DE2024282B - Process for the production of catalysts with a very fine distribution of the active components - Google Patents

Description

cntsnricht. in which the letters α to d as well as this fact of the activity reduction of Kalaly-

iaioren through recrystallization of the active components has long been known, and there has been no lack of attempts to meet it.

One of the most frequently used methods is to give the catalyst so-called "recrystallization-preventing" Additives in the form of certain metals or metal oxides in small quantities to add. However, the success of these methods is not satisfactory.

Another option is to cut the active components as finely as possible right from the start To bring distribution in or on the carrier in order to slow down the recrystallization. But this is so far only imperfectly succeeded. For example, you have active components in ionic form organic or inorganic ion exchangers applied in approximately atomic distribution, then reduced and used in this form as catalysts.

Apart from the fact that organic ion exchangers are no longer stable at higher temperatures, With this method, only a very low density of active molecules per unit volume is achieved and accordingly also only a low catalytic activity per unit volume, so that this method, although im Principle undoubtedly correct because of the atomic distribution of the active components, no broad unity found in technology.

The object was therefore to enrich the technology with catalysts in which the active Components at the same time in dense packing and in finely divided and so difficult to recrystallize form present that the catalysts have a high initial activity and this also at higher temperatures do not lose for a long time.

This can be achieved in a process for making active metal oxides, active metals and active metal oxides or active metals and / or active metal oxides and support material with very fine Distribution of the active components containing catalysts or catalyst support material with a large active surface by jointly dissolving at least one salt of a bivalent and a salt Trivalent metal in water, precipitation of the metals at elevated temperature in the form of basic carbonates and / or uniform mixed crystals and subsequent thermal or thermal and chemical treatment the precipitation products, which is characterized in that the salts of bivalent and trivalent metals in aqueous solution mixed in a ratio that the cation of the formula I

based on the theoretical amount of bicarbonate required for precipitation, containing basic carbonates ^{at a temperature of 3o to 100 0 C}

[Mel + Mei +] (OH) ₁₆ • CO ₃ • 4 H ₄ O

and / or basic carbonates belonging to the mixed crystal series of the formula II

[<Mg _e Ni (II) ₆ Co (Il) ₀ Cu (Il) ₁ I Zn _e Mn (H) /

Fe (II),) <Al _s Cr (IIl) j, Fe (III) ₂ )] CO ₃ (OH) ₁₆ · 4 H ₂ O

[<Mga Ni (II)), Co (II) ₀ Cu (IDd Zn _f Mn (II) / Fe (II),) <A1 "Cr (III)"

corresponds to, in the

a, b, c and d for whole numbers or decimal numbers from 0 to 6,

t for an integer or a decimal

number from 0 to 4.

/and,? for 0 or decimal numbers from 0 to 0.5. .v and ν for whole numbers or decimal numbers

from 0 to 2.0

and ζ for an integer or a decimal

number from 0 to 1.

with the proviso that 2 (a | ■ /> - (■ · · · ) 12 and 3 (.ν i ν Ir) = 6, with an aqueous solution of an alkali hydrogen carbonate which is an excess of up to 20 percent by weight Alkali hydrogen carbonate.being, precipitates, in the

a, b, c -§d d for whole numbers or decimal numbers

from O to 6,
λ: and y for whole numbers or decimal numbers

from 0 to 2 and e, /, g and 2 have the meaning given above

to have,

with the proviso that 2 (a + b + · · · + g) - 12 and 3 (x + y + z) - 6, the obtained uniform basic carbonates and / or mixed crystals dries, and calcined or calcined and reduced and so catalysts and / or catalyst support material wins.

The catalysts obtained in this way contain the active component (s) in close packing and nevertheless in finely divided form.

