Separation method of solution polymerization reaction product

Abstract

The invention belongs to the field of material synthesis, and discloses a separation method of a solution polymerization reaction product to solve the problem of high energy consumption of traditional sequential separation, including rectification path separation or dividing wall column integrated separation. The rectification path separation comprises solvent pre-separation or 1-octene pre-separation, and the separation scheme of the solvent pre-separation comprises a solvent pre-separation tower, a C6 separation tower, a 1-hexene separation tower, a solvent separation tower and a 1-octene light separation tower; the separation scheme of 1-octylene pre-separation comprises a 1-octylene pre-separation tower, a 1-octylene heavy separation tower, a C6 separation tower, a 1-hexene separation tower and a heavy component removal tower. The separation product comprises a C6 by-product, 1-hexene, 1-octene, a circulating solvent and a heavy component, and the C6 by-product comprises methyl cyclopentane and methylene cyclopentane; and the circulating solvent is further purified through the amino-functionalized adsorption material. The method breaks through the fixed separation sequence, reduces the energy consumption, improves the solvent recovery rate and purity, and is suitable for industrial production.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of material synthesis, and particularly relates to a separation method of a solution polymerization reaction product. BACKGROUND

[0002] Solution polymerization technology is one of the core methods for preparing polyolefins, synthetic rubber and other polymer materials. The reaction product system thereof is extremely complex, and contains not only alpha-olefin components such as methylcyclopentane, methylenecyclopentane, 1-hexene and 1-octene, but also cyclic solvents such as methylcyclohexane, n-hexane and n-heptane, and C10 and above heavy components.

[0003] The current industry generally adopts a fixed sequence separation scheme to process the solution polymerization reaction product, and the separation of alpha-olefins is required. The scheme is based on the difference in boiling point of components, and follows the separation path of low-boiling-point alpha-olefins, medium-boiling-point alpha-olefins, cyclic solvents, high-boiling-point alpha-olefins and heavy components: first, methylcyclopentane and methylenecyclopentane need to be separated at low temperature to avoid excessive volatilization in subsequent high-temperature operation; then 1-hexene is separated to prevent it from mixing with the cyclic solvent; then the cyclic solvent is recovered by increasing the temperature; finally, 1-octene is purified and the heavy components are treated.

[0004] However, this fixed sequence separation scheme has significant technical shortcomings, and the problem of high energy consumption is particularly prominent. On the one hand, each separation tower needs to be strictly adapted to the current separation component characteristics, resulting in frequent adjustment of operating parameters: the temperature needs to be maintained at a low level when separating methylcyclopentane and methylenecyclopentane, and the temperature needs to be gradually increased when separating 1-octene and heavy components, resulting in huge energy loss during repeated temperature rising and falling of the tower body; and in order to avoid the entrainment of previous components affecting subsequent separation, each tower needs to maintain a high reflux ratio, and the reflux ratio of some towers even exceeds 5, greatly increasing steam and power consumption. On the other hand, the series connection of sequential separation aggravates the energy consumption burden. If the target component is not completely separated in the previous tower, the subsequent tower needs to compensate by increasing the operating temperature or prolonging the separation time, further increasing the energy consumption.

[0005] With the development of green chemical industry and cost reduction and efficiency improvement as the mainstream of the industry, the defects of the traditional sequential separation scheme such as high energy consumption and limited purification effect are becoming increasingly prominent, and the industry urgently needs a solution polymerization reaction product separation method that breaks the limitation of fixed separation sequence, optimizes the component separation logic to reduce energy consumption, and has high purification capacity. SUMMARY

[0006] The application aims to provide a solution polymerization product separation method with low energy consumption and high efficiency of recycling solvent purification.

[0007] The technical scheme adopted by the application to achieve the above-mentioned purpose is as follows: The application discloses a solution polymerization product separation method, which comprises a distillation path separation or a dividing wall column integrated separation.

[0008] Preferably, the separation scheme of the solvent pre-separation comprises a solvent pre-separation tower, a C6 separation tower, a 1-hexene separation tower, a solvent separation tower and a 1-octene light separation tower.

[0009] Preferably, the separation scheme of the 1-octene pre-separation comprises a 1-octene pre-separation tower, a 1-octene heavy separation tower, a C6 separation tower, a 1-hexene separation tower and a heavy component removal tower.

[0010] Preferably, the separation products of the separation method comprise C6 by-products, 1-hexene, 1-octene, recycling solvent and heavy components.

[0011] Preferably, the C6 by-products comprise methylcyclopentane and methylenecyclopentane.

[0012] Preferably, in the solvent pre-separation, the operation temperature of the solvent pre-separation tower is 100-200 DEG C, and the operation pressure is 0-0.2 MPaG.

[0013] Preferably, in the solvent pre-separation, the operation temperature of the C6 separation tower is 70-170 DEG C, and the operation pressure is 0-0.2 MPaG.

[0014] Preferably, in the solvent pre-separation, the operation temperature of the 1-hexene separation tower is 60-130 DEG C, and the operation pressure is 0-0.2 MPaG.

[0015] Preferably, in the solvent pre-separation, the operation temperature of the solvent separation tower is 110-200 DEG C, and the operation pressure is 0.1-0.3 MPaG.

[0016] Preferably, in the solvent pre-separation, the operation temperature of the 1-octene light separation tower is 80-210 DEG C, and the operation pressure is-0.1-0.1 MPaG.

[0017] Preferably, in the solvent pre-separation, the solvent pre-separation column is operated at a temperature of 120-220°C and a pressure of 0.1-0.3 MPaG.

[0018] Preferably, in the 1-octene pre-separation, the 1-octene pre-separation column is operated at a temperature of 120-220°C and a pressure of 0.1-0.3 MPaG.

[0019] Preferably, in the 1-octene pre-separation, the 1-octene pre-separation column is operated at a temperature of 120-220°C and a pressure of 0.1-0.3 MPaG.

[0020] Preferably, in the 1-octene pre-separation, the C6 separation column is operated at a temperature of 70-170°C and a pressure of 0-0.2 MPaG.

[0021] Preferably, in the 1-octene pre-separation, the 1-hexene separation column is operated at a temperature of 60-130°C and a pressure of 0-0.2 MPaG.

[0022] Preferably, in the 1-octene pre-separation, the heavy-removal column is operated at a temperature of 80-210°C and a pressure of -0.1-0.1 MPaG.

[0023] Preferably, in the 1-octene pre-separation, the 1-octene pre-separation column is operated at a temperature of 120-220°C and a pressure of 0.1-0.3 MPaG.

[0024] Preferably, in the solvent pre-separation, the solvent pre-separation column is operated at a temperature of 120-220°C and a pressure of 0.1-0.3 MPaG.

[0025] Preferably, in the solvent pre-separation, the overhead stream enters the 1-hexene separation column, the overhead of which is separated to obtain the C6 component, and the bottom of which is separated to obtain the circulating solvent.

[0026] Preferably, in the solvent pre-separation, the C6 component enters the C6 separation column, the overhead of which is separated to obtain the 1-hexene, and the bottom of which is separated to obtain the C6 by-product, which includes methylcyclopentane and methylenecyclopentane.

[0027] Preferably, in the solvent pre-separation, the bottom stream enters the solvent separation column, the overhead of which is separated to obtain the circulating solvent, and the bottom of which is separated to obtain the intermediate component.

[0028] Preferably, in the solvent pre-separation, the intermediate component enters the 1-octene light separation column, the overhead of which is separated to obtain 1-octene, and the bottom of which is separated to obtain heavy component.

[0029] Preferably, in the 1-octene pre-separation, the overhead of the 1-octene pre-separation column is separated to obtain pre-separation overhead stream, and the bottom of which is separated to obtain bottom stream.

[0030] Preferably, in the 1-octene pre-separation, the pre-separation overhead stream enters the 1-octene heavy separation column, the overhead of which is separated to obtain heavy separation overhead stream, and the bottom of which is separated to obtain 1-octene.

[0031] Preferably, in the 1-octene pre-separation, the heavy separation overhead stream enters the 1-hexene separation column, the overhead of which is separated to obtain C6 component, and the bottom of which is separated to obtain circulating solvent.

[0032] Preferably, in the 1-octene pre-separation, the C6 component enters the C6 separation column, the overhead of which is separated to obtain 1-hexene, and the bottom of which is separated to obtain C6 by-product, which includes methylcyclopentane and methylenecyclopentane.

[0033] Preferably, in the 1-octene pre-separation, the bottom stream enters the heavy-removal column, the overhead of which is separated to obtain 1-octene, and the bottom of which is separated to obtain heavy component.

