DE1200264B - Process for the production of a carrier suitable for hydroforming catalysts - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

BOIj

German class: 12 g - / ·

Number: 1 200 264

File number: E16835IV a / 12 g

Filing date: December 6, 1958

Opening day: September 9, 1965

The latest developments in the petroleum refining industry have focused on processes for converting low-boiling hydrocarbons especially those in the middle and upper part of the boiling range of raw gasoline, in products with improved Concentrated octane number. The so-called hydroforming process has been very successful in this direction achieved.

In this hydroforming process with pressures from 3.5 to 70 kg / cm ^2, preferably 7-49 kg / cm ² and at temperatures of 370-593 ⁰ C, worked up to 51O ⁰ C, preferably 468th The hydrogen dilution can vary between about 17 and 34 m ³ / hl.

A particularly suitable catalyst for this process turned out to be platinum on alumina as a carrier, which was preferably made from aluminum alcoholate. One of the most widely used catalyst mixtures this type contains about 0.001 to 2.0 weight percent platinum, the remainder consists of the clay as a carrier.

A particularly suitable form of alumina as a carrier, namely γ-alumina, has hitherto been found produced by the following process: aluminum metal is set with a water-insoluble anhydrous Alcohol, hydrolyzes the aluminum alcoholate obtained, separates the aqueous alumina from it Alcohol and wins the clay from its aqueous suspension. The adsorbent clay thus obtained however only contains about 30% ?? - clay, the rest consists of the y-form. It has been shown that The higher the? / - alumina content, the better the performance of the catalyst and its durability in the carrier and the larger the pore diameter of the alumina particles.

The selectivity in the treatment of the hydrocarbons does not change.

Aluminas containing at least 80 weight percent-alumina ^, is obtained by hydrolysis of AIuminiumalkoholatlösungen in hydrocarbons in the presence of dilute aqueous ammonia at temperatures from 1.7 to 37 ⁰ C.

The hydrolysis of an aluminum alcoholate with 10 percent by volume of concentrated ammonia at 26 to 37 ° C for the production of / 3-alumina trihydrate is known. However, this gives catalysts which are far less effective compared to the coarse-pored catalysts prepared according to the invention.

According to an older shack, a hydroforming catalyst with a high content of i7-alumina is produced by adding the alcoholate with 1 to 10 parts by volume of an ammonium hydroxide solution containing 1.8 to 3.4 percent by weight of ammonia, a process for producing a
Hydroforming catalysts suitable
Carrier

Applicant:

Esso Research and Engineering Company,

Elizabeth, N. J. (V. St. A.)

Representative:

Dr. W. Beil and A. Hoeppener, lawyers,

Frankfurt / M.-Höchst, Adelonstr. 58

Named as inventor:

Isidor Kirshenbaum, Westfield, N. J .;

John A. Hinlicky, Irvington, N. J. (V. St. A.)

Claimed priority:
V. St. v. America 9 December 1957
(701 462)

hydrolyzed at 1 to 38 ° C, the aging time V is ₂ to 15 hours, and the annealing temperature is between 200 and 68O ⁰ C.

It has now been found that a catalyst support suitable for hydroforming catalysts with a high content of ^ alumina, ie of at least 80 percent by weight, and a coarse-pored structure by hydrolysis of aluminum alcoholates with 1 to 10 parts by volume, based on the amount of alcoholate, a 1, 8- characterized receives up 3,4gewichtsprozentigen ammonia solution, aging the resulting alumina hydrate Lamb, filtration and annealing, that the hydrolysis is carried out at a temperature of 38 to 8O ⁰ C.