As is known, recrystallization in solids is based on processes of changing places. Through the atomic distribution of the active components produced by the process according to the invention Catalysts are at a given temperature for the formation of larger crystallites, i. H. for recrystallization, much more change of location is required than if the distribution, such as. B. with drinking contacts, is already much coarser from the production point of view. Possibly also the one for the change of place required activation energy increased by the inventive method. As is well known, cause paracrystalline and other lattice disturbances inhibit recrystallization. To generate such Lattice disturbances due to the incorporation of foreign atoms or molecules is an atomic distribution of the Components required. Since there is such a distribution in the method according to the invention, the Possibility of forming such recrystallization-inhibiting lattice defects through the manufacturing method given.

Compounds which, after thermal or thermal and chemical treatment, become so active Lead catalyst systems are, for example: uniform chemical compounds such as

Mg ₈ Al ₈ CO ₈ (OH) ₁₆ · 4 H ₂ O
Ni ₆ Al ₂ CO ₃ (OH) ₁₆ · 4 H ₂ O
Co ₆ Al ₂ CO ₃ (OH) ₁₆ -4 H ₂ O
Cu ₆ Al ₂ CO ₃ (OH) ₁₆ · 4 H ₂ O

and uniform mixed crystals such as

Mg ₁ Ni ₃ Al ₂ CO ₁ (OH) _1n 4 H ₂ O Mg ₃ Ni ₃ Al _1-8 Cr _0-2 CO ₁₁ (OH) _1n 4 H ₂ O

Mg ₁ Ni ₁ AIi _s C ₀ , ₁ (, "Mg ₄ Ni _{1 0} Co _{0 r} , Cu ₍₎ , Al ₂ CO ₃ (OH) CAlCO (O

· 4H ₂ O _n · 4H ₂ O

4 H ₂ O

Mg ₃₁₃ Ni _11n Co ₀₁₅ o ₁₇
CO ₃ (OH) ₁₆ · 4 H "O
Mg ₁ Co ₁ AlXO ₁ (OH) ₁₆
Mg ₅ Co _n-9 Mn _0-1 Al ₂ CO ₁₁ (OH) ₁₁₁ ■ Mg ₃ Cu ₁ Al ₂ CO ₃ (OH) _1n · 4 H ₂ O Ni ₃ Co ₁ Al ₂ CO ₁ (OH) _1,. ■ 4 H..O

4 H ₂ O

5 6

Ni ₂ COaCu ₂ Al ₂ CO ₃ (OH) ₁₆ · 4 H ₂ O nat into consideration. But it is also possible to use ammonium

Ni ₃ Zn ₃ Al ₂ CO ₃ (OH) ₁₈ · 4 H ₂ O bicarbonate to be used in the precipitation. Self-

Ni ₆ Al _{1> fl} Cr _{0> 1} CO ₃ (OH) _ie · 4 H ₂ O can also be understood to include mixtures of the above

Co ₃ Cu ₃ Al ₂ CO ₃ (OH) ₁₈ · 4 H ₂ O bicarbonates are used. Also is

Co _{4> 2} Cu _li2 Mn _0p8 Al ₂ CO ₃ (OH) _le · 4 H ₂ O 5 it is possible to precipitate the metal ions with solutions

COs] ₅ MnO ₁₅ Al ₂ CO ₃ (OH) ₁₈ · 4 H ₂ O of alkali carbonates, such as sodium carbonate and / or

Co ₀ Al _li9 Cr _0il CO ₃ (OH) ₁₈ · 4 H ₂ O potassium carbonate, if one during

Cu ₃ Zn ₃ Al ₂ CO ₃ (OH) ₁₆ 4 H ₂ O of the precipitation of carbon dioxide in the alkali

carbonate solution initiates, but what in the end also

With the formation of an active catalyst, the result is precipitation with bicarbonates,

suitable component metals are all in formula I is decisive for the activity of the catalysts

To understand the metals listed, in particular in each case that the precipitation of the hydrogen carbonates

Nickel, cobalt, copper, zinc, iron and chromium. is carried out so that the by the formulas II

