FI92327C - A process for preparing an olefin polymerization catalyst having uniform particle sizes - Google Patents

Description

92327

The invention relates to a process for preparing a particulate procatalyst composition for olefin polymerization by reacting support particles formed from a MgCl 2 -C 2 H 5 OH complex with TiCl 4.

10 For the polymerization of olefins, Ziegler

The Natta catalyst system, which consists of the so-called procatalyst and cocatalyst. The procatalyst is based on a transition metal compound of Groups IVA-VIII (Hubbard) of the Periodic Table of the Elements and the cocatalyst is based on an organometallic compound of a metal of Groups IA to III (A) (Hubbard) of the Periodic Table of the Elements. The catalyst system may include a mytts support on which the transition metal compound is deposited and electron donor compounds that enhance and modify the catalytic properties.

In the preparation of Ziegler-Natta procatalysts for the polymerization of olefins, in particular propylene, the support particles forming solid magnesium chloride and ethanol are reacted with titanium tetrachloride. The result is an amorphous magnesium chloride with a strongly modified crystal structure, i.e. in use, which is able to coordinate with titanium tetrachloride. The titanium tetrachloride combined with the amorphous magnesium chloride then forms the active centers of the catalyst. Hydrogen chloride and ethoxytitanium trichloride (1, 2) are formed as a by-product of the TamSn process:

MgCl2 * EtOH + TiCl4 = MgCl2 * + TiCl3-OEt + HCl (1) 35 lOMgClj · + TiCl4 = 10MgCl * TiCl4 (2)

The procatalyst prepared in this way under laboratory conditions has obtained a high activity polyolefin, 2 92327, the particle size, particle size distribution and other properties of which have been satisfactory.

However, in the transition from laboratory-scale to larger-scale production, it has been found that the particle size distribution of the polymer product is anything but satisfactory. Namely, the product contains very large quantities of a fine-sized substance, i.e. a material with a diameter of less than 10 one millimeter, compared to a product made in a laboratory procatalyst. This can be seen e.g. Figure 1, in which the proportion of fine-grained material increases manyfold from a laboratory-prepared procatalyst to a pilot-sized procatalyst. Since the polymerization of tiprocatalysts is dominated by the so-called The "replication" phenomenon, i.e. the morphology of the polymer particles formed, corresponds to the morphology of the procatalyst used in the preparation of the polymer, it was obviously assumed that the formation of fines in the polymer was due to the decomposition of the procatalyst particles for polymerization in pilot scale preparation 20.

In the preparation of procatalysts, it was found, in excess, that there was a clear correlation between the maximum value of the hydrogen chloride release rate formed in reaction (1) and the proportion of polymer fines. This correlation is shown in Figure 2. It can be seen from the figure that the proportion of finely divided polymer increases as the instantaneous hydrogen chloride discharge intensifies. In the same context, it was found that the hydrogen chloride discharge intensified with increasing ethanol content of the magnesium chloride-ethanol complex. This gave rise to the idea that the scale-up problem of catalyst production associated with the formation of a fine polymer would be due to the excessive release of hydrogen chloride.

35 For this reason, a system with a drop of magnesium chloride-ethanol complex, titanium tetrachloride and hydrogen chloride from their silent reaction, a system with a drop of titanium tetrachloride alone and 3,932327 hydrochloric acid, and a system with a drop of magnesium dichloride and a system of magnesium dichloride were compared.

When the first system was heated from a temperature of 5 to 20 ° C to a temperature of + 110 ° C, a strong discharge of hydrogen chloride occurred at +10 and + 20 ° C, the formation of which was normalized to the normal consumption of dissolved gas in lamp spaces above 40 ° C. This is apparent from Figures 3 and 4, of which Figure 3 shows the amount of hydrogen chloride released from system 10 (expressed as NaOH consumption) as a function of system lamp state and time, and Figure 4 shows the rate of hydrogen chloride release from the system as a function of temperature.

15 In the second and third mentioned systems, which lacked the magnesium chloride-ethanol complex, no strong hydrogen chloride discharge of the above-mentioned type was observed.

Preliminary experiments have thus shown that the formation of 20 harmful fine-grained polyolefins using a pilot-scale procatalyst obtained from the silent reaction of MgCl2-C2H5OH complex particles and TiCl4 is essentially due to the fact that (1) the reaction shown produces at once 25 so much hydrogen chloride that it immediately gasifies and confines the carrier particles to a finely divided material which is then repeated in the resulting polyolefin.

It is an object of the invention to provide a process for preparing a particulate procatalyst composition for olefin polymerization which results in a useful procatalyst composition having a usable particle size distribution substantially free of fines. In addition, the particles must be usable in shape, chemical composition, activity and stereospecificity. The invention also seeks to ensure that the polymer prepared with the procatalyst composition does not contain a substantially finely divided substance. At the same time, of course, 4,932,327 polyolefins having a useful particle form, isotacticity and crystallinity, melt viscosity and bulk density are sought.