[0034] Preferably, in the single-separation-wall column separation, the overhead of the single-separation-wall column is separated to obtain 1-hexene, the side product is separated to obtain C6 by-product, and the bottom of which is separated to obtain solvent.

[0035] Preferably, in the single-separation-wall column separation, the rectification temperature of the single-separation-wall column is 50-250°C, and the operating pressure is 0-0.3MpaG.

[0036] Preferably, in the single-separation-wall column separation, the C6 by-product includes methylcyclopentane and methylenecyclopentane.

[0037] Preferably, in the double-separation-wall column separation, the separation column of the double-separation-wall column includes separation-wall column one and separation-wall column two.

[0038] Preferably, in the double-separation-wall column separation, the side product of the separation-wall column one is separated to obtain 1-octene, the bottom of which is separated to obtain heavy component, the overhead of which is separated to obtain 1-hexene, C6 by-product and solvent, which are fed to the separation-wall column two.

[0039] Preferably, in the double-separation-wall column separation, the overhead of the separation-wall column two is separated to obtain 1-hexene, the side product is separated to obtain C6 by-product, and the bottom of which is separated to obtain solvent.

[0040] Preferably, in the double-separation-wall column separation, the rectification temperature of the separation-wall column one is 50-300°C, and the operating pressure is -0.1-0.3MpaG.

[0041] Preferably, in the double-dividing wall column separation, the distillation temperature of the second dividing wall column is 50-250℃, and the operating pressure is 0.01-0.3 MPaG.

[0042] Preferably, in the double-dividing wall column separation, the C6 byproduct includes methylcyclopentane and methylenecyclopentane.

[0043] Preferably, the catalyst for solution polymerization includes a ligand a, a transition metal compound b, and an activator c.

[0044] Preferably, the ligand a includes a PNP ligand, a PNNP ligand, and a rigid linker.

[0045] Preferably, the transition metal compound b is a metal compound of Groups IVB-VIII.

[0046] Preferably, the activator c is a compound containing a Group IIIA metal.

[0047] Preferably, the circulating solvent is purified by an amino-functionalized adsorption material to obtain a purified circulating solvent.

[0048] Preferably, the core layer of the amino-functionalized adsorption material includes graphene oxide.

[0049] Preferably, the shell layer of the amino-functionalized adsorption material is formed by grafting a modifier via a crosslinking agent.

[0050] Preferably, the modifier includes 3,4-dihydroxyphenylacetamide and N-isopropyl-1,3-diaminopropane.

[0051] Preferably, the mass ratio of graphene oxide to 3,4-dihydroxyphenylacetamide is 2:0.5-3.

[0052] Preferably, the mass ratio of 3,4-dihydroxyphenylacetamide to N-isopropyl-1,3-diaminopropane is 2:0.5-5. 3,4-dihydroxyphenylacetamide and N-isopropyl-1,3-diaminopropane together construct an efficient adsorption system. 3,4-dihydroxyphenylacetamide forms hydrogen bonds and covalent bonds with oxygen-containing groups on the surface of graphene oxide through the hydroxyl groups in the molecule, realizes the tight coating of graphene oxide, optimizes the matrix structure, avoids the agglomeration of graphene oxide, provides stable attachment sites for subsequent functionalization modification, adjusts the dispersibility of the material in the circulating solvent system, and ensures the full exposure of the adsorption sites; N-isopropyl-1,3-diaminopropane is grafted to the surface of the coated graphene under the crosslinking action of glutaraldehyde, and the amino groups in the molecule can be used as specific adsorption sites to combine with residual catalyst transition metal ions through coordination, further enhancing the selective adsorption capacity of trace impurities, and finally realizing the deep purification of the circulating solvent.

[0053] More preferably, the modifier comprises N-vinyl-N-methylacetamide, and the mass ratio of 3,4-dihydroxyphenylacetamide to N-vinyl-N-methylacetamide is 2:0.5-5. N-vinyl-N-methylacetamide can assist in anchoring N-isopropyl-1,3-diaminopropane on one hand, and enhance the grafting stability of N-isopropyl-1,3-diaminopropane on the surface of graphene, avoiding the loss of functional groups; on the other hand, N-vinyl-N-methylacetamide introduces additional nitrogen-containing functional groups, which cooperates with the amino groups of N-isopropyl-1,3-diaminopropane to construct more intensive specific adsorption sites, and the capture capacity of transition metal ions of the catalyst residues in the circulating solvent is strengthened through coordination; the dispersibility of the material in the circulating solvent dispersion liquid is optimized, ensuring that the adsorption sites are fully exposed and efficiently contact with impurities, thereby improving the removal efficiency of trace impurities by the adsorption material.

[0054] The application also provides a preparation method of a refined reaction raw material, comprising: The reaction raw material comprises a solvent and ethylene, fresh ethylene is transported into the zone from the pipeline outside the zone, heated to 85-95℃, deoxidized from top to bottom into an ethylene deoxidizer, and then deoxidized from top to bottom into an ethylene-carbon monoxide removal tower, and then cooled to 30-40℃ in an ethylene cooler, and then dehydrated from top to bottom into an ethylene drying / carbon dioxide removal device, to remove water and carbon dioxide in the ethylene, to obtain refined ethylene; fresh solvent is transported into the zone from the pipeline outside the zone, and a large amount of water in the solvent is removed through a crude solvent coalescer, and then transported to a solvent degassing tower for light component removal, and the liquid in the tower is cooled to 30-40℃ in a solvent cooler, and then transported from bottom to top into a solvent dryer to remove water, and then transported from bottom to top into a solvent guard bed to remove other polar substances in the solvent, and then filtered through a solvent filter, to obtain refined solvent.

[0055] Preferably, the solvent is one or more of methylcyclohexane, n-hexane and n-heptane.

[0056] The application also provides a preparation method of a catalyst solution, comprising: The catalyst is added into the refined solvent, stirred at 35-45℃ and 150-250rpm for 20-40min, to obtain the catalyst solution. The catalyst comprises a ligand a, a transition metal compound b and an activator c.

[0057] Preferably, the ligand a comprises a PNP ligand, a PNNP ligand and a rigid linker.

[0058] More preferably, the ligand a is 1,4-phenylene bis(diphenylphosphinomethylamine).

[0059] Preferably, the transition metal compound b is a metal compound of groups IVB-VIII.

[0060] More preferably, the transition metal compound b is zirconium tetrachloride.

[0061] Preferably, the activator c is a compound containing a Group IIIA metal.

[0062] More preferably, the activator c is methylaluminoxane.

[0063] Preferably, the molar ratio of the ligand a to the transition metal compound b is 1:0.1-100.

[0064] More preferably, the molar ratio of the ligand a to the transition metal compound b is 1:0.1-1.

[0065] Preferably, the molar ratio of the ligand a to the activator c is 1:0.1-5000.

[0066] More preferably, the molar ratio of the ligand a to the activator c is 1:0.1-1000.

[0067] Further preferably, the molar ratio of the ligand a to the activator c is 1:0.1-500.

[0068] Preferably, the mass of the catalyst is measured by the mass of the ligand a therein, and the mass volume ratio of the ligand a to the refined solvent is 10-30 g:1 L.

[0069] The present application also provides a method for preparing a reaction product, comprising: The refined ethylene is pressurized to 2.5-6.5 MPaG by a fresh ethylene compressor and delivered into a reaction unit reactor, the refined solvent is pressurized to 2.5-6.5 MPaG by a pump and delivered into the reaction unit reactor, and the hydrogen is pressurized to 2.5-6.5 MPaG by a hydrogen compressor and delivered into the reaction unit reactor, which are mixed and then enter a reactor feed cooler, cooled and controlled to an outlet temperature of -10-40℃, and then enter a first reactor; the catalyst solution is pressurized to 2.5-6.5 MPaG by a pump and delivered into the first reactor, and is kept in the reactor at 2.5-6.5 MPaG and 35-120℃ for 20-60 min, and then delivered into a termination kettle, a termination agent is added, the reaction is terminated, and a reaction product is obtained.

[0070] Preferably, the volume ratio of the refined solvent to the refined ethylene is 2 L:0.5-2 mL. 3 .

[0071] Preferably, the volume ratio of the refined solvent to the catalyst solution is 2 L:0.5-2 mL.

[0072] Preferably, the termination agent is isooctanol.

[0073] Preferably, the volume ratio of the refined solvent to the termination agent is 2 L:0.5-2 mL.

[0074] The present application also provides a method for preparing a flash stream, comprising: Preparation of the flash stream: multi-stage flash distillation of the reaction product at 100-160°C and 0.04-3 MPaG to obtain the flash stream.

