|Title of Invention||
METHOD OF DEACTIVATION OF THE COMPLEX ORGANOMETALLIC CATALYST OF HOMOGENOUS PROCESS SUCH AS THE ETHYLENE DIMERIZATION OF OLIFOMERIZATION INTO LINEAR ALPHA-OLEFINS AND OF ITS ISOLATION FROM THE REACTION MASS
|Abstract||The present invention relates to a method of the complex organometallic catalyst of homogenous processes, such as the ethylene dimerization or olifomerization into linear alpha olefins and of its isolation from the organic reaction mass, which involves mixing of the reaction mass with a solution of a metal hydroxide in a protic solvent, wherein in order to improve the LAO purity, to simplify technological design and to provide environmental safety of the process, deactivation and isolation of the catalyst from the organic phase is performed in one step.|
Background of the Invention
The invention is related to deactivation of complex organometallic catalyst (COC) of homogeneous processes (e.g., dimerization of ethylene into butene-1 or oligomerization of ethylene into linear alpha-olefins C4-C30 (LAO) ) and its subsequent isolation from the reaction mass.
The invention can be applied in chemical and petrochemical industry, i.e., at plants producing butene-1 or LAO by homogeneous catalytic process using COC. Butene-1, the product of ethylene dimerization, is used as a starting material for synthesis of crystalline polybutene-1, ethylene-butene and propylene-butene plastics (including linear low-density polyethylene) and elastomers, oligobutene oils, butylaromatic hydrocarbons, butadiene, butene alpha-oxide, alpha- and beta-butanols, methylethylketone, dimers and co-dimers of butene-1 with other monomers, and other products. LAO C4-C30, products of ethylene oligomerization, are used as a starting material for production of household detergents, floating reagents, emulsifiers, components of lubricants, coolants and drilling liquids, plasticizers, different types of additives, synthetic low curing oils, polymers and co-polymers, monomers, depressors for petroleum and petroleum products, higher aikylamines, higher aluminumorganic compounds, heat carriers, synthetic fat alcohols and acids, as well as for production of components of different composites based on LAO (C20-C30) - mastics, hermetics, coatings.
In the USA patents 3879485, 3911942, 3969429, British patents 1447811, 1447812, and German patents 2274583, 2462771, a method of ethylene dimerization into butene According to the inventions described in the USSR inventor's certificates 784172, SU 1042701A, 1148149; Italian unaccepted application 24498 A/79; and German patent DE 4338414 CI,, ethylene oligomerization into LAO C4-C30 is performed in organic solvent at 60-80°C and at ethylene pressure 2.0-4.0 MPa. Toluene, benzene or heptane are used as a reaction medium.
According to these documents, ethylene, oligomerization into LAO is performed using COC containing Zr-salt of an organic acid - ClmZr (OCOR) 4-m or ClmZr (OS03R') 4-m
and aluminumorganic compound (AOC) - (C2H5)nAICI3-n, where R and R'- are alkyl,
alkene or phenyl; n smoothly varies from 1 to 2.
In optimum conditions, ethylene di- and oligomerization are homogeneous processes:
no catalyst deposits are formed, and the content of soluble products of ethylene
conversion (in particular polyethylene) is insignificant.
In continuous blending reactors, the reaction mass at the exit of reactor contains a
mixture of a solvent and products of ethylene conversion (butene-1 and LAO for di- and
oligomerization, respectively), with dissolved nonconverted ethylene, catalyst
components, active centers and the products of their spontaneous thermodeactivation.
If di- or oligomerization occurs under the action of living active centers outside the reactor out of control (and, in some , cases, due to throttling), ethylene concentration decreases, temperature drastically increases (or decreases in case*of throttling), and relative concentration of butene-1 or LAO, respectively, increases.
The presence of living active centers, low concentration or absence of ethylene, and relatively high concentration of butene-1 or L.AO in the solution (up to 8 mol/l) cause secondary reactions of butene-1 and LAO, in particular, isomerization of butene-1 into cis- and trans-butenes-2; isomerization of other LAO into olefins with the double bond between intramolecular carbon atoms; concurrent di-, tri- and oligomerization of butene-1 or LAO, their conversion into isoolefins.
