DE957588C - Process for the preparation of a hydrocarbon conversion catalyst - Google Patents

Description

ISSUED FEBRUARY 7, 1957

St 5716 IVc 123b

The present invention relates to the preparation of catalysts for conversion and Treatment of hydrocarbons. In particular, it relates to the production of improved catalysts, the relatively small amounts of a precious metal, such as. B. platinum or palladium, on one contain suitable catalyst support applied and for hydroforming of hydrocarbons are suitable.

The use of noble metal catalysts, especially those containing platinum and palladium, provides many known advantages in the treatment and conversion of hydrocarbons and hydrocarbon derivatives. The effectiveness of such catalysts is in many ways related to the very strong affinity of these metals for hydrogen in connection. They can be used in many known ways to remove hydrogen from organic

niche compounds are used, which in some cases is a simple dehydration and in in other cases aromatization, ring formation or reactions result from the hydrocarbons are coupled together.

It has also been found that in many cases the type of hydrocarbon reaction that occurs in the presence of a platinum or another metal from the VIII. Group of the periodic table containing catalyst ίο takes place, significantly influenced by the nature of the carrier carrying the active metal will.

A particularly useful combined or synergistic effect of this type has been found with platinum or Observed palladium catalysts which are applied to an alumina support. The exact The type of catalytic conversion effected by these catalysts depends to a considerable extent Dimensions depend on the nature of the clay base.

According to the present invention, catalysts for converting hydrocarbons with ο, οΐ to about ι percent by weight of a noble metal, for example o, i to ι ° / ₀ platinum, and an alumina carrier mixture are prepared in such a way that you first create an intermediate concentrate by applying a compound of the noble metal on a solid oxidic carrier by soaking it with a water-soluble compound of the noble metal in such an amount that the concentrate contains up to 35 percent by weight of the noble metal, based on the total weight of this metal and the carrier, whereupon the concentrate is dried and then diluted with a predominant amount of finely divided, predried clay or substances or mixtures containing clay in such an amount that the finished mixture has the total content specified above. Has precious metal. The carrier used for the intermediate concentrate can be an oxide of aluminum, silicon, magnesium, titanium, zirconium, thorium and / or zinc. The alumina-containing additives used for dilution should preferably be adsorptive and ideally consist of active alumina. These adsorbents can also themselves have their own catalytic effect enhanced by smaller amounts of solid oxides, namely those of silicon, chromium, magnesium, titanium, zirconium, thorium, boron and / or zinc.

Of the combinations possible below, those that are most significant for practice are at which also the catalyst carrier of the intermediate concentrate is alumina and the noble metal Consists of platinum or palladium.

Active clay which is suitable for part or all of the carrier for the invention Catalysts produced can be used are known per se in the relevant art and readily available commercially. Two activated alumina and one α-alumina or corundum, the have been investigated in the preparation of these catalysts are identified in more detail below.

Table I.

Activated clay

Surface area, m ² / g
Pore size, in

Ä units
Porosity, in%.
Approximate chemical

Analysis, in
Weight percent

Al ₂ O ₃

SiO

Na ₂ O
Fe ₂ O ₃

Loss when heated to 510 ° ...

F-io

40
35

96.0
0.1
0.1
0.05

3.0

200 to 300 0.3 to 0.1

30th
50

90.0

5.5
0.1
0.12

8.5

T-75

-

16 to 20

99.5
0.02

0.05

It goes without saying that the activated clays "H-4iff" and "F-io"? just examples of such clays and that other commercially available active clays can also be used.

The activated clay can be used as received, or it is preferably predried at temperatures from 93 to 120 ^° for about 2 to 24 hours. The predried clay is then mixed with a solution of a suitable platinum or palladium salt, such as. B. chloroplatinic acid or palladium chloride, mixed. The concentration of the impregnating solution and the amount used thereof can be chosen so that a relatively thick paste is formed when this solution is mixed with the activated alumina, or the platinum or palladium can be adsorbed onto the alumina from very dilute solutions. The amount of chloroplatinic acid or palladium chloride to be added varies somewhat depending on the activity desired for the finished catalyst.

