PROCESS FOR MAKING PROPYLENE-BASED TERPOLYMER

20210292449 · 2021-09-23

    Inventors

    Cpc classification

    International classification

    Abstract

    The invention relates to a process for production of terpolymers, in particular for the polymerization of propylene, and two other distinct monomers chosen from a group comprising ethylene and a C4-C12 α-olefin in a horizontal stirred reactor comprising an agitated bed and several reaction zones for forming polymer particles.

    Claims

    1. A process for production of a propylene based terpolymer, comprising: propylene, a first distinct monomer selected from ethylene or C4-C12 α-olefin, a second distinct monomer selected from ethylene or C4-C12 α-fin, wherein the first distinct monomer and the second distinct monomer are not the same, and the said process is performed in the presence of a catalyst system in a horizontal stirred reactor (100) comprising: an agitated bed for forming polymer particles, a plurality of liquid feed ports (111, 112) that are subsequently arranged along a top side of the reactor above the agitated bed, the plurality of liquid feed ports comprising at least a first set of the liquid feed ports (111) and a second set of the liquid feed ports (112) arranged subsequent to the first set of the liquid feed ports in a downstream direction of the process, and a plurality of gas feed ports (114, 115) that are subsequently arranged along a bottom side of the reactor below the agitated bed, the plurality of gas feed ports comprising at least a first set of gas feed ports (114) and a second set of gas feed ports (115) arranged subsequent to the first set of gas feed ports in the downstream direction of the process, a plurality of reactor off-gas ports (116) that are arranged along a top side of the reactor above the agitated bed. wherein the process comprises the steps of: recovering a reactor off-gas (117) comprising H.sub.2, propylene, and said first and second distinct monomers from the reactor through the reactor off-gas ports (116), feeding the reactor off-gas (117) to a condenser (150) to form a gas-liquid mixture (118), feeding the gas-liquid mixture (118) to a separator (140) to obtain a first gas stream (121) and a first liquid stream (119): the first gas stream (121) comprising: H.sub.2, propylene, and one or both of the first and second distinct monomers, in an higher mole fraction than in the first liquid stream when they are lighter than propylene and the first liquid stream (119) comprising: H.sub.2, propylene, and one or both of the first and second distinct monomers, in an higher mole fraction than in the first gas stream when they are heavier than propylene, wherein fresh propylene is optionally further fed to the system, through the separator (140) and/or added to the first liquid stream (119), feeding the catalyst system to the reactor through a port arranged on the top side of the reactor, feeding a H.sub.2 poor quench liquid (101) comprising propylene through the first set of the liquid feed ports (111), feeding a H.sub.2 rich quench liquid (103) comprising: H.sub.2, propylene, and the first and second distinct monomers, to the reactor through the second set of liquid feed ports (112), wherein the H.sub.2 rich quench liquid (103) comprises at least part of the first liquid stream (119), feeding a H.sub.2 poor bottom gas (102) comprising fresh propylene through the first set of gas feed ports (114), feeding a H.sub.2 rich bottom gas (104) comprising: H.sub.2, propylene, and the first and second distinct monomers through the second set of gas feed ports (115), wherein the H.sub.2 rich bottom gas (104) comprises at least part of the first gas stream (121), and collecting the polymer particles formed in the agitated bed from the reactor, wherein the said process comprises the further following steps: at least one fresh of the two distinct monomers when it is lighter than propylene, is fed to: the reactor as a part of the H.sub.2 poor bottom gas (102) and/or as part of the H.sub.2 rich bottom gas (104) and/or fed to the separator (140); at least one fresh of two distinct monomers when it is heavier than propylene, is fed: to the reactor as: a part of the H.sub.2 poor quench liquid (101) and/or a part of the H.sub.2 rich quench liquid (103) and/or to the separator (140).

    2. The process according to claim 1, wherein: the said first distinct monomer is ethylene, and the said second distinct monomer is C4-C12 α-olefin.

