The invention relates to a metal coated supported catalyst which comprises a catalytically active Co, Ru and/or Fe metal supported on an inorganic oxide. The invention also relates to a method for the preparation of such a metal coated supported catalyst, wherein an inorganic oxide support is contacted with a Co, Ru and/or Fe compound, and the Co, Ru and/or Fe compound in the obtained contact product is reduced to a catalytically active Co, Ru and/or Fe metal supported on the inorganic oxide. The invention also relates to the use of the above- mentioned metal coated supported catalyst for, for example, the hydrogenation of carbon monoxide.

The object of the present invention is thus a metal coated supported catalyst which can be used for converting to hydro¬ carbons a gas mixture (so-called synthesis gas) which contains carbon monoxide and hydrogen. This process is generally also called the Fischer-Tropsch reaction. It is known that the catalyst of this reaction is calcined and, for the reduction of the metal oxides, the catalyst is treated in a hydrogen stream typically at a temperature of approx. 350-500 °C. It is typical of catalysts prepared by uhis process that the metal particles formed on the support are relatively large in size, i.e. the dispersion of the metal is low. Furthermore, the reduction of metal oxides, in particular cobalt oxides, is difficult, and even after a treatment with hydrogen a significant proportion of the metal is in oxidized form. It has been observed that the reduction degree and dispersion of the metal have essential effects on the activity of the cata¬ lyst and on the composition of the reaction product obtained by using it.

The greatest drawbac of conventional catalysts is indeed the disadvantageous hydrocarbon distribution in the reaction prod¬ uct, and thus insufficient yield of the desired hydrocarbon

products. Especially non-desirable products include methane and carbon dioxide. It has been observed that the product distribution follows the so-called Anderson-Schulz-Flory rule in the cases of all those catalysts for which conventional oxides are used as supports. According to the Anderson-Schulz- Flory distribution, for example, the highest attainable yield of Cj-C ₁₂ hydrocarbons is only approx. 48 % by weight. Further¬ more, the product distribution is wide and the reaction product contains hydrocarbons ranging from methane to large- molecule waxes, which decreases the value of the product and makes its utilization difficult. The low selectivity of the catalysts is the most significant factor limiting the competitiveness of this reaction.

The product distribution has been altered and improved by means of catalyst promoters. Examples of conventional promoters include the oxides of alkali metals, of several light transition elements, and of actinides. For example, on the basis of US patent publication 4 399 234, detrimental formation of methane can be decreased using a Th0 ₂ promoter.

It is known than, in order to improve the product distribu¬ tion, the oxide used as catalyst support can be replaced by a crystalline molecular sieve which contains silicon and aluminum, i.e. zeolite. For example, US patent publication 4 652 538 describes a catalyst in which the support used is large pore Y-zeolite. US patent publication 4 659 743 describes a catalyst in which a ZSM-5 type zeolite has been impregnated with an aqueous solution of cobalt nitrate. Zeolites have been used with the aim of maximizing the yield of Cj-C ₁₂ hydrocarbons, i.e. the so-called gasoline fraction. However, the formation of benzene and other aromatic hydrocarbons continues to be unsatisfactorily profuse.

It is known that, when cobalt carbonyl or some other organo- metallic cobalt compound, dispersed on a support, is used in-

stead of an inorganic salt as the starting material for cobalt, under carefully controlled conditions it is possible to prepare a catalyst in which the dispersion and degree of reduction of cobalt are high. When conventional oxide supports are used, the activity of such catalysts is good, but the total distribution of the products is in accordance with the Anderson-Schulz-Flory distribution.

For example, from the publication Journal of Catalysis, vol. 108 (1987), pp. 386-393, there is known a catalyst in which cobalt carbonyl is combined with a large pore Y zeolite sup¬ port. In the reaction product the proportion of C ₃ and C ₄ hy¬ drocarbons in particular is more advantageous than in the Anderson-Schulz-Flory distribution. However, the activity of the catalyst is low and the yield of products is therefore low. Furthermore, even at a low level of conversion the selectivity for methane is notably high.

