DE2358098A1 - PROCESS FOR THE PRODUCTION OF GASES CONTAINING HYDROGEN AND CARBON MONOXIDE AND A CATALYST FOR CARRYING OUT THE PROCESS - Google Patents

Description

MITSUBISHI CHEMICAL INDUSTRIES LIMITED
Tokyo, Japan

¹¹ Process for the production of gases containing hydrogen and carbon monoxide and a catalyst "for carrying out the process"

Priority: November 21, 1972, Japan, No. 116 892/72

The invention relates to a process for the production of hydrogen and carbon monoxide and optionally containing methane Gases and a catalyst for carrying out the process. ,

Water gas, which consists mainly of hydrogen and carbon monoxide, and which is used to make oxo compounds, methanol and ammonia is used, as well as a hydrogen, carbon monoxide and methane-containing gas mixture that serves as town gas, are made by so-called catalytic steam reforming processes produced in which hydrocarbons from natural gas or

Cash register

different petroleum fractions with / steam or a mixture of water vapor and carbon dioxide in the presence of catalysts in the
Gas phase are implemented. The catalysts used in these Reformierüngsverah -.- s are usually by addition of j

409822/0875 -

of a heat-resistant metal oxide, such as aluminum oxide, magnesium oxide, zirconium oxide, silicon

or one
Dioxide or calcium oxide / mineral! see clays which contain these oxides as main components, or their calcination products are produced to the nickel component. The catalytic conversion is carried out by passing the hydrocarbons and water vapor or a mixture of the hydrocarbons, carbon dioxide and water vapor through a plurality of heat-resistant tubular reactors which are filled with the catalyst and which are heated in an oven to temperatures of 650 to 900 C. will. However, these processes and the catalysts used in these processes have, inter alia, the disadvantage that, when the process is carried out industrially, carbon is deposited on the catalyst. This leads to a deterioration in the catalytic activity, to the breakdown and pulverization of the catalyst, which leads to an increased pressure drop and clogging of the pipes for the gases in the tubular reactor.

With a higher boiling point of the hydrocarbons used and higher content of unsaturated compounds in the carbons the amount of deposited carbonaceous products on the catalyst increases. As it has recently become

even
is borrowed / to use hydrocarbons other than naphtha, eg

heavy petroleum fractions as well as a C ^ fraction, which consists of a Residual oil from the naphtha cracking process for the production of When ethylene is produced, the solution to the problem of the deposition of carbon on the catalyst has become urgently required.

£ 09822/0875

It is known that the deposition of carbonaceous substances can be controlled by using a catalyst which contains the main nickel component and a special tungsten compound as well as a heat-resistant metal oxide in combination

'(see Japanese Patent Publication Nos. 2402 and 2403/1971), as well as by using an aluminum oxide with

'Significantly lower specific surface than carrier for this Catalyst (see BE-PS 773 081).

The separation of carbonaceous substances can also be carried out in can be controlled to some extent by adjusting the molar ratio from water vapor to the "hydrocarbons in the feed." elevated. However, this method is uneconomical.

The invention is based on the object of a technically advantageous Process for the production of hydrogen and carbon monoxide and optionally methane-containing gas mixtures create where hydrocarbons are present with water vapor of a new catalyst. This object is achieved by the invention.

The invention thus relates to a method for production

monoxide
of hydrogen and carbon / containing gases through XJmse't-

ζ en of hydrocarbons with water vapor in the gas phase and in the presence of catalysts, characterized in that

possibly

the reaction with steam and / or carbon dioxide in the presence of a catalyst which essentially consists of

(a) nickel,. ν; .. '. , - ■ _. '- - tungsten and. ^ _j

(c) a heat-resistant carrier, with at least a portion of the nickel and tungsten in the form of a nickel-tungsten alloy is present. '

The invention further relates to a catalyst for carrying out the process, which can be produced by heating a heat-resistant carrier containing a tungsten and nickel compound in the presence of a reducing agent to temperatures of 500 to 1200 ^° C.