As described for the formation of a catalyst support material and IJI compounds in pure form

suitable metals are magnesium, zinc and aluminum. The quality of the precipitation can be determined by X-ray

and chromium, especially magnesium and aluminum analysis, can be checked quickly and easily because

called. the described compounds all depend on the structural

In general, the type according to the invention is used

proceed as follows: Mg ₆ Al ₂ CO ₃ (OH) ₁₆ · 4 H ₂ O

For the production of active components 20 ^{6e z 3V / 1β}

and / or carrier material chosen are in are and accordingly all quite characteristic

Form of water-soluble salts, such as chlorides, give X-ray diagrams. This results in the

Sulphates or preferably nitrates, together in great advantage, that immediately after the precipitation

Dissolved water, specifically in a quantitative ratio, of the catalyst precursor can be checked whether the

the catalyst which can be prepared from the desired composition of the catalyst, the desired activity

sators comes as close as possible and will own in its stoichio- nal or not.

metry of the formula I. This metal salt solution If the basic carbonate does not have the required level of about 0.5 to 5 molar total, preferably uniformity, it can be of metal ions without large tech 1.0 to 4 molar. It is resolved again at a niche effort and temperatures of 50 to 100 ° C., preferably 80-30, are precipitated again. In contrast, in the case of catalysts which were heated ^{to 10O 0 C and prepared within 1} I ₂ to 10, in advance by conventional methods, preferably 1 to 3 minutes with an equivalent activity only on the finished and confectionery amount or preferably a low one Excess ionized catalyst can be determined. Using a 50 to 10O ⁰ C, preferably from 80 to 10O ⁰ C blank of Heizkamera radiographs darerhitzten be 1- to 5-, preferably 1.5 united to 4molaren 35 beyond a given composition of the solution of a Alkalibicarbonais. Preference catalyst precursor to gain clues that work wisely with an excess of alkali allows the life of the bicarbonate that can be produced from it, up to 20 percent by weight, of the preferred catalyst to be estimated.

wise from 0.5 to 3 percent by weight, based on the extremely fine distribution of the active theoretical amount of bicarbonate. After 40 components, even catalysts with one of the addition of the metal salt solution, the addition of the metal salt solution is expediently a significantly lower content of expensive active components, about 10 to 30, preferably 15 to 20 minutes, the same good activities as previously usual, then the resulting precipitate is filtered off, catalysts with a much higher level Content of washed with water and at temperatures of expensive active components. In addition to the resulting 50 to 20O ⁰ C, preferably 100 to 160 ° C, dried. The low production costs associated with this are a major factor. The basic carbonates are obtained in almost quantitative yields. The main advantage of this is that they can be calcined for much longer and, in the case of sischen carbonates, or can use higher temperatures than previously calcined and reduced. For calcination, the known catalysts are used without the activity of precipitates significantly decreasing for 5 to 40, preferably 15 to 30 hours 50 due to recrystallization,
to a temperature of about 200 to 600 ° C., preferably 250 to 400 ° C. In addition, nickel catalysts according to the invention can be heated. Here, the basic access catalysts, in contrast to Raney nickel without capitalized carbonates are completely or partially in the tätsverlust correspond to temperatures of over 400 ^G C sponding oxide compounds transferred. To be used by.

It is also a suitable choice of the reaction conditions. It is possible according to the invention or according to the invention to split off only the water of crystallization from the basic catalysts for the carbonates in question. coming metals contained in them or their As far as the calcined products reducible oxides are supplied to the usual uses who contain metal oxides - as such would be in particular the. For example, see them as dehydrating. To name the oxides of nickel, cobalt, iron, manganese and dchydration, isomerization, conversion, copper, these oxides can subsequently be dealkylation, methanation and fission catalysts or at the same time to de · -, corresponding metals and as Contacts for crack reactions are reduced. The reduction is within use. In particular, cobalt and / or 5 to 100 hours, preferably 10 to 25 hours. Nickel and / or copper-containing erfmdungs- and at temperatures from 180 to 500 ^c C, preferably 65 modern catalysts suited as hydrogenation 250 to 450 ° C. accomplished. suitable for catalysts.

