili-:I+ This reaction and the subsequent reactions in which the hydrogen enters into .combination are both catalyzed and further promoted by the fact that the preferred mixture of oxides reacts with the carbon dioxide formed, removing one of the v products of the hydrogen-producing reaction and causing it to continue in the desired direction as long as the reacting constituents are present. The

`carbon dioxide reacts most readily with calcium oxide although some interaction gradually occurs to remove the magnesium oxide 'also from the sphere o f the reaction.

The broad principles of the present process may be successfully applied to the destructive hydrogenation oi hydrocarbonaceous materials in numerous ways involving different types of plant equipment of both a. batch and a continuous character, although the latter type practically always used in commercial work. Ina batch operation, for example, an intimate mixture of oil or oiland coal with the nely divided oxides obtained, for example, by calcinlng dolomite is emulsied with water and added to a pressure vessel,the vessel is heated to an optimum temperature within a range which will be later specified and carbon monoxide is introduced to bring about the desired Feactions. As an alternative mode of operation carbon monoxide and steam may Abe added gradually ,in suitable proportions to the dry mixof hydrocarbons and oxides in thebomb, during mechanical agitation.

' Some preheating ofthe gases introduced 4may be necessary although the reactions are-in general l exothermic and tend to maintain the desired tem-4 perature. It'is not' necessary to use pure car bon monoxide in the process since the catalysts are not sensitive to ordinary poisoning influences. Water gas and other carbon monoxide-containing gases may be used, although the greater eiiiciericy will result when gases containing relatively higher percentages of thisigas are employed.

To illustrate 'some of the details of a practical continuous operation of the proce the attached drawing has been provided which shows inside elevation by the use of conventional gures an -arrangement of interconnected elements in which it may be conducted. The plant shown has a certain degree of ilexib'ility but it is not to be inferred that the scope of the invention is limited by the arrangement or proportloning oi the drawing since the parts are not drawn toscale and many modiiications are possible within` the province oi' the' invention.

Referring to the drawing a mixture oi uid hydrocarbon material and finely divided calcined of operation is' in a supply tank I and maintained in suspension by mechanical stirring devices or outside circulating pumps although neither of these two commonly used expedients is shown in the drawing. In operating with coal the lines are suspended in oil along with the oxide catalysts. 2

vindicates a hatch through which thesolid ingredients of the primary mix may be introduced into the tank depending upon the nature of the materials undergoing treatment and in other alternative modes of operation, a part or all of the water required for theereaction of hydrogen production may also be emulsiiled with and maintained in suspension in the fluid menstruum along with the suspended solids.

The mixture or slurry of charging material. is then taken through line 3 containing control valve 4 by charging pump 5 and brought to the required temperature and pressure for the subsequent reactions, passing through line 6 containing control valve 'I through a tubular heating element 8 disposed to receive heat from a furnace 8. Either carbon monoxide or water or steam required for the hydrogenation reactions may be introduced at this lpoint in whole or in part. suction on a supply of carbon monoxide (or a gas mixture containing a substantial percentage thereof) from a source not shown through a line IIJ containing control valve II and discharging through a line I3 containing control valve I4 either into line I5 containing control valve I8 and into line 6.or throughy line I1 containing control valve I8 into line 28 containing control valve 29 and leading from the heating element to subsequent reaction and settling chambers.

2| indicates a water pump taking suction through line I9 containing control valve 20 and discharging through line 22 containing control valve 23 and branching into line containing control valve 25 leading to'lirie 6 or line 26 containing controifvalve 21 ieading to iine za. rn lieu of' water injection at these points high pressure steam, either saturated or superheated may be added in place of water. It is comprised within the scope of the invention and may be of some .-tion thus far given thatlvvater` or steam may be added either at the entrance or the exit of the heating element as well as in thev primary mix.- As a rule itis preferable also to add the carbon monoxide at the same points and in most vinstances the majority is added in transfer line 2l lust prior to the entrance of the heated materials to the reaction and settling chambers. Y Two reaction chambers have been shown in parallel arrangement although any number may l be employed in this manner vso that the precipitated and Spent solid catalytic material may be removed lfrom some chambers while they are ac- -cumulatlng in others in the course ot the reactions. 'I'hus the drawing shows line 2l branching into line 2l containing control valve 3| and leading to reaction chamber $2 and branch line.

