DE1224711B - Process for the activation and regeneration of aluminum halide carrier catalysts - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

BOIj

German KL: 12 g - 11/80

Number: 1224 711

File number: St 18102IV a / 12 g

Filing date: July 21, 1961

Opening day: September 15, 1966

Aluminum halides are often used as so-called solid catalysts, whereby Aluminum halide is on the surface of particles of an adsorbent material such as bauxite. These solid aluminum halide adsorbent catalysts are used in particular there where continuous work is desired. For example, in the isomerization of η-butane in on an industrial scale, a catalyst is used, which consists of aluminum trichloride on activated bauxite of a particle size corresponding to sieve openings of about 4.7 to 2.36 mm.

The solid catalysts consisting of aluminum halide and adsorbent lose during the course of the reaction in effectiveness and are eventually discarded when the effectiveness of the used Catalyst has reached a value at which its further use is uneconomical. Aluminum halides are expensive materials, and often the adsorbents are even more expensive.

The attempts so far made to develop processes after which the used catalyst transferred back to a higher active state, d. H. can be regenerated, do not have to Success led.

It is known to remove the used catalyst from aluminum chloride by washing with an aqueous alkali solution to free, to wash the then present carrier neutral and at temperatures of about 300 ° C to activate and to impregnate the regenerated carrier with vaporous aluminum chloride. This process is cumbersome and because of the necessary dismantling of the catalyst Associated losses in the active ingredient.

A process for the activation of fresh and for the regeneration of used catalysts consisting essentially only of aluminum halide located on a solid adsorbent has been found, which is characterized in that the fresh catalyst or the catalyst used in a hydrocarbon conversion process is added with gases containing hydrogen 65 to 316 ° C treated under a hydrogen partial pressure of at least 7 kg / cm ² until its activity for the respective hydrocarbon conversion has risen considerably above the initial value. The hydrogen gases used preferably contain a hydrogen halide which corresponds to the halogen present in the catalyst. A hydrogen partial pressure of 14 to 210 kg / cm ² is preferably maintained.

Procedure for activation and regeneration
of supported aluminum halide catalysts

Applicant:

Standard Oil Company, Chicago, JIl. (V. St. A.)

Representative:

Dr. IM Maas, patent attorney,
Munich 23, Ungererstr. 25th

Named as inventor:

William Schoen, Houston, Tex .;

John Andrew Ridgway, Jr., La Port, Ind .;

Clifton Norton Sechrist,

Texas City, Tex. (V. St. A.)

Claimed priority:
V. St. v. America of July 27, 1960 (45 541),
of July 28, 1960 (45 815) ■

A used catalyst is to be understood as meaning a catalyst which is less catalytic Has effectiveness as a fresh catalyst of this type, the loss of activity due to the Use in a process for the conversion of a hydrocarbon has occurred. The used one Catalyst can be derived from any of the processes in which a hydrocarbon feed and which are catalyzed by aluminum halides, in particular by solid catalysts of the type defined below. Those from conversions with saturated hydrocarbons used catalysts derived from the regeneration process according to the invention particularly accessible. A preferred starting material is a catalyst used in the Isomerization of paraffins and low molecular weight cycloparaffins was used, in particular of paraffinic hydrocarbons with 4 to 8 carbon atoms and cycloparaffins with 6 up to 9 carbon atoms that can be rearranged. Some isomerization processes require the presence of a cycloparaffin inhibitor, in which case the hydrocarbon feed is not only the called paraffins with low molecular weight, but also cycloparaffins with 5 to 9 carbon atoms may contain. Used catalysts

609 660/409

from the isomerization of η-butane, n-pentane and η-hexane are the preferred starting materials for the regeneration processes according to the invention.

