DE1002904B - Process for refining hydrocarbons or hydrocarbon fractions by means of hydrogenating catalytic treatment - Google Patents

Description

It is known to be involved in the coking, smoldering or gasification of hard coal, lignite, oil shale and similar fuels as well as hydrocarbons or hydrocarbon fractions arising from petroleum processing a hydrogenating refining in the presence of gases containing hydrogen and using a sulfur-resistant catalyst. In doing so, those in the hydrocarbons or hydrocarbon fractions containing disruptive substances such as sulfur compounds, nitrogen compounds and oxygen-containing organic compounds catalytically with the hydrogen to hydrogen sulfide, Ammonia and water and hydrocarbons are converted. There are gases for this process such as hydrogen, coke oven gas, coal gas, pressurized gasification gas and water gas are used. At reaction temperatures which are in the range of about 400 ° and above, carbon deposits occurred on the catalyst on, apparently from the decomposition of hydrocarbons and the use of carbon monoxide-containing ao Gases originated from the cracking of carbon dioxide. In addition, there was a strong reduction in octane number of refined hydrocarbons due to the simultaneous hydrogenation of olefins and of Aromatics, such as naphthenes, is due.

It has now been found that these disadvantages can be suppressed by using the mixture of Hydrocarbons or hydrocarbon fractions and gas containing hydrogen water vapor into the catalytic hydrogenation is introduced. Surprisingly, the presence of water vapor causes the Refining itself does not have a disruptive effect, but in many cases still favors it. Also damage to the contact - as a rule, a sulfur-containing contact is used for refining - do not occur. From the Invention there is the great advantage that carbon deposits on the contact are suppressed, even when refining at relatively high temperatures of e.g. B. takes place over 400 to about 500 ° C. Even a lowering of the octane number in the hydrogen refining is avoided. Occurs in some cases even an improvement in the octane rating. The amounts of water vapor required according to the invention are about 5 to 50 percent by volume, calculated on the gas freshly entering the process. Become beneficial applied about 15 to 35 percent by volume.

In the process according to the invention, as is known per se, it is possible to work with cycle gas. In In this case, somewhat larger amounts of water vapor, based on the fresh gas, are required. The work pressure can, as in the known method, be dimensioned. For example, it can be 5 to 100 atm.

The method according to the invention will be explained schematically and by way of example with reference to the drawing.

of hydrocarbons

or hydrocarbon fractions

by hydrogenating catalytic treatment

Applicant:

Metallgesellschaft Aktiengesellschaft,
Frankfurt / M., Bockenheimer Anlage 45

Dr. Wilhelm Herbert, Dr. Karl-Heinz Eisenlohr,

Dr. Hans-Werner Groß, Frankfurt / M.,

and Dr. Oskar Dorschner, Bad Homburg v. d. Height,

have been named as inventors

Through line 1, the hydrogen-containing gas to be used for refining is fed to the compressor 2, in which it is compressed. The refining is expedient at pressures of more than 1 at, advantageously carried out from 20 to 100 at. The compressed gas arrives, advantageously without cooling, through line 3 into the heat exchanger 4, which it leaves through line 5. Through the line 6 is the hydrogen-containing gas is water vapor in an amount of 5 to 50 percent by volume, e.g. B. 30 percent by volume, added. However, the gas can also be used at an elevated temperature, e.g. B. after it has reached about 100 to 300 °, z. B, 170 °, has been heated, can be loaded with water vapor in a known manner by sprinkling with water. The mixture of water vapor and hydrogen-containing gas then enters the evaporator 7, which is in its upper part 8 is filled with Raschig rings and equipped with a heating system at 9. In this vaporizer the product to be refined, e.g. B. gasoline or benzene stored in tank 10 via line 11, Pump 12 and line 13, optionally after preheating, fed to the evaporator 7. A small fraction of the goods to be refined, e.g. B. raw gasoline is deducted via the siphon 14 at 15. Through line 16 the mixture of gas containing hydrogen, water vapor and gasoline vapor from the evaporator 7 supplied to the further heating, the z. B. in the heat exchangers 17 and 18 and the heater 19 take place can. The gases pass from the heat exchanger 17 through the line 39 into the heat exchanger 18, from this through the line 20 into the heater 19, in which they are brought to almost the reaction temperature