    3. The process according to claim 1, wherein a part (122) of the first liquid stream (119) is fed to a H.sub.2 stripper (160) to remove H.sub.2 to form a second liquid stream comprising propylene and the first and second monomers.

    4. The process according to claim 3, wherein at least part of the second liquid stream is fed to the reactor as a part of the H.sub.2 poor quench liquid (101).

    5. The process according to claim 3, wherein at least part of the second liquid stream is vaporized and fed as a part of the H.sub.2 poor bottom gas (102).

    6. The process according to claim 1, wherein the reactor off-gas is fed to a cyclone from which polymer particles are carried back to the reactor by means of the H.sub.2 poor gas stream (102).

    7. The process according to claim 1, wherein said at least one of two distinct monomers is 1-hexene.

    8. The process according to claim 1, wherein the catalyst system is a Ziegler-Natta catalyst system, wherein the Ziegler-Natta catalyst system comprises a procatalyst, a co-catalyst and optionally an external electron donor, wherein the procatalyst is obtained by a process comprising the steps of Step A) providing or preparing a compound R.sup.4.sub.zMgX.sup.4.sub.2-z wherein R.sup.4 is independently selected from linear, branched or cyclic hydrocarbyl group independently selected from alkyl, alkenyl, aryl, aralkyl, or alkylaryl groups, and one or more combinations thereof; wherein said hydrocarbyl group is substituted or unsubstituted, and optionally contain one or more heteroatoms; X.sup.4 is independently selected from the group consisting of fluoride (F—), chloride (CI—), bromide (Br—) or iodide (I—); z is in a range of larger than 0 and smaller than 2, being 0<z<2; Step B) contacting the compound R.sup.4.sub.zMgX.sup.4.sub.2-z with a silane compound Si(OR.sup.5).sub.4-n(R.sup.6).sub.n to give a first intermediate reaction product, being a solid Mg(OR.sup.1).sub.xX.sup.1.sub.2-x wherein R.sup.1, R.sup.5 and R.sup.6 are each independently selected from linear, branched or cyclic hydrocarbyl group independently selected from alkyl, alkenyl, aryl, aralkyl, alkoxycarbonyl or alkylaryl groups, and one or more combinations thereof; wherein said hydrocarbyl group is substituted or unsubstituted, and optionally contain one or more heteroatoms; X.sup.1 is independently selected from fluoride (F—), chloride (CI—), bromide (Br—) or iodide (I—); n is in range of 0 to 4; z is in a range of larger than 0 and smaller than 2, being 0<z<2; x is in a range of larger than 0 and smaller than 2, being 0<x<2; Step C) activating said solid support, comprising two sub steps: Step C1) a first activation step by contacting the first intermediate reaction product obtained in step B) with at least one first activating compound being a metal alkoxide compound of formula M.sup.1(OR.sup.2).sub.v-w(OR.sup.3).sub.w or M.sup.2(OR.sup.2).sub.v-w(R.sup.3).sub.w; wherein: M.sup.1 is a metal selected from Ti, Zr, Hf, Al or Si; M.sup.2 is a metal being Si; v is the valency of M.sup.1 or M.sup.2 and w is smaller than v; R.sup.2 and R.sup.3 are each a linear, branched or cyclic hydrocarbyl group independently selected from alkyl, alkenyl, aryl, aralkyl, alkoxycarbonyl or alkylaryl groups, and one or more combinations thereof; wherein said hydrocarbyl group is substituted or unsubstituted, and optionally contain one or more heteroatoms; and a second activating compound being an activating electron donor; and Step C2) a second activation step by contacting the activated solid support obtained in step C1) with an activating electron donor; to obtain a second intermediate reaction product; Step D) reacting the second intermediate reaction product obtained step C2) with a halogen-containing Ti-compound, optionally an activator prior to or simultaneous with the addition of an internal donor, and at least one internal electron donor to obtain said procatalyst.