The most varied of products can be used to manufacture the catalyst Nickel and tungsten compounds as well as heat-resistant metal oxides can be used. Preferably used as nickel compounds Nickel oxide, nickel nitrate and nickel carbonate are used, however Other nickel compounds can also be used, such as nickel chloride, nickel hydroxide and nickel sulfate. Specific examples suitable tungsten compounds are tungstic acid, tungsten oxide, ammonium tungstate and calcium tungstate. Specific Examples of usable heat-resistant metal oxides are aluminum oxide in the various modifications, magnesium oxide, Calcium oxide, zirconium oxide and silicon dioxide, as well as clays and diatomaceous earth, which the aforementioned oxides as basic components contain, as well as their calcination products.

The quantitative ratio of the aforementioned constituents in the catalyst can be proportionate depending on the constituents used wide limits. The nickel component, which is believed to be the essential ingredient for splitting the hydrocarbons represents, is usually on a content of 2 to J

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55 percent by weight, preferably 5 to 40 percent by weight, based on the total catalyst and calculated as NiO, are used. For the production of water gas, the nickel component is preferably used in an amount of 5 to 30 percent by weight Production of town gas is preferably used in a slightly larger amount, since the production of town gas is relatively is carried out at lower temperatures and the catalyst activity is lower.

the

The tungsten component believed to be responsible for / preventing deposition of carbon on the catalyst is responsible, should at least partially form an alloy with the nickel. Even with small amounts of the tungsten component leaves the object according to the invention can be achieved if the tungsten component is in the form of an alloy with the nickel. Usually the tungsten is made in a weight ratio of tungsten to nickel of at most 1: 1, preferably 0.1: 1 to 1.0: 1. The weight ratio of tungsten to Nikkei depends on the type of manufacture of the catalyst, in particular the way in which the tungsten is incorporated into the catalyst away. For example, if the tungsten on the surface of the Catalyst is present in high concentration, e.g. if the catalyst by impregnating a heat-resistant support nickel catalyst in a solution of Ammonium tungstate is produced, a small amount of tungsten is generally sufficient to achieve the object of the invention, compared to the case when tungsten is evenly distributed - present in the catalyst, e.g. when the catalyst is through jMissing nickel oxide with tungsten oxide and a heat-resistant J

4098 22/0875

digen metal oxide has been produced, Yfenn for example the tungsten is added according to the impregnation method described in Example 1, the deposition of carbon can be Control well on the catalyst with a weight ratio of tungsten to nickel of 0.2: 1 to 0.5: 1. Higher proportions are usually not required and one obtains a lower activity catalyst.

The catalyst used in the process according to the invention can be prepared by methods known per se, if at least part of the tungsten is present as a component of the catalyst with nickel in the form of an alloy. For example, can the catalyst components are applied to a heat-resistant support in a manner known per se, e.g. by mixing, Impregnation or coprecipitation, and then the catalyst components can under suitable methods Formation of a nickel-tungsten alloy in the catalyst can be reduced. In such a process, for example, a Mixture of the nickel compound shaped into molded bodies and the heat-resistant substrate in a solution of a tungsten compound impregnated, then the mixture is dried and calcined or a nickel compound, a WoIframverbindungen and a heat-resistant metal oxide or a metal compound which is easy to be calcined by heating or calcining, respectively Can be converted into a heat-resistant metal oxide, is in the form of a powder or a solution in the dry state or in Mixed together in the form of a slurry, then the Mixture dried, calcined and shaped. The calcining usually in air or in a stream of nitrogen at J.

409822/0876

Temperatures of about 500 to 1200 ⁰ C carried out. The catalyst components applied in this way to the heat-resistant oxide are then reduced.

The reduction can be effected either during or after calcining the mixture of catalyst components. A wide variety of reducing agents can be used for the reduction, such as hydrogen, gases containing free hydrogen or ammonia. The reduction is generally carried out at temperatures of from about 500 to 1200 ° C. and, depending on the preparation of the catalyst, for a period of from 1 to 15 hours. Thus, a Ni ckel * forms -Wolf ram alloy, the reduction -is preferably at least 5 hours, in particular at least 5 hours in the higher temperature range of about 700 to 1200 ⁰ C performed. .

