US2191156A - Reaction on carbonaceous materials with hydrogenating gases - Google Patents

Description

Patented 1 05.20, 1940 PATENT OFFICE REACTION N oARBoNAcEoUs MATERIALS WITH nrnnoonnn'rmc. GASES Mathias Pier, Heidelberg, and Walter Simon and Walter Kroenig, Ludwigshafen-on-the-Rhine, Germany, assignors to Standard-I. G. Company, Linden, N. J a corporation of Delaware No Drawing. Original application March 1,

1933, Serial No. 659,168. Divided and this ap- 'plication October 6, 1937, Serial No. 167,555.

In Germany March 9, 1932 5 Claims.

The subject-matter of the present application has been divided out from our copending application Ser. No. 659,168, filed March 1, 1933, which relates to the production of valuable hydrocarbons, for example those of low boiling point range from distillable carbonaceous materials, such as coal of all varieties, including pit coal and brown coal, shale, bituminous sands, tar,- mineral oils, shale oils, their distillation, conversion and extraction products and residues and the like, by hydrogenation reactions carried out with added hydrogenating gases, such as hydrogen or gases containing or supplying hydrogen and under pressure, preferably in circular course, in contact with catalysts, and in which is claimed the step of adding to the initial materials solid simple acid-salts of polyvalent metals and sulfuric, phosphoric and boric acids.

We have found that the conversion of distillable carbonaceous materials containing compounds having a basic and more particularly an alkaline reaction into valuable hydrocarbons by the abovementioned treatment can be effected in a'very advantageous manner by adding to the initial carbonaceous materials before or during the said conversion acids or acid salts in such an amount that at least 80 per cent of the said basic compounds are neutralized.

As examples of acids to be employed according to the present invention may be mentioned inorganic oxygen containing acids of sulphur or nitrogen and the anhydrides of said inorganic acids, if desired, together with water, further hydrohalic acids, 'e. g. hydrochloric or hydriodic acid, phosphoric acid and organic sulphonic and carboxylic acids.

It is of particular advantage to add simple solid acid salts to the initial materials. As examples of these acid salts may be mentioned those of polyvalent metals, such as tin, molybdenum, tungsten, manganese, magnesium, rhenium, zinc, cadmium, aluminum, vanadium or chromium.

Good results are for example obtained with acid magnesium phosphate, acid zinc phosphate, acid zinc borate, acid cadmium phosphate, acid vanadyl phosphate or acid chromic phosphate. The acid salts of sulphuric acid and the salts of pyro sulphuric acid also come into consideration. The acid alkali metal salts may also be employed, in particular acid lithium phosphate, but as a general rule the results obtained'therewith are not so good as those obtained with the salts herelnbefore referred to, and these latter should therefore usually be employed by preference. As examples of the said inorganic acids of sulphur or nitrogen may be mentioned sulphuric acid, sulphurous acid and nitric acid, or the organic carboxylic acids, acetic acid, formic acid and oxalic acid, and of the organic sulphonic acids benzene sulphonic acid, naphthalene sulphonic acid or sulphonated unsaturated hydrocarbons. In addition metals or compounds other than the "acid salts hereinbeforereferred to of metals of the 2nd to the 8th groupof the periodic system, in particular of the 6th group, such as for example sulphides, halides, phosphides, oxides,

carbonates or oxalates of zinc, aluminum, titanium, tin, lead, vanadium, bismuth, chromium, molybdenum, tungsten, uranium, manganese, rhenium, iron, nickel or cobalt may be employed. Said additional metals or compounds thereof are usually added in amounts between about 0.05 and 10 per cent by weight of the carbonaceous material undergoing treatment, for example between 0.1 and 5 per cent.

When adding the said acid substances in the destructive hydrogenation of oils as for example tar or mineral oils, or fractions thereof, the splitting action as well as the hydrogenation efiect is increased. Also the amounts of asphalts present in the reaction products are lower compared with processes working without'these acid additions.

The compounds having a basic reaction contained in the initial material have a restraining action on the pressure hydrogenation and tend to diminish the action of the catalysts of the type usually employed, in particularthose which have a non-basic character. By neutralizing the said compounds wholly or nearly so they are rendered harmless and even an excess of the said acids or acid salts above that required for neutralization may be employed. At the same time an improvement in the quality of the liquefied product (for example a reduction of the asphalt content) and an increase in the yield thereof results. -The amount of acid or acid salt which has to be added to completely neutralize the compounds having a basic reaction contained in the initial material, can be determined by simple preliminary trials. For example, a sample of the initial material to be destructively hydrogenated may be treated with an excess of an appropriately diluted acid at elevated temperatures and the part of the acid which is not used up for the neutralization determined after filtration by titration of the filtrate with alkali.