Duration of contact of LAO-containing oligomerizate with the ,lliving" catalyst in the absence of ethylene appeared to be the most crucial factor. Table 1 shows that, in the absence of ethylene, LAO R-CH=CH2 oligomerizes under the action of catalyst to form isoolefins. This is confirmed by a decrease in the content of double bonds in the reaction mass and by formation of oily oligomers with the average molecular weight of 350-800. Degree of conversion for olefins with vinyl double bonds increased with increasing duration of LAO contact with the "living" catalyst.
The catalysts contain AOC (C2H5)nAiCI3-n which are strong Lewis acids. In the systems under consideration, cationic active centers easily form on the AOC. These active centers are responsible for isomerisation, di-, tri-t and oligomerization of LAO, as well as alkylation of the aromatic solvent.
Diffusion of water and alcohol traces into the reaction mass containing LAO and the "living" catalyst causes a considerable heating of the reaction mass and drastic
acceleration of the cationic processes involving LAO. In steady-state conditions, the cationic reactions and heating of the reaction mass occur in a frontal mode.
All the above-mentioned secondary reactions of butene-1 and LAO proceed at high speed.
Apparatuses for ethylene throttling, collectors of the reaction mass, and columns for isolation of narrow fractions of butene-1 and LAO from the reaction mass provide favorable conditions for secondary reactions of butene-1 and LAO under the action of the "living" catalyst.
Butene-1 or LAO secondary reactions are accompanied by consumption of olefins with vinyl double bonds, and by contamination of butene-1 and LAO with the products of their conversion. This decreases selectivity of the catalyst and the process.
Evidently, secondary reactions of butene-1 or LAO are undesirable. To prevent the secondary reactions, it is necessary to deactivate the "living" catalyst immediately after its removal from the reactor.
Methods of deactivation of the catalyst containing ClmZr(OCOisoC3H7)4-m and (C2H5)nAICI3-n by the addition of stoichiometric amount of carboxylic acid are know (US patent 4 486 615, German patent 4 338 415).
The former method (USA patent 4 486 615) is characterized by formation of considerable amount of HCI, which causes intense corrosion of the equipment. Besides, a considerable amount of chemically contaminated waste water forms during isolation of the deactivated catalyst by counterflow water flushing of the oligomerizate.
Zr- and Al- containing products of catalyst deactivation by carboxylic acids according to the latter method (German patent 4 338 415) are isolated from, the reaction mass by passing it through the layer of an adsorbent (silicagel, kaolin, aluminum oxides, zirconium dioxides, sawdust).
In this case, deactivation of the catalyst by alkohols results in formation of considerable amount of HCI, which also causes corrosion of the equipment. Moreover, the process is accompanied by the formation of lange amount of waste water during regeneration of the adsorbent. Regeneration of the adsorbent requires complicated technological
design because it is performed at 60°C, which restricts the number of appropriate materials for adsorbers.
Methods, in which water-alkali or water-ammonia solutions are used as deactivating systems are similar to the suggested one: (1) Pheldblum V.Sh. Dimerization and disproportionatJon of olefins. Moscow: Khimiya, 1978; (2) Application N 3-220135 of 24.01.1990. Japan; (3) R.Zh.Khim, 1993. 15AI7P. These solutions are also used for isolation of the deactivated catalyst from the oligomerizate. Water-alkali or water-ammonia isolation of the worked-out deactivated catalyst is followed by additional flushing of the oligomerizate with demineralized water.
Alkali and ammonia are intended mainly for neutralization of HCI formed during hydrolysis of Cl-containing products of COC reactions. This method is also accompanied by the formation of considerable amount of chemically contaminated water waste.
On the other hand, slow and inefficient mixing of water- and oleophases in stirrer-equipped apparatuses or in widespread orifice mixers causes formation of cationic active centers, cationic oligomerization of LAO, and toluene alkylation with linear alpha-olefins. In all known methods, deactivation and isolation of the deactivated catalyst is performed in two stages before separation of the oligomerizate into narrow fractions. The aim of this invention is to increase the purity of LAO, that is, to increase the selectivity of the catalyst and the processes of dimerization and oligomerization of ethylene. Another purpose of the invention is to simplify the stage of deactivation and isolation of the catalyst and to eliminate water wastes, thus providing ecological safety.
