DE2741209C2 - A catalyst containing a titanium fluoride component on a metal oxide of group III A of the periodic table, and its use - Google Patents

Description

The invention relates to a catalyst which has a titanium fluoride component on a metal oxide Contains group 111 A of the periodic table by treating the metal oxide activated by heating to a temperature below 600 ° C with tuante tetrafluoride, as well as the use of the Catalyst.

This is known from US Pat. No. 3,153,634.

Compared to this prior art, the object is to provide an improved catalyst of the specified Kind of creating that is particularly useful for the oligomerization of olefinic hydrocarbons suitable, and is easy to manufacture.

The object is achieved in that the metal oxide is an aluminum oxide containing surface hydroxyl groups, Gallium oxide, indium oxide or thallium oxide is used, which is produced by treatment with hydrogen or nitrogen has been activated at a temperature of 350 to 550 ° C, and that the treatment of the activated metal oxide with the titanium tetrafluoride Temperatures in the range from ambient temperature to 600 ° C takes place.

The catalyst according to the invention is used in particular for the oligomerization of terminal olefins with 3 to 6 carbon atoms.

As is also demonstrated by the examples given below, the catalyst according to the invention has an excellent ability to oligomerize the olefins. This, according to the known, unexpected ability for oligomerization brings with it a substantial technical enrichment of the technical field, since there is, as is well known, a pronounced interest in technology for such oligomerization products. For example, olefinic hydrocarbons with 6 to about 8 carbon atoms in the molecule have a wide range of applications. For example , hydrocarbons with 8 carbon atoms are used as high quality engine fuel components to increase the octane number. Similar hydrocarbons can be used as starting materials for the manufacture of plasticizers.

The preparation of the catalyst according to the invention requires, as evidenced by the above and The following information and examples are not cumbersome or time-consuming measures and are therefore like without further evident, to be carried out in a simple manner.

Features and preferred embodiments of the invention are further explained below.

A surface hydroxyl group is preferably used as the metal oxide containing gamma aluminum oxide low density and large surface area -

Specifically, the catalyst for oligomerization is "i tion of propylene at a temperature ranging from ambient temperature to 250 ⁰ C and a pressure ranging from atmospheric pressure to toobar used." The oligomerization takes place in the presence of a catalyst, which is produced by impregnating an r. Low density, high surface area gamma-alumina having surface hydroxyl groups has been prepared with a solution of titanium tetraf ^ oride in an organic solvent at a temperature in the range of about 200 to 450 ° C

In the preparation of the catalyst, an impregnation treatment or a sublimation treatment can be used to combine the thante tetrafluoride with the activated metal oxide.

. '". Of the metal oxides of group IH A des In the periodic table, aluminum oxide is the cheapest metal oxide, especially a higher aluminum oxide Surface size, such as gamma-aluminum oxide or possibly eta-aluminum oxide. The apparent bulk weight

The f of the aluminum oxide should be in the range from about ³ to 0.7 g / cm 3 and the surface area in the range from about 1 to 500 m ² / g. The alumina can have any suitable shape, such as spherical alumina particles

r. called. It can gasna-alumina commercially available Find application, this is then by treatment at 350 to 550 ° C with nitrogen or Hydrogen, suitably activated over a period of about 1 to 8 hours. A sharp drying

■> »of the metal oxide at higher temperatures must be avoided. For example, drying aluminum oxide at temperatures above about 600 ° C to impair or eliminate the surface hydroxyl groups on it.

When using the aforementioned sublimation treatment, it is advisable to first combine titanium irafluoride with the activated aluminum oxide at room temperature under a stream of nitrogen. The temperature is then increased to a value above the S.'blimation temperature (284 ° C) of the titanium tetrafluoride, a flow of substances is maintained in the downward direction. The Tempe: ature is then again increased, and in a series of steps to 35O ⁰ C to 400 C maintained for about ¹¹ 0.5 to 4 hours here.