[0075] Preferably, the flash stream comprises recycled ethylene and product components.

[0076] The present application also provides a method for separating product components, comprising: The product components are fed into a solvent pre-separation column, overhead separation to obtain an overhead stream, and bottom separation to obtain a bottom stream; the overhead stream is fed into a 1-hexene separation column, overhead separation to obtain a C6 component, and bottom separation to obtain recycled solvent; the C6 component is fed into a C6 separation column, overhead separation to obtain 1-hexene, and bottom separation to obtain a C6 byproduct comprising methylcyclopentane and methylenecyclopentane; the bottom stream is fed into a solvent separation column, overhead separation to obtain recycled solvent, and bottom separation to obtain an intermediate component; the intermediate component is fed into a 1-octene light separation column, overhead separation to obtain 1-octene, and bottom separation to obtain a heavy component. Preferably, the solvent pre-separation column is operated at a temperature of 100-200°C and a pressure of 0-0.2 MPaG.

[0077] Preferably, the C6 separation column is operated at a temperature of 70-170°C and a pressure of 0-0.2 MPaG.

[0078] Preferably, the 1-hexene separation column is operated at a temperature of 60-130°C and a pressure of 0-0.2 MPaG.

[0079] Preferably, the solvent separation column is operated at a temperature of 110-200°C and a pressure of 0.1-0.3 MPaG.

[0080] Preferably, the 1-octene light separation column is operated at a temperature of 80-210°C and a pressure of -0.1-0.1 MPaG.

[0081] Preferably, the overhead stream of the solvent pre-separation column comprises more than 99 wt% of the C6 component and lighter components C6- in the feed, and 10-90% of the total solvent components in the feed, and the bottom stream comprises the remaining solvent components after the overhead stream is taken out, and more than 99 wt% of the C8 component and heavier components C8+ in the feed.

[0082] The present application also provides a method for separating product components, comprising: The product components enter a 1-octene pre-separation column, the overhead of which is separated to obtain a pre-separation overhead stream, and the bottom of which is separated to obtain a column bottom stream; the pre-separation overhead stream enters a 1-octene re-separation column, the overhead of which is separated to obtain a re-separation overhead stream, and the bottom of which is separated to obtain 1-octene; the re-separation overhead stream enters a 1-hexene separation column, the overhead of which is separated to obtain a C6 component, and the bottom of which is separated to obtain a circulating solvent; the C6 component enters a C6 separation column, the overhead of which is separated to obtain 1-hexene, and the bottom of which is separated to obtain a C6 by-product, which includes methylcyclopentane and methylenecyclopentane; and the column bottom stream enters a heavy component removal column, the overhead of which is separated to obtain 1-octene, and the bottom of which is separated to obtain a heavy component.

[0083] Preferably, the 1-octene pre-separation column is operated at a temperature of 120-220°C and a pressure of 0.1-0.3 MPaG.

[0084] Preferably, the 1-octene re-separation column is operated at a temperature of 100-190°C and a pressure of 0.1-0.3 MPaG.

[0085] Preferably, the C6 separation column is operated at a temperature of 70-170°C and a pressure of 0-0.2 MPaG.

[0086] Preferably, the 1-hexene separation column is operated at a temperature of 60-130°C and a pressure of 0-0.2 MPaG.

[0087] Preferably, the heavy component removal column is operated at a temperature of 80-210°C and a pressure of -0.1-0.1 MPaG.

[0088] Preferably, the stream taken from the overhead of the 1-octene pre-separation column contains 99 wt% of the solvent in the feed, the C6 component and lighter components C6-, and 80% of the total C8 components in the feed, and the stream taken from the bottom of the column contains the C8 components remaining after the overhead stream is taken, and 99 wt% of the C10 and heavier components C10+ in the feed. The column bottom The present application also provides a method for separating product components, comprising: The product components enter a single-wall column, the overhead of which is separated to obtain C6 straight-chain α-olefins, the first side is separated to obtain a C6 by-product of α-olefins, and the bottom is separated to obtain a circulating solvent.

[0089] Preferably, the single-wall column is operated at a distillation temperature of 50-250°C and a pressure of 0.01-0.3 MPaG.

[0090] Preferably, the C6 straight-chain α-olefins are 1-hexene.

[0091] Preferably, the C6 by-product is one or more of methylcyclopentane, methylenecyclopentane and internal olefins.

[0092] The application further provides a product component separation method, comprising: The product component enters the dividing wall column I, C6 linear alpha-olefins are separated from the top of the dividing wall column I, alpha-olefin C6 byproducts are separated from the first side of the dividing wall column I, solvents are separated from the bottom of the dividing wall column I, the product flows to the dividing wall column II, C8 linear alpha-olefins are separated from the first side of the dividing wall column I, C10 and above linear alpha-olefins are separated from the bottom of the dividing wall column I; C6 linear alpha-olefins are separated from the top of the dividing wall column II, alpha-olefin C6 byproducts are separated from the first side of the dividing wall column II, solvents are separated from the bottom of the dividing wall column II.

[0093] Preferably, the rectification temperature of the dividing wall column I is 50-300 DEG C, and the operation pressure is -0.1-0.3 Mpa G.

[0094] Preferably, the rectification temperature of the dividing wall column II is 50-250 DEG C, and the operation pressure is 0.01-0.3 Mpa G.

[0095] Preferably, the C6 linear alpha-olefins are 1-hexene.

[0096] Preferably, the C6 byproducts are methylcyclopentane, methylene cyclopentane and internal olefins.

[0097] Preferably, the C8 linear alpha-olefins are 1-octene.

[0098] The application further provides a preparation method of an amino-functionalized adsorptive material, comprising: The graphene oxide is dispersed in a Tris-hydrochloric acid buffer solution with a pH of 8.3-8.7, ultrasonically treated for 1-3 h, 3,4-dihydroxyphenylacetamide is added, stirred at 25-35 DEG C for 20-30 h, centrifuged at 7000-9000 rpm for 5-15 min, washed with deionized water, and freeze-dried at minus 45-55 DEG C for 40-50 h to obtain coated graphene; glutaraldehyde is dissolved in deionized water to obtain a glutaraldehyde solution; the coated graphene is dispersed in deionized water to obtain a coated graphene dispersion, the glutaraldehyde solution is added, stirred at room temperature for 20-40 min, N-isopropyl-1,3-diaminopropane is added, stirred at room temperature for 10-20 h, centrifuged at 7000-9000 rpm for 5-15 min, washed with deionized water, and freeze-dried at minus 45-55 DEG C for 40-50 h to obtain the amino-functionalized adsorptive material.

[0099] Preferably, the mass-volume ratio of the graphene oxide to the Tris-hydrochloric acid buffer solution is 2 mg:0.5-2 mL.

[0100] Preferably, the mass ratio of the graphene oxide to the 3,4-dihydroxyphenylacetamide is 2:0.5-3.

[0101] Preferably, the mass-volume ratio of glutaraldehyde to deionized water in the glutaraldehyde solution is 1:1-5.

[0102] Preferably, the mass-volume ratio of coated graphene to deionized water in the coated graphene dispersion solution is 3mg:1-5mL.

[0103] Preferably, the mass of the glutaraldehyde solution is measured by the mass of glutaraldehyde therein, and the mass of the coated graphene is measured by the mass of 3,4-dihydroxyphenylacetamide therein, and the mass ratio of 3,4-dihydroxyphenylacetamide to glutaraldehyde is 1:3-10.

[0104] Preferably, the mass of the coated graphene is measured by the mass of 3,4-dihydroxyphenylacetamide therein, and the mass ratio of 3,4-dihydroxyphenylacetamide to N-isopropyl-1,3-diaminopropane is 2:3-10.

[0105] More preferably, the coated graphene dispersion solution can further add N-vinyl-N-methylacetamide.

[0106] More preferably, the mass of the coated graphene is measured by the mass of 3,4-dihydroxyphenylacetamide therein, and the mass ratio of 3,4-dihydroxyphenylacetamide to N-vinyl-N-methylacetamide is 2:0.5-5.

[0107] The application also provides a preparation method of a purified circulating solvent, comprising: The separated circulating solvent is dispersed in deionized water to obtain a circulating solvent dispersion solution, and an amino-functionalized adsorption material is added, and stirred at 35-45℃ and 100-300rpm for 5-10h, and centrifuged at 7000-9000rpm for 5-15min, and the upper liquid is collected, washed with deionized water, dried with anhydrous magnesium sulfate, and filtered to obtain a purified circulating solvent.