    9. The process according to claim 1, wherein the reactor is provided with two reaction zones that are arranged subsequent to each other in the downstream direction of the process, wherein a first reaction zone (110) of said two reaction zones is fed with the H.sub.2 poor quench liquid (101) and the H.sub.2 poor bottom gas (102), and a second reaction zone (120) of said two reaction zones is fed with the H.sub.2 rich quench liquid (103) and the H.sub.2 rich bottom gas (104).

    10. The process according to claim 1, wherein the reactor is provided with three reaction zones that are arranged subsequent to each other in the downstream direction of the process, wherein a first reaction zone (110) of said three reaction zones is fed with the H.sub.2 poor quench liquid (101) and the H.sub.2 poor bottom gas (102), a second reaction zone (120) of said three reaction zones is fed with either i) the H.sub.2 poor quench liquid (101) and the H.sub.2 rich bottom gas (104) or ii) the H.sub.2 rich quench liquid (103) and the H.sub.2 poor bottom gas (102), and a third reaction zone (130) of said three reaction zones is fed with the H.sub.2 rich quench liquid (103) and the H.sub.2 rich bottom gas (104).

    11. The terpolymer composition obtained by or obtainable by the process according to claim 1.

    12. Setup assembly for the production of terpolymers comprising at least: A horizontal stirred reactor (100) comprising an agitated bed for forming polymer particles with at least two reaction zones, a plurality of liquid feed ports (111, 112) that are subsequently arranged along a top side of the reactor above the agitated bed, the plurality of liquid feed ports comprising a first set of the liquid feed ports (111) and a second set of the liquid feed ports (112) arranged subsequent to the first set of the liquid feed ports in a downstream direction of the process, and a plurality of gas feed ports (114, 115) that are subsequently arranged along a bottom side of the reactor below the agitated bed, the plurality of gas feed ports comprising a first set of gas feed ports (114) and a second set of gas feed ports (115) arranged subsequent to the first set of gas feed ports in the downstream direction of the process a plurality of off-gas ports (116) arranged along a top side of the reactor above the agitated bed in a downstream direction of the process a recycle loop comprising: a condenser (150) connected to the horizontal stirred reactor (100) by the plurality of off-gas ports (116), and a separator (140) connected to the condenser by a gas liquid mixture line (118) and to the horizontal stirred reactor by a first liquid stream line (119) to the second set of the liquid feed ports (112), and a first gas stream line (121) to the second set of gas feed ports (115).

    13. Setup assembly according to claim 12, wherein it also comprise a stripper (160) configured to remove at least H.sub.2 and connected to to the separator (140) through a liquid stream line (122) which is a part of the first liquid stream (119) to the first set of the liquid feed ports (111) of horizontal stirred reactor (100) through a poor H.sub.2 line configured to carry on a H.sub.2 poor quench liquid produce by the stripper, and to the condenser (150) through a rich H.sub.2 line (123).

    14. Setup assembly according to claim 12 wherein it is configured for carry out the process.

    15. Propylene composition comprising the terpolymer composition obtained by or obtainable by the process of claim 1 and optional additives.

    Description

    BRIEF DESCRIPTION OF THE FIGURES

    [0264] The invention is now elucidated referring to the drawings in which:

    [0265] FIGS. 1 to 5 show a schematic representation of examples of a system for carrying out the process of the invention comprising a reactor with two reaction zones;

    [0266] FIGS. 6 and 7 show a schematic representation of further examples of a system for carrying out the process of the invention comprising a reactor with two reaction zones and a stripper column;

    [0267] FIG. 8 shows a schematic representation of a further example of a system for carrying out the process of the invention comprising a reactor with three reaction zones;

    [0268] FIGS. 9, 10 and 11, show a schematic representation of further examples of a system for carrying out the process of the invention comprising a reactor with three reaction zones and a stripper column;

    [0269] FIGS. 12a and 12b, show two graphs of the fraction PP produced in regard of the monomer and the melt flow index (MFI), 12a in a state of the art system to produce terpolymer comprising two separate reactor and 12b in a system according to the invention.