It should be noted that the regeneration process according to the invention is based on catalysts of the specified type can be used, which have lost part of their catalytic effectiveness, and that their regeneration consists only in a partial restoration of this lost activity can. When a catalytic converter is considered used or exhausted is not just one Question of his ability to catalyze implementation, but also a question of economic Considerations. It may seem desirable to have a still fairly effective catalyst again practically to bring the activity of the fresh catalyst, instead of the catalyst up to a very a much lower level of activity and then bring it to an activity that is below the of the fresh catalyst lies. It should also be noted that some spent catalysts cannot be brought back to their full effectiveness. The nature of the procedure, the nature of the the respective halides and the type of supported cocatalyst all have an influence on the regenerability of the spent catalyst.

According to the invention, a hydrogen partial pressure of 14 to 210 kg / cm ³ is preferably maintained. The time of the treatment according to the invention with the hydrogen gas has an influence on the extent to which the catalyst activity is restored. As already mentioned, it is possible that a certain catalyst cannot be brought back to the full activity of the fresh catalyst, so that the continuation of the treatment beyond this point of the highest regained activity is ineffective. The treatment time depends in particular on the type of catalyst used and the conversion process from which the used catalyst originates.

Regeneration can be achieved using gaseous hydrogen alone. Be it pointed out that under the designation hydrogen-containing gases or "hydrogen gas" both pure hydrogen and hydrogen, is understood, the inert gaseous diluent, such as nitrogen, methane, ethane and other gases that contain neither aluminum nor halide attack the adsorbent material. A better regeneration or an equally good regeneration under less severe conditions is achieved when a hydrogen halide is present in the stream of hydrogen gases is present. This hydrogen halide preferably corresponds to that in the spent catalyst contained halogen. So is the hydrogen halide when aluminum chloride is the aluminum halide is, preferably hydrogen chloride.

If the adsorbing material is a cocatalyst based on aluminum oxide - this designation is explained in more detail below - then particularly favorable results are achieved if the regeneration is carried out at a temperature of about 93 to 232 ° C and a hydrogen partial pressure of about 14 kg / cm ^{2 is} carried out. For this material, 56 kg / cm ^{2 is} usually a sufficient upper hydrogen pressure. Depending on the condition of the used catalyst, the type of aluminum oxide base and the desired degree of restoration of activity, the treatment time varies between a fraction of an hour and several days. Substantial restoration of activity is achieved under these temperature and pressure conditions in as short a time as 6 hours. Periods of e.g. B. 72 hours usually lead to a regenerated catalyst which has about the same activity as fresh catalyst.

ίο Is the adsorbent material a cocatalyst? based on aluminum oxide, the hydrogen halide, if one is used, makes it is about 0.1 to 15 percent by volume of the total treatment gas. Larger amounts of hydrogen halide may be present but generally increase the efficiency of the regeneration not. In the case of aluminum chloride as the halide, the gaseous hydrogen contains hydrogen chloride in an amount of about 0.1 to 10 percent by volume

ao and in most cases about 0.5 to 5 percent by volume, based on the treatment gas.

The regeneration process can be carried out in batches in a closed vessel. In this batch operation, the spent catalyst and the hydrogen gas are kept in the presence or absence of hydrogen halide for the desired time at the desired temperatures and the desired pressure. The regeneration device may be a separate vessel into which the spent ^Catalyst is introduced from the reaction vessel, or it may even be the reaction vessel, which is made by a closure to form a closed vessel.

The regeneration process can be carried out in such a way that there is a stream of Passes hydrogen gas with or without hydrogen halide through the bulk of the spent catalyst. This is the preferred type for continuous regeneration.

In general, it has been observed that when hydrogen gas alone is used as the regeneration gas higher temperatures and pressures are required to recover equivalent of activity than when hydrogen halide is present. This is especially true for the Flow regeneration, whereby the hydrogen halide adsorbed on the spent catalyst shows a tendency to be completely withdrawn therefrom by the flowing treatment gas. It is preferred to work with a hydrogen gas stream containing hydrogen halide when the regeneration is carried out in a continuously flowing mode of operation.

The spent catalyst can be regenerated after removing the hydrocarbon adsorbed thereon has removed with the aid of an inert gas stream, or the catalyst can after complete Drip brought into contact with the treatment gas and the regeneration and removal can be achieved at the same time.