[0108] Preferably, the volume ratio of circulating solvent to deionized water in the circulating solvent dispersion solution is 3:3-10.

[0109] Preferably, the volume-mass ratio of the circulating solvent to the amino-functionalized adsorption material is 1mL:0.1-0.5mg.

[0110] Preferably, the volume-mass ratio of the circulating solvent to the anhydrous magnesium sulfate is 1mL:1-5mg.

[0111] The present application has the following beneficial effects: breaking through the high energy consumption bottleneck of traditional fixed sequence separation, reducing energy loss caused by repeated temperature rise and fall of column body and high reflux ratio, and significantly improving the recovery rate of circulating solvent; the amino-functionalized adsorption material can efficiently remove catalyst residue impurities through the coordination of amino group and transition metal ions, and the method process is stable and controllable, and is suitable for industrial continuous production. Therefore, the present application is a solution polymerization reaction product separation method with low energy consumption, high purification efficiency and clear industrial application value. BRIEF DESCRIPTION OF DRAWINGS

[0112] Figure 1 The flowchart of Example 1 is shown.

[0113] Figure 2 The separation unit flowchart of Example 1 is shown.

[0114] Figure 3 The separation unit flowchart of Example 2 is shown.

[0115] Figure 4 The separation unit flowchart of Example 3 is shown.

[0116] Figure 5 The separation unit flowchart of Example 4 is shown.

[0117] Figure 6 The separation unit flowchart of Comparative Example 1 is shown. DETAILED DESCRIPTION

[0118] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0119] The concepts involved in the present application will be described below in combination with the drawings. It should be pointed out here that the following descriptions of the concepts are only to make the content of the present application easier to understand, and do not represent a limitation on the scope of protection of the present application; meanwhile, the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0120] Example 1: The flowchart of Example 1 is shown in Figure 1 The separation method of the solution polymerization reaction product includes a refining unit, a reaction unit, a flash evaporation unit and a separation unit.

[0121] The separation method of the solution polymerization reaction product comprises: passing the reaction raw material through a refining unit to perform purification treatment, to prepare a refined reaction raw material; passing the refined reaction raw material and the catalyst solution through a reaction unit to perform polymerization reaction, to prepare a reaction product; passing the reaction product through a flash evaporation unit to perform flash evaporation separation to obtain a flash evaporation stream, the flash evaporation stream comprising a circulating solvent and a product component; passing the product component into a separation unit to separate to obtain different components.

[0122] The separation unit flow diagram of Example 1 is shown in Figure 2 The separation unit comprises a solvent pre-separation tower, a 1-hexene separation tower, a C6 separation tower, a solvent separation tower and a 1-octene light separation tower.

[0123] Preparation of the refined reaction raw material: the reaction raw material comprises a solvent and ethylene, fresh ethylene is transported from the pipeline outside the boundary into the boundary, heated to 90℃, deoxidized from top to bottom into the ethylene deoxidizer, then deoxidized from top to bottom into the ethylene carbon monoxide removal tower to remove carbon monoxide, then cooled to 40℃ by the ethylene cooler, then dehydrated and deoxidized by the ethylene drying / decarbonation device to remove water and carbon dioxide in the ethylene, to obtain refined ethylene; fresh solvent is transported from the pipeline outside the boundary into the boundary, dehydrated by the crude solvent coalescer to remove a large amount of water in the solvent, transported to the solvent degassing tower to remove light components, the tower bottom liquid is cooled to 40℃ by the solvent cooler, the solvent is transported from bottom to top to the solvent dryer to remove water, after drying, the solvent is transported from bottom to top into the solvent guard bed to remove other polar substances in the solvent, filtered by the solvent filter, to obtain refined solvent. The solvent is n-hexane.

[0124] Preparation of the catalyst solution: the catalyst is added to the refined solvent, stirred at 40℃ and 200rpm for 30min, to obtain the catalyst solution. The catalyst comprises ligand a, transition metal compound b and activator c, the ligand a is 1,4-phenylene bis(diphenylphosphinylmethylamine), the transition metal compound b is zirconium tetrachloride, and the activator c is methylaluminoxane; the molar ratio of the ligand a to the transition metal compound b is 2:1, and the molar ratio of the ligand a to the activator c is 1:100; the mass of the catalyst is measured by the mass of the ligand a therein, and the mass / volume ratio of the ligand a to the refined solvent is 20g:1L.

[0125] Preparation of reaction product: The refined ethylene is pressurized to 4.0 MPaG by a fresh ethylene compressor and sent to the reaction unit reactor. The refined solvent is pressurized to 4.0 MPaG by a pump and sent to the reaction unit reactor. The hydrogen is pressurized to 4.0 MPaG by a hydrogen compressor and sent to the reaction unit reactor. After mixing, the mixture enters the reactor feed cooler, which is cooled and controlled to an outlet temperature of 20°C, and then enters the first reactor. The catalyst solution is pressurized to 4.0 MPaG by a pump and sent to the first reactor. The mixture is kept in the reactor at 80°C and 4.0 MPaG for 40 minutes, then sent to the termination kettle, where a termination agent is added to terminate the reaction, and the reaction product is obtained. The volume ratio of the refined solvent to the refined ethylene is 2L: 1 mL, the volume ratio of the refined solvent to the catalyst solution is 2L: 1 mL, the termination agent is isooctanol, and the volume ratio of the refined solvent to the termination agent is 2L: 1 mL. 3 The preparation of the flash stream: The reaction product is multi-stage flashed at 130°C and 1.0 MPaG to obtain a flash stream, which includes recycled ethylene and a product component.

[0126] The preparation of the flash stream: The reaction product is multi-stage flashed at 130°C and 1.0 MPaG to obtain a flash stream, which includes recycled ethylene and a product component.

[0127] The separation of the product component: The product component enters the solvent pre-separation column, and the overhead stream is separated at the top of the column, and the column bottoms stream is separated at the bottom of the column. The overhead stream enters the 1-hexene separation column, and C6 components are separated at the top of the column, and recycled solvent is separated at the bottom of the column. The C6 components enter the C6 separation column, and 1-hexene is separated at the top of the column, and C6 byproducts, including methylcyclopentane and methylenecyclopentane, are separated at the bottom of the column. The column bottoms stream enters the solvent separation column, and recycled solvent is separated at the top of the column, and an intermediate component is separated at the bottom of the column. The intermediate component enters the 1-octene light separation column, and 1-octene is separated at the top of the column, and a heavy component is separated at the bottom of the column. The operating temperature of the solvent pre-separation column is 150°C, and the operating pressure is 0.1 MPaG. The operating temperature of the 1-hexene separation column is 120°C, and the operating pressure is 0.2 MPaG. The operating temperature of the C6 separation column is 105°C, and the operating pressure is 0.2 MPaG. The operating temperature of the solvent separation column is 180°C, and the operating pressure is 0.2 MPaG. The operating temperature of the 1-octene separation column is 190°C, and the operating pressure is 0.05 MPaG. The overhead stream of the solvent pre-separation column contains 99 wt% of the C6 components and lighter components C6- in the feed, and 80% of the total solvent components in the feed. The column bottoms stream contains the remaining solvent components after the overhead stream is taken out, and 99 wt% of the C8 components and heavier components C8+ in the feed.

[0128] Example 2: This example is different from Example 1 only in the separation of the product component.

[0129] The separation unit flow diagram of Example 2 is shown in FIG. 2. Figure 3As shown, the separation unit comprises a 1-octene pre-separation column, a 1-octene re-separation column, a hexene re-separation column and a heavy component removal column.

[0130] Separation of product components: the product components enter the 1-octene pre-separation column, the overhead of which is separated to obtain an overhead stream, and the bottom of which is separated to obtain a bottom stream; the overhead stream enters the 1-octene re-separation column, the overhead of which is separated to obtain an overhead stream, and the bottom of which is separated to obtain 1-octene; the overhead stream enters the 1-hexene separation column, the overhead of which is separated to obtain a C6 component, and the bottom of which is separated to obtain a circulating solvent; the C6 component enters the C6 separation column, the overhead of which is separated to obtain 1-hexene, and the bottom of which is separated to obtain a C6 by-product, which comprises methylcyclopentane and methylenecyclopentane; the bottom stream enters the heavy component removal column, the overhead of which is separated to obtain 1-octene, and the bottom of which is separated to obtain heavy components. The operating temperature of the 1-octene pre-separation column is 190°C, and the operating pressure is 0.2 MPaG; the operating temperature of the 1-octene separation column is 150°C, and the operating pressure is 0.2 MPaG; the operating temperature of the 1-hexene separation column is 120°C, and the operating pressure is 0.1 MPaG; the operating temperature of the C6 separation column is 105°C, and the operating pressure is 0.2 MPaG; the operating temperature of the heavy component removal column is 180°C, and the operating pressure is 0.1 MPaG; the overhead stream of the 1-octene pre-separation column comprises 99 wt% of the solvent in the feed, lighter components of the C6 component and C6-, and 80% of the total C8 components in the feed, and the bottom stream comprises the remaining C8 components after the overhead stream is taken out, 99 wt% of the C10 and heavier components C10+ in the feed.