The object of the invention is to provide a metal coated sup¬ ported catalyst, intended for the hydrogenation of carbon mon¬ oxide, by means of which C ₄ -C ₁₂ hydrocarbons can be produced, with a high yield, without the formation of a large amount of methane or hydrocarbons heavier than C ₁₂ .

These objects have now been achieved using a novel metal coated supported catalyst, intended for the hydrogenation of carbon monoxide and the conversion of synthesis gas, the catalyst being in the main characterized in what is stated in the char¬ acterizing clause of Claim 1. It has thus been realized that a catalyst more selective than previously and at the same time effective is obtained by using as the inorganic oxide support so-called silicate crystalline mesoporous material (SCMM) . The average pore diameter of such silicate crystalline mesoporous material is approx. 2.0-10.0 nm, and its pore spaces are delim¬ ited by microcrystallites which are made up of tetrahedral layers of silicon and oxygen and octahedral layers of a bi-

valent metal and oxygen, the silicon in the microcrystallites being in part replaced by aluminum and/or the bivalent metal being in part replaced by a monovalent metal. Without in any way limiting the present application, it can be assumed that, the silicon being in part replaced by aluminum and the bivalent metal being in part replaced by a monovalent metal, the charge equilibrium of the microcrystallites will vacillate, and elec¬ trostatic forces holding the microcrystallites in the pore formation will be generated.

According to one preferred embodiment, the microcrystallites in the silicate crystalline mesoporous material serving as the inorganic oxide support are made up of two tetrahedral layers of silicon and oxygen and one octahedral layer of a bivalent metal and oxygen, the octahedral layer being between t e said two tetrahedral layers. Such structures include smectite and mica structures. Especially usable silicate crystalline meso¬ porous materials include saponite, hectorite or stevensite mineral structured materials.

It is preferable that the bivalent metal in the octahedral layer is magnesium. The monovalent metal in part replacing it is preferably lithium.

Silicate crystalline mesoporous materials usable in the inven¬ tion, serving as the inorganic oxide support, are disclosed, for example, in Torii, K. , Iwasaki, T. , Onodera, Y, and Hata- keda, K. (1991) Chemistry of Microporous Crystal. Kodansha and Elsevier, Tokyo, pp. 81-88.

Although the composition of the silicate crystalline mesoporous material used as the support in the metal coated supported catalyst according to the invention is complicated and does not always correspond to the ideal formula according to the structure, the following approximate formula (I) can, however, be presented for it, the formula being:

Ea[Si4-bAlb] ^tetr [ (II)3-c.dM(I) _c πd] ^oct i2-e(OH,F) _e -nH ₂ 0 (I)

where

E is a removable monovalent cation, such as an organic cation,

M(II) is a bivalent metal;

M(I) is a monovalent metal;

D is a vacancy,

0 < a < 0.8,

0 < b < 0.8,

0 < c < 0.8,

0 < d < 0.4,

0 < e < 2.8,

0 < b+C < 0.8,

0 n < 20, and

superscripts te ^tr - and ^oct - mean that the cations and vacancies in the preceding brackets are parts of the tetra¬ hedral structure and, respectively, the octahedral structure.

E in Formula (I) is a removable monovalent cation, such as an organic monovalent cation. Its function in the preparation of the silicate crystalline mesoporous material used as the sup¬ port in the invention is to serve as a cation producing pore spaces, and thus its concentration at the beginning of the process is high. At the final stage of the process for prepar¬ ing the silicate crystalline mesoporous material, the said re¬ movable monovalent cation E is removed by heating, whereupon it leaves pore spaces delimited by the above-mentioned micro¬ crystallites. In fact, in Formula (I) the proportion a of monovalent cation E is always smaller than at the beginning of the preparation process, and preferably close to zero.

According to one preferred embodiment, the formula (II) of th silicate crystalline mesoporous material serving as the inor¬ ganic oxide support is:

[Si3. ₆ Alo.4] ^tetr [ g3] ^okt (O.OH)i2 (11)

where (0, OH) _2 means that the total combined number of the oxide oxygen atoms and hydroxy oxygen atoms in Formula (II) is approx. 12, and the superscripts ^te tr. _an _ oct. _mean that the cations of the atoms in the preceding brackets are parts of the tetrahedral structure and, respectively, the octahedral structure. In Formula (II), one-tenth of the silicon in an ideal tetrahedral layer has been replaced by aluminum, whereas none of the bivalent metal, Mg, has been replaced by a mono¬ valent metal. It is to be noted that Formulae (II) and (III) are also in accordance with the definition of Formula (I) .