An impregnation treatment is preferably used for the preparation of the catalyst. A solution of titanium tetrafluoride in water or an organic polar solvent is used. The desired amount of titanium tetrafluoride is dissolved in the solvent in an inert atmosphere, for example nitrogen, helium or argon. The activated metal oxide of group III A is then impregnated with the solution and expediently first circulated in the cold, ie without heating, for a while in the solution, followed by mild steam drying at about 100 ° C. while maintaining an inert atmosphere. The catalyst is then subjected to further drying at about 200 to 600 ° C

in an inert gas atmosphere, preferably with downward flow of the inert gas.

Instead of the aqueous titanium tetrafluoride solution, an aqueous solution of titanium hexafluorohydrohydric acid, which of course gives titanium tetrafluoride on decomposition, can be used. Impregnation using the aqueous titanium tetrafluoride solution or the aqueous titanium hexafluoric acid can also be carried out by impregnating the metal oxide with the solution, then advantageously circulating it cold in the solution for about 0.5 to 4 hours and then circulating it at a temperature of about 200 to 450 ^° C. For sufficient time to evaporate or decompose the aqueous solution and form the titanium tetrafluoride on the Group III A metal oxide-containing catalyst.

As group III A metal oxides, which have the necessary surface hydroxyl groups and also have a relatively large surface area, aacb gallium oxide, indium oxide and thallium oxide can be used.

The catalyst can also be combined with a solid support. Preferred carrier materials are in particular inert compounds with a large surface area, e.g. B. silica or mixtures of Silicon dioxide with other inorganic oxides, such as silicon dioxide-magnesium oxide, silicon dioxide-zirconium oxide, Silica-thoria and silica-magnesia-zirconia, Charcoal, charcoal, diatomaceous earth, and clays. These compounds only act as a carrier for the catalyst and do not carry contributes significantly to the catalytic activity of the catalyst. The catalyst off. Titanium tetrafluoride and the metal oxide of the group: ΠΙΑ can with a such carrier in any known manner, e.g. B. by impregnation, deposition. Rolling, grinding or mixing.

One or more promoters can also be added to the catalyst, e.g. B. Group metals VIB or VIII of the periodic table.

The catalyst is particularly suitable for the oligomerization of olefins which have 3 to 6 carbon atoms and a terminal double bond. The products obtained are, in particular, dimers and trimers of the monomeric olefin used. The olefinic hydrocarbon to be oligomerized is introduced into the reaction device which contains the catalyst under predetermined reaction conditions. Suitable reaction conditions are particularly temperatures ranging from ambient to about 25O ⁰ C, pressures ranging from atmospheric pressure to about 100 bar, and hourly space velocities of the liquid in the range of about 1 to 10. The to oligomierisierenden olefins may, if desired, in admixture with paraffins, as Diluents act for the implementation, are present. The olefins must not be ip. Mixture with an aromatic diluent, provided that the latter is not highly alkylated.

example 1

A titanium hexafluoric acid solution was prepared by diluting 6.58 g (4.05 ml) of a 60% tilane hexafluoric acid solution to 350 ml with demineralized water. ^{300 cm 3 of} activated gamma-alumina was added to the titanium hexafluoric acid solution and circulated in it while cold for 10 minutes. The impregnated material was first steam-dried and then heated for a further 2 ^> hours at a temperature of 300 ^° C. in a nitrogen atmosphere. The final catalyst was exposed to air for 12 days and then again dried for 4 hours in a downward flowing nitrogen stream at 300 ° C

30 cm ^{3 of} the catalyst were introduced into a tubular glass reactor. A mixture of propene and helium was passed over the catalyst at 200 ° C. for 2 hours. The reaction product was condensed at -78.5 ° C and then analyzed by chromatography. The composition of the product obtained in terms of (V carbon atom skeletons, given in percent by weight, is shown in the table below.

