UA49430C2 - Catalyst for removal of organic and inorganic compounds of sulfur from gas or vapor, process for removal of sulfuric compounds from gases and method for removal of sulfuric compounds from vapor, for example, benzene - Google Patents

Abstract

The invention concerns chemical branch, in particular, the production of catalysts for removal of sulfuric compounds from gases or vapors. Application of copper-zinc-aluminium catalyst of the ow-temperature synthesis of methanol as catalyst for removal of organic and inorganic compounds of sulfur from gas or vapor. A process for removal of sulfuric compounds from gases on copper-zinc-aluminium catalyst of the low-temperature synthesis of methanol, which is preliminarily reduced by gas, which contains hydrogen, at high temperatures and pressure. A process for removal of sulfuric compounds from vapor, for example, benzene, at temperature of 125-160 DEGREE C and pressure of 1.6-2.0 MPa on preliminarily reduced copper-zinc-aluminium catalyst oflow-temperature synthesis of methanol. The use of invention allows increasing the degree of removal of sulfuric compounds from gas or vapor with the use of copper-zinc-aluminium catalyst of low-temperature synthesis of methanol.

Description

Description of the invention

The proposed invention relates to the chemical industry, in particular to sewers for cleaning gases or 2 vapors from sulfur compounds and methods for cleaning gases or vapors from sulfur compounds and can be used in chemistry, petrochemicals. in particular, in the production of ammonia, cyclohexane acetic acid, caprolactam and adipic acid, where it is necessary to clean the source natural, petroleum or process gas or steam from inorganic and organic sulfur compounds.

Widely known iron-chromium, nickel, tungsten, cobalt-molybdenum, nickel-molybdenum and 70 other catalysts for cleaning natural, oil or technological gas from sulfur compounds. The action of these catalysts is based on the catalytic hydrogenation or hydrolysis of organic sulfur to hydrogen sulfide, or oxidation to sulfur dioxide. The degree of decomposition of organic sulfur depends on the composition of sulfur compounds. After catalytic decomposition, the formed compounds of hydrogen sulfide and sulfur dioxide are absorbed on absorbers, the basis of which is active zinc oxide. For example, in the production of ammonia, natural gas is first purified on zinc oxide from hydrogen sulfide, then purified on cobalt molybdenum. or nickel molybdenum or palpdium catalyst from organic sulfur compounds, and then again on zinc oxide. During catalytic purification into gas. which is served on the catalyst, add hydrogen, or a hydrogen-nitrogen mixture with a hydrogen content of 2 - 1095. (11.

The disadvantage of these catalysts is the high cost of the catalysts, due to the presence of precious metals in them, and the need to use the catalysts together with the absorber.

A copper-zinc catalyst for purifying gases from sulfur compounds is also known. which includes copper and zinc oxides taken in an equal ratio (1.0 - 1.2):1. 2).

But this catalyst is used to purify gas from hydrogen sulfide, and it does not provide high-quality purification of gas from organic sulfur compounds.

The closest in terms of technical essence and achievable result is the copper-zinc-chromaluminum catalyst. Gee)

This is a NTK-4 low-temperature carbon monoxide conversion catalyst that is used in combination, in the form of a mechanical mixture, with a DIAP-10-2 copper-zinc catalyst for cleaning benzene vapor from organic and inorganic sulfur compounds in the production of cyclohexane.

The NTK-4 catalyst has the following composition of the main ingredients, in terms of oxides, in 96 mass: SiO 51 - 57, St2O53 12.5 - 15.5, 7p0 9.5 - 12.5, AI»OZ 17.6 - 21.6. co

The main ingredients of the DIAP-10-2 catalyst are zinc oxides (at least 77,905 wt.), copper (9 - 11 wt. Uv) and sulfur - Zmas.Oo |Z|. M

The disadvantage of the known catalyst is the insufficient quality of sulfur removal, since the content of residual sulfur in the finished product is 0.00008 wt.oo. This is due to the property of copper-zinc-chromaluminum catalysts of the NTK type 3o to change their micro- and macrostructure under the conditions of the desulfurization and passivation process, which does not is restored in the process of reducing the catalyst with hydrogen. In addition, the presence in the DIAP-10-2 catalyst of a large amount (C9omas) of sulfate sulfur reduces the activity of the following catalysts, for example, hydrogenation, because in the process of sulfur removal, which is carried out in the presence of hydrogen, sulfate sulfur turns into "hydrogen sulfide, which is a poison for hydrogenation catalysts and other catalysts, as it blocks the surface of C 50 catalysts with sulfides and, thus, reduces their activity. The basis of the proposed invention is the task of obtaining a more effective catalyst that provides high-quality purification of gas or steam from organic and inorganic sulfur compounds.