According to another embodiment, the formula (III) of the silicate crystalline mesoporous material is:

[Si ₄ ]ter.[Mg2 _. 6Lio.4] ^okt (0,OH) ₁₂ (III)

where (0, OH) _ means that the total combined number of oxide oxygen atoms and hydroxy oxygen atoms in Formula (III) is approx. 12, and the superscripts tetr. _anc j oct. _m ean that the cations of the atoms in the preceding brackets are parts of the tetrahedral structure and, respectively, the octahedral structure. In this silicate crystalline mesoporous material, none of the silicon atoms in the tetrahedral layers have been replaced by aluminum, whereas in the octahedral layers 13 % of the bivalent metal Mg has been replaced by monovalent metal Li.

The support in the metal coated supported catalyst according t the invention has been described above both morphologically an chemically. Since, as stated, precise description of the sili¬ cate crystalline material is very cumbersome owing to practical difficulties, it is advisable to supplement the description with the physical properties of the silicate crystalline meso¬ porous material. According to one embodiment, the silicate

crystalline mesoporous material used in the invention has the following physical properties:

- amorphousness or low crystallinity

2

- specific surface area approx. 300-1000 m /g

- average pore diameter approx. 4 nm

- pore volume approx. 0.3-1.5 ml/g.

It is preferable that in the metal coated supported catalyst according to the invention the proportion of catalytically active Co, Ru and/or Fe metal is 1-20 % by weight, preferably approx. 2-10 % by weight, and most preferably approx. 5 % by weight.

As was pointed out above, the invention also relates to a method for the preparation of a metal coated supported cata¬ lyst, in which method an inorganic oxide support is contacted with a Co, Ru and/or Fe compound, and the Co, Ru and/or Fe compound in the contact product thus obtained is reduced to a catalytically active Co, Ru and/or Fe metal supported on an oxide.

The method according to the invention is thus characterized in that the solid inorganic oxide support used is a silicate crys¬ talline mesoporous material which has an average pore diameter of approx. 2.0-10.0 nm and which can be produced using the following steps: a) the following reaction components are reacted hydrother- ally i) a crystalline inorganic oxide the microcrystalline structure of which is made up of tetrahedral layers of silicon and oxygen and octahedral layers of a bivalent metal and oxy¬ gen, in which layers the silicon has in part been replaced by aluminum and/or the bivalent metal has in part been replaced by a monovalent metal, and ii) a removable cationic compound, such as an organic

cationic compound, to form a hydrothermal reaction product, and b) the product of the hydrothermal reaction of step a) is heated in order to remove the removable cationic compound, such as an organic cationic compound, whereby a silicate crystalline mesoporous material is produced.

A hydrothermal reaction is thus carried out in step a) . By a hydrothermal reaction, or hydrothermal synthesis, is meant a mineral preparation method in which the said mineral is crys¬ tallized out from a superheated (above 100 °C and above the pressure of one atmosphere) aqueous solution. A hydrothermal reaction is usually carried out in pressure vessels in which the temperature is far above the boiling point of water. Mine¬ rals prepared by hydrothermal synthesis are of an especially high quality, and they can be used in applications requiring microcrystallite structures.

Thus, in the hydrothermal reaction according to the invention, a crystalline inorganic oxide and a removable cationic compound are reacted with each other. It is preferable that the micro¬ crystallites in the crystalline inorganic oxide are made up of two tetrahedral layers of silicon and oxygen and one octahedral layer of silicon and oxygen, the latter being between the said two tetrahedral layers of silicon and oxygen. Smectites and micas are especially preferable inorganic oxides. Examples to be mentioned include saponite, hectorite and stevensite.

The bivalent metal in the crystalline inorganic oxide in item i) is preferably magnesium Mg, and the monovalent metal replac¬ ing it is preferably lithium Li.

