DE2429293A1 - CATALYSTS AND THEIR USE FOR HYDROGENATION - Google Patents

Description

The invention relates to exsene catalysts and their use on hydrogenation reactions / specifically on the hydrogenation of organic compounds, in particular of nitriles to amines.

It has already been proposed to use iron catalysts in the hydrogenation of nitriles, especially adiponitrile, either partially to use aminocapronitrile or completely to hexamethylenediamine. DT-PS 848 654 describes the hydrogenation of Adiponitrile in the presence of toluene and liquid ammonia 85 C with formation of aminocapronitrile and a small amount of hexamethylenediamine using an iron catalyst that precipitated on pumice and reduced at 350 ° C. the

v / u ■ - ■ ■ ■ 509812/0983

GB-PS 728 599 relates to the catalytic hydrogenation of nitriles to amines / in particular of adiponitrile to hexamethylenediamine, using a hydrogenating gas containing carbon monoxide in an amount of 10 to 200 parts by volume per million parts of hydrogen. Particularly suitable hydrogenation catalysts are those which are known or suspected to form carbonyls, including iron, during the reaction. GB-PS 894 751 relates, inter alia, to the hydrogenation of compounds which contain nitrogen-containing groups which can be reducible to amino groups, including nitriles and in particular adiponitrile, in the presence of a metal hydrogenation catalyst which was sintered before the hydrogenation. Iron is one of the particularly suitable catalyst metals. The metal compounds - usually in the form of their oxides - are treated with hydrogen at 250 to 600 ° C. after sintering until the oxide is practically completely reduced to the metal. GB-PS 1 123 530 describes the use of a 100% Fe ₃ O ₄ catalyst for the hydrogenation of "adiponitrile to hexamethylenediamine. GB-PS 1 317 464 relates to the catalytic hydrogenation of adiponitrile to hexamethylenediamine by adding adiponitrile, Ammonia and hydrogen in the supercritical vapor phase are fed to a reactor which is operated at 100 to 200 ° C under excess pressure and contains a granular catalyst made of an iron compound, which was ^{activated by contact with hydrogen at a temperature of up to 600 0} C and which under the Catalytic hydrogenation conditions are reduced to metallic iron.

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FR-PS 2 119 621 describes a similar process in which, however, the iron compound is activated in the presence of hydrogen containing 0.001 to 10% by volume of ammonia.

Hexamethylene diamine is a valuable intermediate and is mainly used for the polycondensation with dicarboxylic acids to form polyamides, especially with adipic acid to form hexamethylene adipamide (nylon 6,6). A high purity of the polyamides is very desirable, especially when the polyamides are spun from the melt into fibers, as is often the case with nylon 6,6. This means that the intermediates from which the polyamides are made must also be as pure as possible. Impurities in hexamethylenediamine for use in fiber grade polyamides can only be tolerated in very small proportions. The usual method of purifying hexamethylenediamine is by fractional distillation. However, since the impurities often have boiling points close to that of the hexamethylenediamine itself, efficient fractionating columns with a large number of theoretical plates are necessary to achieve effective separation. Such a cleaning system is expensive to install and operate. In addition, the size of the equipment required, and therefore its cost, increases as the proportion of contamination to be removed increases. ¹ It is therefore desirable to keep the impurity formed during the hydrogenation of adiponitrile as low as possible.

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In addition, the increase in the level of contaminants naturally limits the amount of raw material that can be removed from an existing cleaning plant can be enforced.

When using an iron catalyst for the hydrogenation of adiponitrile it has now been found that when using special Iron catalysts, the content of impurities in the hexamethylenediamine obtained can be regulated very advantageously.

According to the invention, a particularly suitable catalyst composition for hydrogenating organic compounds is a molten one and solidified iron oxide in the form of particles for use in a fixed catalyst bed are suitable, with the molten material not less than 96.5% iron oxide with a Oxygen to iron atomic ratio in the range 1.2: 1 to 1.4: 1.