A new process for the preparation of a waste molar pro-catalyst composite for olefin polymerization is now fastened to this process, which is mainly characterized by what is stated in the characterizing part of claim 1. Thus, it has been realized that the carrier particles in the MgCl 2 -C 2 H 5 OH-10 complex are decomposed mainly due to the chlorine-hydrogen discharge when activated with titanium tetrachloride. (It has previously been thought that the decomposition is due, among other things, to the mechanical stress caused by the mixing.) This phenomenon occurs especially when the preparation of the procatalyst takes place in a larger, eslm. pllot-mlttakaavassa. Due to the disintegration of the carrier particles, the carrier and thus the entire procatalyst composition contains a large amount of finely divided material. The particle size distribution of the procatalyst composition is then repeated in the polymerization with a particle size distribution of the polymer product, with the polymer also having a high proportion of finely divided material.

The foregoing realization that a large proportion of the finely divided material in the polymer product is due to the strongly discharged hydrogen chloride gas in the procatalyst-25 synthesis allows a process for preparing a procatalyst composition that results in a very waxy finely divided procatalyst composite. In the process, the carrier particles are kept intact during the reaction by equalizing the release of hydrogen chloride from the reaction or the reaction mixture at a molar rate not exceeding five times the average molar rate of release. Looking again at Figures 3 and 4, it can be seen that without the specific measures of the invention, the maximum rate of hydrogen chloride discharge increases to a value corresponding to a NaOH consumption of about 16 ml / ° C, with an average discharge rate of the order of about 2 ml / ° C. NaOH consumption. In this experiment, the hydrogen chloride discharge of a sysli 5 92327 theme with a complex! contained 3 molecules of ethanol per molecule of magnesium chloride, so that the hydrogen chloride discharge rate peak was about eight times as high as the average release rate. It should be noted that with a complex content of 4.5 moles of ethanol per mole of magnesium chloride, the maximum discharge corresponded to a NaOH consumption of up to 90 ml / ° C with an average volumetric hydrogen release rate of the order of 1-5 ml / eC NaOH consumption. that is, the discharge peak was more than 20 times the mean release rate.

It can be seen from Figure 4 that the release of hydrogen chloride should be limited so that no more than about 5%, preferably up to about 2% of the total amount of hydrogen chloride released in the reaction stoichiometrically is released per minute. This is another way to quantify the inhibition of strong hydrogen chloride release.

Within certain limits, it is preferable to minimize the instantaneous discharge of hydrogen chloride in order to prevent breakdown of the carrier particles as effectively as possible. According to one embodiment of the invention, the release of hydrogen chloride from the support particles and the titanium tetrachloride in the silent reaction in the reaction or reaction mixture is equalized to a molar rate not exceeding three, preferably twice, the average molar rate of release.

The invention is based on the idea that the strain particles reacting with TiCl4 are kept intact to prevent the sudden discharge of hydrogen chloride formed during their activation. One-way damping, i.e., balancing the release of hydrogen chloride, can be accomplished by any suitable chemical and / or physical means. The prevention of sudden gas discharges is a general measure in technical chemistry and the present invention is not limited to specific embodiments of this general measure, but specifically to the use of a measure to prevent the formation of finely divided material in a procatalyst composition and olefin polymers.

The release of hydrogen chloride displaced in the reaction can be equalized by selecting the correct order of addition of the reagents and the rate of addition. The order of addition is preferably such that TiCl 4 is added by the carrier particles, and not vice versa. In addition, the carrier particles are preferably suspended in an inert reaction medium. According to one embodiment of the invention, TiCl 4 is added to the liquid suspension of MgCl 2 -C 2 H 5 OH complex carrier particles in a controlled manner over a period of 0.5 to 3.0 hours, preferably about 1.0 hour. Hydrocarbons inert to the reagents are generally used as the liquid suspension starting material, the amount of which can be obtained to reduce the tendency to discharge hydrogen chloride.

Controlled, slow addition of TiCl 4 reduces the risk of hydrogen chloride evolution by slower production of hydrogen chloride (see Reaction Compounds (1)), which thus has time to diffuse out of the carrier particles before hydrogenation leading to gas evolution occurs in their pores. In addition, at least some of the intermediate reaction steps between the MgCl 2 -C 2 H 5 OH complex and TiCl 4 are apparently exothermic, with the slow addition of TiCl 4 allowing lanund to move away from the carrier particles and thus preventing the carrier particles from warming locally over the hydrogen chloride discharge amp.

It is clear from the foregoing that TiCl4 should preferably be added in such a low lamp state that no strong reaction and discharge of hydrogen chloride occurs. According to an embodiment, TiCl 4 is added in the lamp room -30 to -10 ° C and preferably in the lamp room -25 to -15 ° C.

Due to the thermodynamic and / or physical equilibrium systems in the pores of the carrier particles and in the TiCl4 solution, hydrogen chloride is released over a long period of time into the addition of TiCl4. It is preferred to raise the lamp space during the addition of TiCl 4 and / or its fraction at a controlled slow rate of about 11-2032 C / h, more preferably at a rate of about 5-15 ° C / h. It is advisable to continue the slow raising of the lamp state up to the lamp state of + 40 ° C, and especially of its fraction when any necessary internal donor 5 has been added to the reaction mixture of the carrier particles and TiCl 4.