General Description of the Invention
According to the developed method, THESE PURPOSES CAN BE ACHIEVED BY mixing of the reaction mass with a solution of metal hydroxide in a protic solvent and isolation of the deactivated catalyst from the organic phase in one stage at 60-100°C and ethylene pressure of 2-4 MPa.
This temperature range is chosen because the deactivation of "living" catalyst, as well as di- and oligomerization proceed under the similar conditions.
According to the invention, deactivation of the catalyst by a solution of metal hydroxide in protic solvent is weakly sensitive to temperature: deactivation rate and selectivity with respect to U\0 are almost independent from temperature. However, an elevated
ethylene pressure is required in oder to improve the selectivity of the process with respect to LAO.
The chosen ethylene pressure range (2-4 MPa) ensures high selectivity and high rate of COC deactivation.
Deactivation rate and selectivity with respect to LAO are strongly dependent on the
efficiency of mixing. Therefore, meanical mixing is combined with ultrasonic treatment
of the mixture of metal-hydroxide solution with organic phase in the protic solvent using
a three-dimensional grid with a magnetostrictor placed in the mixer and connected to a
UZG-2.5 ultrasound generator. The ultrasonic treatment ensures sharp increase in
dispersion of liquid droplets up to complete homogenization of the mixture
(N.N. Kruglitzkii et al, "Ultrasound in chemical technology", Kiev. UKRNI1TY, 1970;
Collection of papers 'Thermal and salt stability of dispersed systems", Kiev. Naukova
Dumka, 1971). More efficient mixing and high stability of the resultant dispersed mixture
of oligomerizate and water-alkali solution provide higher rate of catalyst deactivation
and improved selectivity of the process.
The protic solvent is subsequently isolated from the reaction mass by rectification and
adsorptive purification, while deactivated catalyst remains in the organic phase. The
isolated protic solvent is fed back for preparation of the alkali solution. This prevents
waste formation, thus providing ecological safety of the process.
Water, alcohol or ammonia are usually used as the protic solvent for preparation of the
alkali solutions for COC deactivation.
Alkali content varies from 1 to 40 wt %, preferably, from 5 to 10 wt %.
Hydroxides chosen from a group of lithium, sodium, potassium, beryllium, magnesium,
calcium, ammonia or aluminum hydroxides are used as alkalies. The latter is water
insoluble, and, therefore, is used in the form of suspension.
In spite of great efforts to study reactions between the COC components during
ethylene di- or oligomerization and in model conditions, the composition of the products
is still unknown. Thus, mechanism of catalyst deactivation cannot be exactly described.
The available data allow us to suggest tentative mechanism of the process.
Brief Description of the Drawings
Figure 1-3 show schematic, diagrams of the process stages of .deactivation of "living", catalyst and isolation of the deactivated catalyst from the oligomerizate, which are illustrated below:
Example 1, see Fig. 1:
1 - a unit of preparation of the alkali solution
2, 3 - a unit of water-alkali COC deactivation, where 2 is a blender-deactivator and 3a
4, 5 - a unit of water flushing of the oligomerizate (4 - blender-scrubber; 5 - settling
6 - a unit of azeotropic or fixed bed drying of the oligomerizate
7 - a unit of atmospheric-vacuum separation of the oligomerizate into components and narrow fractions
8 - a unit of waste water neutralization by carbonic acid
9 - sedimentation or filtering centrifuge;
10, 11 -a unit of the slime procossing, where 10 -spray flame dryer, 11 - multicyclone; 12 - a unit of isolation of hydrocarbons dissolved in waste water.
Example 2, see Fig. 2;
1 - a unit of preparation of the alkali solution
2, 3 - a unit of water-alkali COC deactivation equipped with a mixer (3)
4 - a unit of the solvent isolation
5 - unit of isolation of deactivated COC sedimentation centrifuge or pressure filter
6 - a unit of high-temperature oxidative mineralization (spray flame dryer)
7 - cyclone-dust extractor
8 - a unit of oleophase separation into LAO narrow fraction.