Preferably the molten material contains no less than 97.5% iron oxide. The atomic ratio of oxygen to Iron in the iron oxide of the molten and solidified material is preferably in the range of 1.30: 1 to 1.39: 1. A A ratio of about 1.33: 1 corresponding to the composition of the magnetite is particularly useful, but ratios of this value up to 1.37: 1 is also particularly suitable. Desirably the molten and solidified iron oxide is essentially free from hematite. For this purpose, reference is made to the phase diagram of the iron-iron oxide-oxygen system, such as

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for example is given by L.S. Darken and R.W. Gurry in Journal of the American Chemical Society, Volume 68 (1946) S-. 799. Advantageously, it has melted and solidified Iron oxide the crystal structure of a spinel,

The composition of the molten material can be controlled by viewing the composition of the feed * the melting level is regulated. Melting can be done, for example, electrothermally with the help of electrodes, especially iron electrodes, which are used in the material to be melted. Melting takes place at temperatures above about 138O ° C; temperatures of up to 1600 ° C. and above can be used depending on the composition of the charge. When iron electrodes are used, they can partially melt and enter the molten material and so its composition influence. The composition of the molten material can also be adjusted to some extent by controlling the oxygen content the atmosphere in the melting vessel can be controlled.

The material fed to the melting stage is an iron oxide or a mixture of iron oxides or a mixture of an iron oxide and metallic iron. A particularly suitable feed is a magnetite, especially a naturally occurring one Magnetite ore. A Swedish magnetite ore with a high enough iron oxide content to be a molten material with no less than 96.5% iron oxide is a very suitable feed material. It is preferable to add the feed

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no additives other than iron oxide or iron, in which these iron oxides are, for example, during or before melting differ from those used in the production of ammonia synthesis catalysts to which promoters are added.

The molten material is allowed to solidify. It is then ground and sieved to the appropriate particle size range. The appropriate grain size range depends on the way in which the catalyst is used. When he's as stationary Catalyst is used, through which the hydrogen gas and the to be hydrogenated Material flowing, as is customary in the hydrogenation of adiponitrile, is generally a material in the size range from 0.75 mm to 6.0 mm, preferably from 1.02 mm to 3.0 mm and in particular from 1.4 mm to 3.0 mm are suitable.

Before use, the catalyst composition according to the invention is activated by adding at least part of the iron oxide by heating to a temperature above 200 ° C, but not above 600 ° C, in the presence of hydrogen to metallic iron is reduced. Preferably activation continues until at least 85% by weight of the available oxygen in the iron was removed. Activation can continue until essentially all of the oxygen, for example 95 to 98% of available oxygen has been removed. During the activation, it is desirable for the water vapor formed to diffuse back to prevent.

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If desired, the one used for activation can be used Hydrogen contain a proportion of ammonia. For example, the hydrogen used for activation can be 0.25 to 25 Contains% ammonia by volume. At the temperatures used and in the presence of the activated catalyst, part of the Ammonia split into nitrogen and hydrogen, so that the ammonia portion in the de.n activation tank leaving Hydrogen is lower than in the entering hydrogen. However, at pressures above about 3 atmospheres, the proportion is of the split ammonia is less than 5%. Activation in the presence of ammonia generally results in a more active one Catalyst with a larger surface.

A preferred activation temperature is in the range from 250 to 500 ° C. Activation pressure is not critical. the Activation can be at atmospheric pressure or below if desired overprint, for example when printing up to 15 Atmospheres or even at pressures as high as 500 atmospheres.

The activity of the catalyst influences the speed with which the adiponitrile is hydrogenated. Although not necessarily aimed at the highest activity in every case must be, since the rate of hydrogenation of the adiponitrile can be limited by other factors, is the measure of the activity adjustable. The degree of activity of the catalyst depends in the first place on the proportion of that available in the iron oxide Oxygen removed during activation. Before-

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preferably at least 85% by weight of the available oxygen is removed, and in particular substantially all of the oxygen, i.e. at least 95% by weight removed. Secondly, however, the activity of the catalyst depends on its surface area away. If surface enlargement is desired, it can be achieved in a number of ways.

