DE1234196B - Process for the preparation of catalysts containing aluminum and chlorine - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

BOIj

German KL: 12 g -11/64

Number: 1234196

File number: B 68792IV a / 12 g

Filing date: September 10, 1962

Opened on: February 16, 1967

The subject of patent 1194 378, to which the present process is in an additional relationship, is the production of catalysts for carrying out reactions of the Friedel-Crafts type, especially on hydrocarbon compounds, by halogenation of aluminum oxide with halogen containing organic compounds. The main patent procedure is characterized by that activated aluminum oxide under non-reducing, anhydrous conditions with compounds the general formula

Cl

X-C-Cl

in which X and Y can be identical or different and denote H, Cl, Br, F and / or SCl or X and Y together denote O or S, at temperatures from 149 to 593 ⁰ C is so chlorinated that at most about 3 be attached to 3.5 x 10 ~ ⁴ g of chlorine per square meter of catalyst surface. According to this process of the main patent, the aluminum oxide is preferably treated with tetra-carbon, chloroform or methylene chloride. The catalysts can additionally contain a small amount of a metal or a metal compound with hydrogenation activity of groups VIa or VIII of the Periodic Table. It is z. B. passed a gaseous stream of the chlorine compound over the aluminum oxide, the rate of addition of the chlorine compound not exceeding 1.3 percent by weight of chlorine (based on the catalyst weight) per minute or the chlorine compound is in a non-reducing carrier gas stream, preferably nitrogen, air or oxygen, brought in. The flow rate of the carrier gas is at least 200 V / V catalyst per hour. A platinum metal-containing Aluminiumoxydgemisch is treated, conveniently at temperatures of 232-316 ° C, while a palladium-alumina mixture is treated at temperatures of 260-343 ⁰ C.

These novel catalysts are particularly suitable for the isomerization of hydrocarbons :. Substances of the gasoline boiling range, ie up to 204 ⁰ C boiling C ₄ - and higher compounds.

The present invention relates to a further embodiment of the method from the main patent. It is characterized in that the chlorinated catalyst is then mixed with an oxygen-containing catalyst

Process for the production of aluminum and
Catalysts containing chlorine

Addendum to the patent: 1194 378

Applicant:

The British Petroleum Company Limited,

London

Representative:

Dr.-Ing. A. v. Kreisler, Dr.-Ing. K. Schönwald,
Dr.-Ing. Th. Meyer and Dr. JF Fues,
Patent attorneys, Cologne 1, Deichmannhaus

Named as inventor:

Thomas Campbell O'May,

Paul Anthony Lawrence,

Sunbury-on-Thames, Middlesex (Great Britain)

Claimed priority:

Great Britain 11 September 1961 (32 503)

Gas, preferably with air, treated at 260 to 680 ° C will.

The reason why this oxygen treatment is beneficial is not known with certainty. At first sight, the chlorination treatment, which causes the addition of chlorine to certain reactive surface groups with removal of oxygen atoms, should not lead to any reactions which make a subsequent oxidation treatment necessary. However, it has been found that oxygen treatment is extremely beneficial when the chlorinating compound contains sulfur - for example when thiocarbonyl tetrachloride, CCl ₃ SCl, is used as the chlorinating agent - or when the catalyst contains a platinum group metal. It is therefore assumed that the sulfur contained in the chlorination compound or present as an impurity in technical grades of other chlorination compounds reacts with the aluminum oxide or with the metal of the platinum group, a catalyst of lower activity being formed. It was also

709 509/429

put that as a product of the chlorination treatment Carbon oxide can be formed, which is known to be strongly chemisorbed by platinum and consequently the effective platinum surface is blocked. This sulfur or this carbon oxide is oxidized in the subsequent treatment step removed, whereby the activity of the catalyst is increased.

The oxidation is expediently carried out in air, but mixtures of oxygen with one or more inert gases can optionally also be used. It has been found that heating in an inert gas alone is useless. The temperature that is used must be far enough below the limit at which damage to the catalyst (for example conversion of the aluminum oxide, of the catalyst into α-aluminum oxide or crystallization of the platinum group metal which may be present) can occur. Therefore, the temperature range of 260 to 68O ⁰ C is selected. Preferred for the calcination temperatures in the range 260-538 ⁰ C, in particular 316 to 482 ° C. The duration of the calcination is preferably at least 1 hour, and may be in the range of 1 to 24 hours. The treatment with the oxygen-containing gas is called "calcination".

The other details of catalyst manufacture can be the same as those described in German Patent 1194,378. A a special feature is, for example, the special form of chlorination; in the case of active catalysts for the conversion. are formed by hydrocarbons at low temperature.

in the same way as catalyst A treated. After completion of the treatment with carbon tetrachloride, the catalyst was with Rinsed dry air (flow rate 500 V / V / hour) and the catalyst temperature 482 ° C and held at this level for 2 hours. The catalyst was then turned on under nitrogen Chilled to room temperature and placed in a dry, airtight container. Through the treatment ίο the weight of the catalyst had increased by 7.25%. The chlorine content of the freshly treated catalyst was 9.55 percent by weight.

3. Activity tests with catalysts A and B

The catalysts described above were tested for their low temperature isomerization activity. Processed was a degewed, dearomatized C _{e cut} from a refinery light gasoline containing 0.1 percent by weight of

also contained carbon trachloride as an additive. The activity test was carried out under the following conditions:

Temperature 132 ° C

Pressure .... 18.5kg / cm ³

Molar ratio H ₈ : HC 2.5: 1

^{as the} space velocity of the

Liquid insert 2.0 V / V / hour:

The activity of the catalyst was determined from the single pass conversion of the hexane in 2,2-dimethylbutane is determined, its amount in percent by weight of the unstabilized liquid product was determined. The results of the activity tests are shown in Table I.