Although the crystalline inorganic oxide in item i) is in real¬ ity non-ideal, i.e. it may deviate from its ideal crystal structure, an attempt can be made, nevertheless, to describe the crystalline inorganic oxide with general Formula (IV),

which is as follows :

[Si4-bAlb] ^tetr [ (II)3.d-c (I) _c πd] ^okt - i2-e(OH,F) _e • ι-H ₂ 0 (IV)

where

M(II) is a bivalent metal;

M(I) is a monovalent metal;

D is a vacancy,

0 < b < 0.8,

0 < c < 0.8,

0 < d < 0.4,

0 < b+c+2d < 0.8,

2 < e < 2.8, n is a number within the range 0.1-20, and

superscripts ^tetr - and ^oct - mean that the cations of the atoms and the vacancies in the preceding brackets are parts of the tetrahedral structure and, respectively, the octahedral struc¬ ture.

It is to be noted that the inorganic oxide of Formula (IV) may alternatively contain or not contain aluminum which in part replaces the silicon and a monovalent metal which in part re¬ places the bivalent metal. It is thus seen that the starting material for the hydrothermal reaction may contain partial replacement aluminum and/or monovalent metal, but it need not necessarily contain these replacement metals. Since a silicate crystalline mesoporous material always contains these replace¬ ment materials, materials which contain these replacement mate rials need to be added to the hydrothermal reaction in a case in which the crystalline inorganic oxide serving as the start¬ ing material does not contain these replacement materials.

According to one embodiment of the invention, the first start¬ ing material for the hydrothermal reaction, i.e. the aqueous oxide according to general Formula (IV) in item i), is a sili-

cate having general Formula (V)

[Sι ₄ . _b Alb] ^tetr [M(II)3-dad] ^okt Ol2-e(OH)e ^• nH ₂ 0 (V)

where 0 < b < 0.8, 0 < b+2d < 0.8, and M(II), d, e, n, ^tetr - and ^oct - are the same as in Formula (IV).

According to this embodiment, in the aqueous oxide starting material some of the silicon has always been replaced by alumi¬ num, but the bivalent metal has not been replaced by a mono¬ valent metal.

An estimate may also be presented of the structure of the prod¬ uct of the hydrothermal reaction of step a). The estimate is corresponded to by approximate general Formula (VI)

E _a [Si4-bAlb] ^tetr [M(II)3. _c . _d M(I) _c D _d ]o t.o ₁₂ . _e (0,F) _e ^• nH ₂ 0 (VI)

where

E is a removable monovalent cation, such as an organic mono¬ valent cation, 0 < a < 0.8, 0 < b+c < 0.8, 1.2 < e < 2.8, and

M(II), M(I), π, b, c, d, n, ^tetr ' , and ^oct ' are the same as in Formula (IV) .

It can be seen from the formula that the product of the hydro¬ thermal reaction always contains both a removable monovalent cation E and a monovalent metal replacing silicon and/or bi¬ valent metal.

As was mentioned above, the hydrothermal reaction of step a) means the preparation of a mineral by crystallization out from an aqueous solution at a temperature higher than the boiling point of water and at a pressure higher than atmospheric pres-

sure. It is preferable to carry out the hydrothermal reaction at a temperature of 100-250 °C.

The hydrothermal reaction is carried out between the crystal¬ line inorganic oxide described above and a removable cationic compound, such as an organic cationic compound. According to one preferred embodiment, in the hydrothermal reaction step a), the reaction component ii), i.e. the removable cationic com¬ pound, such as a cationic organic compound, is a compound which contains or forms an organic onium ion of an element belonging to Group 15 or 16 (latest IUPAC notation) of the Periodic Table of the Elements. The organic onium ion group may be a hydro¬ carbon group, such as an alkyl group, but also a group such as a mono-, oligo- or polyoxyalkylene group, which contains hete- roatoms, such as oxygen. Especially preferred compounds which contain an organic onium ion include quaternary ammonium com¬ pounds, such as trialkylmethylammonium compound, dialkyldi- methylammonium compound, or alkyltrimethylammonium compound. By alkyl is meant in this context an alkyl group having more than one carbon atom.

