JPS6094923A - Improved synthesis of 1-butene by dimerization of ethylene - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The subject of the present invention is an improved process for the trimerization of ethylene to 1-butene.

Prior Art and its Problems In U.S. Pat. No. 2,943,125, Chigu Y-
(K SZ Iegler) describes a process for the bifurcation of ethylene to 1-butene using catalysts obtained with mixtures of 1-realkylaluminum and titanium or zirconium tetraalcolades. During this reaction, too, a considerable amount of high molecular weight polyethylene is formed which cannot be used at all. Several improved methods have been proposed to reduce the polymerization rate.

In particular, U.S. Pat. No. 3,686,350 recommends the use of organic compounds of phosphorus as a component of the catalyst, and U.S. Pat. No. 4,101,600 claims treatment of the catalyst with hydrogen or In patent No. 3879485, the reaction l! ! ! The patent claims the use of various ethers as quality solvents.

These modifications of the original catalyst system have resulted in substantial improvements in the selectivity of the reaction, especially in industries where the 1-butene must be able to be separated from the solvent leaving only traces of polar compounds in the butene. It turns out that this is a very impractical method.

The aim of the present invention is to describe catalysts which exhibit particularly good activity and selectivity.

SUMMARY OF THE INVENTION The present invention relates to an improved method for converting ethylene to 1-butene, which converts ethylene into alkyl titanium-1-butene.
- and an alkylaluminum compound, wherein the catalyst is pre-contained with an alkyl titanate and an ether in an ether/titanate molar ratio of 0.5:1 to 10:1. A method characterized in that the mixture formed is obtained by interacting with an aluminum compound of the formula ΔlR3 or AIR2H, in which each residue R is a hydrocarbon group. be.

Therefore, the ethers are used in a molar ratio of 0.5 to 10, preferably 1 to 3, more specifically 2 mol of ether, per 1 mol of titanium compound. Although there is no theoretical support for ether, it is believed that titanium is self-associating (autoassoc).
It can be considered that it is complexed to the titanium atom while allowing hexacoordination that is not performed otherwise. If ether is used in a ratio of more than 10, for example 20 or more, or if it is used as a reaction solvent, the reaction will be very slow and its selectivity will be poorer, It turns out that sometimes no reaction occurs at all.

The aluminum compound used to prepare the catalyst has the general formula AlRa or A I R21-1, where R
is a hydrocarbon group, preferably an alkyl group having 2 to 6 carbon atoms), such as triethylaluminum, tripropylaluminum, triisobutylaluminum, hydrided cytubdelaluminum, 1 to
Lihexyl aluminum.

The needles used in this invention may be mononeedles or polyneedles. For example, diethyl ether, diisopropyl needle, dibutyl ether, methyl t-rubutyl ether, di-1-lahydrofuran, 1,4-dioxane, dihydropyran, and ethylene glycol dimethyl needle may be used.

Exceptional results were obtained using tetrahydrofuran and/or 1,4-dioxane.

The alkyl titanates used in this invention have the general formula T i (OR-)'4, where R' is preferably 2
a straight-chain or branched alkyl group having ~8 carbon atoms). For example, tetraethyl titanium 1~, tetraisopropyl titane 1~, te 1~ra n-butyl titanate 1~, and te 1~ra 2-ethylhexyl titane 1~ may be used.

The catalyst components may be contacted with the hydrocarbon and/or one or more oligomerization products, such as hexene, preferably in the presence of ethylene. The molar ratio between the aluminum compound and the titanium compound is approximately 1=1 to 20:
1, preferably about 2:1 to 5:1. The titanium concentration in the solution thus prepared is advantageously between 10-4 and 0.5 mol per 11, preferably 2X10 mol per 11.
-3 to 0.1 mol. The temperature at which the catalyst is prepared is usually -10 to +80°C, preferably -10 to +45°C.
, more preferably 0 to +40°C. When ethylene is present in the solvent, the amount is preferably 83% at the temperature.
It corresponds to the saturation of the solution at a pressure selected from , and atmospheric pressure or higher.

The IC reaction solution thus obtained may be used as it is, or may be diluted by adding a reaction product.

The ethylene dimerization reaction may be carried out at 20 to 150°C, preferably 20 to 70°C, more preferably 50 to 70°C. The pressure is preferably between 0.5 and 8 MPar.