    EXAMPLES

    Example 1

    [0270] FIG. 1 shows a schematic representation of a non-limiting example of a system for carrying out the process of the invention, in which a reactor 100 consisting of a first reaction zone 110 and a second reaction zone 120.

    [0271] In this embodiment, the two other distinct monomers chosen from a group comprising ethylene and C4-C12 α-olefin are ethylene and 1-hexene: [0272] fresh 1-hexene is fed to the reactor by feeding the fresh 1-hexene directly to the reactor as a part of the H.sub.2 poor quench liquid 101 and [0273] fresh ethylene is fed to the reactor by feeding the fresh ethylene directly to the reactor as a part of the H.sub.2 poor bottom gas 102.

    [0274] The reactor off gas 117 is condensed by a condenser 150 to provide a gas-liquid mixture 118, whish fed a separator 140 where fresh propylene is added. The separator 140 allows a separation of the gas-liquid mixture 118 into a first liquid stream 119 and a first gas stream 121.

    [0275] The first gas stream 121 is mixed with additional H.sub.2 and the obtained H.sub.2 rich bottom gas 104 is fed to the second reaction zone 120.

    [0276] Thus, in this embodiment, the first reaction zone 110 is fed with the H.sub.2 poor quench liquid 101 and the H.sub.2 poor bottom gas 102.

    [0277] The terpolymer prepared in this first reaction zone 110 has a high molecular weight.

    [0278] The second reaction zone 120 is fed with the H.sub.2 rich quench liquid 103 and the H.sub.2 rich bottom gas 104.

    [0279] The terpolymer prepared in this second reaction zone 120 has a low molecular weight.

    [0280] The 1-hexene concentration would be relatively higher in high molecular weight distribution part and ethylene concentration would be relatively flat over the reactor.

    Example 2

    [0281] In another non-limitative embodiment shown by FIG. 2, fresh ethylene and 1-hexene could be add in the system through the separator 140.

    [0282] In this configuration, 1-hexene and ethylene concentrations would be relatively higher in low molecular weight distribution part.

    Example 3

    [0283] In another non-limitative embodiment shown by FIG. 3, fresh ethylene and 1-hexene could be add in the system after the separator 140: [0284] the fresh 1-hexene and propylene may be added to the first liquid stream 119, as a part of the H.sub.2 rich quench liquid 103. [0285] the fresh ethylene may be added to the first gas stream 121, as a part of the H.sub.2 rich bottom gas 104.

    [0286] In this configuration, 1-hexene and ethylene concentrations would be relatively higher in low molecular weight distribution part.

    Example 4

    [0287] In another non-limitative embodiment shown by FIG. 4, which is the combination of the embodiments shown in FIGS. 1 and 2.

    [0288] The split feed of the fresh 1-hexene and/or ethylene allows to give a flat profile of 1-hexene concentration in the weight distribution and an intermediate profile for ethylene than the one obtain in the embodiments described by FIGS. 1 and 2.

    Example 5

    [0289] In another non-limitative embodiment shown by FIG. 5, a schematic representation of a non-limiting example of a system for carrying out the process of the invention, similar to the one describe in FIG. 1, in which the two other distinct monomers chosen from a group comprising ethylene and C4-C12 α-olefin are 1-butylene and 1-hexene: [0290] fresh 1-butylene and 1-hexene and a part of the fresh propylene are fed to the reactor as a part of the H.sub.2 poor quench liquid 101 and [0291] a part of fresh propylene is fed to the reactor as a part of the H.sub.2 poor bottom gas 102.

    Example 6

    [0292] In another non-limitative embodiment shown by FIG. 6, a schematic representation of a non-limiting example of a system for carrying out the process of the invention, similar to the one describe in FIG. 1 and comprising an additional stripper column 160 configured configured to remove at least H.sub.2 and connected: [0293] to the separator 140 through a liquid stream line 122 comprising a part of the first liquid stream line 119, [0294] to the first set of the liquid feed ports 111 of horizontal stirred reactor 100 through a poor H.sub.2 liquid stream line which is configured to carry on a H.sub.2 poor quench liquid produce by the stripper, and [0295] to the condenser 150 through a rich H.sub.2 stream line 123.