After the crystalline inorganic oxide i) has been hydrother al- ly reacted with the removable cationic compound ii), such as an organic cationic compound, the product obtained is a silicate crystalline material in which the microcrystallites have been retained but which has, amid the microcrystallites, removable cations, such as the above-mentioned cations of organic cation¬ ic compounds. In the second step, i.e. step b) , of the method for preparing the silicate crystalline mesoporous material used as a support in the invention, the product of the hydrothermal reaction is heated to remove the said removable cationic com¬ pound, whereby a silicate crystalline porous material forms at the same time. It is preferable to heat in step b) the product of the hydrothermal reaction of step a) to a temperature of 100-1000 °C, preferably to a temperature of 400-900 °C.

As was pointed out above, lower-valency metals partly replacing the silicon and the bivalent metal can be added to hydrothermal reaction step a), in which case they will promote the linking of the removable cation to the crystalline inorganic oxide and the formation of a silicate crystalline mesoporous material. It is preferable to react in step a), in addition to reaction components i) and ii), also a compound iii) which contains an ion of a monovalent metal M(I), preferably lithium Li, and/or an ion of a halogen, preferably fluorine F. A suitable compound of such type is lithium fluoride LiF.

The preparation of the inorganic oxide support used in the method according to the invention has been described rather precisely in the foregoing, since specifically its new struc¬ ture is crucial in the preparation of a usable metal coated supported catalyst. However, the silicate crystalline meso¬ porous material used as the inorganic oxide support in the method according to the invention is also contacted with a Co, Ru and/or Fe compound, and thereafter the contact product is reduced, whereupon the Co, Ru and/or Fe compound in the contact product is reduced to a Co, Ru and/or Fe metal supported on the said inorganic oxide.

When the silicate crystalline mesoporous material is contacted with a Co, Ru and/or Fe compound, it is advantageous that the silicate crystalline mesoporous material is impregnated with a solution of the Co, Ru and/or Fe compound. The contacting can be carried out advantageously also in such a way that the con¬ centration of the Co, Ru and/or Fe metal in the catalyst will be 1-20 % by weight, preferably approx. 2-10 % by weight, and most preferably approx. 5 % by weight.

It is especially advantageous that the silicate crystalline mesoporous material used as the inorganic oxide support is con¬ tacted with a Co compound, which is preferably selected from a group which includes cobalt salts such as cobalt nitrate

where n is 0-6, usually 6, and metalorganic compounds of cobalt such as cobalt carbonyl, preferably dicobalt octacarbonyl Cθ2(CO)g. In this case the silicate crys¬ talline mesoporous material can be impregnated with an aqueous solution of cobalt nitrate the concentration of the solution being preferably 10-300 mg/ml, most preferably approx. 100-250 mg/ml. According to another embodiment, the silicate crystalline mesoporous material is impregnated with a ^c 4~ ^c 10 ^a l^ ^ane solution, preferably hexane solution, of dicobal octacarbonyl Cθ2(CO)g, in oxygen-free conditions, the concen¬ tration of the solution being preferably 5-60 mg/ml, most pref¬ erably approx. 30 mg/ml.

The contacting is carried out preferably by using a dry sili¬ cate crystalline mesoporous material; the silicate crystalline mesoporous material can be dried, for example, under low pres¬ sure at a temperature above 100 °C. We refer to Examples 1 and 2. Next, the silicate crystalline mesoporous material is usual ly cooled before being contacted with the cobalt, ruthenium and/or iron compound. When impregnation with a solution is used, the preliminary treatment of the solution depends on the metal compound used; for example, when dicobalt octacarbonyl Cθ2(CO)g is used, care must be taken that both the solvent and the impregnation conditions are water-free, whereas when a cobalt salt such as cobalt nitrate is used, wate serves as a solvent and does not hamper the impregnation.

After impregnation, the solvent is dried off; care must be taken that the metal compound will not decompose in an uncon¬ trolled manner during the impregnation and/or the evaporation step. For example, dicobalt octacarbonyl Cθ2(CO)g decomposes already at a temperature above 52 °C.