The task is solved by using a copper-zinc-aluminum catalyst for low-temperature methanol synthesis, as a catalyst for cleaning gas or steam from organic and inorganic sulfur compounds.

Copper-zinc-aluminum catalysts used for low-temperature synthesis of methanol are widely known in the world. Copper-zinc-aluminum catalysts (se) for low-temperature methanol synthesis by ISI (Great Britain) and I Godi (Germany) have become the most widely used. The ISI catalyst must contain not less than 2095 mass of Si, not more than 7095 mass of 7p0 and, additionally, one metal of group 2-4 - an oxide which is difficult to reduce. For example: the catalyst of the ISI company contains in mass: 53.2 СцО, 27.1 27п0, 5.5 AI250353 and 1495 mass со 20 make up the substances that are separated in the process of roasting at a temperature of 900 C. The best catalysts for low-temperature synthesis of methanol are catalysts with an optimal ratio copper and micro zinc or their oxides from 2:1 to 3/1.

SNM-1 catalyst (Severodonetsk low-temperature methanol) is produced in Ukraine. Catalyst

SNM-1 is identical in composition to the ISI catalyst. Catalyst SNM-1 contains oxide of copper, zinc and 22 aluminum in the following composition, in Uomas: 52 - 54 СцО, 24 - 28 7п0, 5 - 6 АИ2О3з. Requirements for its quality are specified

GF) in TU-09-5503-78.

Catalysts are produced and stored in a passive form - in the form of carbonates and oxides. Before use, they are reduced to the metallic form of copper with hydrogen or a gas containing hydrogen. Recovery is carried out until a constant amount of water is released. After recovery, operation and subsequent contact with air, 60 for example during unloading or technological stops, these catalysts are prone to pyrophoresis. Therefore, when unloading or stopping, catalysts are passivated, that is, the surface of the catalyst is gradually oxidized with steam or oxygen. (4).

SNM-U catalyst according to TU 6-04687873.047-00, which has high strength and porosity, is also manufactured in Ukraine. for the main technical characteristics of the SNM-U catalyst:

zx 11111111 o 00010701 vw the same

I'm going to go harder 1111111111111111111111111111111011501 5 The average mechanical strength, cutting the static conditions of the MP, is not less than 11111111 veedya 00000015 vaymvnsh 11111101 1 b. Activity at a temperature of 2209C, the content of crude methanol 853 cm syrtyuesmekatya, nemeshe 071 5 0 Shopytyumassurface of copper; matte is less than 00000001

The use of a copper-zinc-aluminum catalyst for the low-temperature synthesis of methanol for a new purpose, namely, as a catalyst for cleaning vapors from organic sulfur compounds, ensures high quality of cleaning. Sulfur content in purified products is 0.00002 - 0.0000Zmas.Uo

The technical result of the invention is the previously unknown property of the copper-zinc-aluminum catalyst for the low-temperature synthesis of methanol, which was discovered by the applicants, to purify gas or steam from sulfur compounds with high quality.

The advantage of the proposed invention is the possibility of purification from particulate compounds, both vapors and gases, as well as the possibility of purification from both organic and inorganic sulfur compounds.

Research has established that the action of the copper-zinc-potassium catalyst for the low-temperature synthesis of He! of methanol in the process of purifying gases or vapors from sulfur compounds in the presence of hydrogen is based on the property of this catalyst discovered by the applicants to initiate and accelerate reactions of hydrogenation and hydrolysis of organic sulfur compounds to hydrogen sulfide, exchange reactions, as well as reactions of the formation of sulfides by the interaction of sulfur with nonmetals, more electropositive (Si, 2p), than sulfur.

Research has also established that in the process of purifying gases or vapors from sulfur compounds, during (a) hydrogen reduction of a copper-zinc-aluminum catalyst for the low-temperature synthesis of methanol, its crystal structure is preserved, and its porosity increases, which precisely ensures highly effective purification. During passivation of the catalyst with oxygen and subsequent reduction with hydrogen, the strength of the catalyst does not deteriorate, which makes it possible to use all active copper for purification from sulfur compounds.

A method of purifying gas from sulfur compounds at elevated temperature and pressure using a copper-zinc catalyst is also known. "AND

Moreover, use a copper-zinc catalyst based on copper and zinc oxides with their ratio equal to (1.0 - 1.2):1.I(21.