Il' containing control valve II' and leading to reaction chamber 32'. Each reaction chamber is 'provided with upper and lowes' removable manhole covers ior the injectionvof fresh or r o val bi' spent catalytic material since ii' desired the amount of oxides added to the hydrocarbon charge composition terial,.partly or wholly carbonated and possiblel may accumulate in the reaction chambers will bev ldetermined by the character of the charging material and the conditions and objects of the operation. For example, if a mixture of coal and oil is treated to producev increased yields of lubrieating or intermediate fractions, a large amount of relatively heavy 'liquid may accumulate in the.

reaction chambers and be withdrawn therefrom for subsequent fractionation or reduction. At other times the products from the reaction cham' ber comprising both vaporsand liquids may be continuously withdrawn in a manner to be 'presently described l.

The greater portion of the reactions of destructive hydrogenation occur in the reaction and settling chambers according to the equation of hydrogen production already given and the various complicated hydrocarbon decomposition and rereactions. The solid catalytic masomewhat carbonized will gradually accumulate in a reaction chamber which iscut out of the system when the reaction space becomes insum cient, at whichtime other emptychambers are cui; in. v j

To regenerate the partly spent solids accumulating in the reaction chambers they may be 4separated from adhering oilA and tar by treatment with solvents such as gasoline followed by` settlingand possibly illter pressing, after which the mixture of carbonates and oxides is calcined to I.produce a mixture containing ya higher percentage of oxides and a certain amount oflcarbon dioxide. This latter gas may be then passed over coke to reduce it to carbon monoxide Yfor .further use in the process. The details of such operations are fairly well known in commercial work and an extensive description of operating ,details is not necessary.

` and any .desired pressure up `ses The. process may employ temperatures with'- in theapproximate range of from 400 to 650 C., to, for example, several thousand pounds per square inch, e. g. 3000 pounds per square inch, i! such are found to be necessary to the efficiency of the process. Only general ranges can-be stated since a great deal will depend upon the degree vof contacto!y the reacting materials which inv turndepends upon such factors as the iineness or the solids.

and the thoroughness or mixing,

Hydrocarbon reaction. products pass from chamber 32 through. lines 3,5 containing control valves 36 lor'frorn reactlon'chamberfl' by way .of lines 35" containing control valves'lto enter header line 31 containing control valve 3B`and leading to Iractionating equipment. The relative proportions of vaporous and liquid prod ucts will depend upon the temperature' and pressure of the reaction chambers. and i! the proportion of liquid is high, the lines shown `leading from the side of the chambers at different levels may be employed tocontinuouslyremove liquid accumulations along with' the vapors removed `from the lines leaving-the top of the chambers,

theliquid-vaporseparation thenxbeing made in thesucceeding flash chamber and iractionating tower.

Products from the reactionchavmbers may en.'

3 ter a flash chamber .I0 under) somewhat reduced 'pressure and separate out heavy residual' liquids fin cases where gasoline lsdesired as themainl product of the process.. the heavy liquid being withdrawn from the .hash chamber through a line I0 containing control valve Il.' AIn case the j production of. heavier liquids is the main object of the process the flash chamber mayibeem ployed merely to volatillze light ends. f i

The vapors from v the ilash chamber pass through linel2 containing control valvej to a ilnal fractionator M, the design of which will be varied according to the products desired from the operation and which will usuallybe adapted to producev an overhead gasoline boiling range fraction when the procs is operated in connection with petroleum refining. The vaporsand ilxed gases from the iractlonator pass through a line 50 containing control `valve 5I, after which .they pass through a condenser 52 for liquefying the normally liquid components which then pass v together with uncondensed gases ythrough. line 53 containing control valve. to receiver 55pmvided with a gas release line 58 containing coniractionator 4l will usutrol valve 51 and a liquid draw line 58 containally be of the type adapted to further couver-- f sion and are taken through a line I5 containing control valve 46 to a recycling pump 41 and discharged by way of -line 48 containing control valve 49 back to combined feed line 6 and thence through the process as already described.

Owing to the wide applicability of the present processupon miscellaneous hydrocarbonaceous materials as previously enumerated, it will be apparent that a large number of examples could be recited in support of its commercial advantages. However, the following will be sufficiently illustrative to assist in describlngthe character oi 'the invention.'

A cracked -residuum resulting from the pyrolysis of 'a Mid-Continentfuel oil was used as starting material. The details of the primary crack-f ing run, which was conducted in a lmodern type of commercialcracking plant, vare given below. The A. P. I. gravity of the, fuel oil was 24.3 and it had an initial boiling point of 595 F.