    [0296] In this configuration, the stripper allows for high H.sub.2 lean quench availability.

    Example 7

    [0297] In another non-limitative embodiment shown by FIG. 7, a schematic representation of a non-limiting example of a system for carrying out the process of the invention, in which the two other distinct monomers chosen from a group comprising ethylene and C4-C12 α-olefin are ethylene and 1-hexene: [0298] fresh 1-hexene is fed to the reactor by adding the fresh 1-hexene to the first liquid stream 119 from the separator 140, [0299] a part 122 of the first liquid stream 119 is fed to a stripper 160 to remove H.sub.2 and a part of ethylene to form a second liquid stream comprising in majority propylene and 1-hexene and [0300] the second liquid stream is fed to the reactor as a part of the H.sub.2 poor quench liquid 101.

    [0301] In this embodiment, the 1-hexene concentration and the ethylene concentration in the high molecular weight terpolymer (low H.sub.2 concentration zone) would be lower than in the embodiment of FIG. 6, provided that other process parameters are the same.

    Example 8

    [0302] In another non-limitative embodiment shown by FIG. 8, a schematic representation of a non-limiting example of a system for carrying out the process of the invention, in which the two other distinct monomers chosen from a group comprising ethylene and C4-C12 α-olefin are ethylene and 1-hexene: [0303] fresh 1-hexene is fed to the reactor by feeding the fresh 1-hexene directly to the reactor as a part of the H.sub.2 poor quench liquid 101, and [0304] fresh ethylene is fed to the reactor by feeding the fresh ethylene directly to the reactor as a part of the H.sub.2 poor bottom gas 102.

    [0305] In this embodiment, the 1-hexene concentration and the ethylene concentration in the high molecular weight terpolymer (low H.sub.2 concentration zone) are relatively high.

    [0306] FIG. 8 shows a reactor 100 consisting of a first reaction zone 110, a second reaction zone 120 and a third reaction zone 130.

    [0307] A H.sub.2 poor quench liquid 101 comprising fresh propylene and fresh 1-hexene is fed to the first reaction zone 110 through a first set of liquid ports 111. Also a H.sub.2 poor bottom gas 102 comprising fresh propylene and fresh ethylene is fed to the first reaction zone 110 through a first set of gas port 114.

    [0308] A reactor off-gas 117 comprising H.sub.2, ethylene, propylene and 1-hexene is recovered from the reactor through a set of off-gas ports 116.

    [0309] The reactor off-gas 117 is condensed by a condenser 150 to provide a gas-liquid mixture 118, which is fed to a separator 140.

    [0310] The separator 140 is also fed with fresh propylene.

    [0311] The separator 140 provides a first liquid stream 119 comprising essentially propylene and 1-hexene as well as H.sub.2 and ethylene dissolved in the liquid mixture of propylene and 1-hexene and a first gas stream 121 comprising essentially H.sub.2, ethylene and propylene.

    [0312] The first gas stream 121 is mixed with additional H.sub.2 and the obtained H.sub.2 rich bottom gas 104 is fed to the third reaction zone 130.

    [0313] The first liquid stream 119 is fed to the second reaction zone 120 and the third reaction zone 130 through the second set of liquid port 112, as the H.sub.2 rich quench liquids 103.

    [0314] Thus, in this embodiment, the first reaction zone 110 is fed with the H.sub.2 poor quench liquid 101 and the H.sub.2 poor bottom gas 102. The terpolymer prepared in this first reaction zone 110 has a high molecular weight.

    [0315] The third reaction zone 130 is fed with the H.sub.2 rich quench liquid 103 and the H.sub.2 rich bottom gas 104. The terpolymer prepared in this first reaction zone 110 has a low molecular weight.