The release of the hydrogen chloride formed in the reaction can also be offset by vigorous mixing of the carrier particles during the silent reaction of the carrier particles and TiCl4. Although the strength of the mixture depends on many factors, such as other means of compensating for the release of hydrogen chloride, it can be said that the amount of mixture in the present invention exceeds conventional mixing values and causes substantial equalization to the release of hydrogen chloride. Since in the preparation of procatalyst compositions, 15 mixtures have often been accused of disintegrating the carrier particles, it is very surprising that the addition of the mixture helps to keep the carrier particles intact. Against this background, it will be apparent to add a mixture to achieve the objectives of the invention. It should be noted that in the reactor used in connection with the present invention 20, the initial speed of the stirrer was increased from 15 rpm to 30 rpm in the process according to the invention.

Another way to increase the hydrogen chloride release compensating agent-25 and heat transfer is to change the viscosity of the liquid reaction mixture. viscosity. This can be done as mentioned above by selecting a suitable dispersion medium such as a C5-C8 hydrocarbon, but it can also be done by adding an excess viscosity reducing liquid to the reaction mixture.

30

Yet another means of equalizing the hydrogen chloride formed in the reaction; shrinkage is the use of overpressure during the reaction. Overpressure has both thermodynamic and physical effects on the release of hydrogen chloride. The thermodynamic effect is based on the inhibition of the evaporation of hydrogen chloride, which is reflected back to and slows down the equilibrium reaction that may generate hydrogen chloride. The physical effect is based on the fact that the higher pressure raises the hydrogenation temperature of hydrogen chloride and 8 92327 prevents gasification in a certain temperature. According to one embodiment, an overpressure of the order of 1 to 100 bar, more preferably about 1 to 50 bar and most preferably about 1 to 5 bar is used during the reaction.

5

The release of hydrogen chloride formed in the reaction can be offset by introducing nitrogen gas into or over the reaction mixture. The use of the inert gas stream mainly acts physically in such a way that the reduced hydrogen chloride content in the environment accelerates the removal of the hydrogen chloride generated in the reaction from the pores, whereby the saturation point of hydrogen chloride corresponding to the pore gasification is never reached. However, nitrogen or other inert gas should be used with caution. Silia has a thermodynamic effect, i.e. by rapidly removing hydrogen chloride from the porous hydrogen chloride of the carrier particles, the possible equilibrium reaction is accelerated and produces a large amount of hydrogen chloride-inducing lamp.

The complex particle and can may be added to the reaction mixture

A liquid that dissolves the non-gasifiable product of the silent reaction of TiCl4. As described above in the reaction compound (1), the silent reaction of the MgCl2-C2H5OH complex and TiCl4 results in the addition of activated magnesium chloride and hydrogen chloride to give ethoxytitanium trichloride having the same presence in the same solution? with hydrogen chloride reduces the hydrogen chloride capacity of the solution and thus the gassing capacity of myOs hydrogen chloride. The addition of ethoxytitanium trichloride solubilizing agent can increase the hydrogen chloride release state and equalize its release according to the amount of the invention. The products of the silent reaction of the complex with TiCl4, such as ethoxytitanium trichloride and hydrogen chloride, can also be removed by exchanging excess TiCl4 during the reaction.

35 As shown in the preliminary experiments, the composition of the MgCl2-C2H50H complex has a decisive influence on the strength of the hydrogen chloride formed in the silent reaction of the complex and TiCl4.

II

9 92327 is released. Preliminary results and reaction equation (1) show that the discharge rate increases with increasing concentration of C2H5OH in the complex. At the same time, however, the ability of MgCl2 to be Akti-activated with TiCl4 decreases, so that the ethanol content of the complex, which can theoretically vary between 1 and 6 steps, is optimum, depending on how effectively the release of hydrogen chloride in the reaction can be compensated by other means. . According to one embodiment of the invention, the molar ratio of MgCl 2 -C 2 H 5 OH-10 complex used as the carrier particle material is 2.5-3.5 and preferably about 2.7-3.3 of MgCl 2 and C 2 H 5 OH. Since excessive ethanol concentrations almost always cause hydrogen chloride discharges that disrupt the carrier particles, it can be generally said that the C2H5OH content of the complex must be less than about 60% by weight of the proca-15 catalyst.

Since too large carrier particles break more easily and, due to their deep pore structures, emphasize the factors contributing to the rapid discharge of hydrogen chloride, it is preferable to use carrier particles smaller than about 150.

The success of the invention is also influenced by the water content, mechanical strength, particle morphology and particle size distribution of the carrier particles. Therefore, it has been found that carrier particles consisting of the MgCl2-C2H5OH complex prepared by the spray crystallization process are particularly suitable for the process according to the invention. According to a preferred embodiment, a complex melt having a composition of MgCl 2 · 3.5C 2 H 5 OH and a temperature of about 120-130 ° C is sprayed through a diffusing nozzle structure into a chamber having a temperature of about 30-50 ° C, in which case the solid droplets

a second zone with a temperature of about 10 ° C

lower and where the particles are stunned permanently. Particles prepared by such a process are mechanically much stronger than, for example, particles prepared by spray evaporation and are thus particularly well suited to the invention. . method in which the tendency to discharge hydrogen chloride imposes high mechanical requirements on the particles. At the same time, 10 92327 particles are generated, the pore volume of which is suitable for the method according to the invention.