In particular, alkali hydrogen carbonates can also be used by calcining the

Sodium hydrogen carbonate and potassium hydrogen carbonate-described mixed crystals are obtained

partly with special
carrier material for others
turn.

Advantage as a catalyst active component ver

example 1

The following solutions were made:
Solution 1:

6 moles of Mg (NO ₃ ) ₂ · 6 H ₂ O
2 moles of Al (NO ₃ )., · 9 H ₂ O
dissolved in 12 liters of water and

Solution 2:

1542 g (18.35 moles) NaHCO ₃
dissolved in 12 liters of water

Both solutions were separated and heated at 8O ⁰ C and then added to the solution 1 with stirring for about 2 minutes to solution. 2 The resulting precipitate was filtered off, washed and ^{dried at 150 °} C. for 20 hours. According to the Debye-Scherrer diagram and analysis, the dried product consists of a uniform compound of the formula

Mg ₆ Al ₂ CO ₃ (OH) ₁₆ · 4 H ₂ O

d values of the X-ray diffraction lines: 7.75; 3.88; 2.58; 2.30; 1.96; 1.77; 1.66; 1.525; 1.495; 1.42; 1.28.

This compound was then calcined over 20 hours at 300 C ^c. Under these conditions, this compound only releases its crystal water. The resulting product has a surface area of 76.3 m ² / g, a micropore volume Vpmicro of 0.17 cm ³ / g, a macropore volume Vpmacro of 0.30 cm ³ / g and a mean pore radius of 123.8 Å (determined by BET. Mercury porosimetry).

It can already be in this form as a dehydrating.

Isomerization and dehydrogenation catalyst as well Catalyst can be used for cracking reactions.

It is also suitable as a catalyst carrier material for other active components.

If the calcination product is heated to 400 ° C. for a further 20 hours, _{an oxide mixture is formed with elimination of water and CO 2} , in which the AUO _{3 is} so finely divided in MgO that it cannot be seen _{as Al 2} O _{3 in the X-ray diagram.} The crystallite size of the MgO is about 40 Å.

The oxidic product formed by this decomposition can also be used with advantage as a dehydrogenation catalyst or used as a catalyst support material.

Examples 2 to 13

As in Example 1, the mixed crystals listed in the table below were precipitated and dried. The i / values of the X-ray diffraction lines were used to characterize the compounds determined.

For all mixed crystals listed, the intensity is of the lines as follows:

very strong at 7.5 to 7.9 A.

strong at 3.7 to 3.95 Å; 2.55 to 2.65 Å;

1.51 to 1.56 Å and 1.47 to 1.51 Å.

All other lines are very weak to medium strong.