The regeneration process can be applied to catalysts of any particle size. The adsorbent can be in the form of extremely fine particles and, for example, of be of a talcum-like texture. The particle sizes can also extend over a range for example via a particle size

i 224 711

5 6

range, the sieve openings from about 250 to 53 mi- sium oxide-aluminum oxide. (These cocatalysts

crown corresponds. Granules or grains with size- based on alumina are for that

rem diameter, which is suitable for fixed bed processes.

nen, e.g. B. those, the sieve openings from 840 to sam, but they lead in connection with AlCl ₃

250 microns or 4760 to 2380 microns correspond to 5 a higher hydrocarbon isomerization than

can be present. The adsorbent can usually - the same amount of AlCl ₃ alone with the same process

moderate forms, e.g. B. the conditions that differ from tablets.)

Licher strength and different diameter, the designation "aluminum oxide" does not include, for example, 3.17 x 1.58 mm or 6.35 x 3.17 mm, only the Al ₂ O ₃ form, but also the aluminum or spheres of different sizes. io hydrated oxides, amorphous aluminum oxides and

In one of the known processes for the carbon aluminum oxide gels in all their known natural

Lent hydrogen conversion to be introduced fresh borrowed and synthetically produced

Aluminum chloride catalyst is known. He is made up of forms.

essentially only from an aluminum halide, the bauxite, the naturally occurring impure

which are presented on a solid, particulate adsorber 15 aluminum oxide hydrates, e.g. B. bauxite or

bens is located. A preferred aluminum halide, laterite, is also used for the cocatalyst

is aluminum trichloride. The amount of aluminum oxide based on the ad is very suitable

sorbent contained aluminum halide depends on The bauxites can, as they occur during mining,

the particular halide and the particular to be catalyzed as cocatalysts use. One can

reducing hydrocarbon conversion. 20 but also treat them to reduce their iron content

A fresh catalyst can be used to reduce any oxide, silicon oxide, or titanium dioxide,

gen of the known processes, it is advisable to lower the alkali oxide content

for example by sublimating aluminum sets.

trichloride vapors on the adsorbent material Such aluminum-containing substances, which contain considerable amounts or even large amounts of oxides due to soaking the adsorbent material as borrowed amounts or even large amounts of oxides with a solution of aluminum trichloride in one of the elements other than aluminum, can hydrocarbon until the desired amount of tri - If combined with aluminum halide, chloride is adsorbed therefrom, or by mixing, will be useful for the process. Substances, of molten aluminum trichloride with which the silicon dioxide (with the SiO ₂ as such or adsorbent. A catalyst particularly suitable for isomerizations bound to aluminum oxide and water is present is obtained by dry mixing) in addition to aluminum oxide and water of hydration, whereby solid Hold aluminum trichloride are suitable as cocatalysts on the basis and the adsorbent are mixed together by aluminum oxide, e.g. B. the synthetic and the mixture with liquid hydrocarbons in silicon oxide-aluminum oxide, which is brought into contact with carbon until the desired hydrogen cracking catalyst is used, as well as the amount of aluminum trichloride on the adsorbent, the fuller's earth.

is located. The manufacture of these catalysts is essential for a noticeable cocatalytic effectiveness

not the subject of the invention. an aluminum oxide base with a proportional

The adsorbent content of the catalyst requires a sufficiently large surface. Up to one

rose, solid substance, which is responsible for adsorption of the respective degree increases the catalytic effectiveness

ligen aluminum halide and even with the finished composition of halide and

the base to be treated in the presence of the catalyst with increasing surface area of the aluminum

Material does not react to an appreciable extent. The nium oxide base.

For the known preparation of the catalyst, the known activated ones are preferably used Usable adsorbents include: substances containing aluminum oxide hydrate (such as different types of activated carbon, ζ. B. activated plants, for example from aluminum oxides and bauxite charcoal, the various porous clays, such as fuller materials originate) as the aluminum oxide basis of the earth, aluminum-containing substances, such as synthetic catalyst used.