The disadvantage of the known method is the low quality of gas purification from organic sulfur, since the action of this "catalyst" is based on the initiation and acceleration of mostly only exchange processes between oxides and hydrogen sulfide. - c The invention is based on the task of creating such a method of gas purification from sulfur compounds, in which, by changing the process conditions, in particular, the use of a catalyst that is new for this process, but known in itself in "" technology, high quality purification of gases from sulfur compounds is ensured , including organic sulfur compounds.

The task is solved by that in the known method of cleaning gases from sulfur compounds on

Its copper-zinc catalyst at elevated temperature and pressure, in the role of copper-zinc catalyst, a copper-zinc aluminum catalyst for low-temperature synthesis of methanol is used, which is previously regenerated with gas containing hydrogen.

ChK" The task is also solved by using a copper-zinc-aluminum catalyst with 50 low-temperature methanol synthesis, for example, the SNM-U catalyst, with the following composition of the main ingredients, in terms of oxides, in Uomas: (42) Si, 50.0 - 56.0 ; 7p0 24.0 - 28.0; AI2O»z 4.8 - 6.2.

And also by the fact that the gas purification process is carried out at a temperature of 120 - 3502C and a pressure of 0.1 - 10Mpa.

The use of a copper-zinc-aluminum catalyst for the low-temperature synthesis of methanol ensures high-quality purification of gases from organic and inorganic sulfur. The content of total sulfur in purified gas is about 0.00002 - О0.0000Zmass.9o

The method of gas purification from sulfur compounds includes: co-reduction of a copper-zinc-aluminum catalyst for low-temperature methanol synthesis; - gas purification at a temperature of 120 - 3509C and a pressure of 0.1 - 10Mpa. 60 There is also a known method of refining benzene from small sulfur impurities on a nickel-chromium catalyst diluted with a copper-magnesium catalyst |51I.

But this method does not provide high quality purification of benzene from sulfur and requires frequent overloads of the copper-magnesium catalyst due to its low mechanical strength. The service life of the copper-magnesium catalyst in the process of further purification of benzene from residual sulfur under production conditions is no more than one 65 years, and the sulfur content in the purified benzene is 0.00008 wt.o

There is also a known method of purifying benzene from sulfur compounds and hydrogenating benzene in one unit on layers of catalysts placed sequentially along the technological steam-gas mixture: desulfurization and hydrogenation of benzene. The process of purifying benzene from sulfur is carried out at a temperature of 140 - 1802C, a pressure of up to 2MPa on NTK-4 or NTK-10 sulfur-containing catalysts, with the following composition of the main components, 95% by mass in terms of oxides:

NTK-4 copper zinc chrome aluminum catalyst: CO 51 - 57, StoOz 12.5 - 15.5, 7pO 9.5 - 12.5, AI»O»z 17.6 - 21.6;

NTK-10 copper-zinc-calcium-aluminum catalyst: CO 35 - 45, 7p0O 25 - 35, AI2O»z - at least 16, CaO 5 - 11.

IEI

The disadvantage of the known method is that the high quality of purification from sulfur compounds in the known method 7/0 is achieved due to the absorption of sulfur by the nickel hydrogenation catalyst, which is impractical from the point of view of sulfur poisoning of the hydrogenation catalyst. In addition, the lack of control over sulfur absorption on the desulfurization catalyst also causes poisoning of the nickel hydrogenation catalyst with sulfur compounds during the operation of the desulfurization catalyst. This causes the need for simultaneous overloading of both catalysts.

The closest in terms of technical essence and achievable result is the method of cleaning steam, for example, benzene; from sulfur compounds at a temperature of 125 - 1609C and a pressure of 1.6 - 2.0MPa, on a pre-reduced copper-zinc-aluminum catalyst.

In the known method, a mechanical mixture of NTK-4 copper-zinc-chromium-aluminum catalyst is used with a copper content of 51 - 57 wt.%, zinc oxide 9.5 - 12.5 wt.%, chromium oxide 12.5 - 15.5 wt.%, and aluminum oxide 17.0 - 21.6 wt. and copper-zinc catalyst DAP-10-2, of the following composition, in Uomas in terms of oxides: 7pO - not less than 77.1, SiO - 9-11, sulfur - 3. (3).