Example 3, see Fig. 3:
1 - a unit of preparation of the alkaline solution
2, 3 - a unit of COC deactivation equipped with a mixer (3)
4 - a unit of isolation of the protic solvent
5 - a unit of oligomerizate separation into narrow LAO fractions;
6 - a unit of extractive separation of waxy LAO and the products of COC deactivation
7 - sedimentation centrifuge or pressure filter;
8 - a unit of isolation of purified waxy LAO; 9 - spray flame dryer; 10 - cyclone-dust extractor;
The diagrams show directions of the main material flows.
Comparison of these diagrams shows that the suggested method is characterized by
less complicated technological design and is free of waste water. It requires 10 times
less amount of alkalihydroxide solutions for deactivation. Furthermore, no need in
demineralized water (for oligomerizate flushing) and gaseous carbonic acid for
neutralization of wastes. These are very important advantages of the method.
The method under patenting can be used in homogeneous di- or oligomenzat.on,
metathesis telomerization, hydrogenation, alkylation using soluble COC conta.n.ng
titanium zirconium, hafnium, nickel, molibdenum, tungsten and other transition metals.
The active center of ethylene oligomerization is known to involve Zr-organic compound, which contains sigma Zr-carbon bond, for example,->Zr-CH2-CH3. Alcohol, water, or ammonia-alkali deactivation of "living" COC is accompanied by alcoholysis or hydrolysis of these bonds:
~>Zr-CH2-CH3 + H20 -— > ->Zr-OH + C2H6
Since there are only few active centers in COC, the deactivating agent will be consumed predominantly in reactions with COC components. Let us consider a probale mechanism of water-alkali deactivation of COC which involves Zr (OCOisoC3H7)4 and (C2H5)1.5AICI1.5 (Al/Zr = 13). Taking into account the results of model experiments on hydrolysis of the components in toluene, it can be tentatively described as follows:
Zr (OCOisoC3H7) 4 + 4NaOH — > Zr(OH)4 + 4Na0C0isoC3H7
13(C2H5)1.5AICI1.5+ 19.5H20 —> 19.5C2H6 + 13(H0)1.5AICI1.5
13(H0)1.5AICI1.5 + 19.5NaOH ---> 13AI(OH)3 + 19.SNaCI
13AI(OH)3 + 13NaOH —> 13NaAI02 + 26H20
By summarizing left and right parts of these equations, we obtain the following overall reaction:
Zr(OCOisoC3H7)4 + 13(C2H5)1.5AICI1.5+ 36.5NaOH —>
Zr(OH)4 + 4NaOCOisoC3H7 + 19.5C2H6 + 19.5NaCI +
+ 13NaAI02 + 6.5H20
This equation shows stoichiometry of the reactions occuring in the deactivator. Sodium hydroxide is the main deactivating agent. To ensure complete deactivation, it is reasonable to use a 10-20 % over-stoichiometric amount of sodiurrvhydroxide. Water is not consumed during the COC deactivation; therefore, minimum amount of water is required to dissolve sodium hydroxide. This allows to reduce engergy consumption for desiccation of the reaction mass.
After isolation of the protic solvent, the oleophase contains hydrocarbon-insoluble sodium hydroxide, sodium chloride, sodium aluminate, sodium zirconate, aluminum and zirconium hydroxychlorides, aluminum and zirconium hydroxides, alumina, zirconia, and sodium isobutyrate in the form of highly dispersed suspension. They can be isolated either by filtration and inertial-gravity sedimentation before separation of the oleophase into narrow fractions or after its separation by atmospheric-vacuum distillation in several columns at 60-300X.
Studies under model and operating conditions show that LAO are stable in a range of 60-300cC even in the presence of products of alcohol, water or ammonia-alkali COC deactivation. This provides the background of our approach.