As already indicated, a proportion of ammonia in the activation hydrogen results in a more active catalyst with a larger surface. It has been found that the ammonia content is at least 1.5% by volume for optimum effect target. A higher proportion above this value does not have a very significant effect, but it is also not disadvantageous. if Ammonia is used, its proportion in the supplied activation hydrogen is preferably in the range from 1.5 to 15 volume%.

The proportion of water in the activation hydrogen should be be kept low. Since water is formed during the reduction of the iron oxide, it is necessary when circulating the activating hydrogen to condense it out first to cool the water vapor and then to warm it up again to the activation temperature. When the activation hydrogen is supplied contains too high a proportion of water in addition to the heated catalyst, the highest degree of oxide reduction cannot be achieved and the surface area of the activated catalyst is limited. It has been found that for the highest catalyst ac-

hours that door d

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tivity of the water content in the activated hydrogen less than 1% by volume, preferably less than 0.5% by volume, should be.

Within the described temperature limits, the temperature does not influence the achievable degree of reduction of the oxide, provided there is sufficient time; however, the rate of activation increases with temperature. A rise in temperature also leads to a decrease in the catalyst surface area; the activation temperature is used to achieve the highest activity preferably in the absence of ammonia to a range from 275 to 325 ° C and in the presence of ammonia to a range limited from 325 to 375 ° C. On the other hand, these temperature ranges lead to fairly low activation rates, and in practice, considerably higher temperature ranges will be preferred in order to achieve a higher rate of activation to achieve with a certain loss of catalyst surface.

Wennudie rate at which the activation of hydrogen is passed over the catalyst is increased _/ also increases the rate of activation, but without affecting the degree of reduction of the oxide, which eventually can be achieved. However, the surface area of the catalyst also increases when the flow rate of the activating gas increases. It has been found that, in order to achieve a high surface area, the flow rate of the activating hydrogen

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At least 7.5 ml per minute and gram of catalyst oxide, preferably at least 15 ml per minute and gram and in particular 15 to
Should be 25 ml per minute and gram. For example, the rather slow activation rate due to the limitation of the activation temperature required for a large surface area by a
high circulation rate of activation hydrogen
compensated.

In practice, however, the rate of circulation is
limited by restrictions on the investment, and in the event of such
Limitation, the activation speed may be too low at the optimal temperatures. It has been found that under such circumstances the catalyst will perform in acceptable times (2-3
Weeks) is activated in a satisfactory manner if ammonia-containing activation hydrogen is used at circulation rates of 2.5 to 7.5 ml per minute and gram of catalyst oxide
and uses temperatures from 375 to 425 ° C.

The activated catalysts of the invention have in general

2 mean a surface area of 4 to 25 m / g.

The activated catalyst is generally in air
Pyrophoric and must therefore with the exclusion of oxygen, e.g. in
under a nitrogen atmosphere to the container in which it is to be used. Alternatively, however, the activated catalyst can, for example, by treatment with a gas with low

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Oxygen content, e.g. air diluted with nitrogen, stabilized which creates a superficial layer of oxide on the catalyst and does not render the catalyst pyrophoric will. Such a stabilized activated catalyst can be easily stored and transported; can be used its activity can be restored very quickly by brief hydrogen treatment.