Silicon oxide, aluminum oxide and magnesium. The following examples are intended to illustrate this

Oxide — aluminum oxide, silicon oxide — magnesium 5 ° serve:

oxide, substances containing aluminum oxide, such as active A. A practically exclusively aluminum oxide

fourth alumina, bauxite materials such as alumina base containing active trihydrate

fourth bauxite, and the hydrated silicon oxides, were used to remove water of hydration up to

like silica gel. heated to different levels. The activity from

A preferred catalyst for hydrocarbon conversion of these various activated alumina conversion is a cocatalyst-based catalyst slowly increased in alumina as the water content increased to that of the alu-aluminum halide. The preferred aluminum halide is aluminum trichloride (AlCl ₃ ) in the form of an aluminum oxide monohydrate. Below that (15%) was reduced. In the event of further water loss, the term "cocatalyst on the basis of 60, the activity rose very quickly to a plateau-like aluminum oxide" are the most diverse aluminum maximums, which are roughly in the range of aluminum oxide substances, natural and synthetic, to oxy types with a water content as well as the various bauxite-like and Al ₂ O ₃ · 0.5 H ₂ O (8%) up to a water content aluminum-containing substances, in which aluminum oxide corresponded to Al ₂ O ₃ · 0.25 H ₂ O (4%). The mixture or in connection with silica 65 catalyst activity fell as the and / or other metal oxides are present, e.g. B. Water content further reduced to about 0.25%. Bauxite, laterite, fuller's earth, synthetic silicon was slowly decreased. Even the almost anhydrous oxide-aluminum oxide and synthetic magne-aluminum oxide with a water content of only

7 8

0.03% still produced a very effective catalyst. The composition of those in this example and

• sator. was the hexane feed used in Example 4

B. As another example, an Arkansas bauxite became like this:

with a water content of 31% (as loss on ignition.

at 1000 ⁰ C) activated and on the cocatalytic 5th Weight percent

Checked effectiveness. The catalyst activity increased 2,3-dimethylbutane 2,4

up to a plateau-like maximum in the range of 2-methylpentane 20.9

From 2 to 5 percent by weight of water. In this 3-methylpentane 29.1

The surface area of the water content was small η-hexane '36 2

ner than the maximum achievable. The maximum upper io ^ ₁₁ / wW ······ ■ ····· '

area was at a water content of more than 5 "/"> ER cyclohexane and methylcyclopentane 11.4

reaches 100.0

The lowest limit of the aluminum halide

active catalyst content fluctuates known- the isomerization was taking discontinuous borrowed with the aluminum oxide 15 used in each case carried out flow conditions. As a basis for the reaction and the halide used in each case. A metal tube with an inner diameter of 25.4 mm was used for the vessel In general, the activity increases with increasing diameter with a catalyst bed height of Aluminum halide content up to a maximum, 91.4 cm. Facilities were provided for that the aluminum oxide reaction vessel used in each case at the desired temperature basis depends. Hold a large amount of halide 20. The hexane charge was 2 to 3 geals the percentage of hydrogen chloride required to achieve maximum activity from bottom to top such can be present. In the case of aluminum - led. The feed and the reaction vessel chloride contains the catalyst generally 10 were at about 26 ° C and the bebis by weight 60 weight percent aluminum chloride. Very all-round, hourly enforced amount was at Expressed in common, the amount of aluminum is kept at 0.1. The composition of the charge trichloride showing the maximum catalyst activity and the product was determined by gas chromatography corresponds, practically the same as that determined under the. The activity of the catalyst and the acceptance the presence of a monomolecular rate of their decay was through the whole layer from flat aluminum trichloride molecules, amount of dimethylbutane in the hexane component - which on the surface of the aluminum oxide base 30 finally settles the cycloparaphytes of the product stream cling, is calculated. it's correct. In this example 8 hours of loading