During atmospheric-vacuum distillation of the oleophase, concentration of the deactivated catalyst (in the form of suspension) gradually increases by a factor of 10-to-20. After completion of distillation, the deactivated catalyst together with polyethylene traces and waxy LAO get into the bottoms.
According to the invention, the products of deactivation of the worked-out catalyst are separated by extraction. Waxy olefins from the bottoms are extracted by hydrocarbon low-boiling solvent choosen from the group: hexane, heptane, gasoline, benzene, toluene, butene-1, hexene-1, octene-1, while the products of the catalyst deactivation are flushed with the same solvent and delivered in the form of suspension into settling tank, filter or centrifuge, where they are separated from the hydrocarbon solvent.
For economical reasons, the solvent used or formed during oligomerization can be used as the extractant. Among the abovementioned solvents, toluene exhibits the best extracting ability with respect to waxy LAO.
Then, the isolated insoluble products of catalyst deactivation are calcined (high-temperature oxidative mineralization) in a spray (flame) drying chamber. Calcining is followed by recovery of sodium, aluminum, and zirconium. In particular, recovery of Zr by a metallurgical technique is reasonable to perform when its content in a dry slime is above 3 wt %, as in the described method of catalyst deactivation. _
The extract together with flushing hydrocarbon solution are subjected to distillation in order to isolate waxy LAO. The hydrocarbon solvent is recycled for extraction of waxy LAO from the bottoms, while waxy LAO are fed for utilization or storage.
1.1 Ethylene oligomerization was performed on Zr(OCOisoC3H7)4 (0.382 mmol) (0.0348 g of Zr) + (C2H5)1.5AICI1.5 (Al/Zr = 13) system in toluene (0.25 I) at 80°C and ethylene pressure of 2.0 MPa for 60 min. 187.5 g of ethylene was consumed and about 250 ml of LAO was formed.
1.2. The catalyst deactivation in the oligomerizate (about 500 ml) was performed with water-alkali solution containing 15 ml of water and 3.4 g of sodium hydroxide (18.5 wt %) in the reactor, under the above-mentioned conditions, with intense stirring of the oligomerizate and deactivating solution for 20 min, using the shielded electromagnetic stirrer and the ultrasonic generator in the bottom of the reactor. 20 minutes after loading of alkali water solution into reactor, the oligomerizate was sampled for various analyses. The reaction mass cooled to 20-25°C, and ethylene throttling was carried out. During throttling, almost total amount of the formed butene-1 was removed from the reactor together with ethylene. Then the reaction mass was discharged from the reactor. No stratification of the reaction mass into oleo- and water phases was observed.
1.3. The obtained reaction mass (about 500 ml) containing the products of the catalyst deactivation was charged into the still of the highly efficient column for the atmospheric-vacuum distillation of the oligomerizate. Initially, azeotropic desiccation of the oligomerizate was performed at 60-700°C. 14.2 ml of water was taken from the Florentine, which is about 94.6 wt % of starting amount of water loaded in the reactor.
1.4. After drying, hexene-1, toluene, octene-1, decene-1 and C12-C18 LAO-fractions
were isolated from the oligomerizate. After completion of distillation, 30 g of hot
milky-white homogeneous bottoms was unloaded from the column still. The
isolated bottoms contained waxy LAO, Zr-,, Al-containing compounds, sooium
chloride and sodium -i-sobutyrate.
1.5. The bottoms (about 30 g) was charged in the glass reactor with thermostating jacket equipped with spiral-shaped power-driven stirrer. 280 ml of toluene was charged there. After mixing the mass at 80°C for 20 minutes, a solution of waxy LAO and suspension of the catalyst deactivation products yielded. A deposit after settling was separated from the waxy LAO solution by decanting. Then 100 ml of fresh toluene was added to the deposit. The resulting suspension was stirred for 20 minutes under the same conditions. The deposit was separated from the flushing solution on the centrifuge, the centrifugate obtained was united with the LAO toluene solution separated formerly.