Table 1

at
game Manufactured mixed crystals rf values of the X-ray diffraction lines [A] 7.75 3.88 2.63 2.58 i 2.30 1.96 1.77 l, 66j 1.525 1.495 1.42 1.28 2 Mg ₆ Al ₂ CO ₃ (OH) ₁₆ · 4 H ₂ O 7.75 3.88 2.62 2.58 j 2.30 1.96 '1.77 1,661,525 1.49 1.42 1.3C 3 Ni ₆ Al ₂ CO ₃ (OH) ₁₆ ■ 4 H ₂ O 7.50 3.80 2.57 ' 2.30 1.96 1.75 1.52 1.49 4th Ni ₃ Mg ₃ Al ₂ CO ₃ (OH) ₁₆ · 4 H ₂ O 5 Ni _0-5 Co _n , _7S Cu ₀ . ₃₅ Mg ₄ Al ₂ CO ₃ (OH) ₁₆ 7.50 3.80 2.55! 2.30 1.96 ^: , 1.52 1.49 4H ₂ O 7.75 3.88 2.68 2.30 1.96 1.54 1.51 6th Co ₃ Mg ₃ Al ₂ CO ₃ (OH ₁₆ · 4 H ₂ O 7.75 3.88 2.58; 2.30 1.96 1.54: 1.51
I. 7th Co ₆ Al ₂ CO ₃ (OH) ₁₆ · 4 H ₂ O 7.70 3.80 2.5812.30 1.96 '1.53 1.49 8th Cu ₃ Mg ₃ Al ₂ CO ₃ (OH) ₁₆ ■ 4 H ₂ O 7.50 3.75 2.55 2.30 1.92 Ί, 54 1.49 9 Cu ₆ Al ₂ CO ₃ (OH) ₁₆ · 4 H ₂ O 7.50 3.75 2.62 2.57 2.28 1.92 1.71 1.61.1.53 1.49 10 Cu ₃ Zn ₃ Al ₂ CO ₃ (OH) _16-4 H ₂ O 7.60 3.75 2.62 2.56 ^ 2.28 1.94 i j 1.52 1.49 11th Ni ₃ Zn ₃ Al ₂ CO ₃ (OH) _16-4 H ₂ O 7.50 3.80 2.56 2.30 1.96! 1.75 j 1.52 1.49 12th Ni ₃ Mg ₃ Al Cr _{1-8 0-2} CO ₃ (OH) ₁₆ · 4 H ₂ O 7.65 3.80 2.60; 2.30 1.96 i 11.52 1.49 13th Feini) ₀ ^ ₁ Cr Al _{1-8 0-1} CO ₃ (OH) _16-4 H ₂ O

Examples 14-17

For the production of mixed crystals of the formula Co ₀₁₉ MiI _0-1 Mg ₅ AlaCO ₃ (OH) ₁₆ · 4 H ₄ O

the following solutions were made: Solution 1:

0.9 mole Co (NO _{s) 2} · 6 H ₂ O 0.1 "mole Mn (NOs) ₂ x 6 H ₂ O

5 moles of Mg (NOA) ₈ - 6 H ₈ O and 2 moles of Al (NOs) ₃ · 9 H ₂ O
dissolved in 12 liters of water

Solution 2:

1530 g (18.2 mol) of NaHCO ₃ dissolved in 12 liters of water

Both solutions were separated to about 95 °
heated and then solution 1 while stirring
added to solution 2 for 2 to 3 minutes. The he
Any precipitate is filtered off, with distillie

209537/5

washed tem water, for 20 hours at 150'C dried, then heated for 20 hours at 300 ⁰ C and finally reduced at 400 ⁰ C within 24 hours with hydrogen. The product thus obtained is a highly active hydrogenation catalyst. Mixed crystals of the formulas were analogous

₁ · 4 H ₂ O,

Co _{4 2} Cu ,. ₂ Mn _{0 e} Al ₂ CO ₃ (OH) ₁₆ · 4 H, 0 and
Co _e Al _lie Cr _0il cO ₃ (OH) _ie · 4 H ₂ O

10

precipitated and produced therefrom by calcining and subsequent reduction further valuable hydrogenation catalysts. The characteristic data of these catalysts and the corresponding data of some of the so-called full catalysts customary in industry are listed in Table 2. The mean crystallite size was determined radiographically from the half-width of the diffraction lines. What is particularly striking is the small crystallite size of the catalysts prepared according to the invention.