The regeneration process according to the invention is passed through the catalyst bed. then If the following exemplary embodiments are used, the feed was interrupted and liquid coal illustrated. In all of these examples, the hydrogen in the reaction vessel was catalyst for 16 hours made of aluminum trichloride, which can be released. This sequence was not considered to be 1 day on a synthetic, activated aluminum counts (comparison tests between this company nium oxide or activated Arkansas bauxite with discontinuous flow and real found. In all cases, the fresh catalyst was showing continuous flow through that prepared in such a way that a dry mixture of this procedure, accurate and adequate comparisons of aluminum trichloride and the adsorbent values of the catalysts are obtained), det and this dry mixture then with On the 2nd day contained the runoff from an experiment 1. a stream of a natural hexane mixture using fresh catalyst 65 »/ 0 DMB

with a content of about 10 mol percent ί? ™ ⁶ ^! ^: ψ ^Ο \ 11 ¹ ^ ™? ν * «" ?

Cyclohexane and methylcyclopentane or DMB content dropped to 38 <> / "at around 26 ° C

9 ν. _t 45 this time the temperature was down to 40.5 ºC

. n- u an increased, resulting in an increase in conversion to

- depending on the isomerization with the catalyst led to about 50%. The attempt was up to

rende hydrocarbon - approximately at the isomer 33rd day continued, where the DMB content to 40 ° / »

temperature was brought into contact. had fallen.

The fresh catalyst was then used to isomeric. The reaction vessel was emptied and the liquidation of the respective hydrocarbon charge with nitrogen from the spent catalyst of the liquid phase was used until the activity was removed. The catalyst had reached a certain point from the pure state, which was removed through the action vessel and placed in an autoclave with a content of dimethylbutanes or isobutane. The autoclave was designed with bottled water drainage. 55 fabric brought to a pressure of 35 atmospheres and on _B. -I ₁ heated to about 149 ° C, after which the pressure was 49 atmospheres _{. The temperature of} 1490 _c wuj-de 20 hours

The fresh catalyst contained 80 weight sustains. After that, the treated

percent activated aluminum oxide from a sieve catalyst into the

60 mung operated reaction vessel corresponding to openings of 840 to 250 microns are returned and

Particle size and 20 percent by weight of a tech- the operation under the same conditions as them

niche variety of aluminum trichloride. That were actively applied for the fresh catalyst, as-

fourth alumina exhibited one absorbed by nitrogen. The initial transformation lay

absorption specific surface of about 300m ² / g at 57 ° / »DMB in the product. The activity decreased

on. This aluminum oxide was 16 hours at 65 and by the end of the 9th day the DMB level was

Dried about 454 to 510 ° C and then cooled, holds 45%.

before it is used to manufacture the catalyst. At this point, the spent catalyst was

became. lysator in the reaction vessel itself treated.- The

9 10

The hydrocarbon has been removed from the catalyst. The isomerization was carried out at a temperature The reaction vessel was sealed and heated to about 35 ° C, a pressure of about 14.7 atü, Bottled hydrogen to a pressure of 35 atmospheres for an hourly weight-related breakthrough. Then it was set at a temperature of 0.1 and a throughput temperature for 20 hours of 149 ° C and a pressure of 49 atmospheres - a speed of about 725 g / hour is carried out, obtain. Thereafter, the hydrogen was vented before the hexanes used as feed into the and the feed was introduced under the conditions of the reaction vessel, they were passed through Turning fresh catalyst into the reaction vessel, the aluminum trichloride as a saturation vessel introduced. The initial conversion contained modifying agents. About 4 percent by weight of the carried 57% DMB in the product. On the 9th day the Ak- io feed of HCl were compared with the feed as Activity dropped to 47%, whereupon the experiment was introduced promoter for the catalyst. In the ended. For the 8th hour, the outflow of product contained 60% di-The above example illustrates the remethylbutanes. The attempt was continued for 170 hours of used catalyst set at one, after which the effluent is 55% DMB Procedure without the use of chlorinated water-15 contained.