. Details of cracking operation peraturei 925 1l'. Yield of ,gasoline..-.. 56%'byvolume. Yield of;:residuum 38.5%'byvolume. Cu. ft. of'v gas/bbl. voi

`charge 415 A. P. Lgravity of gasoline; 59 Initial boiling point- F. n# 5.0% over at "265 F. 90% .over at--; 3,'751". End boiling point 395 F. A. P. I. gravity of cracked residllum-- 9 B. B 0.3% Saybolt Iurol viscosity at 122 F 110 secs. C old test-.. 25 F. I. B. P .420 l". Percent over at 572 I"..s.V y 48 The `above residuum was destnictively hydro- 4' aois'mcaY reaction between carbon monoxide and steam.

For the production of 80% by volume of 400 end point gasoline from this residuum a weight consumption of A4% of hydrogen was found to be necessary and with an equimolecular mixture4 of magnesium and calcium oxides the combined weight of the two amounts to about 850 pounds per barrel of residuum, with complete absorption of the CO2 by the calcium oxide.

Instead of attempting to cause the complete conversion in one stage, about 20% gasoline was made in four successive operations b'y utilizing each time about one-fourth of the total required quantities of carbon monoxide and water and the chemically equivalent amount of combined oxides. A 'summary of the quantities of materials used in each operation per 42 gallon barrel of the cracked residuum treated is given below:

. Quantities of treating materials Water gallons 5 Carbon monoxide cu. ft-- 850 Calcium oxide pounds 125 Magnesium oxide -do 90 The combined oxides were mixed with the cracked residuum, pumped through the heating element up to a pressure of about 2000 pounds per square inch and raised to a temperature of about 850 F., the carbon monoxide and water being pumped into the transfer line prior to the admission oi the suspension of oxides in oil'to the reaction chamber.

'I'he vaporous andhydrocarbon Iliquid products from the reaction were segregated to produce gasoline `and a recycle stock, the latter being resubjected to substantially the same conditions oi treatment, and this process was repeated until the required 80% production of gasoline was obtained. Y

The'properties of the nall'y produced gasoline are given below:

Gravity A. P. I 63 Initial boiling point 100 F. over at 180 F; 50% over at 280 F. 90% over at --.7. 390 F.

End boiling point 425 F Octane number, motor method 70 The utility and practical advantages of the present process will be evident from the preceding speciilcation which discloses its details and the single instance of results obtainable by use proves its commercial possibilities. However, neither oi' the preceding sections are intended to unduly limit its scope.

I claim asl my invention: 1. A process forthe destructive hydrogenation of hydrocarbonaceous materials to increase the yield of low boiling products therefrom and to improve its characteristics by reducing the boiling range thereof and the carbon-to-hydrogen ratio which comprises subjecting the said hydrocarbonaceous materials while at elevated temperatures of from 400 to 650 C., and superatmospheric pressure up to approximately 3000 pounds per square inch to the simultaneous action of carbon monoxide and water in the presence of a mixture of calcium and magnesium oxides, the magnesium oxide being in suiilcient amount to catalyze the hydrogenation reaction and the formation of hydrogen from the carbon monoxide and water and the calcium .oxide being in suficient amount to absorb the carbon dioxide formed by the reaction of the carbon monoxide and water.

2. In the destructive hydrogenation of hydrocarbonaceous material, the improvement which comprises adding magnesium oxide and calcium oxide to the material and generating hydrogen for thelhydrogenation in situ by the reaction of carbon monoxide and water within the mixture, the vmagnesium oxide being in suiiicient amount to catalyze the hydrogenation reaction and the formation of hydrogen from the carbon monoxide `and water and the calcium oxide being in suflicient amount to absorb the carbon dioxide formed i--by the reaction of the carbon monoxide and water.

In the destructive hydrogenation of hydrocarbonaceous material, the improvement which comprises generating hydrogen for the hydrogen- -ation in situ by the reaction of carbon monoxide and water within the'- material, the hydrogenforming reaction and the hydrogenating reaction being effected in the presence of a suilcient quantity of an equlmolecular mixture of magnesium and calcium oxides to catalyze. said reactions and to absorb the carbon dioxide formed by the firstnamed reaction.

4. In the destructive hydrogenation of hydrocarbonaceous material. the improvement which comprises generating hydrogen for the hydrogenation in situ by the reaction of carbon monoxide and water within the material, the hydrogenforming reaction and the hydrogenating reaction being effected in the presence of a suilicient quantity of calcined dolomite to catalyze' said reactions and to absorb the carbon dioxide formed by the iirst-named reaction.

' HANS TROPSCH.

Images