The disadvantage of the known method is the insufficient quality of benzene purification from residual sulfur - 0.0000895 mass, due to the property of copper-zinc-chromaluminum catalysts of the NTK type to change their micro- and macrostructure under the conditions of desulphurization and passivation processes, which is not restored in the process of reducing Ha p; catalyst with hydrogen. In addition, the presence of a large amount of sulfur sulfate in the DAP-10-2 catalyst reduces the activity of the hydrogenation catalyst, because in the process of desulfurization of benzene, which is carried out in the presence of i) hydrogen, sulfate sulfur turns into hydrogen sulfide, which, together with purified benzene vapors, falls on the nickel hydrogenation catalyst, where it turns into nickel sulfide and thus poisons the catalyst and reduces its activity. In this regard, the method requires stops for overloading of hydrogenation and/or desulfurization catalysts.

The basis of the proposed invention is the task of creating a method for purifying steam, for example, benzene, from sulfur compounds, in which, by changing the conditions of the method, in particular, the use of a new, but already known in the art, catalyst, high quality purification of benzene from sulfur compounds is ensured compounds at

The problem is solved by the fact that in the well-known method of purifying steam, for example, benzene, desulfurized "KE" compounds, which is carried out at a temperature of 125-160 9C and a pressure of 16 - 2.0 MPa on a pre-reduced copper-zinc-aluminum catalyst, a copper-zinc-aluminum catalyst of low-temperature synthesis is used as a copper-zinc-aluminum catalyst methanol. "

The task is also solved by using a copper-zinc-aluminum catalyst for the synthesis of methanol, for example, a SNM-U catalyst with the following composition of the main ingredients, in terms of oxides, in - s to mass: c Si 50.0 - 56.0; 7p0 24.0 - 28.0; AIoO»z 4.8 - 6.2. "» The use of a copper-zinc-aluminum catalyst for the low-temperature synthesis of methanol for a new purpose, namely for the purification of steam, for example, benzene, from sulfur compounds, ensures high quality purification of benzene. The sulfur content in purified benzene is 0.0000295 wt.

Its Catalyst SNM-U is manufactured according to TU 6-04687873.047-00, has a strong spinel structure, sufficient copper content and high porosity.

Studies of the benzene purification process using the SNM-U catalyst showed that under the conditions of the purification process

CHK" of benzene from sulfur compounds, during the reduction of the SNM-U catalyst with hydrogen, its strong crystal structure with 50 is preserved, and its porosity increases, which is precisely what ensures the high efficiency of benzene purification from small sulfur impurities. During passivation of the catalyst with oxygen and subsequent reduction with hydrogen, the strength of the 62 SNM-U catalyst does not deteriorate, which allows using all the active copper to purify benzene from sulfur.

The activity, stability, and strength of the SNM-U catalyst remain at the proper level even when multiple cycles of passivation and catalyst recovery are performed. In addition, the term of its operation is in the process of cleaning

From sulfur, high sulfur capacity and efficiency in terms of cleaning quality, allow it to be used in the conditions of the main hydrogenation process (temperature, pressure, hydrogen concentration for the hydrogenation process), it is compatible with the hydrogenation catalyst. ko The advantage of the proposed method is the high productivity of the cleaning process and the reduction of the cost of the cleaning process due to the reduction of the number of stops for overloading of catalysts. 60 The proposed method of purifying benzene from sulfur compounds is carried out at a temperature of 125 - 160 2С, a pressure of 1.6 - 2.0MPa on a pre-reduced, freshly made SNM-U copper-zinc-aluminum catalyst with the following composition of the main components, mass 9o, in terms of oxides:

Si 50.0 - 56.0, 7p0 24.0 - 28.0, AIoO»z 4.8 - 6.2.

The proposed invention is explained by examples of a method for purifying gases from sulfur compounds and a method 65 for purifying benzene vapor from sulfur compounds. In both examples, the copper-zinc-aluminum catalyst manufactured in accordance with TU 6-04687873.047-00 is loaded into process gas purification and benzene vapor purification process reactors, where it is recovered in three stages: catalyst drying, decomposition of basic carbonates to copper oxide, and copper oxide recovery. The recovery process is controlled by the volume of allocated water. During drying, the catalyst is heated to a temperature of 100 - 1202C, in a stream of pure nitrogen, held at this temperature, and the water that is released is separated. Further, it is reduced with gas with a hydrogen content of 1.09506., at temperatures of 140 - 1609 and further - at temperatures of 180 - 3002С. The temperature range of 160 - 2002С corresponds to the stage of thermal decomposition of copper carbonates to oxide and subsequent reduction of the latter to copper. The completeness of the recovery is checked by gradually increasing the concentration of hydrogen in the gas to 1095. If the amount of separated water does not exceed the same amount during the recovery, then the catalyst is considered fully recovered.