In a particular method using a discontinuous catalytic dimerization reaction, a selected volume of the catalyst solution prepared as described above is introduced into a reactor equipped with the usual equipment for stirring and cooling. It is then pressurized with ethylene, preferably at a pressure of 0.5-8 MPa, and the temperature is reduced to 20-70'C, preferably 5
Maintain temperature between 0 and 70'C. The total volume of liquid produced is
represents 2 to 50 times the volume of catalyst solution initially introduced.
Ethylene is supplied to the reactor at a constant rate until lj; The catalyst is then destroyed, for example by adding water. The reaction product and optionally the solvent are then removed and separated.

Continuously operated lifting platform, preferably the following J: sea urchin. The catalyst solution is injected simultaneously with the ethylene into the stirred reactor in a conventional manner or by external recirculation. The temperature is maintained at about 20-70°C, preferably 50-70°C.

) 1 force is preferably 0.5 to 8 MPa. A portion of the reaction mixture flows through a pressure reducing valve, which maintains the pressure constant, with a quality tl'aUH equal to the mass flow rate of the fluid introduced. The fluid thus reduced in pressure is sent to a distillation column apparatus. With this device, 1-butene can be separated from ethylene on the one hand.

This ethylene is sent back to the reactor. On the other hand, 1
- Butene can be separated from hexene and A-ctene. A portion of these is sent back to the catalyst preparation section. The catalyst and bottoms containing heavy products may be incinerated or the recovered catalyst may be recycled.

In a preferred method of implementation, the catalyst components are mixed under an ethylene atmosphere at a temperature of -10 to +45°C. The temperature is then raised to 50-70°C to continue the dimerization reaction. More preferably, the mixed components of the catalyst are -1
The temperature is maintained at 0-145°C for 30 seconds to 24 hours, and then the temperature is increased to 50-70°C.

Effects of the Invention Since the present invention is configured as described above, it has the following effects.

The catalyst used in the present invention exhibits particularly excellent activity and selectivity. This effect is similar to Boss Fights 1-
ethers or amines, and when the ethers are used in amounts corresponding to their use as solvents or hydrocarbyl aluminum. The effect is more pronounced than that produced by J: on ethers when added after mixing with alkylditane-1.

This method also presents the advantage of omitting the use of these ethers as solvents, whose disadvantages, among other things, difficulties in separation have been noted. It even allows you to avoid things. The components of the catalyst are mixed directly into one of the products or by-products of the reaction. This avoids consumption or recycling of the solvent, which is always difficult to separate from the mixture resulting from A ribomerization.

EXAMPLES The following examples illustrate the invention but do not limit its scope.

Example 1 Temperature can be adjusted to 18°C by water circulation2
Into a stainless steel Grignard-type J-t-crepe with a capacity of 250 mQσ and equipped with a heavy mantle, the following items are sequentially introduced under an ethylene atmosphere. 2.5 m of 1-ethyl aluminum solution in hexene fraction prepared by mixing 0.25 me of 1-ethyl aluminum and 9.75 mQ of hexene, 0.05 m of 1-ethyl aluminum and 0.05 m of n-butyl titanate and tetrahydrofuran. 0.024.d and the hexene fraction 2.4.
The molar ratio between 2 mL TeI and Ditane 1 is 2.1:1. , phase Z-r for 2 minutes, temperature at 55° C. and ethylene pressure at 2 MPa.

After two and a half hours of reaction, the introduction of ethylene is stopped and the catalyst is destroyed by injection of two drops of pressurized sewage. 133 ethylene in total
consumed g.

In addition to unreacted ethylene, 0.28 g of n-butane
, 1-butene 92.40! J, hexene 6.469, octene 0.17g and polyethylene 0.0027≦1
Collect. Analysis of the C4 fraction by gas chromatography using a flame ionization detector shows a total 2-buten content of less than 101)l1m. Polyethylene is 271)
It shows 11m.

Under these conditions, the productivity of the catalyst increases to 130,889 1-butenes per 19 metal titanium.

EXAMPLE 2 (COMPARATIVE EXAMPLE 1, NOT PART OF THIS INVENTION) In the same equipment used in Example 1, a cell ratio of tetrahydrofuran to titanate of 1 (thus a tetrahydrofuran to titanate cell ratio of 2) was introduced. Instead of .j:1, make it 20:1, and make all the numbers the same as +!i!l 1.

No total conversion of ethylene was observed at 55°C after 5111 hours.