The release of hydrogen chloride can be accelerated by the presence of myOs sisal Dono-5 in the reaction mixture of carrier particles and TiCl4.

This is because the Donor reactions that occur during the addition are usually exothermic. If the donor is added at a stage in a temperature range where hydrogen chloride discharge is possible, it may well lead to uncontrolled release of hydrogen chloride. This is how e.g. occur when the reaction mixture to the TiCl 4 addition fraction is heated to a lamp space of about + 20 ° C and the donor is added to the reaction mixture. According to one embodiment, it is preferred to equalize the release of hydrogen chloride in the reaction upon addition of the internal electron donor to the donor reaction mixture only for about 0.5-6 h, preferably about 2-5 h, with the addition of TiCl 4. It is myds intentional to add the internal donor to the reaction mixture in a controlled manner over about 0.5-1.5 hours. For safety reasons, the heating rate should preferably only be increased for about 1-3 hours with the addition of the donor, so that the addition of the donor does not cause strong hydrogen chloride discharges.

The above measures for balancing the release of hydrogen chloride formed in the reaction according to the invention can be used alone or combined in any way. According to an embodiment of the invention, the measures are used as shown in Figure 5.

Figure 5 shows a lamp state profile according to an embodiment of the invention in the preparation of a procatalyst composition by an external reaction of a MgCl 2 -C 2 H 5 OH complex and TiCl 4. In the figure: A is the slow raising of the lamp state to the first fraction of the first TiCl4 addition, B is the prolongation of the reaction to the donor addition fraction, C is the faster raising of the lamp state to complete the silent first reaction of the carrier and TiCl4,

II

11 92327 D is the completion of the primary reaction between the support and TiCl4, E is the second treatment of the support with TiCl4, F is the washing and 5 G is the drying.

According to the invention, it is preferable to carry out one or more of the above-mentioned steps to compensate for the release of hydrogen chloride formed in the reaction at the points I, II and III indicated in the figure. It is natural for TailiS to perform the steps related to the addition of TiCl4 and the related heating in section I and the corresponding measures related to the addition of the donor in sections II and III. Otherwise, the operations can be optimized for the entire process, keeping an eye on each reactor and the desired product.

As even small impurities can interfere with the reaction and cause excessive hydrogen chloride discharges, the substances must be as pure as possible and especially dry. Special care must be taken with the silencer and inert gas to prevent adverse side reactions. In order to keep the reaction environment as clean as possible, it is preferable to use a multi-purpose reactor with a sieve bottom, which can carry out the activation, washing and drying steps without removing the procatalyst or its by-product from the reactor.

This type of Reaktor! and the method is disclosed in Finnish Patent Publication 83329, which is incorporated herein by reference.

The following are a few comparative examples and embodiments to illustrate the invention.

Condensers 35 The TiCl4 used in the synthesis was liquid and aqueous.

The MgCl2-C2H5OH complex carrier was prepared from a complex melt to give MgCl2 * 3.5C2H5OH. Melt 12 92327 was sprayed at a temperature of about 120-130 ° C through a decomposing nozzle structure into a chamber having a lamp space of about 30-50 ° C in the receiving chamber. From the receiving zone, melt droplets were passed through a slightly cooling zone to finally cure the particles. Finally, the particles were screened to a particle size of less than about 150. The composition of the final particles was about MgCl 2 * 3C 2 H 5 OH.

The morphology of the carrier particles was excellent. The particle size-10 drop was valence 1.50-3.4 (span) and the particles did not contain finely divided material. Microscopic images of the support particle are shown in conjunction with microscopic images of procatalysts and polymers in the processing of the results.

15 Comparative Example 1

A multi-purpose reactor with a sieve bottom and a volume of 1.5 m3 was cooled to -20®C. An inert hydrocarbon solvent (Liquid product LIAV), TiCl 4 and a support, MgCl 2 · 2.7C 2 H 5 OH, were then added to the reactor in that order. The mSårå of the carrier was 44 kg and the ratio of TiCl4 (mole) / carrier C2H5OH (mole) was 10. The ratio of LIAV (kg) / carrier (kg) was 4.5 and the ratio of TiCl4 (mole) / Mg (mole) was 30. The mixing speed was 15 rpm.

25

After the addition of the reagent, the temperature was slowly raised at a rate of 0.22 ° C / min to + 20 ° C. The stirring speed was still 15 rpm.

Five hours after the addition of the reagent, a diisobutyl phthalate (DIBP) donor was added at a temperature of + 20 ° C so that the donor (mol) / Mg (mol) ratio was 0.15. The temperature was then raised to 110 ° C at an average rate of about 0.1 ° C / min. The stirring speed was still 15 rpm. The temperature and stirring were maintained for about 1 hour, after which the activation solution with excess TiCl 4 was removed by rinsing the bottom of the reactor screen.

13 92327

A second treatment with TiCl 4 was performed by adding the reagent to the purified solid intermediate. The temperature was still 110 ° C, the stirring speed 15 rpm and the reaction time 2 hours. The ratio of TiCl4 (mole) / Mg (mole) was still 30.