[0131] Example 3: This example is different from Example 1 only in the separation of product components.

[0132] The separation unit flow diagram of Example 3 is shown in Figure 4 As shown, the separation unit comprises a single partition wall column.

[0133] Separation of product components: the product components enter the single partition wall column, the overhead of which is separated to obtain a C6 straight-chain α-olefin, the first side of which is separated to obtain a C6 by-product of α-olefin, and the bottom of which is separated to obtain a circulating solvent. The rectification temperature of the single partition wall column is 180°C, and the operating pressure is 0.1 MPaG; the C6 straight-chain α-olefin is 1-hexene, and the C6 by-product is methylcyclopentane and methylenecyclopentane.

[0134] Example 4: This example is different from Example 1 only in the separation of product components.

[0135] The separation unit flow diagram of Example 4 is shown in Figure 5 As shown, the separation unit comprises a double partition wall column, which comprises a partition wall column one and a partition wall column two.

[0136] Separation of product components: the product components enter the dividing wall column 1, the overhead of the dividing wall column 1 is separated to obtain C6 linear alpha-olefins, alpha-olefin C6 byproducts, solvents, the overhead stream flows to the dividing wall column 2, the first side of the dividing wall column 1 is separated to obtain C8 linear alpha-olefins, the bottom of the dividing wall column 1 is separated to obtain C10 and above linear alpha-olefins; the overhead of the dividing wall column 2 is separated to obtain C6 linear alpha-olefins, the first side of the dividing wall column 2 produces alpha-olefin C6 byproducts, the bottom of the dividing wall column 2 is separated to obtain solvents. The rectification temperature of the dividing wall column 1 is 250°C, and the operating pressure is 0.1 MPaG; the rectification temperature of the dividing wall column 2 is 180°C, and the operating pressure is 0.1 MPaG; the C6 linear alpha-olefins are 1-hexene, the C6 byproducts are methylcyclopentane and methylene cyclopentane; the C8 linear alpha-olefins are 1-octene.

[0137] Example 5: The difference between this example and Example 1 is that it further includes the preparation of purified circulating solvents.

[0138] Preparation of amino-functionalized adsorbent material: graphene oxide is dispersed in Tris-hydrochloric acid buffer solution with pH 8.5, ultrasonic for 2 h, 3,4-dihydroxyphenylacetamide is added, stirring at 30°C for 24 h, centrifugation at 8000 rpm for 10 min, washing with deionized water, and freeze-drying at minus 50°C for 48 h to obtain coated graphene; glutaraldehyde is dissolved in deionized water to obtain a glutaraldehyde solution; the coated graphene is dispersed in deionized water to obtain a coated graphene dispersion, the glutaraldehyde solution is added, stirring at room temperature for 30 min, N-isopropyl-1,3-diaminopropane is added, stirring at room temperature for 18 h, centrifugation at 8000 rpm for 10 min, washing with deionized water, and freeze-drying at minus 50°C for 48 h to obtain the amino-functionalized adsorbent material. The mass-volume ratio of graphene oxide to Tris-hydrochloric acid buffer solution is 2 mg:1 mL, and the mass ratio of graphene oxide to 3,4-dihydroxyphenylacetamide is 2:1; in the glutaraldehyde solution, the mass-volume ratio of glutaraldehyde to deionized water is 1:3; in the coated graphene dispersion, the mass-volume ratio of coated graphene to deionized water is 3 mg:2 mL; the mass of the glutaraldehyde solution is measured by the mass of glutaraldehyde therein, the mass of the coated graphene is measured by the mass of 3,4-dihydroxyphenylacetamide therein, the mass ratio of 3,4-dihydroxyphenylacetamide to glutaraldehyde is 1:5, and the mass ratio of 3,4-dihydroxyphenylacetamide to N-isopropyl-1,3-diaminopropane is 2:5.

[0139] Preparation of the purified circulating solvent: the separated circulating solvent was dispersed in deionized water to obtain a circulating solvent dispersion liquid, and an amino-functionalized adsorption material was added. The mixture was stirred at 40°C and 200 rpm for 8 h, centrifuged at 8000 rpm for 10 min, and the upper liquid was collected. The collected liquid was washed with deionized water, dried with anhydrous magnesium sulfate, filtered, and then the purified circulating solvent was obtained. In the circulating solvent dispersion liquid, the volume ratio of the circulating solvent to deionized water was 3:5; the volume-mass ratio of the circulating solvent to the amino-functionalized adsorption material was 1 mL:0.3 mg; and the volume-mass ratio of the circulating solvent to the anhydrous magnesium sulfate was 1 mL:2 mg.

[0140] Example 6: The difference between this example and Example 5 is only in the preparation of the amino-functionalized adsorption material.

[0141] Preparation of the amino-functionalized adsorption material: graphene oxide was dispersed in a Tris-hydrochloric acid buffer solution with a pH of 8.5, and ultrasonic treatment was performed for 2 h. Then, 3,4-dihydroxyphenylacetamide was added, and the mixture was stirred at 30°C for 24 h. After centrifugation at 8000 rpm for 10 min, the product was washed with deionized water and freeze-dried at -50°C for 48 h to obtain coated graphene. Glutaraldehyde was dissolved in deionized water to obtain a glutaraldehyde solution. The coated graphene was dispersed in deionized water to obtain a coated graphene dispersion liquid, and the glutaraldehyde solution was added. The mixture was stirred at room temperature for 30 min, and then N-isopropyl-1,3-diaminopropane was added. The mixture was stirred at room temperature for 18 h, centrifuged at 8000 rpm for 10 min, washed with deionized water, and freeze-dried at -50°C for 48 h to obtain the amino-functionalized adsorption material. The mass-volume ratio of graphene oxide to the Tris-hydrochloric acid buffer solution was 2 mg:1 mL, and the mass ratio of graphene oxide to 3,4-dihydroxyphenylacetamide was 1:1. In the glutaraldehyde solution, the mass-volume ratio of glutaraldehyde to deionized water was 1:3. In the coated graphene dispersion liquid, the mass-volume ratio of coated graphene to deionized water was 3 mg:2 mL. The mass of the glutaraldehyde solution was measured based on the mass of glutaraldehyde therein, and the mass of the coated graphene was measured based on the mass of 3,4-dihydroxyphenylacetamide therein. The mass ratio of 3,4-dihydroxyphenylacetamide to glutaraldehyde was 1:5, and the mass ratio of 3,4-dihydroxyphenylacetamide to N-isopropyl-1,3-diaminopropane was 2:5.

[0142] Example 7: The difference between this example and Example 5 is only in the preparation of the amino-functionalized adsorption material.

[0143] Preparation of the amino-functionalized adsorptive material: graphene oxide was dispersed in Tris-hydrochloric acid buffer solution with pH 8.5, and ultrasonic treatment was performed for 2 h, 3,4-dihydroxyphenylacetamide was added, and stirring was performed at 30 °C for 24 h, centrifugal separation was performed at 8000 rpm for 10 min, and then washing was performed with deionized water, and freeze-drying was performed at -50 °C for 48 h to obtain graphene coating; glutaraldehyde was dissolved in deionized water to obtain a glutaraldehyde solution; graphene coating was dispersed in deionized water to obtain a graphene coating dispersion, the glutaraldehyde solution was added, stirring was performed at room temperature for 30 min, N-isopropyl-1,3-diaminopropane and N-vinyl-N-methylacetamide were added, stirring was performed at room temperature for 18 h, centrifugal separation was performed at 8000 rpm for 10 min, washing was performed with deionized water, and freeze-drying was performed at -50 °C for 48 h to obtain the amino-functionalized adsorptive material. The mass-volume ratio of graphene oxide to Tris-hydrochloric acid buffer solution was 2 mg: 1 mL, and the mass ratio of graphene oxide to 3,4-dihydroxyphenylacetamide was 2:1; in the glutaraldehyde solution, the mass-volume ratio of glutaraldehyde to deionized water was 1:3; in the graphene coating dispersion, the mass-volume ratio of graphene coating to deionized water was 3 mg: 2 mL; the mass of the glutaraldehyde solution was measured based on the mass of glutaraldehyde therein, the mass of graphene coating was measured based on the mass of 3,4-dihydroxyphenylacetamide therein, the mass ratio of 3,4-dihydroxyphenylacetamide to glutaraldehyde was 1:5, the mass ratio of 3,4-dihydroxyphenylacetamide to N-isopropyl-1,3-diaminopropane was 2:5, and the mass ratio of 3,4-dihydroxyphenylacetamide to N-vinyl-N-methylacetamide was 2:1.