Example 3 (Comparative Example 1, not part of the present invention) Using the same equipment as used in Example 1, introducing more than twice as much titanium compound, more than twice as much aluminum compound, and no tetrahydrofuran. The other conditions were the same as in Example 1, and 91.69 g of 1-butene, 11.8 g of butane O,'2B9, 11.8 g of hexene, 0.68 g of l-ctene, and 0.1 g of polyethylene were obtained. 1-butene is 2-butene 360
Contains ppm. The productivity of the catalyst is only 65,009 butenes per gram of titanium metal.

Example 4 (Comparative Example 1, not part of this invention) Hexene was prepared by mixing 0.25i of triethylaluminum and 9.75me of hexene under ethylene stimulation in the same apparatus used in Example 1. 2.5 d of triethylaluminum solution in the distillate, then 0.024 d of tetrahydrofuran
d.

Finally, a solution of Teller n-butyl titanium 1 to 65* in 2.42 mQ of hexene fraction is successively introduced.

The reaction was then carried out under the same conditions as in Example 1 and according to the same procedure as described in Example 1.

Catalyst productivity is 1-butene 55 per gram of titanium metal.
It weighs only 92g. Polyethylene is 70 ppm.

EXAMPLE 5 (COMPARATIVE EXAMPLE 1, NOT PART OF THE INVENTION) Into the same apparatus used in Example 1, the following are introduced sequentially under an ethylene atmosphere. It was prepared by mixing 0.25 m of triethylaluminum and 9.75 m of hexane [2.5 mQ of 1 to ethyl aluminum solution in hexene fraction, then 2.42 m of tetra-n in hexene fraction. -Butyl・
Titanate 0.05m solution, and finally tetrahydrofuran 0.024d.

The reaction is then carried out under the same conditions as in Example 1 and according to the same procedure as described in Example 1.

The productivity of the catalyst is 923% for 1g of metallic titanium and 1-butene.
It's only 1g. Polyethylene shows 42 ppm.

Example 6 In the same apparatus as in Example 1, the temperature was set to 18°C under an ethylene atmosphere.
Maintain at ℃ and introduce the following in sequence. 2.5 mQs of triethylaluminum solution in hexene fraction prepared by mixing 0.25 m of triethyl aluminum and 9.75 Id of hexene, then 1 to 0.05 ml of tetran-butyl titanate and 0 to 1,4-dioxane. .025m1!
A solution of tetra-n-butyl-1,4-dioxane ditanate 1-complex prepared by mixing and a hexene fraction of 2.42 ml11. .07:1. After 2 minutes of interaction, the temperature is brought to 55° C. and the ethylene pressure to 2 MPa.

After 2.5 hours of reaction, the reaction was stopped by introducing 2 mQ of water under pressure. A total of 120Q of ethylene was consumed.

In addition to the unreacted ethylene, collect the following:

0.18y of 1-butane, 87.09g of 1-butene, 6.88g of hexene, 0.20g of octene, and 0.0042SF of polyethylene.

The C4 fraction contains 2060 ppm butane and 10 ppm
Includes total 2-butene percentage under TIl j. Polyethylene represents 451)rllll.

Catalyst productivity is 123 1-butene per 1 titanium metal.
It reaches up to 36 shi.

Example 7 In the same apparatus as Example 1, the temperature was set to 1 in an ethylene atmosphere.
While maintaining the temperature at 8°C, introduce the following in sequence. A solution of 1.25 mQ of triethylaluminum in 1c hexene fraction was prepared by mixing 0.5 me of triethyl aluminum with 9.5 d of hexene, and then 0.05 mQ of n-butyl titanate was mixed with 0.05 Id of glym. The molar ratio of n-butyl-glyme (ethylene glyc]yl dimethyl ether) Ditane 1 to Ditane 1 to lead-free solution d5 and 2.5 mg of Hekihin distillate was prepared by mixing. The ratio is 3.2:1.

After 2 minutes of interaction, the temperature is brought to 55° C. and the ethylene pressure to 2 MPa.

After 2 hours of reaction, the catalyst was broken down by adding 2 m (l) of water under pressure. A total of 136 g of ethylene was consumed.

In addition to the unreacted ethylene, the following are recovered. 0.22 g of n-butane, 89.28 g of 1-butene, 9.83 g of hexene, 0.41 g of octene and 0.0139 g of polyethylene. C4 fraction is n-butane 2400
pllIII and a total 2-butene rate of less than ioppm. Polyethylene shows 1399F)m.

The productivity of the catalyst is 1-butene 126 per gram of titanium metal.
It reaches up to 46y.