5

Finally, the product was washed four times with a hydrocarbon solvent (LIAV) so that the ratio of LIAV (kg) / carrier (kg) was 9. During the washing, the stirring speed was approximately the same as before. The product was then dried under a stream of N2 gas at a temperature of 10 to 70 ° C without stirring.

In the context of this comparative experiment, it was found that when the support was added over TiCl4, the mixture started to boil already at a temperature of -20 ° C. The particle size distribution of the catalyst product was such that 64.7% by weight of it had a diameter of less than 20 μτη. The d50 was 17 μπι and the width, or span, of the particle size distribution was 3.1. The proportion of fines in the catalyst-produced polymer was 70% by weight (d <1 mm) and the bulk density was 0.43 g / ml.

20 Comparative Examples 2-5

A multi-purpose reactor with a sieve bottom and a volume of 1.5 m3 was cooled to -20 ° C. An inert hydrocarbon solvent (Liquid product LIAV), 25 kg of support, MgCl 2 · 3.0C 2 H 5 OH and TiCl 4, was then added to the reactor, respectively. The ratio of TiCl 4 (mole) / carrier C 2 H 5 OH (mole) was 10, the ratio LIAV (kg) / carrier (kg) was between 4.5-9 and the ratio TiCl 4 (mole) / Mg (mole) was 30. The stirring speed was 15 rpm.

After the addition of the reagents, the temperature was slowly raised at a rate of about 0.22 ° C / min to + 20 ° C. The stirring speed was still 15 rpm. 3-5 hours after the addition of the reagents, diisobutyl phthalate (DIBP) donor was added at a temperature of + 20 ° C so that the ratio of donor (mole) / Mg (mole) was 0.15. 35

The temperature was then raised to 110 ° C at an average rate of about 1 ° C / min. The stirring speed was still 15 rpm. The temperature and stirring were maintained for about one hour, after which the activation portions of T-14 92327 with excess TiCl4 were removed by rinsing the bottom of the reactor screen.

A second treatment with TiCl 4 was performed to add reagent 5 to the purified solid product. The lamp state was still 110 ° C, the stirring speed 15 rpm and the reaction time about two hours. The ratio of TiCl4 (mole) / Mg (mole) was still 30.

Finally, the product was washed four times with hydrocarbon solvent 10 (LIAV) so that the ratio of LIAV (kg) / carrier (kg) was 9. During the washing, the stirring rate was approximately the same as before. The product of this fraction was dried under a stream of N 2 gas at 70 ° C without stirring.

15 In the case of the women's comparative experiments, it was found that gas was evolved during heating. The particle size distribution of the catalyst product was such that 11-28% by weight of it had a diameter of less than 20. The d50 was a range of 30-62 μm and the width or span of the particle size distribution was a range of 1.46-2.96. The other 20 features are presented in the context of the results.

Execution Examples 1-4

A multi-purpose reactor with a sieve bottom and a volume of 25 was 1.5 m3 and was cooled to -20 ° C. A hydrocarbon solvent (Liquid product LIAV), a carrier, MgCl 2, 3.0C 2 H 5 OH and TiCl 4, were then added to the reactor, respectively. The amount of carrier ranged from 24 to 29 kg and the ratio of TiCl 4 (mole) / carrier C 2 H 5 OH (mole) was 10. The ratio LIAV (kg) / carrier (kg) was 30.0 and the ratio TiCl 4 (mole) / Mg (mole) was 30.

In contrast to the comparative example, the initial stirring speed was 30 rpm, the initial overpressure of the reactor was 2.5 bar and dry N 2 gas was passed through the reactor at a flow rate of 5 to 35 kg / h, until the maximum lamp state was reached.

The lamp space of the reagent addition was slowly raised at a rate of about 0.22 ° C / min to + 20 ° C. At this stage, the amount of agitation was reduced from the original value of 30 rpm to the normal value of 15 rpm to reduce the mechanical stress caused by the agitation.

5 After the addition of the reagents, the diisobutyl phthalate (DIBP) donor was added to the reactor at room temperature + 20 ° C so that the donor ratio! (moles) / Mg (moles) was 0.15.

The ldmpOt state was then raised at an average rate of about 1 ° C / min 10 to a maximum value of 110 ° C, whereby the overpressure and the N 2 flow were removed. The stirring speed was still 15 rpm. The LdmpO state and agitation were maintained for about one hour, after which the Akti lubrication portions with excess TiCl4 were removed by rinsing the reactor screen bottom.

15

Second Treatment with TiCl 4 was performed with additional reagent in purified clintin intermediate. The temperature was still 110 ° C, the stirring speed 15 rpm and the reaction time two hours. The ratio of TiCl4 (mole) / Mg (mole) was still 30.

20

Finally, the product was washed three times with a hydrocarbon solvent (LIAV) so that the LIAV (kg) / carrier (kg) ratio was 9. During the washing, the stirring rate was approximately the same as before. The product was then dried under a stream of N2 gas at room temperature to 70 ° C without stirring.

In connection with these performance experiments, no boiling of the reaction mixture during heating was observed. The particle size distribution of the catalysts was such that 21-22% by weight of the particles 30 had a diameter of less than 20. The d50 was 44-62 μm and the width of the distribution, i.e. the span number, was 2.25-2.59 (except in the fourth pilot experiment). Other features are presented in connection with the analysis of the results.