[0144] Example 8: This example is different from Example 5 only in the preparation of the amino-functionalized adsorptive material.

[0145] Preparation of the amino-functionalized adsorption material: graphene oxide was dispersed in Tris-hydrochloric acid buffer solution with pH 8.5, and ultrasonic for 2 h, then 3,4-dihydroxyphenylacetamide was added, and stirred at 30℃ for 24 h, centrifuged at 8000 rpm for 10 min, washed with deionized water, and then freeze-dried at-50℃ for 48 h to obtain coated graphene; glutaraldehyde was dissolved in deionized water to obtain a glutaraldehyde solution; the coated graphene was dispersed in deionized water to obtain a coated graphene dispersion, and the glutaraldehyde solution was added, and stirred at room temperature for 30 min, then N-isopropyl-1,3-diaminopropane and N-vinyl-N-methylacetamide were added, and stirred at room temperature for 18 h, centrifuged at 8000 rpm for 10 min, washed with deionized water, and then freeze-dried at-50℃ for 48 h to obtain the amino-functionalized adsorption material. The mass-volume ratio of graphene oxide to Tris-hydrochloric acid buffer solution was 2 mg:1 mL, and the mass ratio of graphene oxide to 3,4-dihydroxyphenylacetamide was 2:1; in the glutaraldehyde solution, the mass-volume ratio of glutaraldehyde to deionized water was 1:3; in the coated graphene dispersion, the mass-volume ratio of coated graphene to deionized water was 3 mg:2 mL; the mass of the glutaraldehyde solution was measured by the mass of glutaraldehyde therein, the mass of the coated graphene was measured by the mass of 3,4-dihydroxyphenylacetamide therein, the mass ratio of 3,4-dihydroxyphenylacetamide to glutaraldehyde was 1:5, the mass ratio of 3,4-dihydroxyphenylacetamide to N-isopropyl-1,3-diaminopropane was 2:5, and the mass ratio of 3,4-dihydroxyphenylacetamide to N-vinyl-N-methylacetamide was 1:1.

[0146] Comparative Example 1: This comparative example is compared with Example 1, and the only difference is the separation of product components.

[0147] The separation unit flow diagram of Comparative Example 1 is shown in Figure 6 , which includes a heavy component removal tower, a solvent separation tower, a 1-hexene separation tower, and a 1-octene separation tower.

[0148] Separation of product components: the product components enter the heavy component removal tower, and the overhead is separated to obtain an intermediate component, and the bottom is separated to obtain a heavy component; the intermediate component enters the solvent separation tower, and the overhead is separated to obtain an overhead stream, and the bottom is separated to obtain a bottom stream; the overhead stream enters the 1-hexene separation tower, and the overhead is separated to obtain 1-hexene, and the bottom is separated to obtain a C6 byproduct; the bottom stream enters the 1-octene separation tower, and the overhead is separated to obtain a circulating solvent, and the bottom is separated to obtain 1-octene. The operating temperature of the heavy component removal tower is 180℃, and the operating pressure is 0.1 MPaG; the operating temperature of the solvent separation tower is 190℃, and the operating pressure is 0.2 MPaG; the operating temperature of the 1-hexene separation tower is 120℃, and the operating pressure is 0.1 MPaG; the operating temperature of the 1-octene separation tower is 150℃, and the operating pressure is 0.2 MPaG.

[0149] Comparative Example 2: This comparative example is compared with Example 5, the only difference is the preparation of the amino-functionalized adsorbent material.

[0150] Preparation of the amino-functionalized adsorbent material: graphene oxide was dispersed in Tris-hydrochloric acid buffer solution with pH 8.5, ultrasonic for 2 h, 3,4-dihydroxyphenylacetamide was added, stirring at 30℃ for 24 h, centrifugation at 8000 rpm for 10 min, washed with deionized water, and then freeze-dried at minus 50℃ for 48 h to obtain the coated graphene, i.e. the amino-functionalized adsorbent material. The mass-volume ratio of graphene oxide to Tris-hydrochloric acid buffer solution was 2 mg:1 mL, and the mass ratio of graphene oxide to 3,4-dihydroxyphenylacetamide was 2:1.

[0151] Comparative Example 3: This comparative example is compared with Example 5, the only difference is the preparation of the amino-functionalized adsorbent material.

[0152] Preparation of the amino-functionalized adsorbent material: glutaraldehyde was dissolved in deionized water to obtain a glutaraldehyde solution; graphene oxide was dispersed in Tris-hydrochloric acid buffer solution with pH 8.5 to obtain a graphene dispersion solution, the glutaraldehyde solution was added, stirring at room temperature for 30 min, N-isopropyl-1,3-diaminopropane was added, stirring at room temperature for 18 h, centrifugation at 8000 rpm for 10 min, washed with deionized water, and then freeze-dried at minus 50℃ for 48 h to obtain the amino-functionalized adsorbent material. In the glutaraldehyde solution, the mass-volume ratio of glutaraldehyde to deionized water was 1:3; in the graphene dispersion solution, the mass-volume ratio of graphene oxide to Tris-hydrochloric acid buffer solution was 2 mg:1 mL; the mass of the glutaraldehyde solution was measured by the mass of glutaraldehyde therein, the mass ratio of graphene oxide to glutaraldehyde was 2:5, and the mass ratio of graphene oxide to N-isopropyl-1,3-diaminopropane was 4:5.

[0153] Comparative Example 4: This comparative example is compared with Example 5, the only difference is the preparation of the purified circulating solvent.

[0154] Preparation of the purified circulating solvent: the separated circulating solvent was dispersed in deionized water to obtain a circulating solvent dispersion solution, graphene oxide was added, stirring at 40℃ and 200 rpm for 8 h, centrifugation at 8000 rpm for 10 min, the upper liquid was collected, washed with deionized water, dried with anhydrous magnesium sulfate, filtered to obtain the purified circulating solvent. In the circulating solvent dispersion solution, the volume ratio of the circulating solvent to deionized water was 3:5; the volume-mass ratio of the circulating solvent to graphene oxide was 1 mL:0.3 mg, and the volume-mass ratio of the circulating solvent to anhydrous magnesium sulfate was 1 mL:2 mg.

[0155] Test Example 1: Separation purity test of product components.

[0156] Test sample: Example 1-2 for separation of product components.

[0157] Test method: The purity of the products separated from the top and bottom of the different separation columns was tested by gas chromatography, using a flame ionization detector and an HP-5 capillary column, with a temperature program including 40°C for 3 min, increasing to 200°C at 10°C / min for 3 min, nitrogen as the carrier gas at a flow rate of 1 mL / min, a sample size of 5 μL, and a split ratio of 50:1.

[0158] In Example 1, the solvent pre-separation column exhibited precise light and heavy component cutting ability, the overhead could efficiently enrich C6 components and lighter components C6- of more than 99 wt% in the feed, while precisely controlling 10-90% of the solvent to be produced with the light components, avoiding the residual light components in the heavy phase in the column bottom; the column bottom could trap C8 and heavier components of more than 99 wt% without C6 components and lighter components C6-, avoiding the interference of light components on the subsequent separation of C8 components from the source; the subsequent 1-hexene separation column could further achieve deep separation of light components, with the purity of C6 and C6 components below the column top being more than 99%, ensuring the high-purity recovery of methylcyclopentane, methylenecyclopentane and 1-hexene; the purity of the solvent in the column bottom reached more than 99% at the same time, directly meeting the recycling requirement; the overhead of the solvent separation column could recover the recycled solvent with a purity of more than 99%, and the column bottom could enrich C8 and heavier components of more than 99%; the purity of 1-octene in the overhead of the 1-octene light separation column was more than 99%, and the purity of C10 and heavier components in the column bottom also reached more than 99%, achieving complete separation of the target product and heavy components, effectively solving the problems of component cross-contamination and solvent entrainment in traditional sequential separation.