In this way you can make any concentrates with a higher precious metal content than the finished product Preparation or even the precious metal salt in dry undiluted form immediately add to the total amount of the vehicle. However, it has been found that the use of the Intermediate concentrate is preferable, especially because e.g. B. chloroplatinic acid, d. H. the on Easiest available form of platinum that is hygroscopic. The production of the intermediate concentrate facilitates the physical handling of this material and its distribution in the carrier. the highest concentration, which is expedient by the simple impregnation process with aqueous solution can be achieved is about 35 percent by weight, although larger amounts may also be used can be incorporated into the intermediate concentrate through dry admixture.

The concentrate according to the present invention is then dried before further treatment and mixed with the diluting carrier material or partially or completely reduced or calcined before this mixing process. In each case, the catalyst is finally in air at temperatures of 38-370 ° and dried at temperatures of up to 480-540 ⁰

slowly annealed. But you can also reduce the mixture of the dried substances with high flow rate hydrogen, while this mixture is slowly heated ^{from room temperature to 480 to 540 0.} Using this process, the catalyst is preferably reduced in the hydroforming unit by a stream of hydrogen or hydrogen-rich gases while the temperature is slowly increased, e.g. B. by 27 to 42 ⁰ in the

ίο hour, is increased. The heating speeds can also be a little slower or faster. The catalyst can also be calcined in air activated, but the heating speeds must then be controlled slowly and carefully to prevent deactivation.

Below are some typical examples of the present invention produced catalysts listed.

example 1

The standard comparative catalyst for this series of tests is a catalyst with 0.5% Pt on "H-41" clay, which was produced by impregnating the predried base material with dilute, aqueous chloroplatinic acid. To obtain a standard preparation, 1000 g of H-41 — Al ₂ O ₃ predried overnight at 12 ° are treated with 125 cm ^{3 of} an 10% H _{2 PtCl e} solution which had been diluted to 900 cm ^{3 with water.} The mixture was mixed well at room temperature and well dried overnight at 121 ⁰ further dried. The catalyst was then placed in pill form and was in the unit for reduction and ready to run. This preparation is hereinafter referred to as catalyst (1).

For the preparation of the intermediate concentrate in this example 1000 g at 121 ° predried "H-41" -clay with 850 cm ³ of an aqueous solution treated containing 131 g of chloroplatinic acid, dried first for 24 hours at room temperature and then overnight at 121 ⁰ dried. A portion of this 5 ° / ₀ Pt on alumina containing catalyst was retained for further experiments.

70 g of the catalyst concentrate prepared in this way were intimately mixed with 630 g of “ H-41” clay and put into pill form for test purposes. The concentrate (2) and the finished catalyst (3), which were produced in this way, represent concentrations of 5 and 0.5 percent by weight of platinum, respectively, based on the

Total amount of clay applied in this way. the Effectiveness and stability of these two catalysts in a standard hydroforming experiment were compared with the corresponding properties of the standard preparation (1).

In this test procedure, a heavy crude gasoline boiling at 93 to 166 ° is hydroformed over the catalyst pills used in the quiescent bed for 4 hours at 14 atmospheres at 480 ° with a hydrogen feed rate of about 108 m ³ to 1 hl of gasoline. This reaction period was followed by a 2 to 4 hour long oxidative regeneration at atmospheric pressure and a maximum temperature 480-510 ^0, starting with a gas from i ° / _o sodium oxygen concentration and the concentration stages to a final value of 2O ° / ₀ oxygen in the regeneration gas is increased. The resistance of the catalyst is measured by the decrease in the octane number per working period, the octane number changing with the feed rate. From a durability standpoint, the best catalysts appear to be those that keep this loss of effectiveness as low as possible.

Table II

Pt content
g / 1000 g
Kataly
sator Loading
kungge
sclrwin-
age.
V / V / h Octane number
(without
Additive)
total
liquid stability catalyst with rain
generation,
% of
Ver
equal
cataly- sators (i) 0.5% Pt on »H-41«, Comparison 5 I. 90 to 95 catalyst 100 (2) 5% Pt 50 2 96 "H-41" ... 175 (3) 10% of 5% pt 5 I. 94 "H-41" ... 175

Example 2

These data show that the catalyst (3) prepared via the intermediate concentrate (2) according to the invention has a very good activity which is close to that of the 5 ° / _o by weight concentrate. In this connection it should be noted that the catalyst (2) shows the tendency to be overactive and to result in large exothermic reactions and excessive hydrogenative cracking. The durability of the catalyst (3) is accordingly improved, and these results are obtained without increasing the total amount of platinum in the catalyst compared to the amount of platinum in the example of the Staridard comparative catalyst.