Table 2

Used for catalyst production Analysis of the contact before the reduction surface G) at Mixed crystals (Weight percent) (m ^s / redu game before Re adorns Co ₀₁₉ Mn ₀₄ Mg ₅ Al ₂ (CO ₃ ) (OH) ₁₆ · 4 H ₂ O Co 12.3; Mn 1.1; Al 13.0; Mg 19.1 duction 127.6 14th Co _{0, 5 l i0} Ni Cu _{0th 5} Mg _{4, 0} Al ₂ CO ₃ (OH) ₁₆ · 4 H ₈ O Co 6.0; Ni 11.7; Al 9.9; Mg 13.9; Cu 6.7 40.0 199.2 15th Co ₄₁₂ Cu ₁₁₂ Mn ₀₁₆ Al ₂ CO ₃ (OH) ₁₆ · 4 H ₂ O Co 42.0; Cu 13.7; Mn 3.3; Al 16.3 52.8 135.9 16 Co ₆ Al _li9 Cr _0il CO ₃ (OH) _ie 4 H ₂ O Co 56.1; Al 10.6; Cr 0.91 122.3 100.0 17th Comparison contacts 94.6 Co comparison contact Co 70; Mn 3.8 39.9 Co, C ü comparative catalyst Co 53; Cu 15; Mn 3.5 46.3 28.3 Co-precipitation catalyst on Al ₂ O ₃ as a support Co 38; Mn 4.0; Al (OH) ₃ 52.4 45.3 112.0 80.5

Table 2

example Pore volume of the oxidic contacts KPmacro Comparison contacts 0.11 0.17 Medium crystallite size 'Reduction yPmicro 0.19 0.13 0.17 (A) ( ⁰ C) 14th 0.09 0.11 0.26 0.20 about 85 400 ° C 15th 0.19 0.32 <90 400 ⁰ C 16 0.23 0.15 <90 40O = C 17th 0.18 85 40O ⁰ C 190 350 ° C 200 40O ⁰ C 220 35O ⁰ C

Example 18

The following solutions were prepared to produce a hydrogenation catalyst:

Solution 1:

5.5 moles Co (NOa) ₂ · _{6H 2} O

0.5 mol Mn (NO _{s) 2} - 6 H ₂ O

2MoI A1 (NO ₃ ) _S - 9 H ₂ O

dissolved in 12 liters of water Solution 2:

1530 g (18.2 moles) NaHCO ₃

dissolved in 12 liters of water

Both solutions were ^{heated separately to 90 °} C. and then solution 1 was added to solution 2 over the course of 3 minutes with stirring. The resulting reddish-violet precipitate was filtered off, washed with distilled water and treated for 24 hours 150 ° C dried. It consists of mixed crystals dei formula

Co ₅₁₅ Mn ₀₁₅ Al ₂ CO ₃ (OH) ₁₆ 4 H ₂ O,

the following rf values of the X-ray diffraction lines

have: 7.75; 3.88; 2.58; 2.30; 1.95; 1.53, 1.51 Å

The dried product was 20 hours

300 ⁰ C calcined, then crushed and nact

Addition of 2 percent by weight graphite to the cylinder

shaped particles with a diameter and a; Deformed height of about 3 mm. These have a bulk weight of 1.20 kg / liter and a total Settlement of 52.4 percent by weight cobalt, 3.9 percent by weight manganese and 9.0 percent by weight aluminum

minium.

The catalyst prepared in this way was reduced with hydrogen at 450 ° (48 hours. The internal surface area of the reduced contact is 60.3 m * / i

its mean crystalline size is 125 Å. 10 g of the reduced Contact was made under a nitrogen atmosphere with a mixture of 125 g of dioxane and 125 g Put nitrobenzene in a shaking autoclave. 100 atmospheres of hydrogen were injected at room temperature and the autoclave is heated to! 50 "C. The pressure in the autoclave rose to 134 atmospheres during heating and then fell steadily. Nacli 26 hours the attempt was canceled. The hydrogen pressure had dropped to 29 atmospheres. Analysis of the reaction mixture resulted in a conversion of nitrobenzene of 65.5%.

For comparison, a commercially available one known to be particularly effective was used in a further experiment Cobalt catalyst composition: 70 percent by weight Co, 3.8 percent by weight Mn, under otherwise completely tested under the same conditions. In this experiment, the pressure rose to 145 atmospheres during heating and had dropped to 58 atmospheres after 26 hours. An analysis of the reaction product showed a conversion ao of nitrobenzene of 60.7%.