[0159] In Example 2, the 1-octene pre-separation column exhibited excellent separation effect of intermediate components and heavy components, the overhead could produce more than 99 wt% of the solvent and lighter components C6-, while controlling 10-90% of the C8 components to be produced with the intermediate components, avoiding the residual solvent in the heavy phase in the column bottom; the column bottom trapped C10 and heavier components of more than 99 wt% without the solvent and lighter components C6-, eliminating the pollution of heavy components to C8 components; the heavy component removal column could precisely separate C8 components and heavy components, with the purity of 1-octene in the overhead reaching more than 99% and the purity of C10 and heavier components in the column bottom being more than 99%, ensuring the complete removal of heavy components. The 1-octene heavy separation column and the 1-hexene separation column further achieved fine separation of components, the overhead of the 1-octene heavy separation column could recover a mixture of C4, C6 and solvent with a purity of more than 99%, and the purity of 1-octene in the column bottom was maintained at more than 99%; the purity of C4 and C6 components in the overhead of the 1-hexene separation column reached more than 99%, and the purity of the solvent in the column bottom was more than 99%, also achieving high-purity recovery of each target component and recycling of the solvent.

[0160] Test Example 2: Energy consumption test of separation units.

[0161] Test samples: separation units of Examples 1-4 and Comparative Example 1.

[0162] Test method: each separation unit was built according to the process of the corresponding example or comparative example and was debugged to a stable running state, the feed components, feed flow rate of each separation unit were controlled to be consistent with the actual industrial production conditions, and the operating temperature and operating pressure of each separation tower strictly followed the parameters set in the corresponding example or comparative example; high-precision calorimeters were used to monitor the cold load QC and heat load QR of each separation tower in real time, the cold load and heat load data within 24 hours of stable operation of each tower were continuously recorded, the average value of the cold load and the average value of the heat load of each separation tower within the time period were calculated, and the average values of the cold load of all separation towers in the same separation unit were added to obtain the total cold load of the unit, and the average values of the heat load were added to obtain the total heat load of the unit, wherein the cold load was represented by a negative value indicating the heat to be removed by the system, and the heat load was represented by a positive value indicating the heat to be input by the system.

[0163] The energy consumption test results of the separation unit in Example 1 are shown in Table 1, the energy consumption test results of the separation unit in Example 2 are shown in Table 2, the energy consumption test results of the separation unit in Example 3 are shown in Table 3, the energy consumption test results of the separation unit in Example 4 are shown in Table 4, and the energy consumption test results of the separation unit in Comparative Example 1 are shown in Table 5.

[0164] Table 1 Energy consumption test results of the separation unit in Example 1

[0165] Table 2 Energy consumption test results of the separation unit in Example 2

[0166] Table 3 Energy consumption test results of the separation unit in Example 3

[0167] Table 4 Energy consumption test results of the separation unit in Example 4

[0168] Table 5 Energy consumption test results of the separation unit in Comparative Example 1

[0169] The total cold load of the separation unit of Comparative Example 1 using the traditional sequential separation is -7065 kW, and the total heat load is 6353 kW, which is significantly higher than the separation units of Embodiments 1-4 of the present application; the total cold load of the separation unit of Embodiment 1 is -6318 kW, and the total heat load is 5974 kW, and the total cold load of the separation unit of Embodiment 2 is -6327 kW, and the total heat load is 6141 kW, both of which break through the limitation of the traditional fixed sequential separation by differentiating the rectification path, and reduce the energy loss caused by the repeated temperature rise and fall of the tower body and the high reflux ratio, so the energy consumption is significantly lower than that of Comparative Example 1; the total cold load of the separation unit of Embodiment 3 using a single partition wall tower is only -1556 kW, and the total heat load is 2362 kW, and the total cold load of the separation unit of Embodiment 4 using a double partition wall tower is -5652 kW, and the total heat load is 5400 kW, wherein the energy consumption of Embodiment 3 is the lowest, because the partition wall tower integrates the separation function of multiple towers, greatly reducing the number of tower bodies and the loss in the energy transfer process, further verifying the significant advantage of the separation unit of the present application in reducing energy consumption, especially the application of the partition wall tower structure can maximize the optimization of energy utilization efficiency.

[0170] Test Example 3: Test of adsorption capacity of adsorbent material.

[0171] Test sample: amino-functionalized adsorbent material or graphene oxide prepared in Embodiments 5-8 and Comparative Examples 2-4.

[0172] Test method: prepare a circulating solvent test solution containing Zr 4+ with an initial concentration of 10 μg / L, add 10 μg of amino-functionalized adsorbent material or graphene oxide to 20 mL of the circulating solvent test solution, oscillate and adsorb for 8 h under the condition of 40°C and 200 rpm, centrifuge the mixed solution under the condition of 8000 rpm for 10 min, filter the supernatant through a 0.22 μm organic filter membrane, and determine the equilibrium concentration of Zr 4+ in the supernatant by inductively coupled plasma mass spectrometry. The adsorption capacity is calculated according to the formula Q (mg / g) = (C0-C e ) x V / m, wherein Q is the adsorption capacity, C0is the initial concentration of Zr 4+ , V is the volume of the test solution, and m is the mass of the adsorbent material.

[0173] The test results of the adsorption capacity of the adsorbent material prepared in the present application are shown in Table 6.

[0174] Table 6 Test results of adsorption capacity of adsorbent material

[0175] The amino-functionalized adsorption materials prepared in Examples 5-8 have a significantly higher adsorption capacity than the graphene oxide in Comparative Example 3 after a complete amino-functionalized modification process; Example 5 realizes sufficient coating of graphene oxide by 3,4-dihydroxyphenylacetamide to optimize the material matrix structure, and a large number of amino active sites that can specifically adsorb target impurities are formed by cross-linking and grafting N-isopropyl-1,3-diaminopropane with glutaraldehyde, and the material has good dispersibility, which is beneficial to the contact between impurities and adsorption sites; Example 6 increases the amount of 3,4-dihydroxyphenylacetamide to more fully coat graphene oxide to build a more optimal matrix structure, providing more attachment sites for subsequent amino grafting, and the adsorption capacity is improved compared with Example 3; Example 7 introduces N-vinyl-N-methylacetamide to further increase the number of amino functional sites and improve the dispersion stability of the material in the circulating solvent system, and the adsorption capacity is further improved; Example 8 increases the amount of N-vinyl-N-methylacetamide, so that the adsorption sites are more abundant, and the adsorption capacity reaches the highest; Comparative Example 2 does not perform glutaraldehyde cross-linking and amino grafting, and Comparative Example 3 does not coat graphene oxide with 3,4-dihydroxyphenylacetamide, but directly modifies the original graphene oxide with amino, resulting in poor material structure integrity and lower adsorption capacity than Example 1.

[0176] Test Example 4: Purity test of purified circulating solvent.

[0177] Test sample: purified circulating solvent prepared in Examples 5-8 and Comparative Examples 2-4.

[0178] Test method: 1 mL of purified circulating solvent was diluted to 10 mL with anhydrous ethanol to obtain a sample test solution, which was filtered through a 0.22 μm organic filter membrane after standing for 5 min to remove small impurities. A gas chromatograph was used for purity determination, and an HP-5 capillary column, 30 m x 0.32 mm x 0.25 μm, was used as the chromatographic column, and a flame ionization detector was used as the detector; the injection port temperature was set to 250℃, the detector temperature was set to 300℃, the carrier gas was high-purity nitrogen, and the carrier gas flow rate was 1 mL / min; the temperature program was as follows: the initial temperature was 40℃, maintained for 3 min, then increased to 200℃ at a rate of 10℃ / min and maintained for 5 min; the injection volume was 1 μL, and the split ratio was 50:1; each sample was injected continuously for 3 times, and the mass fraction of the circulating solvent was calculated by peak area normalization method.

[0179] The purity test results of the purified circulating solvent prepared in the present application are shown in Table 7.