35 Test polymerization

All laboratory and pilot scale procatalysts of the Comparative and Performance Examples were tested under standard polymerization conditions. A two-liter bench reactor was used. 20-30 mg of procatalyst was used in each experimental polymerization run. 620 pml of triethylaluminum cocatalyst and 200 pml of a 25% heptane solution of an internal cyclohexylmethylmethoxysilane donor were mixed into the soil. the active ingredient was 30 ml of heptane. The polymerizations were carried out at a temperature of + 70 ° C and a propylene monomer pressure of 10 bar. The partial pressure of hydrogen during the polymerization was 0.2 bar. The polymerization was continued for three hours. The activity of the procatalyst of that fraction was measured on the basis of the polymerization yield. The soluble fraction of the polymer was measured by dissolving the determined amount of polymer in the solvent and measuring the evaporation rate of the pure solution.

Bulk density and particle size distribution were determined from all polymer samples. In connection with the particle size distribution measurements, the total amount of finely divided material was estimated. All polymer particles with a diameter of less than 1 20 mm were defined as TailOin fine material. Isotacticity was measured by heptane elution and the isotacticity index was measured using the results of evaporation measurements. The melt index was measured at 230 ° C using a weight of 2.16 kg.

25 Results

The test runs described above have been performed on a pilot scale. The initial experiments were performed in the laboratory. TS11Oin was found to have problems on a pilot scale that did not occur on a laboratory scale. In the laboratory experiments, the release of hydrogen chloride gas was uniform in all experiments, while in the pilot scale in the comparative examples there was a strong discharge of hydrogen chloride gas as opposed to performance experiments in which the release of hydrogen chloride was able to be equalized by the measures of the invention.

The release of hydrogen chloride was monitored in Examples 1 to record the extent to which the reactor exhaust gas was able to open the reactor-pressure exhaust valve connected to the reactor. Figure 6 shows the opening of a valve as a function of temperature and time. The figure above shows the gradient of the reaction state of the reaction, i.e. the profile, and the lower one shows the opening of the valve, i.e. the escape rate of hydrogen chloride gas as a function of time. The escape rate of hydrogen chloride is relatively constant and does not show any peaks when heated as shown in Figure 3.

The laboratory and pilot scale procatalysts of the Examples had titanium content, donor content, particle size distribution, catalyst yield, catalyst activity, polymer isotacticity, polymer melt index, and polymer bulk density for normal types of catalysts.

The titanium content ranged from 2.9 to 3.6% by weight of valine on laboratory procatalysts and from 2.4 to 4.5% by weight of valine on pilot procatalysts. The donor concentration ranged from 15.9 to 19.2% by weight of valil for laboratory procatalysts and from 9.7 to 15.4% by weight of valil for pilot procatalysts (in Example 1, the donor sample of pilot scale failed).

The particle size distribution of procatalysts is shown in Table 1.

Only in the last, i.e. the fourth, pilot-scale preparation was a small procatalyst decomposition observed, which is manifested as a wider distribution with a span number of 3.41.

Procatalyst yield was satisfactory, ranging from 74 to 99% valence at pilot times and 82 to 92% valence in the laboratory. This shows, for example, that the finely divided material has not been rinsed off in a larger pilot run than in a laboratory run.

35

The activity of the pilot procatalysts was at best 15.8 kgPP / g cat, which is a good value and of the same order of magnitude as the procatalysts prepared in the laboratory.

18 92327

Polymer isotacticity ranged from 98.9 to 99.3% for laboratory procatalysts (index between 98.3 to 98.9%) and from 96.8 to 97.5% (index between 93.3 to 98.1) for pilot procatalysts. at a satisfactory level.

5

The polymer melt indexes ranged from 4.3 to 9.6 for laboratory procatalysts and from 5.0 to 7.4 (10.4) for pilot procatalysts (the fourth run MI was exceptionally 19.4), corresponding to the melt index of normal polypropylene.

10

Polymer bulk densities ranged from 0.41 to 0.47 g / ml for laboratory procatalysts and from 0.40 to 0.44 g / ml for pilot procatalysts.

Particular attention was paid to the particle size distribution of the polymeric material provided by the procatalysts prepared by the process of the invention. The results are shown in Table 2. A graphical representation can be found in Figure 7.

Table 2 (see page 20) only shows the particle size distribution of the polymers obtained with the laboratory and pilot procatalysts according to Embodiment 1-4, while Figure 7 compares the particle size distribution obtained with the laboratory and pilot procatalysts prepared according to the comparative examples. - 25 mers and polymers made with laboratory and pilot catalysts according to the working examples. It is clear from the figure that the comparative examples and the working examples give the same type of results in the case of laboratory-scale procatalyst synthesis.

30

By moving to a pilot scale, the measures according to the invention provide a considerable improvement over the procatalysts according to the comparative examples. In the pilot-mit guarantee, the proportion of finely divided polymer material is reduced to at least about a quarter and at most to less than a tenth compared to the results of the comparative tests. In Pilot Comparative Example 1, which contained the order of addition of the various reagents (see instructions above), the proportion of finely divided substance 19 92327 was obtained up to 70% by weight, which value is much higher than the values of the pilot examples.