As the result of the contacting, such as impregnation, there thus forms a dry silicate crystalline mesoporous material coated with a cobalt, ruthenium and/or iron compound. There-

after the coated silicate crystalline mesoporous material must further be reduced to a catalytically active Co, Ru and/or Fe metal supported on an inorganic oxide. This is done preferably by treating the said contact product with hydrogen gas at an elevated temperature, preferably with a hydrogen gas stream at a temperature of 300-550 °C. The most preferred temperature is approx 450 °C, and preferably the contact period is approx. 0.5-5 h, preferably approx. 1.0-4.0 h. When the reduction of the contact product is carried out using hydrogen gas at an elevated temperature, a slow and cautious heating of the con¬ tact product at the beginning of the reduction procedure is advisable. We again refer to Examples 1 and 2, in which the heating takes place at a rate of approx. 3 °C/min.

As was pointed out above, the metal coated supported catalyst according to the invention is especially well suited for the hydrogenation of carbon monoxide so that methane and long- chain, wax-type hydrocarbons are not produced in non-desirable amounts as byproducts. This means that the metal coated sup¬ ported catalyst according to the invention does not produce hydrocarbons according to the Anderson-Schulz-Flory distribu¬ tion; instead, more products are formed.

When the metal coated supported catalyst according to the in¬ vention is used for the hydrogenation of carbon monoxide, it is preferable to carry out the hydrogenation at a temperature of 200-300 °C. A preferred pressure is, regardless of the tempera¬ ture, 0.5-10 MPa. When, in the hydrogenation, carbon monoxide is reacted with hydrogen, the preferred molar ratio H2/CO is 1:1-3:1, preferably approx. 2:1. It is also preferable to use a fixed-bed flow reactor, which is preferably continuous-working, for the hydrogenation of carbon monoxide by using the metal coated supported catalyst according to the invention.

Example 1

A catalyst was prepared by the following procedure:

1.0 g of SCMM (Silicate Crystalline Mesoporous Material) serv¬ ing as catalyst support was dried in a glass vessel equipped with a tap ("Schlenk tube") at a pressure below 5 kPa at a temperature 200 °C for 2 h. Thereafter the SCMM was cooled. Dicobalt octacarbonyl Cθ2(CO) ₈ was dissolved in a sodium-dried organic solvent to a solution having a concentration of 30 mg/ml. It was observed in the experiments that the prepara¬ tion of a solution having a concentration higher than 60 mg/ml was difficult owing to the poor solubility of the carbonyl. When the concentration of the solution was lower than 5 mg/ml, the amount of solvent required increased so much that the pre¬ paration of the catalyst became difficult. The solvent used was n-pentane, n-hexane or n-heptane. 5 ml of carbonyl solution was injected in a nitrogen stream onto the SCMM, and the solvent was evaporated slowly by using reduced pressure. The injection of the solution and the subsequent evaporation of the solvent were carried out at a temperature below 52 °C, lower than the decomposition temperature of carbonyl. The formed product was transferred in oxygen-free conditions to a reactor tube made of stainless steel. The product was heated in a hydrogen stream of 30 ml/min at a rate of 3 °C/min to 450 °C, whereafter the tem¬ perature was maintained constant for 2 h. The formed catalyst, the cobalt content of which was approx. 5 % by weight, was cooled in a hydrogen stream to 200 °C, the starting temperature of the reaction.

Example 2

A catalyst was prepared by the following procedure:

1.0 g of SCMM serving as catalyst support was dried in a two- necked flask equipped with a tap and a drop funnel, at a pres-

sure below 5 kPa at a temperature of 200 °C for 2 h. Thereafter the SCMM was cooled. 0.247 g of cobalt nitrate Co(Nθ )-6H ₂ 0 was dissolved in distilled water so that the final volume was 1.2 ml, and the obtained solution was added onto the cooled SCMM by using the drop funnel. The two-necked flask was shaken for 15 in and was then allowed to stand overnight. The ob¬ tained product was dried in a rotavapor at a reduced pressure at a temperature of 60 °C. The obtained product was heated in a glass tube in an air stream of 10 ml/min at a rate of 2 °C/min to 300 °C and was maintained at that temperature for 2 h. The obtained product was cooled to 50 °C, and the air stream was replaced by a hydrogen stream. The product was reheated at a rate of 3 °C/min to 450 °C, whereafter the temperature was maintained constant for 2 h. The formed catalyst, the cobalt content of which was approx. 5 % by weight, was cooled in a hy¬ drogen stream to 200 °C, the starting temperature of the reac¬ tion.