It is true that a similar process has already been proposed for the production of a catalyst support with a high content of alumina by hydrolysis of aluminum alcoholate and calcination of the alumina hydrate obtained. Here, however, the hydrolysis temperature at use is to be a 10% ammonia solution for the hydrolysis lower (26 to 37 ° C) to 815 ⁰ C and the annealing time be 2 to 16 hours, the annealing temperature is 590, and in particular the clay must after annealing be deterred. According to another older, but also not previously published proposal, the hydrolysis temperature should

509 660/470

3 4

rature between 1 and 38 ⁰ C, the aging period NH ₄ OH per volume of alcoholate, preferably 2 to

V be ₂ to 15 hours and the annealing temperature 3 parts by volume per volume of alcoholate solution, hydrolyzate

between 200 and 680 ° C. sated. The NH ₃ concentration in the hydrolysis

The medium is preferably about 1.8 to 3.4 percentages.

those according to the present invention by the above 5 percent by weight. Higher concentrations of ammonia in

named range of the hydrolysis temperature. Only the hydrolyzing medium tend to be the larger

by the special selection of this working condition pores in the formed adsorptive clay to

it is possible to eliminate the content of the catalyst support. The hydrolysis temperature is between

»/ -To keep clay particularly high and at the same time 38 and 80 ° C; the most favorable is a temperature

the carrier has a very high content of macropores ίο between 57 and 80 ° C. At temperatures in the lower

to lend, through which the finished catalysts are part of the range mentioned lower ammo

particularly effective and long-lasting, niak concentrations are preferred. The crystalline

whereby the new type of carrier above all known aqueous alumina suspension is left in the aqueous one

similar alumina carriers are advantageous. Medium at least about 1 hour up to 120 hours

It is beneficial to age the total amount of used 15. The higher the hydrolysis temperature, the longer water, the time during which the aqueous clay is generally the required aging time. When held in the aqueous slurry before this aging is usually kept temperatures this is dehydrated to the aqueous clay between 1.7 and 26 ° C, z. B. convert 12 to 23 ° C, and in vorzugsvorwiegend / J-alumina trihydrate, SO, 10 a to 18 ⁰ C. According to a preferred way of regulating the stirring speed of the hydrolysis mixture, a solution of Alu is hydrolyzed. By appropriate control of this miniumamylat in such a way that it slowly factors can be an alumina with the desired and with thorough stirring at about 79 ⁰ C to a pore properties and the aforementioned ^ -content dilute ammonium hydroxide solution (3.0 weight. - Alumina can then be used with a different percentage of NH ₃ ). The aqueous alumina catalyst constituents obtained are mixed in a known manner and allowed to become suspension at about 15 ^° C. for 72 to 96 hours. age with the formation of large crystal aggregates which

The maintenance of the hydrolysis temperature is for the subsequently dewatered, dried and 4 hours

Achieving an adsorptive alumina measured at 593 ⁰ C to be annealed. The usage of

allegedly, in which a large part of the pores have a through-NH ₄ OH is particularly advantageous where the alcoholate

has a diameter of more than about 100 Å, and more than 30 is slowly added to the water. In this case

40% of the total pore volume is coarse pores, i.e. H. a shorter aging time is required, calculated

those with diameters of 0.05 to 1 μ include. from adding the last drop of base.

The aluminum used as starting material is assumed to be water-insoluble if alcoholates are used alcoholates are usually obtained by converting alcohols, which is then formed in the hydrolysis stage Settlement of metallic aluminum with practically 35 resulting alcohol, together with that as water-free Alcohol in the presence of such cata- thinning agents used hydrocarbons, a lysers, such as mercury salts, iodine or aluminum layer, produced by the suspension of the hydrous halides. Suitable alcohols are ethyl, propyl, aluminum oxide which is clearly separated and easily Isopropyl, n-butyl alcohol, secondary butyl alcohol, win and od by simply decanting. Like. Isobutyl alcohol, 1-pentanol, 2-pentanol, 3-methyl-40 can be separated off.