material. It can be seen that regenerated catalyst was The spent catalyst was produced by a stream of hydrogen gas having essentially the same activity, 0.125 m ^{3 of} hydrogen per K as a fresh catalyst by treating grams of catalyst and hour, which produced 10 percent by volume of hydrogen under these conditions , based on hydrogen, in chlorine water. The regeneration of a similar catalyst used for isomeric 127 ° C and a pressure of 29.75 atmospheres for 24 hours of η-butane was passed through the catalyst bed, regenerated, regenerated, regenerated, also showed very favorable results. The regenerated catalyst was then among the

the same conditions as for the fresh cat

Example ^{2 a5} tysator applied, reinserted. In the

9th hour contained the hexanes formed 59%

It was the regeneration of a DMB catalyst. The experiment was continued for 120 hours,

investigated, the isomerization of the natural, according to which the DMB content of the hexane product is 53%

borrowed mixture of hexanes in a large fixed-amount.

bed system accrued. The reaction section was 487 cm 3 <> At about 127 ° C was for 24 hours at

high and had an inside diameter of about 29.75 atm a second regeneration with hydrogen

50 mm. The reaction vessel was run with heating equipment and 10% hydrogen chloride supplied by

gene provided to temperatures within a white passed up through the catalyst bed

th area including a temperature gradient. The regenerated catalyst obtained in this way

upright along the height of the reaction vessel led to the formation of 59% DMB at the beginning

to be able to receive. and after 63 hours the DMB content was 58%.

A third regeneration with 1% HCl was used to prepare the fresh catalyst

carried out the hydrogen containing aluminum oxide described in Example 1, the above

turns. It was washed by passing 3 liters of a 5ge downwards. Treatment was

weight percent aqueous hydrochloric acid per kilogram 40 36 hours at about 163 ° C and 29.75 atm

Aluminum oxide and then distilled water. After starting up the catalytic converter

water was passed through a bed of aluminum oxide - after this third regeneration the initial

the. Then 4 hours at about 15O ⁰ C and Liehe DMB content in the product 53%, and after

Dried 16 hours at about 454 to 510 ° C. The DMB content was 48% for 111 hours.

This treatment resulted in the original 45. A fourth regeneration was carried out using

Surface area of 306 m ² / g not significantly changed. of hydrogen containing 1% HC1.

80 parts by weight of this activated aluminum oxide out. The treatment was carried out at a temperature

with a sieve opening of 840 to 250 micron temperature of about 232 ° C for 12 hours

speaking particle size and 20 parts by weight 29.75 atm. During this fourth regeneration

of a powdery technical aluminum trichloro-containing catalyst led to the formation of 60%

rids were mixed together and added to the DMB at the beginning and from 50% DMB after 135 hours

Reaction vessel introduced. The catalyst was running out of time.

on the spot by introducing the as loading It was a total of eight times under similar loading serving hexanes in the ordinary conditions and regenerated with similar results. Isomerization temperature of about 35 ° C. After the eighth and final regeneration represents. 111 hours of operation, DMB formation was 57%

The hexane charge had dropped to 43% as follows.

setting: The above example shows that with a half-

Weight percent technical working method regenerated eight times

_ _ ^. , “60 Catalyst is practically as effective as the

2,3-dimethylbutane 2,4 fresh catalyst.

2-methylpentane 21.7

3-methylpentane 29.0 Example 3

n-Hexane 36 3 This example serves to illustrate the

Methylcyclopentane 2 6 ^6s regeneration of a catalyst, for the activated one

_. . 'Arkansas bauxite is used as an adsorbent. Of the

(Jycloüexan 8.0 bauxite was washed with hydrochloric acid and approx

100.0 calcined at 482 ° C for 14 hours. The catalyst

was obtained by dry blending of 30% aluminum trichloride with bauxite having a sieve aperture of 840 to 250 microns · particle size prepares. The reaction vessel, charge and procedure were as described in Example 1. The isomerization was carried out at 26-27 ° C. Six regenerations were made. All regenerations were batchwise in the reaction vessel itself at one temperature of 149 ° C using bomb hydrogen under a pressure of 49 atü. No attempt was made at any particular conversion for a given DMB level cancel each work step. The operating time in days and the number of regenerations are shown in the following table.