Example 3

For comparison, a catalyst was prepared in which the support used was commercial Grace-Davison Siθ2 No. 57 having a specific surface area of approx. 330 m /g. With the exception of the selection of the support, the preparation procedure was the same as in Example 1.

Example 4

Catalysts supported on two different SCMM catalysts, Co(CO)/SCMM-l and Co(CO)/SCMM-2 (CO in the name of the catalyst refers to Co carbonyl in general) were prepared in accordance with Example 1. The chemical compositions of the SCMM supports were [Si _3>6 Al _{0 # 4} ] [Mg ₃ ] (0,OH) ₁₂ (SCMM-1) and

[Si ₄ ] [Mg _2#6 Li _0>4 ] (0,OH) ₁₂ . ^sc MM- ² .. A catalyst Co(N)/SCMM-l (N in the name of the catalyst refers to Co nitrate) was prepared according to Example 2. For comparison, a Co(CO)/Si0 ₂ catalyst

on a conventional Siθ2 support was prepared in accordance with Example 3.

CO hydrogenation reactions were performed in a continuous- working fixed-bed reactor by using the catalysts thus obtained. The reaction conditions were: temperature 200- 300 °C, pressure 0.5-10 MPa, gas flow rate GHSV 300-10000 h ^"1 , and synthesis gas composition H ₂ :CO = 1:1-2:1.

Table l shows the specific surface areas (SSA) of the support, its average pore diameters (APD) , as well as the CO conversion and the selectivities of the various catalysts for the various products, when the reaction conditions selected were: tempera¬ ture 233 °C, pressure 2.0 MPa, GHSV 2000 h ^"1 , and synthesis gas composition H2.CO = 2:1.

Table 1 Hydrogenation of CO by using Co(CO) /SCMM-1 and Co(CO)/SCMM-2, Co(CN)/SCMM-l and Co(C0)/Si0 ₂ catalysts.

Catalyst Support Co Selectivity (%) conversion

SSA (m ² g- ¹ ) APD (nm) (%) C-0 HC C" ₂ _ ₅ /C ₂ . ₅ i C ₄ . ₅ /C ₄ . ₅

Co(CO) /SCMM-1 674 4.2 12.3 22 78 49.2 13.8

Co(CO) /SCMM-2 703 3.3 18.4 22 76 44.4 5.4

Co(N)/SCMM-l 674 4.2 12.7 2 98 65.0 7.7

Co(CO)/Si0 ₂ 330 >10 12.1 14 86 30.7 1.2

C-O: oxygen-containing reaction products; HC: hydrocarbons; ^c "2-5/ ^c 2-5 ^: proportion of olefins of all C2-C5 hydrocarbons; i-C ₄ _5/C4_5: proportion of branched hydrocarbons of C ₄ -C5 hydrocarbons.

The production of branched hydrocarbons and light olefins is especially advantageous by using the catalysts of the present invention. The catalysts prepared from Co carbonyl produce large amounts of oxygen-containing products. The catalyst pre¬ pared from Co nitrate produces large amounts of light olefins, but only small amounts of oxygen-containing products.

Figure 1 shows, by means of Anderson-Schulz-Flory plots, the product distributions obtained using catalysts supported on the various supports. The abscissa is the number n of carbon atoms in the product molecule and the ordinate is ln[w(n)/n], where w(n) is the mass proportion of products which contain n carbon atoms. For the catalysts complying with the Anderson-Schulz- Flory distribution, the plot is, with the exception of C2 hydrocarbons, a declining straight curve. For the catalysts on SCMM supports according to the invention, the plot is a straight curve running at a relatively high level up to C- _j ^ hydrocarbons. Products heavier than this were not formed in measurable amounts, which is a significant advantage.

Figure 2 shows the proportion of olefins and branched hydro¬ carbons of the hydrocarbons as a function of the number of carbon atoms.

Figure 3 shows the structure of the SCMM support, below with the microcrystallite enlarged and above with the microcrystal¬ lites arranged into a mesoporous formation.