Example 1

After the recovery of the catalyst, they switch to the reaction gas, which is to be purified from sulfur compounds.

Reaction gas, which contains, per bean: hydrogen - 70.0, carbon monoxide 24.0, nitrogen 1.5, methane 1.0, carbon dioxide 3.5 and organic and inorganic sulfur compounds in terms of total sulfur 1 - 2mg /m3, are passed through a reactor filled with a reduced copper-zinc-aluminum catalyst for low-temperature methanol synthesis with a volume velocity of 2000h-1. Cleaning is carried out at a temperature of 125 - 25090 and a pressure of 1 MPa. The gas after cleaning contains 0.Zmg/m (0.0000395), in terms of total sulfur.

In comparison with the known method - the prototype |2| the proposed invention allows for high-quality purification of gas not only from hydrogen sulfide, but also from organic sulfur compounds.

Example 2

The process of purifying benzene, which contains 0.00012 wt.bo of sulfur compounds in terms of total sulfur, is carried out by passing a mixture of its vapor with hydrogen through a reactor filled with a reduced copper-zinc-aluminum catalyst SNM-U, which corresponds to TU U 6-04687873.047-00. Liquid benzene is first fed into the evaporator at a rate of 0.8 - 1.2 time-1, where it is evaporated. Then benzene vapors together with hydrogen, which is fed at a rate of 800 - 12004-1, are fed into the reactor. The cleaning process is carried out at a temperature of 125 - 29 1602С, a pressure of 1.6 - 2.0Mpa. As the purification process is carried out at the outlet of the reactor, the content of total (9) sulfur in the steam-gas mixture, calculated on the output benzene, is determined. After purification, the sulfur content in benzene is 0.00002 wt.o

Compared to the known method - prototype (3), the proposed method provides better purification of benzene from sulfur, namely: 0.00002wt.9o against 0.00008wt.bo according to the prototype. о 3о Sources of information taken into account during the examination: со 1 Nitrogen reference book, volume 1, edited by E. A. Melnikov, Moscow, Chemistry, 1967, p. 296. 2 5 Mo801858, 1981. (prototype). h

From the Technological Regulation Mo11b6 of the Hydrogenation Department of the Alcohol and Ketone Production Department of Ge) of Organic Products from Aromatic Sulfur, dated 07.07.98. pp. 11, 12, 18. (prototype). - « 4 Technology of synthetic methanol, edited by M.M. Karavaeva, M. Chemistry, 1984, pp. 56 - 60. 5. BU Mo319206, 1979. 6 KY Mo2139843, 1999, "

Claims (1)

40 Formulas of the invention - c z» 1. Application of a copper-zinc-aluminum catalyst for low-temperature synthesis of methanol as a catalyst for cleaning gas or steam from organic and inorganic sulfur compounds. 2. The method of gas purification from sulfur compounds on a copper-zinc catalyst at elevated temperature and 45 pressure, which differs in that a copper-zinc catalyst is used as a copper-zinc catalyst for the low-temperature synthesis of methanol, which is previously reduced with gas containing hydrogen. (Se) Z. The method according to claim 2, which differs in that a copper-zinc-potassium catalyst for low-temperature methanol synthesis is used, for example, the SNM-U catalyst, with the following composition of the main ingredients, in terms of oxides, in 95 wt.: o 50 СО 50, 0-Bb,0 o 7pO 24.0-28.0 AI203 4.8-6.2. 29 4. The method according to claims 2, 3, which differs in that the gas purification process is carried out at a temperature of 120-1300°C and a pressure of 0.1-10 MPa. 7 5. A method of purifying steam, for example benzene, from sulfur compounds at a temperature of 125-160 9C and a pressure of 1.6-2.0 MPa on a pre-reduced copper-zinc-aluminum catalyst, which differs in that a copper-zinc-aluminum catalyst for low-temperature methanol synthesis is used as a copper-zinc-aluminum catalyst . b. The method according to claim 5, which differs in that a copper-zinc-aluminum catalyst for low-temperature methanol synthesis is used, for example, a SNM-U catalyst, with the following composition of the main ingredients, in terms of oxides, in 95 wt.: bo sio 500-560 7pO 24.0-28.0 AI203 4.8-6.2. with stump . . Official Bulletin "Industrial Property". Book 1 "Inventions, useful models, topographies of integrated microcircuits", 2006, M 12, 15.12.2006. State Department of Intellectual Property of the Ministry of Education and Science of Ukraine. s o "c) s o " (22) " - with . and? sh» se) sh» o 50 (42) F) ime) 60 b5