Refining system of dicyclopentadiene dioxide

Abstract

The utility model discloses a dicyclopentadiene dioxide refining system. The dicyclopentadiene dioxide refining system comprises one or more dissolution-crystallization-separation units and a drying unit which are connected in sequence, wherein each dissolution-crystallization-separation unit independently comprises a dissolution kettle, an adsorption subunit, an optional filtering subunit, a crystallization kettle, a centrifugal machine and an optional feeding machine in sequence, the feeding machine is a screw conveyor, each adsorption subunit independently comprises two or more adsorption towers which are connected in parallel, and the two or more adsorption towers are connected in parallel. The drying unit comprises a drying machine, and the filtering subunit comprises two or more filters which are connected in parallel. According to the dicyclopentadiene dioxide purification device, a method of combining recrystallization with physical adsorption is creatively applied, materials do not need to be manually contacted, automatic operation can be realized in pilot plant test and industrial devices, and safe and effective purification of dicyclopentadiene dioxide is realized.

Description

Technical Field

[0001] The utility model belongs to the separation of dicyclopentadiene dioxide materials, and particularly relates to a refining system for dicyclopentadiene dioxide. Background Art

[0002] Dicyclopentadiene (DCPD) is an important component in the C5 fraction of petroleum cracking, accounting for about 14-19% of the C5 fraction. The epoxidation product of dicyclopentadiene, dicyclopentadiene dioxide (DCPDDO), is an alicyclic epoxide with excellent properties. Compared with ordinary epoxy resins, dicyclopentadiene dioxide has better performance in terms of high temperature resistance, heat resistance, weather resistance, ultraviolet resistance, electrical insulation, and high strength. Based on the above properties, dicyclopentadiene dioxide is widely used in high-temperature casting materials, fiberglass, adhesives, laminates, and electronic device encapsulation, etc.

[0003] Alicyclic epoxides are generally formed by the epoxidation reaction of olefins. The commonly used synthesis methods mainly include: organic peroxyacid method, inorganic peroxide method, alkyl hydroperoxide method, hypochlorous acid addition method, hydrogen peroxide-heteropolyacid compound method. In the prior art, dicyclopentadiene dioxide is usually prepared by the epoxidation reaction of dicyclopentadiene using methods such as peracetic acid method, chlorohydrin method, and hydroperoxide catalytic epoxidation method. However, currently, all these three methods have deficiencies, such as complex reaction processes, serious equipment corrosion, easy acidic ring-opening of epoxides to generate by-products, and large emissions of "three wastes". In recent years, a green epoxidation process using hydrogen peroxide as the oxygen source and heteropolyacid compounds as the catalyst has received wide attention.

[0004] CN114426549A discloses a preparation method of high-purity dicyclopentadiene dioxide DCPDDO, including: using titanium silicalite molecular sieve as the catalyst, in the presence of an inert solvent, DCPD reacts with CHP to generate DCPDDO and 2-phenyl-2-propanol; through rectification separation, the solvent and 2-phenyl-2-propanol are collected at the top of the column, and DCPDDO is obtained at the bottom of the column. After two crystallization separations and vacuum drying, high-purity solid DCPDDO is obtained. The unreacted raw materials or mono-oxidized dicyclopentadiene in the crystallization mother liquor are mixed with fresh reaction raw materials and sent to the reactor for continuous reaction. The preparation process of this invention can reuse the unreacted raw materials, has simple control of material ratio, high product yield, significantly reduced waste liquid emissions, and safe and simple process operation, providing a green reaction process for synthesizing DCPDDO.

[0005] The prior art is only applicable to small-scale laboratory preparations, relying on manual operations such as manual transfer of materials, etc., and there is a safety risk of organic solvents being exposed to the air, and it cannot be used for pilot-scale and industrial large-scale automated production. Summary of the Utility Model

[0006] In order to overcome the problems existing in the prior art, the utility model provides a refining system for dicyclopentadiene dioxide, which innovatively uses the method of recrystallization combined with physical adsorption, without manual contact with materials, and can realize automatic operation in pilot and industrial plants, achieving safe and effective purification of dicyclopentadiene dioxide.

[0007] One of the purposes of the utility model is to provide a refining system for dicyclopentadiene dioxide, including: one or more dissolution-crystallization-separation units connected in sequence, and a drying unit; wherein, each dissolution-crystallization-separation unit independently includes a dissolution kettle, an adsorption sub-unit, an optional filtration sub-unit, a crystallization kettle, a centrifuge and an optional feeder in sequence, the feeder is a screw conveyor, each adsorption sub-unit independently includes two or more parallel adsorption towers, the drying unit includes a dryer, and the filtration sub-unit includes two or more parallel filters.

[0008] Wherein, activated carbon and / or clay are filled in the adsorption tower. The one or more dissolution-crystallization-separation units and the drying unit are connected in sequence through pipelines.

[0009] In a preferred embodiment, there are more than two dissolution-crystallization-separation units, preferably 2-5, more preferably 2-4, such as 2, 3 or 4.

[0010] Through in-depth research by the inventor, it is first found that in the products obtained by the prior art, the chromogenic substance is a viscous lipophilic organic substance, and in the secondary crystallization process of the prior art, mechanical filtration can only filter out solid impurities and cannot filter out viscous lipophilic chromogenic substances. The utility model innovatively uses the method of recrystallization combined with physical adsorption for the crude DCPDDO product, obtains a high-purity product, adsorbs and removes the viscous lipophilic chromogenic impurities after dissolution, and finally obtains a white and fluffy product, significantly improving the product appearance and product quality.

