US1922491A - Conversion of hydrocarbons of high boiling point into those of low boiling point - Google Patents

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ugl5, 1933- A. MlTTAscH ET Al. 1,922,491

CONVERSION OF HYDROCARBONS OF HIGH BOILING POINT INTO THOSE OF LOW BOILING POINT Aug. l5, 1933. AfMrrTAscH Erm. 1,922,491 CONVERSION OF HYDROCARBONS OF HIGH BOILING y POINT INTO THOSE OF LOW BQILING POINT Patented Aug. 15, 1933 UNITED STATES.

PATENT OFFICE CONVERSION -F\ HYDROCARBONS OF HIGH BOILING POINT INTO THOSE OF LOW BOILING POINT Alwin Mittasch, Mannheim, Georg Stern, Neckargemund,v and Ernst Galle, Ludwigshafenon-the-Rhine, Germany, assignors to I. G. Farbenindustrie Aktiengesellschaft,

Frankforton-the-Main, Germanma Corporation ol' Germany Application 4March 29,

1927, Serial No. 179,391,

and-in Germany April 1, 1926 6 Claims.

In the conversion of hydrocarbon mixtures of high boiling point, such as tars, mineral oils, bitumen, asphalt, distillation products and residues thereof and the like, into liquid compounds oi.

lower boiling point, by heating, the results hitherto obtained have been considerably impaired by the deposition of carbon on the metallic surfaces present in the reaction chamber, such as iron and the like.

10- We have now found that satisfactory results may be obtained even when heated free iron is present, provided no metal capable of causing a deposition of carbon when hot is present in the hot zone. We have discovered that in this respect the metals titanium, tantalum and their alloys giverise only to very little, if any, deposition of carbon, and furnish excellent yields of benzine and the like. At the same time, and especially when they present a large supercial area, these metals exert catalytic action improving the output of a given apparatus; though other catalysts such as those of an oxd or sulnd character, may be used instead. Suitable alloys are for example manganese steels, consisting for example to an extent of 0.3 per cent of carbon and 1.3 per cent of manganese or 0.9 per cent ofv carbon and 10 per cent of manganese, or titanium steels consisting to an extent of 0.1 per cent of carbon and 0.2 per cent of titanium, or tantalum 0 steels consisting for example to an extent of 0.16 per cent of carbon and 1.05 per cent of tantalum, the remainder in all these alloys being iron.

The heating may be effected either from the outside in the usual manner, or more suitably internal heating may be effected, avoiding the use of metals and alloys giving rise to the deposition of carbon and employing the metals and alloys specied. Accordingly the heat may be supplied by means of a heating coil of a special g steel rich in manganese or titanium in which a circulation of molten masses or hot gases such as superheated steam, is maintained as the source of heat, or electrical resistance heating may be applied in the form of heating Wires, ribbons or the like, made of metals or alloys which do not give rise to the deposition of carbon, and preferably are also catalytic in' action.' In this way the whole, or the greater portion, of the heat required for the reaction can be applied through the surface of the catalytic substances themselves. Instead of coherent heating bodies, use may be made of granular resistance material, provided it does not, in any case, consist of metal capable of causing deposition of carbon. Generally speaking it is preferable that the bulk of the substances under treatment should form a coherent liquid during the reaction. The said process, may be carried out in a great variety of ways.

In the accompanying drawings Figure 1 and Figure 2 show diagrammatically vertical sections of two apparatus in which the process according to the present invention may be carried out, the invention, however, not being limited thereto. Referring to Figurel 1, A is a closed reaction vessel which is lined with any suitable material not causing deposition of carbon and into which the hydrocarbon-oil to be treated may be introduced through pipe D which latter may be shut off` by cook I. The oil is electrically heated by a ,catalytically acting wire B passing through insulating devices E1 and Ez into the said reaction Vessel. The oil is kept in motion by the stirring device C. Vapors formed during the reaction may pass through valve I-I and outlet pipe F into any suitable condenser (not shown). After the reaction is finished the converted liquid products are drawn off at the outlet G which is opened by cock K.

Figure 2 represents anapparatus in which the oil is heated by means of a hot fluid passing through a heating coil N-N' which is constructed of a material not causing deposition of carbon and spirally wound around the inner 'surface of the reaction-vessel M. Also'this vessel is lined with'a` material not causing deposition 'of carbon. The bottom of the vessel is lled with lumps of catalysts O resting on the perforated plate W. The hydrocarbon oil yof high boiling point is introduced into the reaction vessel through pipe R and may be kept in motion by the stirring device V. Cocks S and T allow of closing inlet pipe R and outlet pipe P respectively. Vapors formed during the -reaction may pass through valve'U into the outlet pipe Q.

The process according to the present invention is carried out with particular' advantage in the presence of such non-metallic catalysts as do not give rise to the deposition of carbon, as for example selenium and tellurium. 'These catalysts are hereinafter referred to as anti-carbon forming catalysts. Apart from metalloids and their compounds such catalysts may include metallic comn pounds of various kinds, for example oxygen compounds of metalsN especially oxids of the heavy metals of the third to sixth group of the periodic system and also those of iron, nickel and cobalt. In this case, a powerful catalytic action (varying with the nature of the catalyst) takes place, without oxygen compounds, if used, being reduced to the metallic state and without any troublesome deposition of carbon, an abundant yield of hydrocarbonsof low boiling point, with the characteristics of benzine,.being produced. g

The liquids may be caused to flow over lumps of catalytic substances in solid form, as for example in a column, at a suitable temperature ranging between about 300 and 450 C.