609 836/411

3 4

the gas, and further generated by the line 21 in the contact gasification, obtained in a known manner, furnace 22, which with the sulfur-resistant catalyst 23 ge the gasoline z. B. is filled by treating the gas by means. The catalyst can be used in a known manner on washing oil. Tar and tar oil will be placed together in a sieve. Instead of being subjected to distillation in the drawing, in which, among other things, a reactor similar to a shaft furnace is shown, from the start of boiling up to a temperature of about 22, any other known reactor-210 ° C fraction can also be removed . This type of construction is used / In the reactor 22 light oil fraction takes place, which contains about 25 percent by volume of phenols during the passage of the gas-vapor mixture, e.g. B. contains can in a known manner, for. B. by extraction from top to bottom, by contact with the refining with hot entphenol water or with alkali lye. Hydrogen-containing gas, io entphenol. But this dephenolation is not water vapor and gasoline vapors or the like. Leaving through absolutely necessary, since the phenols, even if they enter the reactor and enter the reactor in countercurrent in larger quantities, give heat to the mixture flowing to the reactor the hydrogenating refining into hydrocarbons this in the heat exchangers 17 and 18 from. You are transformed. Gasoline and the optionally enter the heat exchanger 18 first, 15 dephenolated light oil fraction are combined and for the purpose of leaving it through the line 26, the heat exchanger 17 is used for the production of a suitable motor fuel and from there is subjected to catalytic refining through the line 27. The mixture has in the heat exchanger 4. Through line 28, for. B. the following composition:
the already at a temperature of z. B. about 120 ° density at 20 ° C 0 813

cooled mixture of hydrogen containing gas, * o _sulfur weight percent '['. '.'. '.'. '.'. '.'. '.'. '.'. Y. '.'. 0 ^ 65

Water vapor and gasoline vapors from the thermal _acid ole percent by volume 2

Exchanger m passed the cooler 29, m the water boiling start 64 ° C

Steam and gasoline vapors by cooling down to 5 percent by volume 71 ° C

temperature to be condensed. This cooler can be used for <c 930 q

Avoidance of ammonium carbonate excretion given 25 25 "100 ° C

may be sprinkled with fresh water. Cooling water 35 "^ q ^ o q

enters the cooler at 30 and exits at 31. ac " -Qgo q

Hydrogen containing gas, water and the refined rr "128 ° C

Gasoline reaches the 143 ° C separator through line 32

the 33, from which at 34 the raffinate and at 35 water 30 75 "'jggo q

is deducted. og "igQo q

The raffinate contains small amounts of sulphurous water at nc "203 ° C

substance as well as ammonia dissolved and is then to the end of boiling "210 ° C

their removal with diluted lye and water loss of boiling YYYY. YYYYYYYYYYYYYYYYYYYYY. 2.4 ⁰ I.

washed. The hydrogen containing gas is at 36-35 °

taken from the system and appropriately in the refining loss is 39 kg / 1000 kg raw material

Gas generating plant, which is the fresh gasoline in the process. The raffinate has the following composition: incoming hydrogen-containing gas supplies, e.g. B. before density at 20 ° C 0 795

the gasoline recovery of this plant for the recovery of _sulfur) weight percent 'YYYYYYYYYYYYYYYYY 0.034:

of the gasoline contained in the gut. However, it can be 40 _acid Q _le volume percent 0

also the raffinate contained in this residual gas at a boiling point of 6I ⁰ C

known manner, e.g. B. by adsorption with activated carbon, r volume percent 74 ° C

Cooling down or washing out with a washing oil obtained ^ g ^ o q

will. 25 "92 ° C

Part of the remainder from the plant at 36-45 or "970 q

gases can be recycled, e.g. B. in front of ^ r "105 ° Q

the compressor 2 or in front of the heat exchanger 4. er " 113 ° C

The method according to the invention can also be carried out at 25 ° C

Hydrogen refining of liquid hydrocarbons- 75 "143 ° C

substances or hydrocarbon fractions applied 50 or "153 ° q

will. These are then appropriately according to 95 "^ 930 q

preheating, possibly in the presence of end boiling "203 ° C

Gas containing hydrogen and / or water vapor loss of boiling point 3 2 ° /

happens, e.g. B. up to a temperature that is close

the reaction temperature of the reactor 22 lies in this 55 Since there is still hydrogen sulfide and ammonia introduced, e.g. B. bypassing the evaporator, it is washed with caustic soda and water the heat exchangers 17 and 18 and the heater 19. and then dried. Another treatment of the The hydrogen-containing gas can then be dispensed from the raffinate in most cases. at Heat exchanger 4 after admixing the water - difficult hydrocarbons, especially gasoline, steam directly to the heat exchanger 17 60 it can sometimes happen that the raffinate is not in which it is completely lightfast with the liquid if necessary. By a slight Nachzu refined good meets. treatment, e.g. B. by washing with diluted

Sulfuric acid and / or treatment with fuller's earth,

Example clay, silica gel, activated carbon or similar substances in

65 of the liquid phase at normal or elevated temperature

In the gasification of a weakly baking gas or in the gas phase, if necessary under pressure, leaves Flame charcoal with oxygen and water vapor under one however the desired complete lightfast pressure of 20 at for the generation of long-distance gas can be achieved without difficulty. This treatment that By-products of tar, tar oil and gasoline. These of the refining with the sulfur-resistant catalyst Substances are from the pressurized, through which 70 is downstream, can be advantageous in the presence of the

Hydrogen-containing gas and / or the water vapor take place.