A 5 weight percent platinum on alumina concentrate was prepared in the same manner as catalyst (2) described above; 100 g of this mixture were dried first at room temperature and then at 120 ° for 16 hours and then reduced in a stream of hydrogen overnight. The reduction temperature was gradually increased from 120 to 480 ° over a period of 7 hours and held at 480 ° for a total of 22 hours. The final, prepared in this manner 5 ° / _o sodium catalyst was cooled to room temperature and mixed 41-H «-alumina with 900 g of pre-dried". The mixed catalyst was thoroughly mixed by means of a pulverizer, then made into a pill form and tested in a comparative experiment.

This catalyst was found to be {4) a possessed high effectiveness and with good catalyst resistance a product with a test octane number of 94 (without addition). The test results for this previously reduced ■ Concentrate (4) are listed in Table III, where they are compared with the catalysts of Example 1 can be.

Table III Concentrate and Diluent are both active clay

catalyst

(i) I (a) I (3) I (4) I (5) I (6) | (7) I (8)

Experiment No. 40 S 40 I 251 I 255 I 431 j 435 I 434 I 432 I 433

Platinum carrier

Platinum content, percent by weight

Parts based on 100 parts of total catalyst

Diluent for the catalyst

Parts based on 100 parts of total catalyst

Remarks:

Pt reduced before mixing

Working conditions:

Temperature, ° C

Pressure, kg / cm ²

- -Ha-HC molar ratio ..

Loading speed, V / V / hour

Duration of the working period, hours

* ° Condensate received from the system:

Octane test, without addition

Reid vapor pressure,

kg / cm ²

H-4I H-41 H-41 H-41 H-41 H-41 0.5 5 5 5 33Vs 33V3 100 100 IO IO i, 5 i, 5 - "- H-41 H-41 H-41 H-41 - - 90 90 98.5 98.5 no no no Yes no Yes 480 482 482 475 482.5 479 14th 14th 14th Ή 14th 14th 6th 6th 6th 6th 6th 6th I. 2.4 1.2 2 I. 2 2 4th 4th i, 5 2 i, 5 95, i 9 ⁶ > 3 93.8 82.9 94.3 85.7 0.42 0.63 o, 3i 0.91

H-41

H-41
90

Pills
Yes

480

14th
6th

87.6

H-41

H-41
90

Pills
no

483 486 483

14th
6th

85.1

14 14

β! 6th

I 2

86.3! 77.3

: 0.311

403 14

76.3

48;

1.5

76.3

483

14 6

75.9

If you consider the effect of the loading speed taking into account, the previously reduced catalyst comes close to the effectiveness of the initial one Preparation (3) where the concentrate is mixed with the diluent before the reduction had been.

Example 3

In this case, an intermediate concentrate with a high platinum content was prepared by impregnating 10 g of "H-41" clay with 12.5 g of chloroplatinic acid, which had been ^{made 8 cm 3 of solution with distilled water.} These amounts correspond to g of platinum or a concentrate of 33%. 11.7 g of the concentrate prepared in this way and containing 2.5 g of platinum were diluted with 490 g of predried "H-41" clay. This material was mixed thoroughly, pill-formed, and tested as described above. This catalyst, identified as (5) in Table III, was found to have good activity and stability at a product octane rating of 88.

Furthermore, a catalyst (6) was prepared using a previously reduced concentrate. In this case, 11.7 g of 33 ° / o platinum concentrate a total of 22 hours reduced as finished treated as in Example 2, and at 510 ^0th This mixture was mixed with 490 g of "H-41" clay, made into pill form and tested. In this case, the previously reduced concentrate results in

game 2 a catalyst with almost the same effectiveness as if the catalyst after mixing is reduced.

Example 4

The importance of intimately mixing the concentrate with the diluent results from the Values obtained by using individual pills made from concentrate and diluted clay with the same Total ratio applies as it has the above mixed catalysts.

Table IV gives values for the catalyst (7) for which 50 cm ^{3 of} the 5 oxigenic Pt concentrate pills (catalyst 2) were ^{mixed with 450 cm 3} "H-41" pills and used in the test facility. The catalyst (8) has the same proportions; in this case the concentrate pills were reduced and placed in the pilot plant before mixing. These two catalysts show only moderate results and indicate that thorough mixing is important whether or not the impregnated concentrate is reduced beforehand.