The reduced catalyst obtained can, in addition to the Nickel-Wolf- ' ram alloy and the heat-resistant metal oxides metallic Contains nickel and metallic tungsten.

The mechanism by which the reforming reaction is influenced by the nickel-tungsten alloy in the catalyst used in the present invention is unknown. May be through the formation of a nickel-tungsten alloy, the active; Centers of nickel controlled and thereby the deposition of Suppresses carbon, resulting in excellent activity of the catalyst.

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- ⁸ "2358Ρ98

The method of the present invention is applicable to the production of a hydrogen and carbon monoxide as main components Water gas for the synthesis of, for example, ammonia or oxo compounds and for the production of methane rich city gas.

The reaction temperature doors in the inventive process are generally im.Bereich from about 300 to 100O ⁰ C, depending on the type of product gas mixture. To produce town gas that is rich in methane, the reaction is carried out at temperatures of about 350 to 60O ⁰ C, while temperatures of about 600 to 95O ° C are used to produce a water gas containing hydrogen and carbon monoxide as the main components. The reaction pressure is generally in the range from atmospheric pressure to 50 at.

The molar ratio of hydrogen to carbon monoxide in the invention produced gas mixture can be adjusted depending on the intended use of the gas mixture. To the To produce a gas mixture for the oxo synthesis, a mixture of water vapor and carbon dioxide is preferably used. A water gas with a molar ratio of hydrogen to carbon monoxide of about 1: 1 is obtained. For the production of a water gas with a higher hydrogen content for ammonia synthesis , preferably steam used alone.

A wide variety of hydrocarbons can be used as starting material for the process according to the invention, such as Paraffins from methane to higher molecular weight alkanes with up to _j

40 9822/0875

about 12 carbon atoms, such as propane, butane, hexane, heptane, octane and decane, as well as aromatic hydrocarbons. These Hydrocarbons can be used either alone or in admixture will. In practice this will be the technical implementation Natural gas, coke oven gas and various fractions are used, which arise during the petroleum distillation. Particularly preferred is the use of naphtha. Preferably is a hydrocarbon The starting material used has the lowest possible sulfur content.

In the process according to the invention, the quantitative ratio is Water vapor to the hydrocarbons used is usually about 1.0 to 6.0 moles of water vapor per gram atom of carbon in the hydrocarbons. This quantitative ratio is shown below referred to as the H2O: C ratio. The ratio used depends on the type of hydrocarbons used and the reaction conditions.

The space velocity used in the process according to the invention Hydrocarbons, such as naphtha, are generally in

-1
Range from about 0.1 to 10 hours, preferably 0.2 to

-1 ■

3.0 hours, depending on the type of hydrocarbon used

and the reaction conditions, as well as the quantitative ratio of water vapor to hydrocarbon. (Space velocity = liquid hourly space velocity)

The examples illustrate the invention. ■

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Example 1 I, preparation of the catalyst

a) Catalyst A.

A solution of 583.9 g of nickel nitrate in 2 liters of water and a solution of 954.4 g of magnesium nitrate in 2 liters of water / water are mixed with one another. A solution of 790 g of sodium carbonate in 7 liters of water is added to the solution obtained. Here, nickel and magnesium carbonate precipitate. The precipitate is filtered off, washed with water and mixed with 200 g of γ-aluminum oxide, ^{dried at 120 °} C. for 2 hours, then calcined in ^{air at 450 °} C. for 2 hours and finally at 800 ^{° C. in air for 5 hours.} The product obtained is thoroughly ground, shaped into cylindrical shaped bodies with a diameter of 3 mm and a height of 3 mm and then calcined in air at 900 ° C. for 5 hours. The product obtained is referred to as catalyst A. The catalyst consists of 30 percent by weight NiO, 30 percent by weight MgO and 40 percent by weight Al ₂ O ₃ .

b) catalyst B

^{Part of the catalyst A is heated to 800 °} C. for 10 hours in a mixture of hydrogen and nitrogen and reduced. The product obtained is referred to as catalyst B.