The results show that the hydrogenation activity of the contact according to the invention is the high activity deb technical full contact exceeds, moreover is considerably more expensive to manufacture due to its 17.5% higher cobalt content.

Example 19

To produce a hydrogenation contact, the nickel as the active component, aluminum oxide as the carrier and Containing chromium (III) oxide as a recrystallization inhibitor, mixed crystals of the formula were used as the starting stage

Ni Al _{6 119 011} Cr CO ₃ (OH) ₁₆ · 4 H ₂ O

35

chosen.

The following solutions were prepared to precipitate these mixed crystals:
Solution 1:

2967 g (10.2 moles) Ni (NO _a ) "• 6 H" O
68 g (0.17 mol) Cr (NO,). I · 9H ₂ O
1213 g (3.22 mol) of Al _{(NO; i),} 9 · H ₂ O
dissolved in 20 liters of water
Solution 2:

2620g (31.2MoI) NaHCO ₁₁
dissolved in 20 liters of water

Both solutions were heated separately to 88.degree. C. and then solution 1 was added to solution 2 over the course of 3 minutes with stirring. The green Niderschlag formed was filtered, washed free of nitrate and dried at 150 ⁰ C.

The X-ray diagram of the mixed crystals shows rf values at 7.75; 3.88; 2.63; 2.58; 2.30; 1.96; 1.77; 1.66; 1.52; 1.49; 1.42; 1.30 A.

The dried product was ^{calcined at 300 °} C. for 20 hours, comminuted and, after adding 2 percent by weight of graphite, shaped into cylindrical particles with a diameter and a height of about 3 mm each. These have a composition of 53.2 percent by weight nickel, 10.1 percent by weight aluminum and 0.88 percent by weight chromium and a bulk density of 1.22 kg / liter.

A sample of this catalyst was reduced with hydrogen at 350 ° C. over a period of 24 hours. The inner surface of the reduced contact is 212.7 m ² / g, its mean crystallite size 40 A.

11.9 g of this reduced contact were placed under a nitrogen atmosphere with 125 g of dioxane and 125 g of nitrobenzene in a shaking autoclave and the autoclave was brought to 100 atmospheres with hydrogen in the cold state. The autoclave was then ^{heated to 100 °} C. and ^{shaken at 100 °} C. for 22 hours. During this time the pressure dropped to 50 atmospheres. An analysis of the reaction product showed a conversion of 57% of the nitrobenzene to aniline.

In a comparative experiment under otherwise identical conditions, Raney nickel showed a conversion only 56%.

2548

.- f «■

Claims (2)