1.6. The products of the catalyst deactivation were dried in a desiccator in air media at 300°C for 60 minutes. 3.82 g of the precipitate was obtained. To perform Zr analysis, 0.0111 g of the precipitate was sampled and dissolved in 3 ml of the standard analytical solution. Calorimetry method showed that 0.0111 g of the precipitate contain 95-10'6 of Zr, that is, 3.82 g of the precipitate contain 0.0327 g of Zr (94 mas% with respect to the stalling Zr(0.0348 g) which was loaded in the reactor as Zr(OCOisoC3H7)^). Zr Loss is 6 mas%, due to high adhesion of Zr hydroxide, which sticks to the reactors, flasks and pipettes walls.
Analysis of Al and CI show that the precipitate contains 0.13 g of Al (97.2 mas% with respect to the starting Al (0.1342 g) which was introduced in the reactor as (CiHsJi.sAlClj.s) and 0.253 g of chlorine (95.6 mas% with respect to the starting chlorine (0.266 g) loaded in the reactor as (C2HS),.5A1CI,.5.
1.7. The united solution of waxy LAO in toluene (about 370 ml) was loaded in the still of atmospheric-vacuum rectification column, and toluene was almost completely distilled off at 111°C and ambient pressure. The rest of toluene from waxy olefins was distilled off in vacuum, using a trap cooled with liquid nitrogen. Totally, 361 ml (95%) of toluene was distilled off. 24.1 g of waxy LAO was unloaded from the still (about 12.85 mass% with respect to the ethylene consumed during oligomerization).
1.8. Table 2 presents the LAO group composition, which were isolated from oligomerizate obtained while deactivating the catalyst under ultrasound irradiation of the mixed liquids and in reference conditions (without ultrasound irradiation). The Table shows that ultrasound irradiation of the mixed oligomerizate and sodium hydroxide water solution increases the catalyst and the process selectivity. This is confirmed by reduction of olefins with vinylene and vinylidene double bonds content in LAO fractions, and by complete absence of alkylation.
2.1. Ethylene dimerization was performed on Ti(OnC.,H9).rAl(C2Hs)3 system in diethyl ether. 0.2 1 of diethyl ether, 0.1875 g (0.55 inmol) of titanium tetrabutoxide and 3.11 g (27.2S mmol) of triethylaluminum (Al/Ti= 49.6) were loaded in the reactor of 1.1. 1 volume. 435 g (7.76S mol) of ethylene was consumed during 250 minutes at 40°C and ethylene pressure of 8.0 atm. Average speed of dimerization was 8.5 g of C2H./l-min (0.52 kg of C4Hs/l hour). Butene-1 yield is 2.32 kg/g of Ti(OnC4H9)j or 14100 mol of butene-1 with respect to a mol of Ti(OnC4H9)4. There were no cis- and trans-butenes-2, as well as polyethylene, in the products. In addition to butene-1. 9.1 g of hexenes and octenes (2.1 mas% with respect to butene-1) was formed.
2.2 Deactivation of the catalyst was performed in the reaction mass (about 900 ml) with water-alkali solution containing 15 ml of water and 0.15 g (3.75 mmol) of sodium hydroxide (0.99 mas% with respect to water), in the reactor under the same conditions, with intense stirring of the reaction mass with the shielded electromagnetic stirrer and the equipment for irradiation of the resulting mixture with ultrasound, installed in the bottom of the reactor, during 20 minutes. 20 minutes after loading of alkali water solution into the reactor, gas phase was sampled for chromatography.
2.3. The reaction mass containing diethyl ether, butene-1, hexenes and octenes, water and
products of the catalyst decomposition, was transferred by the ethylene pressure, available in the
reactor, into the still of metallic reaction column equipped with dephlegmator and florentine vessel.
First, ethylene throttling was carried out at 20-30°C, then - azeotropic desiccation of the reaction
mass at 0-5°C. 11.0 ml of water was removed from the Florentine, that is 73.3 mas% with respect
to the loaded water.
2.4. Then butene-1, diethyl ether and hexenes were isolated. After distillation was
completed, bottoms containing octenes, a small amount of the unknown resin-like product and
products of the catalyst deactivation (supposedly, Ti, Al, and Na hydroxides, as well as sodium
aluminates) were left in the column still.