When used for the hydrogenation of organic compounds, the activated catalysts of the invention can, for example filled into a suitable container and then with hydrogen and the compound to be hydrogenated, if desired in Presence of a solvent or other additive, be contacted by conveniently flowing a mixture of these materials through a catalyst bed. at Use for the hydrogenation of adiponitrile, the activated catalyst according to the invention is preferably used in a fixed bed. Hydrogen is normally used in excess of the amount required for reduction to hexamethylenediamine is used and the excess can be recycled or recovered for reuse. It is also preferred that Hydrogenation in the presence of ammonia, preferably from 2 to 10 parts by weight of ammonia per part by weight of adiponitrile, to be carried out. There Ammonia does not take part in the reaction, it will if desired recycled or recovered for reuse. As is known with the use of iron catalysts, the Proportion of water below, the reaction participant η low

are kept, expediently below 0.2 wt .-% and preferably less than 0.1% by weight.

The hydrogenation of adiponitrile using the invention activated catalyst takes place, for example, at temperatures in the range from 80 to 200 C. The hydrogenation is carried out under pressure, for example at a pressure in the range of 20 to 500 atmospheres, preferably in the range from 200 to 400 atmospheres. The process is preferably operated continuously and the excess of hydrogen and Ammonia recycled. For this purpose, the activated catalyst can be contained in a suitable pressure vessel through which the Reaction mixture is passed. The catalyst can be in the reactor activated in situ, or it can be activated in a separate container and then transferred to the reactor. in the In the latter case, the catalyst is preferably contained in a cartridge or other suitable container so that the activated catalyst can be quickly transferred into the reactor without contact with air.

In the case of continuous operation, the temperature of the catalyst bed can vary depending on the feed rate of the adiponitrile. The temperature of the hottest part of the Bettes (hot spot), for example, can range from 130 to 180 ° C and can be varied by controlling the feed rate can be adjusted to the desired temperature. The inlet temperatures of the reaction mixture can be much lower

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be / for example from 90 C upwards.

In the case of hydrogenations with the activated catalyst according to the invention, the outflowing reaction mixture is broken down into its constituents separated and recovered the hydrogenated product in the usual way. In the hydrogenation of adiponitrile, the reaction mixture is Hexamethylenediamine is separated into gaseous and liquid components for the recovery of hydrogen and ammonia isolated and known by rectification or otherwise Way separated from the impurities.

When using the catalyst of the invention for the hydrogenation of adiponitrile, it is of advantage / that in the obtained hexamethylenediamine a particularly low content of impurities is achieved before any purification. In particular a lower content of the impurity diaminocyclohexane is achieved when using other activated iron catalysts compares / for example with an activated iron oxide naturally occurring in Labrador, which mainly consists of hematite consists. .

Diaminocyclohexene is a very undesirable contaminant in hexamethylene diamine, when the latter is used to make polyamides such as hexamethylene adipamia, as it causes discoloration of the polyamide and thus the fibers spun from these polyamides. In addition, the presence of Diaminocyclohexane as an impurity also causes difficulties

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the spinning of these polyamides into fibers. For these reasons, the content of diaminocyclohexane in hexamethylenediamine for polyamide production must be kept very low, suitably below 25 ppm, and to achieve this one must Cleaning system installed and operated. The purification usually consists of a fractional distillation Diaminocyclohexane and hexamethylene diamine boiling points close together are costly and efficient fractionation columns with a large number of theoretical trays required. The size of the cleaning system and therefore its costs necessarily increase with the proportion of diaminocyclohexane in the hexamethylenediamine initially produced. Hence there has been a reduction the dianinocyclohecan content in the crude hexamethylenediamine a fraction of a percent already has a significant impact on the production costs of purified hexamethylenediamine with low diaminocyclohexane contents, as required for polymer production.

When operating the one described above for adiponitrile hydrogenation Process has been found that the proportion of diaminocyclohexane increases in the hexamethylenediamine obtained, as the temperature of the catalyst bed increases. To get a good adiponitrile throughput rate in the catalyst bed achieve, for example, throughputs of at least 0.4 kg adiponitrile per hour and kg catalyst oxide, the catalyst bed preferably operated at a temperature (hot spot) of at least 130 ° C. The proportion of diaminocyclohexane formed

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is used when operating at these. Temperatures to a minimum decreased when the weight ratio of ammonia to adiponitrile in the feed is at least 3.5: 1.