    [0316] The second reaction zone 120 is fed with the H.sub.2 rich quench liquid 103 and the H.sub.2 poor bottom gas 102. The terpolymer prepared in this second reaction zone 120 has a molecular weight between those made in the first and the third reaction zones 110, 130.

    [0317] Since fresh ethylene is fed directly to the first reaction zone 110 and the second reaction zone 120 as part of the H.sub.2 poor bottom gas 102, the third reaction zone 130 receives ethylene only from the reactor off-gas.

    [0318] Since fresh 1-hexene is fed directly to the first reaction zone 110 as the H.sub.2 poor quench liquid 101, the second and the third reaction zones 120 and 130 receive 1-hexene only from the reactor off-gas. The concentration of 1-hexene in the first reaction zone 110 will be relatively high.

    Example 9

    [0319] Similar to FIG. 8, FIG. 10 shows a reactor 100 consisting of a first reaction zone 110, a second reaction zone 120 and a third reaction zone 130.

    [0320] In this embodiment, fresh propylene and ethylene are fed as part of the H.sub.2 poor bottom gas 102 to the first reaction zone 110 and the second reaction zone 120. Fresh propylene, 1-hexene and ethylene are fed as part of the as a part of the H.sub.2 poor quench liquid 101 to the first reaction zone 110.

    [0321] The separator 140 provides a first liquid stream 119 and a first gas stream 121. The first gas stream 121 is mixed with additional H.sub.2 and the obtained H.sub.2 rich bottom gas 104 is fed to the third reaction zone 130.

    [0322] The first liquid stream 119 is separated into a H.sub.2 rich quench liquid 103 fed to the second reaction zone 120, and to the third reaction zone 130 and a part 122 of the first liquid stream 119 is fed to a H.sub.2 stripper 160.

    [0323] H.sub.2 and some ethylene are removed from the part 122 of the first liquid stream 119 to form a second liquid stream 101 comprising propylene and 1-hexene and some ethylene which was not removed by the H.sub.2 stripper.

    [0324] The second liquid stream 101 is fed to the first reaction zone 110 as H.sub.2 poor quench liquid.

    [0325] Since fresh ethylene is fed directly to first and second reaction zone via the H.sub.2 poor bottom gas 102, the third reaction zone 130 receives ethylene only from the reactor off-gas.

    [0326] Since fresh 1-hexene is fed to the first reaction zone 110. The 1-hexene concentration would be high in the first reaction zone and lower in the other.

    Example 10

    [0327] In another non-limitative embodiment shown by FIG. 10, a schematic representation of a non-limiting example of a system for carrying out the process of the invention, in which the two other distinct monomers chosen from a group comprising ethylene and C4-C12 α-olefin are ethylene and 1-hexene: [0328] fresh ethylene and 1-hexene are fed to the reactor by feeding through the separator 140, [0329] a part 122 of the first liquid stream 119 is fed to a H.sub.2 stripper 160 to remove H.sub.2 and some ethylene to form a second liquid stream comprising propylene and 1-hexene and some ethylene which was not removed by the H.sub.2 stripper and [0330] the second liquid stream is fed to the reactor as a part of the H.sub.2 poor quench liquid 101.

    [0331] In this embodiment, the 1-hexene concentration and the ethylene concentration in the high molecular weight terpolymer (low H.sub.2 concentration zone) would be generally lower than in the embodiment of FIG. 9, provided that other process parameters are the same.

    [0332] Similar to FIGS. 8 and 9, FIG. 10 shows a reactor 100 consisting of a first reaction zone 110, a second reaction zone 120 and a third reaction zone 130.

    [0333] In this embodiment, fresh propylene is fed as part of the H.sub.2 poor bottom gas 102 to the first reaction zone 110 and the second reaction zone 120 through a first set of gas port 114.

    [0334] Fresh propylene, 1-hexene and ethylene are fed to a separator 140.