TabeUe IV Carriers other than active clay

Platinum carrier

Platinum content, percent by weight

Parts based on 100 parts
Total catalyst

Diluent for the
catalyst

Parts based on 100 parts
Total catalyst

Remarks:

Pt before mixing
reduced

Working conditions:

Temperature, ⁰ C

Pressure, kg / cm ²

H ₂ -HC molar ratio

Loading speed, V / V / hour

Duration of the working period,
hours

Preserved from the plant
Condensate:

Octane check

Reid vapor pressure, kg / cm ²

(9)

430

(10)

490 catalyst

(H) I (12) I (13) I (14)

Attempt no.
572 I 246 1 451 I 248

T-75

0.5

100

no

478 479

14 14

6 6

66.1 2.4

66.8

.2.6

H-41

5 10

T-75 90

no

492

14th

6th

78.7 4.8

71.2 3.8 ZnO ALO,

o, 5

100

no

483 482

14 14

6 6

81.7
5.9

88.5
5.7

10

H-41

no

481

14th
6th

90.4
5.9

TiO ₉ .

o, 5

100

no

485 486

14 14

6 6

75.3 65.8 5.6 3.5

10

H-41 90

no

482 483

14 14

6 6

90.2 5.7

The above examples provide particular details for the preparation of an improved catalyst according to the invention in which both the concentrate base and the diluent are forms of active clay. While certain procedural measures are essential to the production of an improved catalyst, other conditions can be changed and need not be kept exactly at the values given in the examples. For example, the pre-drying of the 2-7

ground activated alumina at 100 to 510 ° and even up to 760 ^{0 for} 2 to 24 hours, the higher temperatures requiring shorter times. When impregnating, mixing the dilute chloroplatinic acid solution with the dried ground clay or other carrier can take from about 10 minutes to about 1 hour, while adding water, if necessary, to maintain the mixture in a pasty state; however, excessive addition of water should be avoided. Man

can leave the paste at room temperature for about 2 to 24 hours; then she can slowly are dried at a temperature of about 100 to 205 ° for about 8 to 24 hours, the higher temperatures require shorter times.

The clay used can, as stated above, be a relatively pure form of active clay, such as e.g. B. the described variety »F-io«. Pure active clays prepared by any other method, including preparations obtained via a clay sol or precipitated clay, or by coprecipitation or otherwise in admixture with various additives, are also suitable. Particularly good results are obtained with active clays precisely measured small amounts of silicic acid, usually about 1 to ii ° / ₀ SiO ₂ oxide; the described type »H-41« is a substance of this kind.

For the production of catalysts which contain larger ao amounts of platinum, larger amounts of chloroplatinic acid are used. For all these preparations, the amount of platinum is in the finished catalyst is preferably between about 0.1 to 1 weight percent, in exceptional cases also somewhat more (up to 2 ° / _0). Also, although chloroplatinic acid has been used herein as a readily available platinum salt, other soluble platinum salts can be used to advantage in the same general manufacturing process. Additional catalysts prepared by the same procedure using ingredients other than active clay as a carrier for the concentrate or as a diluent have also been tested, as shown in Table IV. These results generally show that the use of active clay as a diluent material is beneficial but not essential for the concentrate base. Indeed, in certain cases, superior catalysts are obtained by using those carriers for the concentrate which do not produce useful results when used as the sole matrix for catalysts with the same final platinum content.

Example 5

A catalyst (9) containing 0.5 weight percent Pt on alumina was prepared using some form of alpha alumina or corundum in place of active alumina. For this preparation 1000 g of "T-75" - alumina in tabular form (s. Table I) with 125 cm ³ of a io ° / ₀ solution of H ₂ PtCl ₆ stock solution impregnated, dried and examined. The catalyst gave poor results and a product with an octane rating of only 67.

Another catalyst (10) with the same basic mass was made by adding 60 g of 5% Pt (Catalyst 2) alumina powder to 540 g of "T-75" alumina manufactured. The material was intimately mixed by regrinding, dried and examined. Although the octane number in this case was only mediocre and was 79, this represents a significant improvement compared to the results obtained with the catalyst (9), in which the base material "T-75" was used alone.