Figures 8-13 show electron micrographs of the support of Example 5 (Figure 8), the laboratory procatalyst (Figure 9), the pilot procatalyst (Figure 10), the polymer obtained with the laboratory procatalyst (Figure 11) and the polymer obtained with the pilot procatalyst (Figure 11). Figure 12). The images of this Embodiment 1 visually represent well the morphology of the product 10 from the spray-crystallized support to the finished polypropylene product. Comparing Figures 8, 10 and 12, it can be seen that the proportion of fines in the polymer or procatalyst is not much higher than in the support. Comparing Figures 10 and 12 to Figures 9 and 11, it can be seen that both the procatalyst and the polymer are slightly more agglomerated in the pilot scale synthesis than in the laboratory scale synthesis. However, this trend was not as strong in performance trials 2-4.

20 92327

Table 1 Particle size distribution of procatalysts prepared on a pilot and laboratory scale.

5 Execution D (0.1) D (0.5) D (0.9) Span example pm pm pm

Pilot 1 8.4 44.3 108.1 2.25 2 6.7 52.4 142.3 2.59 10 3 11.8 80.4 108.6 2.17 4 7.5 38.7 139 5 3.41

Laboratory 1 6.1 36.8 106.9 2.75 2 10.7 63.8 203.6 3.02 15 3 7.4 44.0 107.2 2.27 4 6.3 51.1 119, 8 2.22 20

Table 2 Polymer particle size distributions of catalysts on a pilot and laboratory scale.

25 - * Performance- Prokata- 2.0 1.0 0.5 0.18 0.1 example lyt mm mm mm mm mm 1 Pilot 45.0 45.6 8.9 0.5 0.0 30 Lab 67, 9 30.1 1.5 0.3 0.1 2 Pilot 47.1 46.8 4.5 0.9 0.4

Lab 65.0 31.5 3.4 0.3 0.0 3 Pilot 61.2 29.7 7.2 1.6 0.3

Lab 64.4 31.1 3.6 0.7 0.2 35 4 Pilot 50.6 41.3 7.1 0.9 0.1

Lab 38.6 48.7 10.6 1.5 0.5

Claims (19)