Accordingly, the invention provides a process for the hydrogenation of adiponitrile to hexamethylenediamine in the presence of a
activated iron catalyst at a catalyst bed temperature (hot spot) of at least 130 ° C in the presence of at least 3.5 parts by weight of ammonia per 1 part of Ädiponitril in the charge, the catalyst obtained by activating a molten and solidified iron oxide as defined above
became.

Because the use of more ammonia than necessary because of the larger costs for the procurement, recovery and recycling of the excess ammonia is wasteful, the invention becomes Process preferably in the presence of 5.3 to 5.8 parts by weight of ammonia per part by weight of adiponitrile in the feedstock operated.

The invention is illustrated but not limited by the following examples.

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example 1

A Swedish magnetite ore made from 98.47% by weight of iron oxide was melted at a temperature of 1590 ° C for one hour. After the molten material had solidified, it was crushed, so that all of the material was less than 3 mm and 99.6% by weight was greater than 1.4 mm. The molten material has the following composition:

Total iron content *: 70.7% divalent iron: 19.9%

trivalent iron: 50.8%

Iron oxide: 98.2%

Aluminum oxide (Al ₂ O ₃ ): 0.2%

Silicon dioxide (SiO "): 0.5%

Calcium Oxide (CaO): 0.1%

Vanadium pentoxide (V ₂ O ₅ ): 0.2%

Atomic ratio oxygen: iron: 1.36: 1 The molten and crushed material was heated to 350 ° C for 3 hours under nitrogen and then heated to 450 ° C while hydrogen was passing for 48 hours at a rate of 10 ml per minute per gram of sample the material was passed. After cooling under nitrogen, the activated catalyst was used to hydrogenate adiponitrile as follows. A mixture of adiponitrile and 5 times the amount by weight of ammonia was at a rate of about 0.136 kg / h, together with hydrogen at a rate from 0.099 to 0, ^ ³ Nm / h over a sample

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from 0.453 kg of catalyst passed. The inlet temperature on
Catalyst bed was 93 to 98 ° C and the exit temperature 94 to 104 ° C. The resulting product contained 98.22% hexamethylene diamine and 0.19% diaminocyclohexane.

Example 2

Comparative example

A Labrador Hematite Ore 'that is smaller in its entirety was than 3 mm and of which 99.2% by weight was larger than 1.02 mm had the following composition.

Total iron content: 68.4%

divalent iron: 0.7%

trivalent iron: 67.7%

Iron oxide: 97.7%

Aluminum oxide (Al-O ₃ ): 0.2%

Silicon dioxide (SiO-): 1.5%

Calcium Oxide (CaO): 0.2%

Vanadium pentoxide (V ₀ O ₁ -) _a ':

Atomic ratio of oxygen: iron: 1.49: 1
The ore was activated with hydrogen and then used to hydrogenate adiponitrile in the manner described in Example 1. The resulting product contained 98.05% hexamethylenediamine and 0.35% diaminocyclohexane.

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Example 3

The molten and crushed Swedish magnetite ore used in Example 1 was obtained by heating it to a temperature activated in the range of 320 to 420 C, with hydrogen with 1 to 3 volume% ammonia for 50 hours at one rate of about 1.375 Nm / h'kg of catalyst oxide was passed through. The catalyst was heated to temperature under nitrogen brought and cooled to below 100 ° C under hydrogen and then flushed with nitrogen. 86% of the oxygen available in the iron had been removed.

The activated catalyst was used to hydrogenate adiponitrile. Adiponitrile was mixed with about his 6 times the amount by weight of ammonia at a rate of about 0.5 kg of adiponitrile per hour and kg of catalyst oxide together with Hydrogen at a rate of 1.44 Nm / h «kg catalyst passed over the catalyst. The inlet temperature on Catalyst bed was 99 to 113 C and the highest temperature (hot spot) 150 to 160 ° C. The resulting product contained 99.14% hexamethylenediamine and 0.23% diaminocyclohexane.