Example 6

A zinc aluminate matrix was made by mixing a solution of 23 kg of zinc sulfate and 41 concentrated sulfuric acid in 1101 water with a nitrated solution containing 27 kg of sodium aluminate and 3.2 kg of NaOH in iiol water. The resulting zinc aluminate precipitate was filtered, washed on a filter press and stored at 205 ° dried.

A catalyst (11) with 0.5 weight percent Pt on Zinkaluminatgrundlage was prepared by impregnating 600 g of the above dried precipitated with 75 cm ³ of a io% strength n ^e, with distilled water to 800 cm ³ HgPtClß stock solution diluted prepared. The resulting paste was dried at room temperature and at 120 ° and made into pill form for research purposes.

A comparative catalyst (12) for this was obtained by first producing a 5% Pt concentrate on the zinc aluminate. Here, 12.5 g of chloroplatinic acid crystals (40 ° / ₀ Pt) were dissolved in 80 cm ^{3 of} distilled water, added to the base material and mixed with this thoroughly to form a paste. This paste was dried at room temperature and at 120 °, and 900 g of »H-4iff clay that had been pre-dried at 345 ° were added. The whole was mixed by grinding and formed into 1200 cm ^{3 of} catalyst pellets for experimental purposes.

In this case the zinc aluminate alone was not a good carrier; but the catalyst (12) with “H-41” as a diluent and zinc aluminate as a carrier for the concentrate showed quite good effectiveness.

Example 7

A similar comparison shows even more surprising results when activated titanium dioxide is used as the carrier. A catalyst (13) with 0.5% Pt on titanium dioxide obtained from titanium hydroxide was produced by the same impregnation process as described above. This catalyst was poorly effective but was very poorly persistent as indicated by the decrease in product octane number which, as shown in Table IV, instead of the usual increase in the second run at the lower feed rate of 1 v / v / hr. is to be determined. The same titanium dioxide resulted when used as base material for a 5 ° / _o sodium concentrate, such as H-41 was diluted «-alumina previously with 10 parts to 90 TeUe", a catalyst (14) with a comparatively excellent initial activity and good stability.

The above figures represent test results with the catalyst used in the quiescent bed; however, the results of the present invention are of course particularly advantageous if iao works according to the fluidized bed process.

The platinum-containing catalysts prepared by the special process described above give ^{better results at high pressures of about 35 to 70 kg / cm 2} when they are used in hydroforming reactions, but are at lower pressures

in the range from 3.5 to about 17.5 kg / cm ^{2 are} particularly effective in terms of their high resistance to regeneration.

Claims (6)

Patent claims: 1. Process for the preparation of a hydrocarbon conversion catalyst with 0.01 to ίο about I percent by weight of a precious metal, e.g. B. 0.1 to i ° / o platinum, and one containing alumina Mixture, characterized in that you first an intermediate concentrate by applying a Connection of the noble metal on a solid oxidic carrier is established by this soaked with a water-soluble compound of the noble metal in such an amount that the concentrate ι up to 35 percent by weight of the noble metal, based on the total weight of the noble metal and the carrier, the concentrate dries and then finely divided with a predominant amount pre-dried clay or substances or mixtures containing clay in such quantities diluted so that the finished mixture has the total content of noble metal specified above. 2. The method according to claim 1, characterized in that that the catalyst support is an oxide of aluminum, silicon, magnesium, titanium, zirconium, Thorium or zinc or a mixture of these oxides. 3. The method according to claim 1 and 2, characterized characterized in that the alumina-containing additives used for dilution are adsorptive and preferably consist of active clay. 4. The method according to claim 3, characterized in that as a diluent for the Pre-dried adsorbents containing alumina used for catalyst support impregnated with precious metal through smaller quantities of solid oxides, namely those of silicon, chromium, magnesium, Titanium, Zirconium, Thorium, Bors, Zinc, or by mixtures of these oxides in its catalytic Effect is enhanced. 5. The method according to claim 1 to 4, characterized in that the catalyst support is alumina and that the noble metal is platinum or palladium. 6. Process for the preparation of a hydrocarbon hydroforming catalyst according to claim ι to 5, characterized in that so much of a predried, alumina-containing Adsorbent mixed with your own amount of an adsorbent catalyst support, which has previously been soaked with a solution of a noble metal salt that the total mixture after Reduction of the metal salt about 0.01 to 1 percent by weight of the precious metal. © 609 550/413 T. (609 782 1.57i