Accordingto this manner of working, the heating is preferably regulated in accordance with the rate of decomposition of the original mate. rials, so that, mainly, only such products will distill over as boil below the limit of boiling points desired for the time being. The operation may be conducted for example by providing the reaction vessel with a refiux condenser its temperature being adjusted so that only the desired products can pass over.

When a column is employed, the working temperature and rate of ow maintained are preferably such that the conversion products boiling below a predetermined limit pass away in the form of vapor at the upper end.

The process herein described may be carried on at ordinary, re'duced or increased pressure, and inert gases may also be passed through the apparatus during the process. The process may be rendered continuous, by constantly replenshing the amount of oil distilled off, the highly viscous still residue being generally removed only at intervals. Instead of being condensed at once, the vapors which pass over may also subsequently be subjected to a separate catalytic treatment.

Coal may also be transformed according to the present process into valuable liquid products, a`

preferable in this casepto use dissolved or, iinelyA pulverized catalysts.A

The resulting products may be used directly for example as motor fuel, or may be further treated in a variety of ways, as for example by fractionation, hydrogenation, chlorination, oxidation or by other ways.

The resulting liquid products may also be treated, either as such, or preferably after separation of the readily volatile constituents (suitable for direct employment as petroleum spirit or benzine), at an elevated temperature and preferably under increased pressures, with hydrogen, or gases furnishing same, with or without the presence of catalysts. In this manner practically the whole amount of the hydrocarbon mixture of high boiling point treated, may be recovered in the form of products of lower boiling point, suitable for use as motor fuel, solvents, lubricating oil and the like.

The following example will further illustrate how the said invention may be carried into practical effect but the said invention is not limited to this example.

Example The vessel A shown in Figure l may be made of tantalum steel (6% tantalum, 14% chromium, 1.215% carbon, the rest iron). The vessel may,

, if desired, contain a catalyst, for example molybbe continuously distilled off through the outlet F as lower boiling oils, there being no disturbing deposition of coke from the residue. If the cracking is carried out in a vessel with an iron surface and containing an iron wire, more than 10% of carbon is deposited as coke in a very solid form on the walls of the vessel and on the heated wire. In the apparatus shown in Figure l as immediately described above, all of those parts of the apparatus which come into contact with the hot liquid are made of a material comprising tantalum. The above mentioned tantalum wire can be substituted with the same success by a titanium wire. The oil treated in the vessel A may be tar obtained by low -temperature distillation of brown coal and from which the constituents boiling below 200 C. have been distillled off, crude mineral oil, producer tar and the What we claim is:

l. In the conversion of hydrocarbons of high boiling point into liquid hydrocarbons of lower boiling point in the liquid phase at a temperature between about 300 and 450 C. the step which comprises heating the said materials in a space confined by a material selected from the group consisting of free titanium, tantalum and alloys of tantalum.

2. In the conversion of hydrocarbons of high boiling point into liquid hydrocarbons of lower boiling point in the liquid phase at a temperature between about 300 and 450 C. the step which comprises heating the said materials in a space confined by a material selected from the group consisting of titanium, tantalum and alloys containing at least one of these metals and in the presence of a non-metallic anti-carbon forming catalyst selected from the class consisting of selenium, tellurium, oxides of the heavy metals of the third to the sixth group of the periodic 115 system and of iron, nickel and cobalt.

3. In the conversion of hydrocarbons of high boiling point into liquid hydrocarbons of lower boiling point in the liquid phase at a temperature between about 300 and 450 C. the step which 120 comprisesheating the said materials in a vessel the hot parts of which consist of a metal selected from the group consisting of free titanium and tantalum and alloys of tantalum.

4. In the conversion of hydrocarbons of high 12 boiling point into hydrocarbons of lower boiling point in the liquid phase at a temperature between about 300 and 450 C. the step which comprises heating the said materials in a space confined by a material selected from the group 130 consisting of titanium, tantalum and alloys containing at least one of these metals and in the presence .of a non-metallic anti-carbon forming catalyst selected from the class consisting of selenium, tellurium, oxides of the heavy metals of 135 the third to the sixth group of the periodic systemand of iron, nickel and cobalt, while supplying heat by means of the catalyst itself which acts as the heating agent in the body of the liquid hydrocarbons of high boiling point.

5. In the conversion of hydrocarbons of high boiling point into liquid hydrocarbons of lower boiling point in the liquid phase at a temperature between about 300 and 450 C. the step which comprises heating the said materials in a 145 space confined by a material selected from the group consisting of titanium, tantalum and alloys containing at least one of these metals and in the presence of a non-metallic anti-carbon forming catalyst selected from the class cousislg.l d 150 boiling below a desired limit are distilled ofi'.

lill

selenium, tellurium, oxides of the heavy metals of the thirdl to the sixth group of the periodic system and of iron, nickel and cobalt while supplying heat in such amounts that only products boiling points in the liquid phase ata temperature between about 300 and 450 C. the step which comprises heating the said materials in a space which is conned by free titanium.

ALWIN MITIASCH. 8() 6. In the conversion of hydrocarbons of high GEORG STERN. boiling point intoliquid hydrocarbons of lower ERNST GALLE.

ss CERTIFICATE 0Fv CORRECTION. menno.' 1,922,491.- Amst 1s, 193s.

ALWIN MITIASCH, ET AL.

I t is hereby certified thaterror appears in the printed specification of the 'above numbered patent requiring correction as follows: Page l, line 1l, for 'free iron is" read metals are; and line ll2, for "metal" read free iron; and thai the and Letters Patent should be read with these corrections therein that the seme may conform to the record of the case inthe Patent Office.

Signed and sealed this 12th day of Deeinber,` A. D, 1 933,

went) Acting Commissioner of Patente'.

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