A process for the preparation of a procatalyst composition for polymerization of olefins by reacting carrier particles of a MgCl2-C2H5OH complex with TiCl4 / wherein hydrogen chloride is formed, characterized by the use of one or more for 0.5-3.0 hours to a liquid suspension of the carrier particles; b) TiCl4 was added at a temperature of -30 ...- 10 ° C; c) the temperature was raised during the addition of TiCl4 or thereafter at a rate of about 5 -20 ° C / h between -20 ... + 40 ° C, d) during the reaction, a strong stirring is achieved, e) a viscosity-reducing liquid is used in the reaction mixture, f) during the reaction an overpressure of the order of magnitude is used. 1-100 bar, g) Nitrogen gas is passed into the reaction mixture or thereafter, and h) In the reaction mixture, a liquid Idser product is used between the carrier particles and TiCl4 in such a way that the release of hydrogen chloride per minute is started. is boiled to a maximum of 5% of the total amount of hydrogen chloride produced in the reaction, for maintaining the carrier particles in a complete state. 1 2. A process according to claim 1, characterized in that the release of the chlorine wet generated in the reaction is smoothed in the reaction or reaction mixture to a molar rate which does not exceed the five-fold maintenance of the average molar release rate. 26 92327 3. A method according to claim 1 or 2, characterized in that the release of the chlorine wet generated in the reaction is smoothed to a volume rate which does not exceed the triple, sheep wire, twice the care of the average volume speed of the release. 4. A process according to claim 1, 2 or 3, characterized in that the release of hydrogen chloride from the carrier complex or reaction mixture is limited so that the release per minute is less than about 2% of the total amount of hydrogen produced in the reaction. Process according to claim 1, 2, 3 or 4, characterized in that the release of the chloride wet generated in the reaction is smoothed by a controlled addition of TiCl4 for 1.0 hour in the liquid suspension of carrier particles. Process according to one of the preceding claims, characterized in that TiCl 4 was added at the temperature 20 - 25 ... - 15 ° C. Process according to one of the preceding claims, characterized in that the temperature is raised during the addition of TiCl4 or thereafter at a rate of about 5-15 ° C / h between about -20 ... + 40 ° C. 8. A process according to any one of the preceding claims, characterized in that the release of the hydrochloride produced during the reaction is smoothed by applying overpressure during the reaction, which sheep threads are of the order of 1-50 bar, preferably about 1-5 bar. 9. A process according to claim 8, characterized in that a TiCl4 excess is used as a locking liquid, the reaction product of the MgCl2-C2H5OH complex and TiCl4 is obtained and that during the reaction TiCl4 is replaced with a new TiCl4 which is then locked down. 27 92327 Process according to any one of the preceding claims, characterized in that an MgCl2-C2H5OH complex is used, in which the molar ratio of MgCl2 to C2H5OH is between 2.5 and 3.5, preferably between 2.7 and 3.3. 5 A process according to any one of the preceding claims, characterized in that an MgCl2-C2H5OH complex is used, our C2H5OH content is less than 60% by weight. 12. A method according to any of the preceding claims, characterized by the use of carrier particles, the size of the spring is about 150 μιη. A process according to any one of the preceding claims, characterized in that the carrier particles of the MgCl2-C2H5OH complex have been prepared by spray crystallization. Process according to any one of the preceding claims, characterized in that the release of the chlorine wet generated in the reaction is smoothed in conjunction with the addition of the electron donor so that the donor is added to the reaction mixture for about 0.5-6 hours, preferably about 2-5 hours. h, after the addition of TiCl4. 15. A method according to claim 12, characterized in that the internal donor was added to the reaction mixture controlled for 0.5 to 1.5 hours. 16. A process according to claim 12 or 13, characterized in that the heating rate is first increased about 1-3 hours after the addition of the donor and the raising of the temperature is terminated at about 110-120 ° C. 17. A method according to any one of the preceding claims, characterized in that substantially the following temperature profile is used: 28 92 32 c c c c c Y Y G 10 K 'A' A denotes a rise in temperature after understanding the addition of TiCl4, B denotes a vaporization of the reaction after the addition of the donor, C denotes a faster rise in temperature to complete the reaction between the carrier and TiCl4, D denotes a termination of the understood reaction between the support and TiCl 4, E denotes the second treatment of the support with TiCl 4, F denotes two and 25. denotes drying. carried out at points I, II and III. 18. A method according to claim 17, characterized in that in point I, the yards according to claims 1a), 1b), 1c), 5, 6 and / or 7 and in points II and III are carried out the yards according to claims 14, 15 and / or 16 . 19. A method according to any one of the preceding claims, characterized in that a multifunction reactor equipped with a screen bottom is used, with which the activation, washing and drying steps can be carried out without removing the procatalyst or the intermediate product from the reactor. 92327% hannoj akoista (<1 rrm) 80-i ---- 67.8 ^ I 38.2 36.4 AB CD Kantoaine Kuva 1 Hienojakoisen aineen muodostuminen PP-polymer verrattaessa pilot-catalytic laboratory laboratory catalytic acid. 60-j-HCl: n maximum 50 - Q- vapautumisnope- • us mcoli / min 40 - O · “lampotilassa ^ 10-20eC 30-yr 20- β” ° ψ 0 4 --- 1-i- | -> - | -> - 1 -.- 0 10 20 30 40 50 Polymerine hannojakoisen aineen osuus (%) Kuva 2 Correlation of polymerine hanno jakoisen fraction but yes catalytic synthesis synthesis of HCl maximum vapoma tumisnopeuden (ml / min) valilla. 92327 NaOIl KuluLus, ml 300j --- 200 L ...................................... \ i '' - & Γ 1—1 ϋ '' '' b'0 '' u) o '' itio '' l.amfKiki] a, C Kuva 3 I IC]. ^ I1 ~ coinplexia, UCl: a ja TiCl ^ ta sisaltavaa systieemia aika, min. dV / dT, ml NaOIl / ° C 0 50 100 20j ...... | Ί · t — T "T" I '1 1 II) 15- 10 5 -io S 1 $ 5 1 & 1 Si Sr ~ lampotila, ° C Kuva 4 IlCl-vapaulumisnopeus laiiipOLilan funkLiuna, systemi sisSltSa M9Cl2-C2II50n-koiiiL only) lesson, TlCl ^: a yes IK31: a. 92327 i D E π ../ v i f Factio- f j \ I — y — ψ-y— lampo- \ ^ tila / c II___ / jLl / | _g processialka Kuva 5 Keksinnon mukaisten toimenpiteiden edullinen kaytto procatalyyttiprocessissa; (A) hidas lampotilan lisåa mine TiCl 2 -lisayksen jalkeen, (B) reaction pitkittåmien donorin lisaåmisen aikana ja jalkeen, (C) lampotilan lisays reaction loppuun saattamiseksi, (D) ensimmainen titanointi, (E) toinen titan ) pesu, (G) kuivaus 92327 / Π 25/09/1991 04; 13. = 21 85.41 c II - 149.9 t -----: - "Ί T / ° C - II - -20.9 I-1--1-1-1 -3H -6H -4H t / h -2H EH Sat PIC-6523 REACTOR DC-6502 HAKSIMIPA1NE / Q 25.03.1991 04: 13 = 27 52.58 * ||: loop.ø Λ A "- \: dT —T Ί N i-1-M-LH — 1“ * _-8H_-6H_-4H t / h -2H ØH ^ B ····································································lated 25.09.1931 Kuva 6 Chloro-dyne vapautumisnopeus (alenpi kayra) loanpotilagradientin (ylenpi kayra) ja ajan functa . 92327 lab. cat lab. cat pilot cat. pilot cat. Hipnn-ia vanha uusi vanha uusi jcoista ~ 2SSSS mmm »a bssss ainetta% 80 i- 11'7 60 5.6 W 52.9 pp 40 ^ ^ ^ 1 2 3 4: Kuva 7 Hieno j ako isen aineen (d < 1 rrrn) coconaisnvaara vertailuesimer mark (vanha) yes suoritusesimerkkien laboratory- yes pilot-catalytic catalytic valmistetuissa polyiteereissa.