c) catalyst C

3 parts of the catalyst A are each impregnated with an aqueous solution of ammonium wolframate, so that catalyst samples with 4.1 percent by weight, 5.3 percent by weight or 8.2 percent

40 9 8 22/0875

^Γ . - - -'it - '' 235809B

Weight percent tungsten were obtained. The samples are 24 hours at 120 ° C in air dried, then 2 hours at 800 ⁰ C calcined and then 5 hours at 800 ⁰ C in the V / ater, material flow REDUCED. The samples obtained are referred to as Catalysts C-1, C-2 and C-3. The weight ratio of tungsten to nickel in these catalysts is 0.18 ': 1. 0.24: 1 and 0.38: 1. * Based on the X-ray diffraction analysis, the catalysts consist of a nickel-tungsten alloy, "tungsten, magnesium oxide MgAl ₂ O ^ and y-Al ^ O ,.

d) catalyst D

Four portions of catalyst B are each impregnated with an aqueous solution of ammonium tungstate so that catalyst samples containing 3.0, 4.5, 7.6 and 9.4 percent by weight of tungsten were obtained. Each of these samples is dried for 24 hours at 120 ° C. in a stream of nitrogen and calcined for a further 2 hours at 800 ° C. in a nitrogen atmosphere. The samples are designated as Catalyst D-1, D-2, D-3, and D-4. The weight ratio of tungsten to nickel in these catalysts is 0.12 ϊ 1, 0.18: 1, 0.33: 1 and 0.41: 1. MgAl ₂ O ^ and 7-Al ₂ O ₃ exist.

e) catalyst E

The catalyst D-2 is ^{reduced for 3 hours at 800 °} C. in a stream of hydrogen. The product obtained is referred to as catalyst E. By X-ray diffraction analysis, it was found that the catalyst is made of a nickel-tungsten alloy, tungsten, MgO, O ^ and. 7-Al ₂ O ^.

AO 9 8 2 2/0 8 7-5 ■ ".;

Γ "1

II. Reforming reaction

Desulfurized naphtha is prepared using the method described above As described, the catalysts prepared are subjected to steam reforming. The naphtha used has the following Composition:

Paraffins 68.1 percent by volume

Naphthenes 22.1 percent by volume

aromatic hydrocarbons 9.7 percent by volume specific gravity d ^ 0.730

Sulfur content 0.1 ppm

Distillation analysisj initial boiling point 48 ° C;

50 percent boiling point 119 ⁰ C and final ^{boiling point 181 0} C.

Steam reforming is carried out under the following conditions: -.

Reaction temperature: 750 ⁰ C;

Reaction pressure: Naphthas
(LHSV) S = Normal pressure; , 0 hour "¹; Space velocity of the 1 , 0; H ₂ O: C 2 Hour. reaction time 1

The reaction is carried out in such a way that the naphtha by means of a micro feed device is fed in a certain amount into an evaporator and evaporated there. The naphtha fumes are mixed with steam in a ratio of HpO: C of 2.0: 1. This mixture is preheated and fed into 6.25 ml of a catalyst bed in a quartz tube. The gaseous reaction products are used to separate

409 822/0875

tion of the water passed through a cold trap and then analyzed by gas chromatography.

The carbon deposited on the catalyst is after the end Implementation by introducing air or oxygen Carbon monoxide and carbon dioxide are burned, and the resulting gaseous reaction products are heated by a Layer of a copper catalyst passed to convert the carbon monoxide into carbon dioxide. The total amount of carbon dioxide is then determined quantitatively. The results are summarized in Table I:

tfolfram-
salary, ·. :
Wt.% Table I. analysis
Gas of the generated
, -Vol.-96-: co ₂ CH ₄ Note
kungen O ' ^H 2 CO 8.1 0 _; 3 Ver
equal Kataly
sator - 4.0 shot off
den of carbon
LenstjDff,
mg / hr . 70 _? 6th 21 _y 0 8.2 0.2 B. 5 ₇ 3 45.0 69 _; 8th 20.8 8.2 0.3 C-1 8.2 .3.8 70.2 21.3 8.3 0.3 C-2 3.0
S 5 . 3.0 70.2 21.2 8.1.-
8.1 0.3
0.3 Ver
equal
example
it C-3 4.1 70.0
70.4 21.5
21.2 8 _; 3 0.3 Il D-1
D-2 9.4 18.0
18.0 70; 2 21 j2 8.5 0.3 II- D-3 S 5 14.6 70.4 20 j 8 8 _; 0 0.3 D-4 16.9 7O ₇ 3 21.4 E. * V?