33-dimethyl-1-butene 03 4-methyl-1-pentene \ 3-methyl-1-pentene J. & ■ Ί-methyl-cis-2-pentep. 1.4 23-dimethyl-1-butene 4.4 unknown traces 4-methyl-trans-2-pentene 53 unknown 0.7 1-witches 1 2-methyl-l-petien J. 92 2-ethyl-1-butene 1 trans-3-hexene> 5.0 cis-3 witches j trans-2-hexene 42 2-methyl-2-pentene 1 70 7 cis-3 witches j Ji-J, / 3-methyl-cis-2-pentene 123 3-methyl-trans-2-pentene 20.1 unknown 02 23-dimethyl-2-butene 10.8

Example 2

The catalyst was prepared in a similar manner to Example 1. A high surface area activated gamma-alumina was impregnated with a solution of titanium hexafluoric acid. Drying was carried out for 16 hours at 450 ⁰ C. The finished catalyst was used for the oligomerization of propene helium feed, the oligomerization was carried out at a temperature of 250 ⁰ C and a feed of 4.06 g of propene per 100 minutes. The product was collected at a temperature of -78.5 ° C and analyzed by chromatography. The CV carbon atom skeleton distribution of the product obtained, given in percent by weight, is shown in the table below:

3,3-dimethyl-1-butene

4-methyl-1-pentene

3-methyl-1-pentene

4-methyl-cis-2-penia

2,3-dimethyl-1-butene

unknown

4-methyl-trans-2-pentene

unknown

1 witches

2-methyl-1-pentene

2-ethyl-1-butene

trans-3-hexene

cis-3-witches

03
1.7

1.0
3.2
4.1
3.9
13.4

12.8
43

trans-2-hexene

2-methyl-2-pentene \

cis-2 witches J.

3-methyl-cis-2-pentene

3-methyl-trans-2-pentene

unknown

23-dimethyl-2-baten

4.4
17.6

8.7

14.2

0.8

9.6

Example 3

The catalyst was prepared by dissolving 634 g of indium oxide in 500 ml of a nitric acid solution. 100 cm ^{3 of} granular silicon oxide gel was added to the solution, and the solution was then slowly neutralized with an ammonium hydroxide solution until a pH of 6 was reached. The solution was then evaporated in a steam heated rotary dryer and the resulting metal oxide was calcined for 4 hours in air at 450 ⁰ C. For further preparation of the catalyst, 53 cm ^{3 of} activated metal oxide ^{material were impregnated with 50 cm 3 of} a titanium hexafluorohydric acid solution which had been prepared by diluting 1 ml of the 60% aqueous titanium hexafluoric acid solution to 50 ml using demineralized water. After the impregnation, the product was dried by slowly heating it to 350 ^° C. and maintaining this temperature for 10 hours while gaseous nitrogen was passed over the catalyst.

The catalyst was placed in a vertical tubular glass reactor, and a mixture of helium and propylene was passed downflow at 200 ⁰ C through the reactor. The feed rate was 10 ml helium per minute and 35 ml propylene per minute. The product was collected at -30 ° C and analyzed by chromatography. The main carbon atom skeleton distribution of the Q-Cir product was: 7.4 percent by weight 23-dimethylbutane, 24.5 percent by weight 2-methylpentane. 203 weight percent 3-methylpentane. 25 percent by weight n-hexane, 2.5 percent by weight 2,4-dimethylpentane, 2.84 percent by weight ..? 2-methylhexane. 63 percent by weight 23-dimethylpentene, 33 percent by weight 3-methylhexane, the remainder consisted of various other isomers.

Claims (2)

Patent claims: 1. Catalyst containing a titanium fluoride component on a metal oxide of group Hl A of the periodic table, prepared by treating the metal oxide activated by heating to a temperature below 600 ° C with titanium tetrafluoride, characterized in that the metal oxide having a surface hydroxyl group is aluminum oxide, gallium oxide. Indium oxide or thallium oxide is used, which has been activated by treatment with hydrogen or nitrogen at a temperature of 350 to 550 ⁰ C, and that the treatment of the activated metal oxide with the titanium tetrafluoride at temperatures in the range from ambient temperature to 600 ° C takes place. 2. Use of the catalyst according to claim 1 for the oligomerization of terminal olefins with 3 to 6 carbon atoms.