It has been found advantageous in many cases to employ exactly that amount of acid substances (which includes substances which are not by themselves acid, but which give rise to an acid reaction -when dissolved in water) required to neutralize the constituents of the initial materials having a. basic reaction, or an amount of acid substances exceeding or falling short of said amount by not more than 20 per cent based. on the total amount of acid substance employed.

The acids or acid salts may be added to the initial materials before or after the preheating. The acids may for example be atomized intothe ,reaction chamber together with or at the same time as the preheated carbonaceous materials are introduced thereinto. The acid substances employed according to the present invention may also be admixed with the initial materials in suitable intermediate vessels, which may be arranged before the reaction chamber or in the preheating system.

The acids or acid salts may also be added by soaking porous materials suchas active carbon, active silica, pumice stone, etc., with said acids or solutions of said acids or acid salts and supplying these to the reaction chamber.,

The expression tended to comprise the most various reactions and the catalysts employed in accordance with ment by destructive hydrogenation with hydrogenating gases of carbonaceous materials, such as coal-of all varieties, including lignite, other solid carbonaceous materials such as peat, shales and wood, mineral oils, tars and the distillation,

conversion and extraction products thereof The said treatment may be used to produce hydrocarbons of all sorts, such as motor fuels, middle oils, kerosene and lubricating oils. The said expression also includes the removal of non-hydrocarbon impurities, such as sulphuror oxygen-containing substances or nitrogen compounds by the action of hydrogen or gases containing or supply--v ing hydrogen from crude carbonaceous materials, for example the refining by treatment with hydrogen of crude benzol, of crude motor fuels or of lubricating oils. The said expression further includes the conversion of oxygenor sulphurcontaining organic compounds to produce the corresponding hydrocarbons or hydrogenated hydrocarbons, for example the conversion of phenols or cresols into the corresponding cyclic hydrocarbons or hydrogenation products thereof. Finally it includes the hydrogenaton of unsaturated compounds and more particularly of unsaturated hydrocarbons or of aromatic compounds and more particularly of aromatic hy-" drocarbons,vfor example to produce hydroaromatic hydrocarbons.

The said reaction with hydrogen or hydrogen containing gases are usually carried out at temperatures between 250 and 700 C. and as a rule between about 380 and 550 C. The pressures employed are usually in excess of 20 atmospheres and as a rule preferably in excess of 50 atmospheres. In some reactions, however, for example in the refining of crude benzol, relative-' 1y low pressures, for example, of the order of 40 atmospheres may be employed. Generally, however, pressures of about 100, 200, 300, 500 and in some cases even 1000 atmospheres come into consideration. I v r 'Ihev amount of hydrogen maintained in the reaction space and parts connected therewith, if any, varies greatly with the nature of the 'parhydrogenation reactio when employed in the present application is inthe result in view. In general, 400, 600, 1000 cubic meters or more of hydrogen, measured under normal conditions of temperature and pressure, per ton of carbonaceous materials treated may be used.

It is particularly advantageous to operate by continuously introducing freshcarbonaceous material into the reaction vessel and to continuously removeeproducts therefrom. If desired several reaction vessels may be employed in which different conditions of temperature and/or pressure may, if necessary, be maintained and in which different reaction products may be re-.

moved behind any of the reaction vessels. Materials which have not been sufliciently reacted on may be recycled or treated in 'a further reaction vessel.

The carbonaceous materials may be treated in the reaction in the liquid, solid or gaseous phase as required.

The reaction is advantageously carried out with streaming hydrogenating gases.

The gases for use in the reaction may consist of hydrogen alone or of mixtures'containing hydrogen, for example, a mixture of hydrogen with nitrogen, or water gas, or of hydrogen mixed with carbon dioxide, sulphuretted hydrogen, water vapor 'or methane or other. hydrocarbons.