1-butanol, 2-methylbutanol-3, pentanol-3, hexanol-1, but if you are from an alcoholate of a water-

Hexanol-2, Hexanol-3, the various methyl-soluble alcohols started, so goes back

pentanols and dimethylbutanols, the various alcohols formed after hydrolysis of the alcoholates in

Heptyl alcohols, octyl alcohols, etc., as well as those in water in solution and can be extracted from it

higher alcohols, which are obtained at the process temperature 45 distillation. The alcohol must then

are liquid. Instead of using the alcohols individually, dehydrated in a known manner to the anhydrous form

you can also use mixed alcohols, e.g. B. mixed can be dratized before going back with more

Amyl alcohols, take. Mixtures of alcohols are converted to metallic aluminum,

of different molecular weights are also. After aging it is preferable to dry first

useful. 50 the clay suspension in which most of the clay

In general, water is preferably not earth in the /? - trihydrate form and in which the miscible alcohols, ie alcohols with 5 or more alumina hydrate crystals, have sufficiently large aggregates of carbon atoms, since this has formed the recovery of the alcohol or tufts, e.g. B. at 93 to 204 ⁰ C or in anhydrous form for reuse for above, to remove the ammonia and the aqueous medium, the production of further aluminum alcoholate in which it is contained, and to lighten the clay. To be obtained in the production of the aluminum alcoholate. The crystalline vj-alumina is then obtained by mixing a hydrocarbon with the alcohol by further dehydrating the / 3-alumina, which hydrates the boiling range of the alcohol used (bayerite). This has been found to include e.g. For example, a petroleum distillate is virtually quantitatively with a conversion if the Akti-boiling range of 93 to 26O ⁰ C or above, preferential 60 vierungstemperatur 205-760 ⁰ C, with a narrow boiling range vorweise. Instead of preferably about 593 ⁰ C is. To activate the glowing hydrocarbon fraction, the alumina can generally be added in the presence of selected hydrocarbons, such as heptane, octane, toluene, air, or else in vacuo or in the presence of other xylene, and so on. The addition of the hydrocarbon inert gases. Because the aforementioned conversion of the substance is important for the practical success of the process 65/5 trihydrate in ij-alumina, this treatment can be important. also serve to set the amount of ^ -phase in the tone-

The aluminum alcoholate is used under good soil to determine which is the activation of the

Stir with about 1 to 10 parts by volume of aqueous hydrolysis product.

This annealing or activation treatment can also be applied to the addition of the active catalyst component follow to the support, keeping the combined catalyst at the same temperatures glows. Similarly, one can use the dehydrogenating agent or the active catalyst ingredient add to the carrier either before or after it has dried. The effective catalyst component can z. B., as known, from molybdenum oxide, vanadium oxide, tungsten oxide or chromium oxide or from metal salts molybdic acid, such as calcium molybdate or cobalt molybdate, or preferably from precious metals, such as platinum or palladium, with which together the carrier a good hydroforming catalyst results. The catalytically active component can be incorporated in any known manner, z. B. slurried with the hydrous clay, or by impregnation or sublimation. at Impregnation with ammonium salts, e.g. B. with ammonium molybdate, however, it is necessary that the / 3-trihydrate or the »/ -form of the clay already before the addition of the ammonium molybdate is formed.

The invention will now be explained in more detail with reference to the following examples, the various production methods the catalyst support, the properties of these supports and the effectiveness of those made with them show finished catalysts.

example 1

An aluminum amylate solution was prepared by dissolving 432 g of aluminum shavings in 161 of a mixture of equal parts of anhydrous n-amyl alcohol and a ^{petroleum distillate boiling between 148 and 205 0} C using a small amount of mercury chloride (about 0.0005 parts by weight per part by weight of aluminum) as a solution catalyst for the metal was produced, the mixture being brought to the boil by means of a steam coil to start the reaction. After the reaction got off to a good start, cooling was required. Towards the end of the reaction, the mixture was heated again until the metal had completely dissolved.