Table 1

Operating time DMB at the end catalyst in in the hexane product 38.9 Days at the start 53.8 Fresh catalyst 4th 56.3 40.0 1. Regeneration 10 62.7 38.6 2. Regeneration 9 62.3 42.3 3. Regeneration 11 62.7 42.0 4. Regeneration 9 61.3 - 5. Regeneration 10 60.9 6. Regeneration 2 62.8

The above example shows that bauxite can be used as an adsorbent for static regeneration without additives of HCl is particularly accessible under moderate treatment conditions.

It has also been found that fresh aluminum supported catalysts are activated when these fresh catalysts, either a preformed one Catalyst or a dry batch catalyst precursor with hydrogen gases in the same, are treated in the manner described above.

The treatment is continued until a catalyst with improved activity is obtained. The lower limit of the treatment time depends on the particular halide and the particular adsorbent and the other conditions of the treatment with the gaseous hydrogen.

As a rule, particularly good results are achieved if the treatment is carried out at a temperature between 121 and 205 ° C. and a partial hydrogen pressure of about 21 to 56 kg / cm ² . A significant increase in catalyst activity is achieved under these conditions in about 4 hours, but longer periods of time, which can be 72 hours or more, are often used. There is a point at which significant activity improvement is no longer achieved even with extreme treatment times.

The treatment with the gaseous hydrogen can be carried out in batches, the Hydrogen is pressed into a closed vessel, the fresh, preformed catalyst or the dry mixture contains. However, the hydrogen treatment can also be carried out continuously the gas flow through the bed of particles of the solid, fresh, preformed catalyst or passed through the bed of the dry mixture. When using the continuous, flowing operation, the hydrogen stream preferably contains some hydrogen halide.

The hexane feed used in the following experiments was from a catalytic one Reforming. From this reformed product were aromatic hydrocarbons and olefins practically completely removed. Except the

ίο Hexanes contained the charge, about a total of 10 percent by volume methylcyclopentane and cyclohexane. The loading was through a bed of Catalyst particles passed, which in a reaction vessel of 25.4 mm inner diameter a height of Occupied 91.4 cm. The liquid feed contained about 4 weight percent hydrogen chloride as a promoter, the isomerization was carried out at a temperature of about 26 to 27 ° C, and the Weight-related hourly throughput speed

ao speed was 0.1. The feed and product were analyzed by gas chromatography. In all tests there was no noticeable loss due to the formation of pentanes or lower hydrocarbons or of heptanes or higher hydrocarbons. The activity of the catalyst was performed at each attempt by the di- ^v methylbutane content of the Hexananteils in the effluent product tracked.

Example 4 30

Four runs were made with a catalyst made from an engineering grade aluminum trichloride and arcansas bauxite with a sieve aperture of 840 to 250 microns particle size. Before being used to produce the catalyst, the bauxite was calcined at 480 ° C. for about 12 hours. In all runs the catalyst was prepared using the same procedure, with the liquid feed being introduced into the dry batch in the reaction vessel and the catalyst formed in this manner at the start of the run. For this reason, the dimethylbutane contents are given for each test from the 2nd day of the continuously flowing mode of operation. The hexane product, the DMB content of which is given, does not contain any cycloparaffins. In all experiments the catalyst consisted of 80% bauxite and 20% AlCl ₃ . The isomerization was carried out at 26 to 27 ⁰ C, and the liquid feed contained HCl.

Attempt 1

A typical control catalyst was prepared. The bauxite was washed with hydrochloric acid and water to remove the acid, dried overnight in an oven at 121 ° C (250 ° F) to remove the water, and then calcined. A dry mixture of the bauxite and the AlCl ₃ was introduced into the reaction vessel. then

the attempt was started.

Attempt 2

A dry mixture was prepared from acid-washed, calcined bauxite and AlCl _3. The dry mixture was subjected to static treatment with hydrogen in the reaction vessel. Bomb hydrogen was. Injected to a pressure of 35 atü at room temperature.

