SU362527A1 - DESCRIPTION OF THE INVENTION'362527M. Cl. At 01J 11/84 C 07c 3 / 02UDK 66.097.3 (088.8) - Google Patents

Description

one

The invention relates to catalysts for dividerization or sodimerization of olefins in the liquid phase, and especially "high olefins with carbon atoms from 2 to 4. Particularly applicable is the catalyst for dimerization-propylene in order to obtain a product with a very high content of methylpenthenes, the pyrolysis of which gives dienes.

A known catalyst for dimerization or codimerization of Ov efinov, containing a halide of an organoaluminum compound and a complex of a transition metal halide of Group VIII of the Periodic System with organic compounds of trivalent metals, for example P, As, Sb.

Known catalyst has not enough high activity.

In order to increase the activity of the catalyst, a complex formed by a transition metal of group VIII halide with 1-6 molecules of organic sulfoxide or disulfoxide per atom of the transition metal is introduced into its composition.

The proposed catalyst as a transition metal may contain nickel, and as an organic sulfoxide, diphenyl sulfoxide, dicyclohexyl sulfoxide or 1.2-di- (methylsulfoxy) ethane.

The sulfoxide complex compound of the transition metal in the catalyst of the software (the proposed .vioMy method can be (P-represented by formulas like MHg-P Ri (SO) nR2 or

MHZ-P (RiSOR2SOR3), in which the M is a transition metal of Group VIII, and the preferred metals are iron, cobalt, ikel and copper, and especially nickel; X is halogen, in particular chlorine, bromine, iodine; P can take

values from 1 to 6. The number of sulfoxide molecules that can form a complex with MX2 depends on the conditions of the preparation of the complex; n can have values of 1 or 2; Ri and R2 groups of alkyl, cyclohexyl, aryl (they

may be identical or different).

The optimum activity of the catalyst is at the most easily controlled temperatures, i.e., equal or slightly distant from 0 ° C. Indeed, it is known that thanks

high latent heat of ice melting, just 1 ntr. and 0 ° C or near this temperature, it is easiest to keep constant the temperature of the medium of the exothermic reaction. Also in the vicinity of 0 ° C, catalysts improve the selectivity of dimers in relation to higher oligomers to 95% and higher. At this temperature, the dimers contain a high percentage (up to 70%) of methyl 2-1-pentene-2, which is especially valuable for the production of isolate.

The yield may exceed 200 kg / g nickel / h for continuous operations.

The rate of activation of the catalysts and, therefore, the reaction rate is improved without reducing the selectivity by adding to the catalytic system a small amount of water in an amount of O-2 mol H20 per 1 mol of an iciel complex. The limits must be strictly observed, because above these limits water has a detrimental effect, lowering the degree of selectivity.

Sulfoxide complexes based on transition metals (and mainly nickel) can be easily obtained according to the methods described in the examples. Very good results, kasayush, ies (Transformations, selectivity of dimero with respect to oligomers, reaction time, are obtained only when the catalyst contains a transition metal halide, which forms a complex with organic sulfoxide. If instead of a complex, use only a transition metal halide and an organoaluminum compound, the reaction goes much more slowly.

If you take halide n, ikel, you need 24 minutes in the presence of 6 water molecules to obtain a 90% yield. The content of higher oligomers in relation to dimers is significant.

If instead of the complex, nickel chloride and diphenyl sulfoxide are added to the reaction medium, an improvement in the selectivity of the dimers is noticed, but the reaction time is in the range of 30 to 40 minutes, i.e., the reaction proceeds more than 10 or 20 times slower than my catalysate P1M.

On the other hand, if a catalyst consisting of nickel chloride and sulfoxide (without introducing water) was used, it would take from 100 to 200 minutes to obtain only 50% yield of the product. Organic compounds of aluminum are usually used the same as in the known methods. In particular, this is a compound of the general formulas RzAlX, RAlXa, and KsAlHs. Radi.kal R usually alkyl, in particular ethyl, propyl, isopropyl, butyl or isobutyl. Halogen X is usually chlorine and / or bromine.

Although the ratio of organo-aluminum compounds to the nickel complex should be in the range of 3-100, it is preferable that the atomic ratio of aluminum / transition metal in the catalytic system is 6-12, better than 7-9 in the case where the catalyst is obtained in place, i.e. when

simultaneously in the autoclave sulfoxide transition metal kit, solvent, organic compound of aluminum and olef. Again, it is preferable that this ratio exceeds 9 and is in the range of 15-50, preferably 20-30, when the catalyst is prepared in advance, in other words, before its introduction into contact with the dimerized olefin. In these cases, the best selectivity is obtained. For the catalyst obtained in situ, the amount of catalyst may be such that the weight of the transition metal of the complex used is 0.05-5 g of nickel per 1 kg of olefins undergoing dimerization. Excellent results are obtained with 0.1-1 g of nickel per kg of olefin. In the case of a catalyst prepared in advance, this nickel content should be 0.065-1 g per 1 / sg olefinic, preferably 0.001-0.5 a "a 1 kg

olefin.

Dimerization can be carried out at temperatures from -50 ° C to + 80 ° C, but better from -5 ° C to -f 10 ° C. Very good results with transformations of almost 100% are obtained at 0 ° C. Since this temperature is most easily kept constant for the reasons stated above, it is the most preferable temperature for implementing the proposed method.