2.5. 100 nil of n-heptane wns charged in the column slill. After the mixture was being
mixed at 200° C for 20 minutes with a flexible stirrer which was introduced in the slill through the
side sleeve, a solution of resin-like products and a suspension of products of the catalyst
deactivation were formed. The deposit and the solution were unloaded into the glass. The
hydrocarbon layer was separated by decanting, and the precipitate was flushed with 40 mi of n-
heptane. The precipitate was separated from the flushing solution on the centrifuge, the centrifugate
was joined to the foimerly separated n-heptane solution.
2.6. The products of the catalyst deactivation were dried and calcined in a muffle at 600°C in air during 60 minutes. 1.53 g of the deposit was obtained, which contained 0.0246 g of Ti (92.8 mas% with respect to Ti loaded as TiCOnC^H.)^), and 0.70 g of Al (95.1 mas% with respect to Al loaded in the reactor as AJ(C>Hs)3).
2.7. The united n-heptane solution (about 130 ml) was loaded in the still of off at 98° and ambient pressure. The rest of n-heptane was distilled off in vacuum using a trap cooled with liquid nitrogen. Totally, 128 ml (91.4%) of n-heptane was distilled off. 1.1 g of hot oily substance was removed from the still (0.25 mas% with respect to the consumed ethylene).
Example 3 - 14:
The reagents and ethylene to LAO oligomerization conditions were the same as in Example 1. The catalyst in the oligomerizate was deactivated with water, alcohol, and ammonia alkali solutions just in the reactor, with mechanical stirring of the mixing solutions, with additional solution homogenization using ultrasound similar to Example 1.
In Examples 3-14 the solvent for alkali, origin and concentration of alkali were changed (Table 3). The subsequent steps of the reaction mass separation into fractions, isolation and treatment of products of the catalyst (Zr(OCOisoC3H7)4-(C2H5)i.5AlCli.5 deactivation were similar to ones in Example 1. Table 3 presents a degree of Zr, Al and CI isolation with respect to loading of these elements as the catalyst components. Though more water was expended, magnesium, calcium and beryllium hydroxides were not totally dissolved, and Al hydroxide was completely
Influence of duration of LAO contacting with the "living" catalyst Zr(OCOisoC3H7)4
-(C2H5),3AI2CI3 at ambient pressure after ethylene throttling on the content and
composition of olefins in the reaction mass (oligomerizate).
Temperature +80°C, Zr(OCOisoC3H7)4 -1.17 mmol; Al/Zr = 17;
Ethylene pressure 2.2 --> 0.1 MPa; Olefins concentration in Oligomerizate - about
1. US patent 3879485
2. US patent 3911942
3. US patent 3969429
4. British patent 1447811
5. British patent 1447812
6. German patent 2274583
7. German patent 2462771
8. USSR author's certificate 1042701 of 19.06.1978 Byull. Izobret. 1983, N35
9. Italian application 24498.79
10. German patent 433 8414 of 10.11.1993
11. German Patent 433 8416 of 10.11.1993
12. US Patent 4486615
13. German patent 4338415 of 10.11.1993
14. Japan application N 3-220135 of 24.01.1990, RZhKhim 1993 15A17
1. Method of deactivation of the complex organometallic catalyst of homogeneous processes, such as the ethylene dimerization or oligomerization into linear alpha-olefins, and of its isolation from the organic reaction mass, which involves mixing of the reaction mass with a solution of a metal hydroxide in a protic solvent, wherein in order to improve the LAO purity, to simplify technological design and to provide enviromnental safety of the process, deactivation and isolation of the catalyst from the organic phase is performed in one step.
2. Method of claim 1, wherein mechanical mixing of the organic phase with the metal hydroxide solution in the protic solvent is enhanced by irradiation of the mixture with ultrasound.
3. Method of claims 1 or 2, wherein the protic solvent is isolated from the reaction mass by distillation or by adsorption purification and the deactivated catalyst remains in the organic phase.
4. Method of claims 1-3, wherein the deactivated catalyst from the organic phase is isolated from the bottoms of the last separation column, which contain both the deactivated catalyst and waxy linear alpha-olefins, after the reaction mass has been separated into fractions.