[0180] Table 7 Purity test results of purified 1-octene

[0181] Example 5: By 3,4-dihydroxyphenylacetamide, the graphene oxide is fully coated to optimize the material matrix structure, with glutaraldehyde cross-linking grafting N-isopropyl-1,3-diaminopropane, forming a large number of amino active sites that can specifically adsorb the residual impurities after rectification, and the material has good dispersibility in the circulating solvent system, which is beneficial to the full contact of impurities and adsorption sites, and the impurity removal effect is excellent, and the purity is at a high level; Example 6: The amount of 3,4-dihydroxyphenylacetamide is increased, which more fully coats the graphene oxide to build a more optimal matrix structure, providing more attachment sites for subsequent amino grafting, increasing the number of amino active sites, enhancing the impurity removal capacity, and improving the purity compared with Example 3; Example 7: N-vinyl-N-methylacetamide is introduced when preparing the adsorption material, which can further increase the number of amino functional sites and improve the dispersion stability of the material in the circulating solvent system, further improving the contact efficiency of impurities and adsorption sites, and further improving the purity compared with Example 4; Example 8: The amount of N-vinyl-N-methylacetamide is increased, making the amino functional sites on the surface of the adsorption material more abundant, and the material has better dispersibility, and the adsorption and removal effect of impurities reaches the best, so the purity is the highest among all samples; Comparative Example 2: The adsorption material is prepared without glutaraldehyde cross-linking and amino grafting, and only the graphene oxide is coated with 3,4-dihydroxyphenylacetamide, and the material surface lacks amino active sites for specifically adsorbing impurities, and the impurity removal effect is limited, and the purity is lower than that of Example 3; Comparative Example 3: 3,4-dihydroxyphenylacetamide is not used to coat the graphene oxide, and the original graphene oxide is directly modified with amino, resulting in poor material structure integrity, uneven distribution of amino active sites, and limited number of amino active sites, and the impurity removal effect is worse than that of Comparative Example 1, and the purity is further reduced; Comparative Example 4: The original graphene oxide without any functional modification is directly used, and although only physical adsorption is used to remove impurities, it lacks specific active sites, and the purity is the lowest.

[0182] The above-described examples and / or embodiments are merely used to illustrate the preferred examples and / or embodiments of the present technology, and do not limit the embodiments of the present technology in any form, and any person skilled in the art can make some changes or modifications to other equivalent examples without departing from the scope of the technology disclosed in the present disclosure, and such changes or modifications should be considered as substantially the same technology or embodiments as the present disclosure.

[0183] The principles and implementation manners of the present application are described herein by using specific examples, and the above example descriptions are only used to help understand the method of the present application and its core idea. The above descriptions are only preferred embodiments of the present application, and it should be pointed out that, due to the limited nature of the language expression, there are objectively infinite specific structures, and for ordinary skilled persons in the technical field, some improvements, refinements or changes can be made without departing from the principles of the present application, and the above technical features can also be combined in an appropriate manner; these improvements, refinements, changes or combinations, or the direct application of the inventive concept and technical solution to other occasions without improvement, shall be regarded as the protection scope of the present application.

Claims

1. A method for separating products from solution polymerization reactions, characterized in that: The separation method includes separation via distillation path or separation via partitioned column integration. The separation via distillation path includes solvent pre-separation or 1-octene pre-separation. The separation via partitioned column integration includes separation via single partitioned column or separation via double partitioned column. The solvent pre-separation scheme includes a solvent pre-separation tower, a C6 separation tower, a 1-hexene separation tower, a solvent separation tower, and a 1-octene light separation tower; the 1-octene pre-separation scheme includes a 1-octene pre-separation tower, a 1-octene heavy separation tower, a C6 separation tower, a 1-hexene separation tower, and a heavy separation tower. The separation products of the separation method include C6 byproducts, 1-hexene, 1-octene, recycled solvent, and heavy components, wherein the C6 byproducts include methylcyclopentane and methylenecyclopentane.

2. The method for separating solution polymerization products according to claim 1, characterized in that: The solvent pre-separation tower operates at a temperature of 100-200℃ and a pressure of 0-0.2 MPaG; the C6 separation tower operates at a temperature of 70-170℃ and a pressure of 0-0.2 MPaG; the 1-hexene separation tower operates at a temperature of 60-130℃ and a pressure of 0-0.2 MPaG; the solvent separation tower operates at a temperature of 110-200℃ and a pressure of 0.1-0.3 MPaG; the 1-octene light separation tower operates at a temperature of 80-210℃ and a pressure of -0.1-0.1 MPaG; the stream collected from the top of the solvent pre-separation tower contains more than 99 wt% of the C6 component and the lighter component C6- from the feed, and 10-90 wt% of the total solvent component from the feed is collected; the stream collected from the bottom of the tower contains the remaining solvent component after the top collection, as well as more than 99 wt% of the 1-octene and heavy components from the feed.

3. The method for separating solution polymerization products according to claim 1, characterized in that: The operating temperature of the 1-octene pre-separation tower is 120-220℃, and the operating pressure is 0.1-0.3 MPaG; the operating temperature of the 1-octene heavy separation tower is 100-190℃, and the operating pressure is 0.1-0.3 MPaG; the operating temperature of the C6 separation tower is 70-170℃, and the operating pressure is 0-0.2 MPaG; the operating temperature of the 1-hexene separation tower is 60-130℃, and the operating pressure is 0-0.2 MPaG; the operating temperature of the heavy separation tower is 80-210℃, and the operating pressure is -0.1-0.1 MPaG; the stream collected from the top of the 1-octene pre-separation tower contains more than 99 wt% of the solvent, C6 component and lighter component C6- from the feed, and 10-90 wt% of the total 1-octene component from the feed is collected; the stream collected from the bottom of the tower contains the remaining 1-octene component after the top collection, and more than 99 wt% of the heavy components from the feed.

4. The method for separating solution polymerization products according to claim 1, characterized in that: In the solvent pre-separation, the top stream of the solvent pre-separation tower is separated to obtain the top stream, and the bottom stream is separated to obtain the bottom stream. The overhead stream from the column enters a 1-hexene separation column, where C6 fraction is separated at the top and recycled solvent is separated at the bottom. The C6 component enters a C6 separation column, where 1-hexene is separated at the top and C6 by-products, including methylcyclopentane and methylenecyclopentane, are separated at the bottom. The bottom stream enters a solvent separation column, where recycled solvent is separated at the top and intermediate components are separated at the bottom. The intermediate components enter a 1-octene light separation column, where 1-octene is separated at the top and heavy components are separated at the bottom.

5. The method for separating solution polymerization products according to claim 1, characterized in that: In the 1-octene pre-separation, the top of the 1-octene pre-separation column yields a pre-separation column overhead stream, and the bottom of the column yields a bottom stream; the pre-separation column overhead stream enters a 1-octene heavy separation column, where the top of the column yields a heavy separation column overhead stream, and the bottom of the column yields 1-octene; the heavy separation column overhead stream enters a 1-hexene separation column, where the top of the column yields the C6 component, and the bottom of the column yields recycled solvent; The C6 component enters a C6 separation tower, where 1-hexene is separated at the top and C6 by-products, including methylcyclopentane and methylenecyclopentane, are separated at the bottom. The bottom stream enters a deweighting tower, where 1-octene is separated at the top and heavy components are separated at the bottom.

6. The method for separating solution polymerization products according to claim 1, characterized in that: The single-walled column separates 1-hexene at the top, C6 byproducts from the side stream, and solvent from the bottom; the single-walled column has a distillation temperature of 50-250℃ and an operating pressure of 0-0.3 MPaG; the C6 byproducts include methylcyclopentane and methylenecyclopentane.

7. The method for separating solution polymerization products according to claim 1, characterized in that: The dual-walled column includes a first walled column and a second walled column. The sidestream product of the first walled column yields 1-octene, the bottom product yields a heavy component, and the top product yields 1-hexene, a C6 byproduct, and a solvent. This product flows to the second walled column. The top product of the second walled column yields 1-hexene, the sidestream product yields a C6 byproduct, and the bottom product yields a solvent. The distillation temperature of the first walled column is 50-300℃, and the operating pressure is -0.1-0.3 MPaG. The distillation temperature of the second walled column is 50-250℃, and the operating pressure is 0.01-0.3 MPaG. The C6 byproduct includes methylcyclopentane and methylenecyclopentane.

8. The method for separating solution polymerization products according to claim 1, characterized in that: The catalyst for solution polymerization includes ligand a, transition metal compound b, and activator c. Ligand a includes PNP ligands, PNNP ligands, and rigid linking groups. Transition metal compound b is a metal compound of group IVB-VIII. Activator c is a compound containing a group IIIA metal.

9. The method for separating solution polymerization products according to claim 1, characterized in that: The circulating solvent is purified by an amino-functionalized adsorbent material to obtain a purified circulating solvent. The core layer of the amino-functionalized adsorbent material includes graphene oxide, and the shell layer of the amino-functionalized adsorbent material is formed by grafting a modifier with a crosslinking agent. The modifier includes 3,4-dihydroxyphenylacetamide and N-isopropyl-1,3-diaminopropane.

10. The method for separating solution polymerization products according to claim 8, characterized in that: The mass ratio of graphene oxide to 3,4-dihydroxyphenylacetamide is 2:0.5-3, and the mass ratio of 3,4-dihydroxyphenylacetamide to N-isopropyl-1,3-diaminopropane is 2:0.5-5.

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