    [0335] The separator 140 provides a first liquid stream 119 and a first gas stream 121.

    [0336] The first liquid stream 119 comprises essentially the fresh propylene and the fresh 1-hexene added to the separator.

    [0337] The first gas stream 121 comprises essentially the fresh ethylene added to the separator. The first gas stream 121 is mixed with additional H.sub.2 and the obtained H.sub.2 rich bottom gas 104 is fed to the third reaction zone 130 through the second set of gas port 115.

    [0338] The first liquid stream 119 is separated into a H.sub.2 rich quench liquid 103 fed to the second reaction zone 120, and to the third reaction zone 130.

    [0339] A part 122 of the first liquid stream 119 is fed to a H.sub.2 stripper 160, where most part of H.sub.2 and some ethylene are removed and fed to the condenser 150 through a rich H.sub.2 line.

    [0340] The stripper form a second liquid stream comprising essentially propylene and 1-hexene and some ethylene which was not removed by the H.sub.2 stripper. The second liquid stream is fed to the first reaction zone 110 as a part of the H.sub.2 poor quench liquid 101.

    [0341] Since fresh ethylene is fed directly to the separator 140, the third reaction zone 130 receives ethylene via the H.sub.2 rich bottom gas 104 and the concentration of ethylene in the third reaction 130 will be relatively high.

    [0342] In contrast, the first and the second reaction zones 110, 120 receive ethylene only from the H.sub.2 poor quench liquid 101 and the H.sub.2 rich quench liquid 103, respectively. The concentration of ethylene in the second reaction zone 120 will be lower than in the third reaction zone 130 and the in the first reaction zone 110 will even lower than in the second reaction zone 120.

    [0343] Since fresh 1-hexene is fed to the separator 140, the first reaction zone 110 receives 1-hexene only as part of the H.sub.2 poor quench liquid 101. The 1-hexene concentration would be relatively flat over the reactor.

    Example 11

    [0344] In another non-limitative embodiment shown by FIG. 11, a schematic representation of a non-limiting example of a system for carrying out the process of the invention, similar to the one describe in FIG. 9 or 10, in which the two other distinct monomers chosen from a group comprising ethylene and C4-C12 α-olefin are 1-butylene and 1-hexene: [0345] fresh 1-butylene and 1-hexene and a part of the fresh propylene are fed to the reactor through the first liquid stream 119 from the separator 140, [0346] a part of fresh propylene is fed to the reactor as a part of the H.sub.2 poor bottom gas 102.

    Example 12

    [0347] As show by the FIGS. 12a and 12b, the profile of the terpolymer obtain following a stat of the art process comprising 2 separate reactors and a process according to the invention are very different.

    [0348] In particular, in the state of the art system the profile is a step curve, while in the system of the invention the profile is more a damped curve.

    [0349] Therefore, the process according to the invention allows the production of new kind of propylene-based terpolymer having properties suitable for new and old applications, that none of the processes described in the stat of the art can produce.

    LIST OF REFERENCE SIGNS

    [0350] 100 an horizontal stirred reactor [0351] 101 H.sub.2 poor quench liquid [0352] 102 H.sub.2 poor bottom gas [0353] 103 H.sub.2 rich quench liquid [0354] 104 H.sub.2 rich bottom gas [0355] 110 a first reaction zone [0356] 111 a first set of the liquid feed ports [0357] 112 second set of the liquid feed ports [0358] 114 a first set of gas feed ports [0359] 115 a second set of gas feed ports [0360] 116 off-gas ports [0361] 117 a reactor off-gas [0362] 118 a gas liquid mixture line [0363] 119 a first liquid stream line [0364] 120 a second reaction zone [0365] 121 a first gas stream [0366] 122 a part of the first liquid stream 119 [0367] 123 a rich H.sub.2 line [0368] 130 a third reaction zone [0369] 140 a separator [0370] 150 a condenser [0371] 160 a stripper column [0372] 116 off-gas ports