5. Method of claims 1-4, wherein isolation of the deactivated catalyst from the bottoms involves extraction of waxy LAO with the hydrocarbon solvent, inertial-gravitation precipitation of the deactivated catalyst from the hydrocarbon extract and the subsequent high temperature oxidative mineralization of the isolated deactivated catalyst.
6. Method of claims 1-5, wherein a hydrocarbon solvent from the group including isopentane, hexane, heptane, gasoline, benzene, toluene, butene-1, hexene-1,
and octene-1 is used as a hydrocarbon solvent for extraction of waxy linear alpha olefins from the bottoms of the last separation column, which contain the deactivated catalyst and waxy linear alpha olefins, after the reaction mass has been separated into fractions.
7. Method of claims 1-6, wherein solutions containing 1-40 mass % of metal
hydroxide are used for the catalyst deactivation.
8. Method of claims 1-7, wherein metal hydroxides from the group including lithium
hydroxide, sodium hydroxide potassium hydroxide, beryllium hydroxide,
magnesium hydroxide, calcium hydroxide, aluminum hydroxide and ammonium
hydroxide are used as a metal hydroxide for the catalyst deactivation.
9. Method of claims 1-8, wherein deactivation of the catalyst is carried out at
temperatures of 60 to 80°C and pressure of 2.0 to 4.0 MPa.
10. Method of claims 1 to 9, wherein waxy LAOs are isolated by distillation of the
hydrocarbon solvent from the extract which contains a hydrocarbon solvent and
11. Method of claims 1 to 10, wherein the deactivated catalyst is separated from the
organic phase prior to the separation of LAO into fractions.
The invention can be applied in chemical and petrochemical industry, at plants
producing butene-1, finear alpha olefins C4-C30 (LAO) and other products soluble in
the reaction media, using complex organometallic catalysts COC.
PURPOSE OF THE INVENTION - to increase LAO purity, to simplify technological
design and to provide environmental safety.
THE METHOD INVOLVES
- deactivation of COC of the ethylene to LAO oligomerization using mechanical mixing of the reaction mass exiting from the reactor and containing the solvent LAO and the "living11 catalyst with a solution of the metal hydroxide in a protic solvent such as water, alcohol, or ammonia at 60-80°C and ethylene pressure of 2-4 MPa, upon addition enhancing of irradiation of ths mixture with ultrasound.
- isolation of the protic solvent from the reaction mass by distillation and adsorptive purification, and its using the recycle;
- subsequent separation of the reaction mass into fractions, and isolation of the deactivated catalyst together with waxy LAO as bottoms from the last separation colunm as the bottoms;
- isolation of the deactivated catalyst from the bottoms by extraction of waxy LAO with the hydrocarbon solvent, inertial-gravitation precipitation of the.deactivated catalyst from the hydrocarbon extract and the subsequent high temperature oxidative mineralization of the isolated.deactivated catalyst.
- isalation of waxy LAO from the extract, which contains a hydrocarbon solvent and
waxy LAO, by distillation the hydrocarbon solvent which is returned to the process.
To deactivate the catalyst, solutions containing 1 - 40 mas% of a metal hydroxide are
used. Metal hydroxide from the group including lithium hydroxide, sodium hydroxide,
potassium, hydroxide, beryllium hydroxide, magnesium hydroxide, calcium hydroxide,
aluminum hydroxide, and ammonium hydroxide are used.
A hydrocarbon solvent from the group including isopentane, hexane, heptane, gasoline, benzene, toluene, butene-1, hexene-1, and octene-1 is used for extraction of waxy LAO from the bottoms.
|Indian Patent Application Number||344/MAS/1998|
|PG Journal Number||37/2007|
|Date of Filing||20-Feb-1998|
|Name of Patentee||LINDE AKTIENGESELLSCHAFT|
|Applicant Address||ABRAHAM LINCOLN STRASSE 21,D-65189 WIESBADEN.|
|PCT International Classification Number||C07C02/22|
|PCT International Application Number||N/A|
|PCT International Filing date|