Instead of this aftertreatment, however, the refined hydrocarbons or hydrocarbon fractions can also be fractionated. It has been found that a lightfast distillate passes over during this fractionation, while the substances causing the discoloration remain in the distillation residue. This can be kept relatively small, for. For example, only about 1 to 15 ° / ₀ of the supplied amount of the raffinate fractionation. The distillation residue is expediently added back to refined hydrocarbons or hydrocarbon fractions. In particularly difficult cases, this fractionation and the aftertreatment with dilute sulfuric acid, fuller's earth or the like can be used one after the other - in any order.

The refining of the raw gasoline takes place at a pressure that is advantageously slightly above the pressure of the long-distance gas. So z. B. at a remote gas pressure of 20 at, the pressure in the refining plant is kept at 25 at. ^{1000 Nm 3 of} fresh gas are supplied to the compressor 2 every hour through the line 1 and are brought to a temperature of 170 to 180 ° in the heat exchanger 4, which is optionally supplemented by an additional heating device. 250 kg of water vapor per hour, which is available at a pressure of 36 atm, is fed to this gas in line 5. The gas containing hydrogen enters the evaporator 7 together with the water vapor, which is kept at a temperature of 190 to 220 ° C. by the heating system 9. 1000 kg of raw gasoline are fed to the evaporator through line 13 every hour. From the line 15 15 kg of evaporation residue are withdrawn per hour. B. before its distillation, can be recycled. ^{1000 Nm 3 of} gas, 250 kg of water vapor and 985 kg of gasoline vapor leave the evaporator every hour through line 16, and these are brought together by heat exchangers 17 and 18 and heater 19 to a temperature which rises almost to the reaction temperature. The reactor 22 is filled with a sulfur-resistant catalyst based on cobalt, molybdenum, alumina and is operated at a temperature of about 380 to 500 °, e.g. B. at 400 to 420 ° operated. The loading of raw gasoline is about 0.1 to 1 t / cbm of catalyst filling and hour, expediently 0.3 to 0.5 t / cbm of catalyst filling and hour. As a catalyst, for. B. Molybdic acid is used on alumina, with molybdic acid concentrations of about 10% being used. Another highly active catalyst for the treatment of the fresh gas according to the invention can, for. B. obtained by intimately mixing 70 parts by weight of a commercially available aluminum oxide hydrate with a bayerite structure, which essentially serves as a carrier in the catalyst, with 18 parts by weight of molybdic acid, 8 parts by weight of cobalt hydroxide and 4 parts by weight of graphite. The mixture is pressed into the shape of small cylinders. No protection is claimed in the context of the present application for the production of this catalyst. After the gas-vapor mixture leaving the furnace has cooled in heat exchange and in the cooler 29, 33,946 kg of a gasoline refined material are obtained in the separator. Through line 36 1000 Nm ^{3 of} gas are withdrawn, which in the gas generation, z. B. before the gasoline wash after a pressure reduction of z. B. about 23 to 20 at can be reduced. The octane number of the raw gasoline was determined by the research method to be 75 without the addition of tetraethyl lead. The research octane number of the raffinate was found to be 78, while the research octane number of a crude product refined under the same conditions without the addition of steam according to the invention is only 68. Gasoline refined in the presence of water vapor and gases containing hydrogen is also much more sensitive to lead.

The gas discharged through line 36 contains carbon oxide in amounts of about 3 to 8 percent by volume. A substantial conversion of the carbon dioxide during the refining is therefore not necessary, which was carried out before the Refining would be necessary if refined with gas containing carbon dioxide and without the addition of steam would have been.

Claims (3)

PATENT CLAIMS: 1. Process for refining hydrocarbons or hydrocarbon fractions by hydrogenating catalytic treatment with hydrogen, Coke oven gas, coal gas, carbonization gas, pressurized gasification gas, water gas or the like. Containing hydrogen Gases, water vapor being introduced into the treatment, characterized in that for Avoidance of polymerization with the hydrogenation treatment and sulfur-solid catalyst resulting reductions in the activity of the catalyst water vapor in amounts of about 5 to 50 percent by volume, expediently 15 to 35 percent by volume, calculated on the fresh in the process entering gas, is added, with pressures of about 5 to 100 at and with temperatures of over 300 °, advantageously about 380 to 420 ° or higher, is worked. 2. The method according to claim 1, characterized in that the raffinate is fractionated and the Distillation residue in the refining, expediently to the hydrocarbons to be refined or Hydrocarbon fractions is returned. 3. The method according to claim 1 or 2, characterized in that after the hydrogenation treatment, the hydrocarbons or hydrocarbon fractions a slight aftertreatment with bleaching earth, alumina, silica gel, activated carbon or similar substances in the liquid phase at normal or elevated temperature or in the gas phase, if necessary Pressure and / or washing with dilute sulfuric acid. Considered publications:
British Patent Nos. 345,378, 424,531,
297;
U.S. Patent No. 1,981,305. 1 sheet of drawings ® 609 836/411 2.57