10

The reaction vessel was then held at 149 ° C. and 49 atmospheres for 20 hours. The gas was out of the Reaction vessel drained and liquid charge introduced.

Attempt 3

The catalyst production corresponded to that in the experiment 2 except that the bauxite was not acid washed.

Attempt 4

The acid washed, calcined bauxite was placed in an autoclave. Hydrogen was injected into the autoclave and the contents of the autoclave were kept at 149 ° C. and 49 atmospheres for 20 hours. Then the hydrotreated bauxite was _{mixed with AlCl 3} into a dry mixture which was introduced into the reactor. Liquid feed was then introduced and the experiment started. so

The dimethylbutane contents of the hexane product from these four runs are given in the following table. Each trial was continued for a total of 16 days. After that, the mean DMB content calculated. The table shows the DMB levels for each experiment on certain Days specified.

Table 2

Dimethylbutane content in the hexane product Attempt no. 3 4th After days 2 63.5 56.8 1 64.5 63.5 49.6 2 58.2 64.4 60.5 45.5 3 51.3 62.4 57.1 45.9 6th 45.4 57.8 53.7 43.4 8th 44.5 55.5 - 43.2 10 43.6 52.3 45.0 - 12th 42.7 47.2 43.0 43.4 14th 41.1 . 46.5 16 39.9 55.8 46.0 Average 56.3 (16 days) 44.7

pretreated catalyst, d. H. the catalysts of experiments 2 and 3. The catalysts of experiments 1 and 4 results appear to be within the margin of error found when repeating Tests of this kind must be accepted.

Example 5

30th

35

The above data show that with the hydrogen-pretreated catalysts of experiments 2 and 3, much higher amounts of dimethylbutane are formed on day 2 than with the control catalyst of experiment 1. Experiment 4 shows that between the control catalyst and its production no hydrogen was used and the catalyst, with the bauxite alone having been subjected to the hydrogen treatment before the catalyst was prepared, there is no substantial difference. Over time, the DMB product for experiments 2 and 3 remained at higher values than for experiment 1. The activity of the acid-washed bauxite of experiment 2 seemed to be retained to a somewhat better extent than that of the catalyst of experiment 3. The mean DMB Formation for the entire 16 days gives a very surprising benefit to the hydrogen _{preformed catalyst containing 20 weight percent AlCl 3} and 80 weight percent synthetic activated alumina was used in comparative tests performed as described above.

Attempt 1

A typical catalyst was made by treating a mixture of AlCl ₃ and alumina with boiling cyclohexane. The finished catalyst was then introduced into the flow-through reactor, and the experiment was carried out for 25 days at 4.4 ° C. with the hexane mixture from Example 4. On the 4th day the DMB production was 37%. The DMB content increased gradually and was about 40% after 25 days. Then the experiment was ended.

Attempt 2

In this experiment, the pre-formed catalyst was introduced into the reaction vessel and one subjected to static treatment with bomb hydrogen at about 49 atm and 149 ° C for 20 hours. Of the DMB content of the product obtained in this experiment at 4.4 ° C. was 62% at the beginning. This Activity level was fairly accurately maintained for about 20 days. Then the experiment was ended.

Claims (3)

Patent claims: 1. A process for activating fresh and used for the regeneration of catalysts consisting essentially only of aluminum halide on a solid adsorbent, characterized in that the fresh or the catalyst used in a hydrocarbon conversion process is mixed with hydrogen-containing gases at 65 to 316 ° C treated under a hydrogen partial pressure of at least 7 kg / cm ² until its activity for the respective hydrocarbon conversion has risen considerably above the initial value. 2. The method according to claim 1, characterized in that hydrogen gases are used, which contain a hydrogen halide which corresponds to the halogen present in the catalyst. 3. The method according to claim 1 and 2, characterized in that one also with the Hydrotreated catalyst in contact with a liquid saturated hydrocarbon who, under the conditions used, has an adequate solving power for the Has aluminum halide. 609 660/409 9.66 © Bundesdruckerei Berlin