Example 4

Comparative example

The Labrador hematite ore used in Example 2 was activated and in the manner described in Example 3 for the

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Hydrogenation of adiponitrile used. The product obtained contained 98.51% hexamethylene diamine and 0.42% diaminocyclohexane.

Example 5

The molten magnetite ore described in Example 1 was at a Prescribed Temperature during a Prescribed Activated time using a prescribed activation gas. The loss of face, the catalyst and its surface area after activation was measured using nitrogen adsorption for the surface measurement. the Results are given in Tables 1 to 4 below.

Table 1

Effect of ammonia in the activating hydrogen. Temperature: 450 ° C
Time: 48 hours. Gas velocity: 10 ml / min · g of catalyst oxide

Ammonia concentration
in the activation
gas Vo | .-%. $ '( Weight loss des
Catalyst
Wt% Surface of the acti
fourth catalyst
m ² / g 0 27.35 7.08 1.5 27.46 12.68 3.0 27.25 14.54 '6.0 27.30 13.90 8.0 27.19 14.00 12.0 19812/0983
27.31 15.16

Table 2

Effect of the water in the activator Temperature: 450 ° C
Time: 48 hours

Water conc. ^
in the actii
Vol% \ mmonia conc.
/ ating gas
Vol% Weight loss
of the catalyst
Wt% Surface of the
activated Ka
talysators
m ² / g 2.9 0 24.38 5.03 0.9 0 26.77 6.82 0.3 0 27.35 6.50 0.0 0 27.42 6.81 2.9 .3 24.41 10.26 0.9 3 27.27 11, 19 0.3 3 27.35 15.23 0.0 3 27.37 14.78

Table 3A

Effect of temperature <ier activation Gas velocity: 20 ml / min · g catalyst oxide Activating gas: hydrogen

Temp.
° C Time
hours Weight loss des
Catalyst weight% Surface of the acti
fourth catalyst
m ² / g 300 336 27.04 13.05 350 64 27.09 11.17 400
450 72
24 27.50
% W8 12/096 3 9.01
7.42

Table 3B

Effect of the activation temperature. Gas velocity: 20 ml / min · g catalyst oxide. Activation gas: hydrogen + 3% by volume of ammonia

Temp.
° C Time
hours Weight loss des
Catalyst weight% Surface of the acti
fourth catalyst
m ² / g 300 672 26.72 21.48 350 117 26.69 22.99 400 70 27.32 19.19 450 24 26.36 15.33

Table 4A

Effect of the speed of the activation gas Activation gas: Vihydrogen

Temp. 350 Gas speed Time Weight loss Surface of the ° r speed ml / min · g hours of the catalyst activated Catalyst oxide Wt% Catalyst 400 m2 / g 5 298 26.96 9.90 10 249 26.98 10.48 450 20th 64 27.09 11.17 5 151 27.20 7.36 10 118 27.36 8.18 20th 72 27.50 9.01 5 96 27.12 6.07 10 48 27.35 7.08 20th 24 27.36 7.42

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Table 4B

Effect of the speed of the activation gas Activation gas: hydrogen + 3% by volume of ammonia

Temp. Gas speed Time Weight loss Surface of the ⁰ C speed ml / min · g hours of the catalyst activated Catalyst oxide Wt% Catalyst
m2 / g 350 5 600 26.84 13.31 10 240 26.23 19.73 20th 117 26.69 22.99 400 5 162 26.90 13.98 10 110 27.11 16.13 20th 70 27.32 19.19 450 5 96 27.16 13.91 10 48 27.25 14.54 20th 24 27.36 15.33

Example 6

The molten and crushed magnetic magnetite ore described in Example 1 was obtained by heating to a temperature heated in the range of 360 to 412 ° C and thereby hydrogen with 11.8% by volume of ammonia under a pressure of 4.2 atmospheres 213 Hours at a rate of about 0.813 Nm / h »kg of catalyst oxide was passed through. The following table 5 gives the ratio of ammonia to adiponitrile for consecutive days, the rates of adiponitrile and hydrogen feed, the temperature of the catalyst bed (hot spot) and the Share of diaminocyclohexane in the resulting hexamethylenedi-

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amine. The reactants were using the catalyst bed 105 ° C supplied; the operating pressure was 250 atmospheres.