The following examples will further illustrate the nature of the invention but it should be understood that the invention is not limited to the said examples. The percentages are by weight unless otherwise stated. e

Example 1 The vapors of a middle oil, obtained'by de- I structive hydrogenation under pressure of petroleum, are passed together with hydrogen under 200 atmospheres pressure and at a temperature of 430 9. over a catalyst rigidly arranged in a high-pressure-chamber and consisting of 50 parts of tungsten. sulphide and 50 parts of molybdenum bromide. The obtained product consists to the extent of,40 per cent of constituents boiling up to 180 C. When adding to the middle'oil before the treatment formic acid in an amount of 2 per cent calculated on the middle oil, a product is obtained consisting to the extent of 55 per cent of constituents boiling up to 180 C. The remainder is employable as illuminating oil or Diesel oil.

Example 2 1 A paste consisting of 2 parts -of a finely ground dried brown coal and 1 part of a heavy oil (boiling above 325 0.) obtained from the same coal by pressure hydrogenation is arranged in thin layers on plates superposed in a high'pressure autoclave. As a catalyst 2 per cent 'of tungsten sulphide is added to the coal. The autoclave, through which hydrogen continually flows under 250 atmospheres pressure, is heated in one hour amount as is necessary for the neutralization of the said alkaline constituents and the coal is treated as indicated, 96 per cent of the carbon of the coal is converted to valuable, mainly liquid hydrocarbons with only 6 per cent of asphalt.

For-neutralizing the coal it may be suspended in water and then treated with sulphur dioxide introduced into the suspension. If comminuted not dried coal is employed the sulphur dioxide is simply passed thereover. The coal thus treated is then dried and pasted up with'the aforesaid heavy oil. Also the paste of coal and heavy oil may be first prepared and then only be treated with sulphur dioxide.

Example 3 A petroleum freed from constituents boiling below 325 C. is subjected to a pressure hydrogenation at 445 C. and under a hydrogen pressure of 250 atmospheres in the presence of 20 per cent of a catalyst ground to a colloidal state of subdivision suspended in oil, and consisting of molecular amounts of molybdic acid, acid zinc phosphate and acid magnesiumphosphate.v The speed of flow is so selected that per each volume of reaction space one volume of initial material passes through per hour. In a separator annexed to the high-pressure-chamber, the temperature of which amounts to 435 C., a definite level of liquid is maintained. The unvaporized product collected therein is led back together with the catalyst suspended therein while still hot to the reaction chamber. On cooling the gases and vapors which leave the separator, a product is obtained, which consists to the extent of 50 per cent of constituents boiling up to 325 C.; the constituents obtained therefrom by distillation which boil above 325 C. are led back to the highpressure-chamber. When adding a mixture. consisting of molecular amounts of molybdic acid, zinc oxide and magnesium oxide, the same results can only be obtained by lowering the throughput to 80 per cent of that used with the acid catalyst.

Emample 4 Brown-coal is finely ground and made into a paste with an equal amount of heavy oil obtained from the same coal by destructive hydrogenation and is mixed with 0.1 per cent (based on the coal) of chromic acid. *This coal paste is then heated together with hydrogen under pressure to 455 C. and passed through a reaction vessel. 93 per cent of the carbon of the coal is obtained thereby in the form of valuable mainly liquid hydrocarbons, of which the products boiling above 325 C. contain 7 per cent asphalts. When adding on the other hand a like amount of acid chromium phosphate as catalyst and working under otherwise similar reaction conditions, then 96 per cent of the carbon of the coal is liquefied and the liquid products boiling above 325 C. only contain 5 per cent of asphalts.

Example 5 Finely ground pit-coal is made into a paste with an equal amount of heavy oil boiling above 325 0., obtained by destructive hydrogenation of the same coal. Vanadium oxide is added to the paste in an amount of 0.05 per cent calculated on the coal. The mixture is then heated together with hydrogen under a pressure of 200 atmospheres to 455 C. and passed through a reaction vessel. 89 per cent of the carbon of the coal is obtained thereby in the form of liquid products of which the products boiling above 325 C. contain percent asphalts. When adding in the place of the abovementioned catalyst acid vanadium phosphate and working under otherwise similar conditions, 92 per cent of .the carbon of the coal is obtained in the form of liquid products of phate.

Example 6 A fraction of petroleum boiling above 325 C. is heated together with hydrogen under a pressure of 200 atmospheres to 460 C. and the mixture is in a reaction vessel brought into contact with 20 per cent (calculated on the amount of petroleum) of finely divided acid chromium phos- The reaction participants are then passed into a separator, from which a product passes oil? in the vaporous form, which after condensation yields a condensate consisting of equal parts of benzine and middle oil. When adding as catalyst chromic acid in the same amount and under the same'reaction conditions, the same results can only be obtained by lowering the throughput to 85 per cent of that used with the acid catalyst.