Patent claims x and> 'the meaning given in claim 1 claims. ^ n mk ^ Provided that 2 (a + b + c + d) = u 1. Method of making active metal and 3 (x ~ ry) = 6 are,
oxides, active metals and active metal oxides or active metals and / or active metal oxides 5 '
and carrier material with a very fine distribution of the Catalysts containing active components The invention relates to a process for the production or catalyst carrier material with a large active area of catalysts with compared to the usual surface area by jointly dissolving at least one catalyst increased activity and life, at least one salt of a divalent and a trivalent io The production of in particular Carriers term metal in water, precipitation of the metals in the case of applied catalysts for the most varied of elevated temperatures in the form of basic carbonate purposes is known and laid down in many publications and / or uniform mixed crystals and an-. For example, reference is made to the standard thermal or thermal and marriage works by GM Schwab, Handbuch der Katamische treatment der Abällungsprodukte, Dalyse, Vol. 5, S. 424ff., And PH E mme tt, Catalysis, characterized by that one the vol. 1. part 1, p. 224ff. and 315ff., referenced.
Salts of bivalent and trivalent metals in aqueous In general, one of the following options of formula I is used in the preparation, even if the solution is mixed in a ratio that corresponds to the Ka- in many variations. KMe. Ni (II) ₆ COdDrCu (II) ,, Zn, Mn (H), ^{20 L} Mechanical mixing of carrier and t - '/ mxv, Ai ^ ,,,, v r- ,,,, "v" ", active components by grinding, kneading Fe (II) ₉ ) <A1 _X Cr (III) ₁ , Fe (III) ₂ )] '^ I _{od ä and subsequent} shaping and activity corresponds, in the fourth by thermal or chemical o, b, c and d for whole numbers or decimal numbers. from O to 6, Sz 2. Impregnation of a given, given e for a whole number or a decimal - if already formed carrier material with (non-) number from 0 to 4, aqueous solutions of easily decomposable salts or / and g for O or decimal numbers from 0 to 0.5, complexes of the active components and then and y for whole numbers or decimal numbers ßende thermal decomposition and / or chemical from 0 to 2.0 30 activation, and ζ for an integer or a decimal 3. Chemical precipitation of the active components number from 0 to 1, together with or in the presence of not yet with the proviso that 2 (a ± b + · ■ · g) = 12 and shaped T; 3 (x + y + z) = 6, with an aqueous solution more intensive mixing of all components of an alkali hydrogen carbonate, which has a surplus than that described under 1 and 2 shot up to 20 percent by weight alkali hydrogen process. carbonate, based on the required for precipitation This subheading also includes, in principle, the process that theoretical amount of bicarbonate is described in U.S. Patent 3,396,124. a temperature of 50 to 100 ° C basic According to the teaching of this patent are aqueous Carbonates 40 solutions of nitrates of bivalent and trivalent metals [Me ²⁺ Me ³ '] (OH) -CO -4HO, in particular nickel and aluminum ie 3 2 _sa j _{ze used to convert} these solutions with bicarbonate and / or basic carbonates, those of the mixed nates, mixed precipitations of hydroxides, carbonates crystal series of the formula II or hydroxydcarbonates of the 2- and 3-valent KMg _n Ni (II) ₆ Co (II) ,. Cu (II), Zn, Mn (II), «to produce metals (see column 1, lines 69 to 72). Fe (II) ₁₇ ) <AWTr (III) _lf Fe (IIl) ₂ )] ^Übe ; ^{the implementation of} the fall are not rn rntn & u η to find special information; from the examples LU ₃ (UH) ₁₈ ^ H ₂ U, however, it can be seen that the molar ratios of obey, fail, in which Me * ⁺ / Me ³ * in solution are consistently less than 1, a, b, c and d for whole numbers or decimal numbers 50 so that no defined individual compounds or from 0 to 6, mixed crystals arise and always a mixture of many χ and y for integers or decimal numbers get connections next to each other at the same time from 0 to 2 stand and will. e, /, g and ζ the meaning given above According to all methods mentioned and similar have, 55 although catalysts are obtained with more satisfactory with the proviso that 2 (a + b + ■ · · g) = 12 and / or good initial activity, but whose activity is 3 (x - \ - y + z) = 6, the obtained uniforms more or less quickly, often already within basic carbonates and / or mixed crystals dry a few weeks, to the extent that an exchange is net and calcined and reduced. the catalysts is necessary. To a big one 2. The method according to claim 1, characterized in part, this loss of activity is due to indicates that the catalysts or that the first in the form of the smallest crystallites before catalyst support material by calcining or lying active components under the reaction calcining and reducing a basic car condition, especially under the influence of higher bonates, which combines the formula 111 temperatures to form larger crisis units. _{r /} .. χ, · ,,,, ^ .... ,, ....,., ",,,, _xs , ⁶ 5 menwachsen. which naturally results in a reduction in the rn ^ nuV '"^ η ^{1 () (} ' ^{W lrCr (111)} " ^] active surface and thus a reduction in the (CU ₃ ) (UH) ₁₁₁ · 4 H ₂ U means activity.