Solvents suitable for describing dimerization are liquids inert with respect to catalysts, for example, saturated hydrocarbons, if necessary, halogenated, aromatic

hydrocarbons or halogenated aromatic hydrocarbons; aliphatic, aromatic or cyclic ethers that are not reactive with respect to the catalyst. You can, for example, use toluene,

xylene, h.orbenzenes, chloronaphthalenes. Aromatic halogenated solvents are preferred since they result in high reaction rates due to better solubility of the catalytic system. Liquid propylene can also serve as a solvent, just like dimers produced in a reaction. It is recommended to choose a solvent with a rather high boiling point and with a sufficiently low solidification temperature so that the formed dimers can be easily separated after the reaction without the danger of solidification at low temperatures at which dimerization takes place.

It is proposed to use mono- or dihalo-naphthalene and especially α-chloro-naphthalene, the boiling point of which is 259 ° C and the solidification temperature is -20 ° C.

The proposed method has two options

execution. In the first embodiment, the catalyst, solvent, organic aluminum compound and olefin are simultaneously placed in the reactor. According to the second variant, an activated catalyst is prepared in advance and then

its in contact with olefin.

The implementation of the method according to the first option. The experiments were carried out in a 125 ml stainless steel autoclave, equipped with a double jacket for cooling; A certain amount of a nickel sulfoxide complex is introduced into the autoclave under a nitrogen atmosphere. Then, a certain volume of α-chloronaphthalene and a certain amount of ethyl alumi pulpit are passed into it. In an autoclave cooled to 0 ° C, the determined weight of liquid propylene is condensed. The pressure drop of propylene in an autoclave, caused by dimerization, is constant until 90-100% of propylene disappears. At the end of the reaction, the catalyst is deactivated by adding 10 ml of water. The organic phase is recovered and distilled; the craving of the original propylene and the composition of the products formed are determined, which allows one to express the selectivity of dimers with respect to higher oligomers.

The operational method of the second embodiment of the invention allows to obtain conversion and selectivity degrees as good as in the in-situ method; it consists of preparing an activated catalyst prior to its contact with the olefin. This method, which allows continuous operation, has other advantages. Indeed, when a catalyst is prepared in advance, i.e., prior to its being brought into contact with the dimerized olefin, the aluminum / transition metal atomic ratios necessary for obtaining good results are different from those required for obtaining the same results when the catalyst is prepared place

In the first case, the amount of nickel required for the dimerization of olefins is much lower than the amount used in the in situ process. From an economic point of view, this is a big advantage, given the high price of nickel.

The implementation of the method according to the second variant consists in obtaining a catalyst of the type MX2P-K1 (50) pic2Il MX2-P (RiSOR2SOR3), activating it with an organo-aluminum compound so that the elements of aluminum and transition metal are in an atomic ratio equal to or greater than 9, and in use This is a catalyst in operations where it is prepared prior to its use with dimerizing olefins or olefins.

The nickel complex compounds described above are not directly active in this form. In order to impart activity to these complexes, the transition metal (mainly nickel) must be reduced to a lower valence state using an organoaluminum compound. It was noted that the activation of the sulfoxide complex compound by the organoaluminum compound is not instantaneous, but that it can last from 10 to 30 minutes.

So, when working, input to the reactor at the same time. The complex of nickel, the alumina organic compound, the solvent and propylene, the active form of the catalyst is released

only (gradually. The amount of nickel that actually took part in catalysis is much smaller than the amount introduced into the complex compound. In the presence of an active complex compound, the reaction can

Be extremely fast, even stormy, and last for 2-3 minutes. In the first embodiment, the amount of transition metal introduced into the catalyst is chosen such that the organoaluminum compound releases in 2-3 minutes the amount of active complex compound required for the reaction. Since the activation reaction lasts from 10 to 30 minutes, it is easy to see that the amount of transition metal in the catalyst

approximately 5 to 15 times the amount that is actually involved in the reaction.

The duration of the reaction depends in part on the amount of nickel present. but

the amount of nickel should not be too large, since the reaction proceeds rapidly, and a certain amount of nickel may not have time to react. The amount of catalyst may be such that the weight

the transition metal of the complex used was 0.005-1 g in the case of nickel per 1 kg of olefin undergoing dimerization or sodimerization; excellent results are obtained with a content of mp nickel from 0.01 to 0.5 g

per 1 kg of olefin.

To obtain such a catalyst, an inactive complex compound and an organoaluminium halide as a suspension in a solvent must be present.

Oulfoxide complex is insoluble in solvents that are well suited for the day. A homogeneous solution is obtained only after the activation of these complexes by an organoaluminum halide. To obtain an effective catalyst, it is necessary that this activation be carried out in the presence of a protective olefin. It is assumed that this olefn, coordinating with the nickel atom of the active complex compound, stabilizes the latter and prevents its decomposition to metallic npkel.

If propylene dimers are used, it is possible to dispense with the addition of an additional compound that is not related to the reaction and which would have to be subsequently isolated. But since the active complex is poorly soluble in these solvents, a rather large number of them are required. The preferred solvent is

for example, ns 1/3 diameters of propylene and 2/3 of chlorobenzene.

It is necessary that the activation reaction, as well as the preservation of the activated catalyst, be carried out in an inert atmosphere, for example

in argon because catalytic solutions