Example 7 Finely ground brown coal is soaked with such an amount of sulphuric acid of 40 per cent strength, that per kilogram of dried coal '25 grams of sulphuric acid, calculated as 100 percent acid, are used. The coal is then made into a paste with an equal amount of heavy oil, obtained by destructive hydrogenation from the same coal, heated together with hydrogen under a pressure of 200 atmospheres to 450 C. and passed through a reaction vessel. 93 per cent of the. carbon of the coal is thereby obtained in the form of mainly liquid products. If the coal is not subjected to the acid-treatment, then the liquefaction is lowered by '7 per cent.

Instead of sulphuric acid, equivalent amounts of nitric acid, or benzine-sulphonic acid together with molybdlc acid may also be used.

Example 8' into a reaction vessel. The reaction products are passed without releasing the pressure into a separator, from which 93 per cent of vaporous products, of which 60 per cent boil below 325 C., are withdrawn while 7 per cent ,of high boiling products containing the catalyst are removed as a liquid. The vaporous products are subsequently conveyed together with hydrogen through a second reaction vessel maintained at 425 C. and filled with tungsten sulphide. A product is thus formed of which 75 per cent consists of benzlne and middle oil. The higher boiling portion' of this product is separated by fractional condensation from the portion boiling up to 325 C. and is returned to the second reaction vessel for further conversion into lower boiling products. Instead of the above mentioned coke also the light ashes and dust from a low temperature carbonization plant may be employed after impregnation with ammonium molybdate and subsequently with sulphuric acid.

Example 9 A mineral oil distillation residue from which constituents boiling above 325 C. have been separated is heated up together with hydrogen un-.

der a pressure of 200 atmospheres to about 370 C. by means of hotgases and vapors issuing from a reaction vessel. and passing in a heat regenerator in counter current to the said residue. The initial material is then mixed with 1 per cent of its weight of a catalyst consisting of an activated brown coal coke impregnated with 2 Der cent of its weight'of molybdic acid, whereupon the whole is heated together with hydrogen in a preheater heated with gas to 470 C. and then introduced into a reaction vessel. Before introducing the mixture into this vessel sulphonated paraflin wax is added thereto in an amount corresponding to 0.1 per cent, with reference to the initial material, of combined sulphur; in this manner a very active catalyst containing molybdenum and sulphur is obtained.

The reaction product is led from the reaction vessel into a separator, from which 93 per cent are carried off as a distillate consisting to the extent of per cent of constituents boiling above 325 C., while '7 per cent of high boiling products containing the catalyst are removed as a liquid. The distillate is passed at 425 C. through a second reaction vessel which is filled with tungsten sulphide. A product is thus formed of which per cent consists of Ibezine and middle oil. The higher boiling portion which is separated from the products boiling below 325 C. by fractional condensation is returned into the second reaction vessel for further conversion into low boiling products.

Instead of the said brown coal coke also wood charcoal or similar materials may be used as carrier'material for the molybdic acid.

In the appended claims the expression simple acid salt of an inorganic acid is intended to cover only salts in which part of the hydrogen 01' a non-complex inorganic acid is replaced by a base.

What we claim is: 1. A process for the production of valuable hydrocarbons by treatment of distillable carbonaceous materials containing compounds having a basic reaction with an excess of tree hydrogen at a temperature between 250 and 700 C. and under a pressure of at least 50 atmospheres and in the presence of. a non-basic catalyst the step of adding to the said initial materials before or during the said treatment an'acidic substance other than the catalyst selected from the group consisting of acids and acid salts in such an amount that at least per cent of the said compounds are neutralized.

2. In the process as claimed in claim 1 the step of adding a simple solid acid salt.

3. In the process as claimed in claim 1, the step of adding the acidic substance in an amount ranging between about 80 and per cent of the"amount required for neutralizing the compounds, having a basic reaction, which are present in the initial distillable carbonaceous, ma-

terials.

4. An improved process for catalytic destructive hydrogenation of carbonaceous materials containing basic substances which comprises adding an acidic substance other than the cata'- lyst to the feed stock in quantity sumcient to substantially neutralize the basic constituents contained therein and then subjecting the neutralized mixture to; the action of free hydrogen at atemperature between about 250 and-700 0., under pressure of at least 50 atmospheres and in the presence 01' a non-basic hydrogenation catalyst.

5. A continuous process according to claim 4 in which the feed material containing the added acidic substance is passed through areaction zone containing the catalyst.