2. Preparation of a fresh catalyst B

30 cm ^{3 of} a commercially available platinum-aluminum oxide catalyst containing 0.57 percent by weight of platinum and 0.81 percent by weight of chlorine on aluminum oxide

example 1
1. Preparation of a fresh catalyst A

30 cm ^{3 of} a commercially available platinum-alumina catalyst containing 0.57 percent by weight of platinum and 0.81 percent by weight of chlorine on aluminum oxide were treated as follows:

a) The catalyst was dried for 2 hours in flowing nitrogen at 26O ⁰ C. The space velocity of the gas flowing from top to bottom used in this treatment was 500 V / V / hour during the entire time.

b) The dried catalyst was impregnated with 24 weight percent (based on the catalyst), carbon tetrachloride-treated at 260 ⁰ C. The carrier gas was nitrogen, which was passed through a carbon tetrachloride "saturator" at room temperature. In this way, the required amount of carbon tetrachloride was passed in vapor form over the catalyst in 1 hour.

c) The treated catalyst was purged an additional hour with nitrogen at 26O ⁰ C and then filled into a dry airtight container. The treatment had increased the weight of the catalyst by 6%. The chlorine content of the freshly treated catalyst was 11.3 percent by weight.

Table I.

Conversion to 2,2-dimethylbutane 6th 12 I 18 19.5 in hours 45 mission in percent by weight of 20th 20th 25.5 36 19.5 3 catalyst unstabilized liquid product 24 24.5 20th 24.5 3 running time 24.5 A. B.

45 These results show that the calcination of catalyst B decreases its activity. was improved, as a result of which a conversion to 2,2-dimethylbutane was achieved per pass which was about 4 percent by weight higher than that of catalyst A.

Example 2

Preparation of Fresh Catalyst C
30 cm ³ of a commercial platinum-alumina catalyst comprising 0.57 weight percent platinum and 0.81 weight percent chlorine contained on alumina, were treated in the same manner as Catalyst B. In this case, however, the high temperature treatment was carried out under flowing dry nitrogen (500 V / V / h). The treatment resulted in an increase in the weight of the catalyst of 6.7%. The chlorine content of the fresh catalyst was 10.5 percent by weight.

Activity test of the catalyst C

The conditions of the activity test of the catalyst C were exactly the same as for the catalyst

Sators A and B of Example 1. The results obtained are shown in Table II below.

Table II
Activity test of the catalyst C

Conversion to 2,2-dimethylbutane, percent by weight
from the unregulated
Liquid product

Running time, hours 6 18 30 36

19.5

19th

19th

Activity test of catalysts D and E
The activity test conditions were the same as for Catalysts A, B and C. The results obtained are shown in Table III S below.

Table III

Conversion to 2,2-dimethylbutane in percent by weight of the liquid product:

30th

It can be seen that heating the catalyst in nitrogen brought no benefit and activity of the catalyst was the same as that of the untreated catalyst of Example 1.

Example 3
Preparation of a catalyst D

65 g of a commercially available platinum-aluminum oxide catalyst, which contained 0.57 percent by weight of platinum and * ⁵ 0.81 percent by weight of chlorine on aluminum oxide, were placed in an upright, tubular reactor and heated for 2 hours at 260 ^° C. under nitrogen containing 401 / Hours. was carried out, dried. _{13.6 g of thiocarbonyl tetrachloride (CCl 3} SCl) were added dropwise over a period of 16 minutes into the incoming nitrogen stream. The treated catalyst was then purged with nitrogen for an additional hour. After cooling to ambient temperature, the catalyst was quickly placed in a dry, airtight container. The treatment resulted in an increase in the weight of the catalyst by 7.1%. The chlorine content of the fresh catalyst was 11 percent by weight and the sulfur content was 0.47 percent by weight.

Preparation of a catalyst E

26 g of catalyst D were calcined for 1 hour at 482 ° C. in flowing air (401 / hour) and then cooled to ambient temperature and placed in a dry, airtight container. The chlorine content of the catalyst was 9.1 percent by weight, the sulfur content 0.33 percent by weight.

Catalyst D
Catalyst E.

Running time, hours 6 12 21 39

4.5
15.5

3
18.5

3
19.5

The particular advantage achieved by using the invention when used for chlorination The compound used contains sulfur is readily apparent from the values in Table III.

Claims (2)

Patent claims: 1. Process for the preparation of aluminum oxide and chlorine-containing catalysts for carrying out reactions of the Friedel-Crafts type, with activated aluminum oxide under non-reducing, anhydrous conditions with compounds of the general formula Cl X-C-Cl in which X and Y can be identical or different and are H, Cl, Br, F and / or SCl or X and Y together are O or S, is ^{chlorinated at temperatures of 149 to 593 0} C such that at most about 3 to 3.5 ■ 10 ~ ⁴ g of chlorine are deposited per square meter of catalyst surface area, according to Patent 1 194 378, characterized in that the chlorinated catalyst is then treated with an oxygen-containing gas, preferably treated with air at 260 to 68O ⁰ C. 2. The method according to claim 1, characterized in that the treatment with the oxygen-containing gas at 260 to 538 ⁰ C is carried out.