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From Table I it can be seen that a tungsten containing Catalyst only 'deposit small amounts of carbon. When using catalysts in which part of the Tungsten is in the form of a nickel-tungsten alloy, the carbon deposition is greatly reduced as the results with catalysts C and E show.

Example 2

Naphtha is subjected to steam reforming according to Example 1, however, an Inconel reactor with a fixed catalyst bed is used as the reaction vessel used. The reaction conditions are the same as in Example 1, but the reaction is at'einem Pressure of 20 at and a reaction time of 7 hours carried out. The results are summarized in Table II.

tungsten
salary, Table II Analysis of the
Gases, VoI CO generated
.-% 17.6
17.3 Note
kungen Weight % H ₂ 13.0
12.8 CO ₂ Ver
equal
example cataly- 8.2
7.6 shot off
dener Koh 55.6
55.8 13.8
14.1 saxor fuel,
mg / hr C-3
D-3 21.6
70.8

Example 3 I. Preparation of the catalyst

f) catalyst F.

A solution of 49.5 g of nickel nitrate in TOO ml of water as well as a Solution of 7.1 g of ammonium tungstate in 150 ml Ϋ / water are mixed together mixed. The mixture is mixed with 35 ml of α-aluminum

409822/0875

r - ■■■. - "·

oxide with a surface area of 10.2 m / g and mixed thoroughly. Then, the water is evaporated, the residue dried for 24 hours at "12O ° C, then in an air stream for 2 hours at 600 ⁰ C and 5 hours at 800 ° C calcined. The product obtained is pulverized and cylindrical moldings having a diameter of 3 mm and a height of 3 mm. These shaped bodies are then ^{calcined in air for 2 hours at 800 °} C. The product obtained is ^{reduced in a stream of hydrogen for 2 hours at 800 °} C. and referred to as catalyst F. The catalyst consists of about "20" Weight percent Ni, 10 weight percent W and 70 weight percent Al ₂ O *. Based on the X-ray diffraction analysis, the catalyst contains a nickel-tungsten alloy, olfram and Ct-Al ₂ O *.

• ·

g) catalyst G

A solution of 49.5 g of nickel nitrate in 100 ml Wasser'wird with "35 g Ct-Al ₂ O, was added, mixed thoroughly, and then evaporated. The residue is dried and then calcined for 2 hours in an air stream at 600 ° C for 24 hours at 12O ⁰ C. The calcined product is then pulverized and mixed thoroughly with 6.3 g of pulverized olefin oxide. The mixture is calcined 5 hours in air flow at 800 ⁰ C, .sodann to form cylindrical bodies with a diameter of 3 mm and a height of 3 mm deformed and calcined for 2 hours in a stream of air at 800 ⁰ C. The product obtained is reduced in a stream of hydrogen ^{at 800 ° C. for 2 hours.} This product is referred to as catalyst G. The catalyst consists of 20 percent by weight Ni, 10 percent by weight W, and 70 percent by weight Al ₂ O *. On the basis of the X-ray diffraction analysis, the catalyst contains _j

■ 40982 2/087 5

a nickel-tungsten alloy, tungsten and a-Al ₂ CU.

h) catalyst H

An aqueous solution of 49.5 g of nickel nitrate in 100 ml of water is mixed with 35 g of α-aluminum oxide with a surface area of 10.2 m / g, mixed thoroughly and evaporated. The residue is dried for 24 hours at 12O ⁰ C and then in an air stream

Calcined at 600 ° C for 2 hours and at 800 ° C for 5 hours. Thereafter the calcined product is thoroughly ground, the powder obtained into cylindrical shaped bodies with a diameter of