Some samples of the aluminum amylate solution thus obtained were at various temperatures under Use equal amounts of space of water or aqueous ammonia, as indicated, hydrolyzed. The aging time was also changed to determine the influence of these variables. Below the results:

Influence of NH ₄ OH and the temperature and the aging time on the hydrolysis of the aluminum amylate

hydrolysis NH ₃ concentration Aging Weight percent
/! - trihydrate temperature tration UCt L ^ i KJL lllcll "
temperature in the at 121 ⁰ C
dried ⁰ C ° / o hours Clay 26th no 40 78 2.4 0.5 90 2.4 4th 100 57 2.7 40 100 57 2.7 2 70 65 no 40 28 2.4 0.5 *) 70 2.7 40 65

These results show that the higher the hydrolysis temperature, the longer the aging time required. They also show the marked improvement achieved through the use of aqueous solutions of ammonium hydroxide as a hydrolysis agent. Thus, for example received in a V2 ^st ündigen aging with 2.4% ammonia at 26 ° C better results than a 40stündigen aging in the absence of NH ₄ OH. The numbers also show how

ίο a 100% »/ - alumina _{can be obtained in less than 4 hours using NH 4} OH, compared to an aging time of 40 hours required to achieve the same» / - alumina concentration in the absence of NH ₄ OH . The ^ trihydrate is converted by 4stündiges annealing at 593 ⁰ C in "/-alumina.

As already stated, the conversion of / S-trihydrate to the »/ -form is quantitative, and the given numbers refer to the »z-alumina content close the hydrolyzate.

Example 2

Catalysts were prepared which consisted of 0.5 weight percent platinum on various types of alumina passed, the latter containing various amounts of »/ clay (remainder in the y-form). These Catalysts were used for the hydroforming of an untreated raw gasoline charge (Coastal, octane number 50) with a boiling range of 93 to 165 ° C. The hydroforming process was carried out under the following Conditions carried out:

Pressure 14 kg / cm ² , temperature 482 ^° C., hydrogen / hydrocarbon ratio 6; 1, throughput = 4 w / h / w.

As a result, it was found that the with »/ clay produced catalyst has an efficiency expressed by the octane number 100+, while y-alumina is used as the carrier, a catalyst is obtained, but only one is obtained when using it Reached an octane rating of 94.5. The investigated catalysts were subjected to an accelerated aging test subjected by heating them in air at 675 ° C for 64 hours. This treatment includes much stricter conditions than those encountered in a year of regenerative work. From this it can be seen that »/ -Alumina catalysts are clearly superior to y-alumina catalysts (octane number 98 compared to an octane number of 89). It has also been shown that with a heat aging The performance of the catalysts produced with / - alumina goes down only by 2 octane units, while the performance of the catalysts made with γ-alumina drops by about 6 octane units.

Example 3

*) After rapid cooling (less than
Normal temperature.

Hour)

2.8 l of concentrated ammonium hydroxide solution were added to 28 l of distilled water at 65 ° C., resulting in a solution with 2.8% NH _{3 content.} To this solution, 41 aluminum amylate solution was added slowly and with vigorous stirring. After the addition was complete, the hydrolyzate was stirred for a further 1 hour, then the sample was placed in a large flask and allowed to age for 40 hours at room temperature, the pH being 10.5. The Abfangstemperatur the ammonium hydroxide solution was 74 ° C and the final temperature of the hydrolyzate of 62 ° C. The clay was separated, Ge 16 hours at 121 ⁰ C.

dries and then calcined ^{at 593 0 C for 4 hours.} This sample is referred to as Sample E hereinafter.

157.8 ecm of a solution of 3.95 g of chloroplatinic acid in distilled were added to 263 g of the alumina obtained Given water. The impregnated powder was mixed thoroughly and only left for 16 hours Room temperature and then dry for 16 hours at 120 ° C, whereupon beads are formed from it and finally burned for 1 hour at 593 ° C.

Another sample of alumina (Sample F) was hydrolyzed in water at the same temperature as sample E, and two other samples (G and H) were made with the same concentrations of ammonium hydroxide manufactured at different temperatures and aging times. The different clays were each separated, dried and under the same conditions as in the preparation of the Sample E annealed. The individual samples were then processed into a platinum catalyst from same platinum content as sample E and in the same way as this. The different catalyst samples were then tested under normal conditions in an isothermal system. The data of the various clay samples as well as the The activity of the catalysts produced therefrom can be seen in the table below.