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cn o co

ro

co er »co

Day
No. Weight ratio
nis
Ammonia: adipo-
nitrile Adiponitrile
feed speed
age
kg / h kg cataly
carbon dioxide hydrogen
Nm ³ / h «kg
Catal
toroxide catalyst
bed temperature
(hot spot)
⁰ C Diaminocyclohexane J.
in the product
lenediamine wt .-% 1 4.69 0.48 1.375 163 0.30 2 4.81 0.46 1.44 162 0.28 3 4.60 0.49 1.56 158 0.25 4th 4.73 0.48 1.56 159 0.28 5 4.84 0.46 1.56 157 0.31 j
C. 6th 4.94 0.45 1, 50 158 0.26 7th 5.35 O, 43 1.50 156 0.23 8th 5.59 0.44 1.44 157 0.23 9 5.36 0.46 1.44 152 0.23 10 5.46 0.45 1.44 151 0.21
i

X ι

S-

-C

CO NJ CD CO

Claims (1)

Claims 1. Iron catalyst mass for hydrogenation of organic Compounds, characterized in that they consist of a molten and solidified iron oxide in the form of a fixed catalyst bed suitable particles, the molten material being not less than 96.5% iron oxide by atomic ratio of oxygen: contains iron in the range 1.2: 1 to 1.4: 1. 2. Catalyst composition according to claim 1, characterized in that it was obtained by melting magnetite. 3. A method for producing an activated iron catalyst by heating an iron compound in the presence of Hydrogen to a temperature above 20 ° C, but not above 600 C, characterized in that the iron compound is a molten and solidified iron oxide in the form of particles suitable for a fixed catalyst bed, the molten Material not less than 96.5% iron oxide with an atomic ratio of oxygen to iron in the range 1.2: 1 to 1.4: 1 contains. 4. The method according to claim 3, characterized in that at least 85%, preferably at least 9 5% of the in the Iron oxide removed from available oxygen. 5098 12/0 963 5. The method according to claims 3 or 4, characterized in that that a hydrogen is used for the activation which contains 1.5 to 15% by volume of ammonia. 6. The method according to claim 3 or 4 with an ammonia-containing activating hydrogen, characterized in that that the activation temperature is 275 to 325 C, the activation hydrogen Contains less than 1% by volume of water and at a rate of at least 7.5 ml / min · g of catalyst oxide is passed over the catalyst. 7. The method according to any one of claims 3 to 5, characterized characterized in that the activation temperature is 325 to 375 C and the activation hydrogen is less than 1 vol .-% Contains water and is passed over the catalyst at a rate of at least 7.5 ml / min »g of catalyst oxide. 8. The method according to claim 5, characterized in that the activation temperature is 375 to 425 ° C and the Activation hydrogen at a rate of 2.5 to 7.5 ml / min-g of catalyst oxide is passed over the catalyst. 9. Use of the according to a method of claims 3 to 8 prepared catalyst for the hydrogenation of organic compounds with hydrogen. 509812/0963 10. Use according to claim 9 for the hydrogenation of adiponitrile to hexamethylenediamine by heating adiponitrile in the presence of the catalyst in a fixed bed and in the presence of excess hydrogen and ammonia under pressure at a elevated temperature at which the hot spot of the catalyst is in the temperature range 130 to 180 ° C. 11. Use according to claim 10, characterized in that that the catalyst at least 5.3 parts by weight of ammonia each 1 part adiponitrile supplies. 509812/0963 ORIGINAL INSPECTED