3 mm and a thickness of 3 mm and ^{calcined for 2 hours at 800 °} C. in a stream of air. ^{The product obtained is reduced in a stream of hydrogen at 800 °} C. for 2 hours and then impregnated in a solution of 7.1 g of ammonium tungstate in 150 ml of water, then ^{dried at 120 °} C. for 24 hours in a stream of nitrogen and then at 600 ^° C. for 2 hours in a stream of nitrogen and calcined at 800 ° C for 2 hours. The calcined product is referred to as catalyst H. The catalyst consists of 20 percent by weight Ni, 10 percent by weight W and 70 percent by weight AlpO. Based on the X-ray diffraction analysis, the catalyst contains Ni, WO ^ and Ct-Al ₂ O ^.

II. Reforming reaction

Naphtha is produced using the methods described above Catalysts F, G and H subjected to steam reforming. The properties of the naphtha used and the process conditions are the same as in Example 1. The results are summarized in Table III.

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- ■ 17 -.

Table III

Kata
lysa
gate Form. Of
Tungsten shot off
dener
Coals
material,
mg / hr Composition of he
generated gas, vol .-% CO CO ₂ CH ₄ Note
kungen
I.
I.
: F.
G
η Ni-W alloy
tion, W
Ni-W alloy
tion, ¥
WHERE ₃ 5.8
3.7
26.2 H ₂ 21.0
21.1
21.5 8.9
8.4
8.0 0.5
■ 0.3
0.2 Ver
same
example 70.6
70.2
70.3

4 0 9 8 2 2/0875

Claims (1)

Pat ent claims monoxide 1. Process for the production of hydrogen and coal / containing gases by reacting hydrocarbons with and
Steam in the gas phase / in the presence of catalysts, characterized in that the reaction with steam and optionally carbon dioxide is carried out in the presence of a catalyst which essentially consists of (a) nickel, (b) tungsten and (c) a heat-resistant carrier, with at least a portion of the nickel and tungsten in the form of a nickel-tungsten alloy is present, 2. The method according to claim 1, characterized in that the reaction is carried out in the presence of a catalyst which Nickel in an amount of 2 to 55 percent by weight, calculated than NiO. 3. The method according to claim 1 and 2, characterized in that. that the reaction is carried out in the presence of a catalyst, which contains tungsten and nickel in a weight ratio of 0.1: 1 to 1.0: 1. 4. The method according to claim 1 to 3, characterized in that that the reaction is carried out in the presence of a catalyst containing nickel in an amount of 5 to 40 percent by weight, calculated as NiO, and tungsten in a weight ratio too contains pimples from 0.1: 1 to 1.0: 1, and where at least one J A09822 / 0875 Part of the nickel and tungsten in the form of a nickel-tungsten alloy is present. 5. The method according to claim 1 to 4, characterized in that the reaction is carried out at temperatures of 600 to 95O ⁰ C and pressures of normal pressure to 50 atm. 6. Modification of the process according to claims 1 to 4 for the preparation of a gas mixture containing hydrogen, carbon monoxide and methane, characterized in that the reaction is carried out at temperatures from 350 to 60O ⁰ C and pressures of normal pressure to 50 atm. . 7. Catalyst for carrying out the process according to claim 6, which can be produced by heating a heat-resistant carrier containing a tungsten and nickel compound in the presence of a reducing agent to temperatures of 500 to 1200 ^° C. 8 «, catalyst according to claim 7», characterized in that one
the carrier containing a tungsten and nickel compound has been produced by impregnating the carrier with an aqueous solution of a tungsten and a nickel compound, drying the impregnated carrier and calcining at temperatures from 500 to 1200 ^° C. '. . :. 9ο catalyst according to claim 7, characterized in that the carrier containing a tungsten and a nickel compound by mixing the nickel compound with a heat-resistant one Metal oxide or one in the calcining into the metal oxide, • · ■: 409822/0875. convertible compound, impregnating the mixture with a
Solution of the tungsten compound, drying of the impregnated mixture and calcining at Temperatures.von 500 to 1200 ⁰ C has been produced. 10. Catalyst according to claim 7 Ms 9, characterized in that that hydrogen has been used as the reducing agent. 409822/0875