Clay
sample hydrolysis
medium Hydrolysis-
temperature
⁰ C Aging time
in hours
(a) jS trihydrate
% Relative
effectiveness
of the catalyst
(b) Total pore
volume
ccm / g Pore volume
in macro
pores (c)
° / o E.
F.
G
H 2.8% NH ₃
water
2.8% NH ₃
2.8% NH ₃ 65
65
26th
57 40
40
40
2 65
30th
100
70 150
70
100
90 0.785
0.415
0.755
0.700 60
20th
50
46

(a) Without aging temperature control; Start at hydrolysis temperature and cool to room temperature.

(b) 0 ₅ 6 ° / "platinum on 4.7 χ 6.3 mm Kügelehen; 0.6% Cl; 16 W / h / W at 482 ° C.

(c) pores with a diameter of 0.05 to 1 micron.

From the table above it can be seen that a catalyst of exceptional effectiveness is obtained with that alumina (sample E) as a carrier obtained by hydrolysis at high temperatures in dilute ammonia followed by prolonged aging at room temperature. It appears that the high hydrolysis temperatures and vigorous agitation are responsible for the formation favor smaller crystallites, while the longer aging period at normal temperature a slow one Crystal growth allows, which leads to larger aggregates, which in turn have a particularly large development of macropores.

A clear difference can be seen when comparing sample E with sample G in the table above, insofar as than the former, the effectiveness is 50% higher, although the content of ?? - alumina (previously used as the main criterion for catalyst performance was) was considerably lower. The additional meaning contributes to aging at low temperatures following hydrolysis with dilute ammonia A comparison of samples E and H at high temperatures shows 60% of the relative effectiveness are lost when the aging time is reduced from 40 to 2 hours. This last circumstance stands also related to the aging temperature, since the hydrolyzate during the short Aging time of 2 hours cooled from the initial temperature of about 57 ° C and thus one had a significantly higher average temperature than the alumina that had been aged for 40 hours.

Results similar to those obtained with the platinum-containing catalysts described above are also obtained when the catalyst supports according to the invention contain other catalytically active substances.

The catalysts according to the invention are suitable for hydroforming, hydrogenation, hydrocracking, Cracking, oxidation and other known reactions of this type. The catalysts are particularly suitable for the production of aromatic compounds from naphthenes and for cyclization dehydrogenation of paraffins and olefins.

The individual names of the crystal modifications of alumina and alumina hydrates that are now are common in the literature and were also used here, are in detail in an article by H. C. Stumpf et al. the Aluminum Company of America in "Industrial and Engineering Chemistry", Vol. 42, p. 1938 (July 1950).

The catalyst supports produced by the present process can be either in powder form as well as apply as pills, extruded bodies, etc. Ammonia is the preferred hydrolysis agent, however, under certain circumstances, organic bases such as amines, piperidine and hydrazines can also be used take advantage of it.

Claims (2)

Patent claims: 1, Method of producing one for hydroforming catalysts suitable carrier with a high content of jj-alumina by hydrolysis of Aluminum alcoholates with 1 to 10 parts by volume of a 1.8 to 3.4 weight percent ammonia solution, Aging of the resulting alumina hydrate sludge, filtration and annealing, thereby characterized in that the hydrolysis is carried out at a temperature of 38 to 80 ° C will. 2. The method according to claim 1, characterized in that the hydrolysis is ^{carried out at 57 to 8O 0} C and the alumina hydrate is aged for 1 to 5 days at temperatures between 12 and 23 ° C. Considered publications:
German interpretative document No. 1 014 689. Legacy Patents Considered:
German Patent No. 1 042 801. 509 660/470 8.65 © Bundesdruckerei Berlin