Example 8 (Comparative Example 1, not part of the present invention) Same equipment as in Example 5, except that the amount of RL-butylglyme introduced was changed so that the molar ratio of glyme to titanium was 230 instead of 3°2=1:
1, and all other points were the same as in Example 5.

The productivity of the catalyst is then only 1350 g of 1-butene per gram of titanium metal.

Example 9 In the same apparatus as in Example 1, the temperature was set to 18°C under an ethylene atmosphere.
℃ and introduce the following in sequence: 2.3rd h-triethyl aluminum solution in hexene fraction prepared by mixing 0.5 me of triethyl aluminum and 19.5 m of hexene.

Then n-butyl ditaneous 1-0.4d and hexene 1
9.6d of dihydropyran 1-complex solution prepared by mixing 0.215d of dihydropyran. The molar ratio of dihydropyran to ditane is 2
:1.

After 2 minutes of interaction, the temperature is increased to 55° C. and the ethylene pressure is increased to 2 MPa.

The catalyst is destroyed after one and a half hours of reaction.

The recovered product contains 6 1-butenes per gram of titanium metal.
This corresponds to a productivity of 146 g of catalyst.

Example 10 In the same apparatus as in Example 1, the temperature was increased to 3 in an ethylene atmosphere.
The temperature was maintained at 5°C, and the following components were introduced in sequence. Triethyl aluminum 0.5me and hebutane 19. 2.5d of triethylaluminum solution in heptane prepared by mixing '5me.

Then, a solution of isopropyl-1°4-dioxane ditanate I, prepared by mixing 0.34.7 isopropyl titanate and 0°2-1,4-dioxane in 19.4 d of heptane, was added to 2.5 mf2O dioxane. The molar ratio of Axane to Ditane 1- is 2:1.

After 5 minutes of interaction, the temperature was brought to 70° C. and the ethylene pressure was brought to 3 MPa. The catalyst was destroyed after 2 hours of reaction.

The productivity of the catalyst is 1-butene 850 per gram of titanium metal.
It is 0 g.

Continuing from page 1 ■Int, C1,' Identification symbol Internal organization i Priority claim [Phase] September 20, 1984 [Phase] France (FR) ■
831 @ Inventor: Dominique Comlouf, France. Abel Voucher Peck (78230) Abnew du Gilaire 6
street address

Claims (1)

[Claims] (1) An improved method for converting ethylene to 1-butene, which comprises contacting ethylene with a catalyst obtained by the interaction of an alkyl titanate (1) with a fulkylaluminium compound. In a method in which the catalyst converts a preformed mixture of Al:1-nylbutane-1 and ether in a molar ratio of 0.5 = 1 to 10:1 of ether/titane-1 to AlR3 or A I A method characterized in that it is obtained by interacting with an aluminum compound represented by R21-1 (in the formula, each residue R is a hydrocarbon group). (2) The method of claim 1, wherein the molar ratio of ether to alkyl titanate is about 1 to 3:1. (3) A method according to claim 1 or 2, wherein the interaction is carried out in a solvent consisting of hexene recovered as the 'r, □v1 product of the reaction. (/l) Needle is diethyl ether, diisopropyl ether, dibdel needle, methyl tertiary butyl ether, tetrahydrofuran, 1゜4-diAkizan, dihydrobilane or ethylene glycol dimyl ether, claim 1・The method described in any one of the three items. (5) The method according to claim 4, wherein the ether is 1,4-diokylene. 6) The method according to claim 4, wherein the ether is tetrahydrofuran. (7) The interaction of the aluminum compound with the preformed mixture of alkyl titanate and ether is -1
It is carried out under an ethylene atmosphere at a temperature of 0 to +45 °C, and after heating, 5
7. A method according to any one of claims 1 to 6, wherein the temperature is between 0 and 70<0>C. (8) Bring the mixed components of the catalyst to a temperature of -10 to +45°C.
8. The method of claim 7, wherein the temperature is maintained at 50-70<0>C for 0 seconds to 24 hours. (9) The molar ratio between the aluminum compound and the titanium compound is 1:1 to 20:1, and the titanium concentration is 10-4 to 0.5 mol per 11 when using a catalyst, and 20
Conversion of ethylene into 1-butene at a pressure of 0°5 to BMPa at a temperature of ~150°C! 9. The method according to any one of claims 1 to 8, wherein the method comprises: (10) The method according to claim 9, wherein the temperature is 20 to 70°C.