[0011] In a preferred embodiment, a condenser is independently provided at the top of each dissolution kettle to condense the tail gas and recover the condensate in the tail gas; and / or, a protective gas feed pipeline I and a crude material feed pipeline are independently provided on each dissolution kettle.

[0012] In a preferred embodiment, within each dissolution-crystallization-separation unit: the discharge end of the dissolution kettle is connected to the feed end of the adsorption sub-unit through a pipeline, and / or, the discharge end of the adsorption sub-unit is connected to the feed end of the crystallization kettle through a pipeline, and / or, the discharge end of the crystallization kettle is connected to the feed end of the centrifuge through a pipeline.

[0013] In a further preferred embodiment, a liquid discharge port and a solid discharge port are provided on the centrifuge. Among them, a liquid discharge pipeline is provided on the liquid discharge port, and the solid discharge port is connected to the feed end of the feeder or the feed end of the dissolution kettle of the next dissolution-crystallization-separation unit or the feed end of the drying unit through a pipeline.

[0014] Preferably, when the dissolution-crystallization-separation unit does not include a feeder, the solid discharge port of the centrifuge is connected to the dissolution kettle or the drying unit of the next dissolution-crystallization-separation unit through a pipeline, and the centrifuge is located directly above the dissolution kettle or the drying unit of the next dissolution-crystallization-separation unit.

[0015] In a further preferred embodiment, the discharge end of the feeder is connected to the dissolution kettle in the next dissolution-crystallization-separation unit through a pipeline, or is connected to the drying unit through a pipeline.

[0016] In a preferred embodiment, the feeder is a screw conveyor.

[0017] In a preferred embodiment, the drying unit includes a dryer and a cooler. A protective gas feed pipeline II, a product discharge pipeline and a gas phase discharge pipeline are provided on the dryer.

[0018] In a further preferred embodiment, the cooler is provided on the gas phase discharge pipeline.

[0019] In a preferred embodiment, the system further optionally includes a vacuum unit.

[0020] In a further preferred embodiment, the vacuum unit is connected to the drying unit, preferably connected to the cooler of the drying unit.

[0021] Among them, when a vacuum system is included, the dryer uses vacuum drying; when a vacuum system is not included, the dryer uses a protective gas such as nitrogen for purge drying.

[0022] In a preferred embodiment, along the material flow direction, the liquid discharge port of the centrifuge in the last dissolution-crystallization-separation unit is connected to the feed end of the dissolution kettle in the first dissolution-crystallization-separation unit through a liquid phase circulation loop.

[0023] In a preferred embodiment, when there are N dissolution-crystallization-separation units, N≥2, fresh solvent (such as cyclohexane) feed pipelines are independently provided on the dissolution kettles in the 2nd to Nth dissolution-crystallization-separation units (along the material flow direction).

[0024] In a preferred embodiment, each dissolution-crystallization-separation unit optionally includes a filtration subunit independently, and the filtration subunit includes two or more filters connected in parallel.

[0025] In a further preferred embodiment, the filtration subunit is disposed between the adsorption subunit and the crystallization kettle.

[0026] In an even more preferred embodiment, the filter is a basket filter or a bag filter.

[0027] The method for purification using the purification system includes the following steps:

[0028] a) The raw material is heated and dissolved in a dissolution kettle to form a solution;

[0029] b) The solution in step a) is adsorbed by the adsorption subunit to remove the chromogenic impurities and obtain a colorless solution;

[0030] c) The solution in step b) is cooled and crystallized in a crystallization kettle to form a solid-liquid mixture;

[0031] d) The solid-liquid mixture in step c) passes through a centrifuge to separate the solid from the liquid. The liquid is sent for off-site treatment and / or returned to the dissolution kettle, and the solid is sent to a drying unit;

[0032] e) The solid in step d) is dried in a drying unit to obtain the product.

[0033] The raw material is a crude dicyclopentadiene dioxide material, which contains dicyclopentadiene dioxide, α,α-dimethylbenzyl alcohol and other substances, and optionally contains monocyclopentadiene monoxide and / or cumene hydroperoxide;

[0034] Preferably, based on 100 wt% of the dicyclopentadiene dioxide-containing material, the dicyclopentadiene dioxide is 30-90 wt%, the α,α-dimethylbenzyl alcohol is 1-30 wt%, the monocyclopentadiene monoxide is 0-4 wt%, the cumene hydroperoxide is 0-4 wt%, and the other substances are 0-2 wt%.

[0035] Preferably, the other substances include cumene, phenol, acetophenone and chromogenic substances.

[0036] The solvent used for dissolution is cyclohexane. The dissolution kettle is heated by electric heating or heat medium heat exchange, and the crystallization kettle is cooled by refrigerant heat exchange.

[0037] The endpoints and any values in the ranges disclosed in the present utility model are not limited to the exact ranges or values. These ranges or values should be understood to include values close to these ranges or values. For numerical ranges, between the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values, they can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein. In the following text, in principle, various technical solutions can be combined with each other to obtain new technical solutions, which should also be regarded as specifically disclosed herein.

[0038] Compared with the prior art, the present utility model has the following beneficial effects:

[0039] (1) The adsorption tower is used to adsorb and remove the chromogenic impurities that cannot be removed by recrystallization and filtration, significantly improving the product quality and increasing the product purity;

[0040] (2) By adopting the method of combining recrystallization with physical adsorption, high-purity products are obtained;

[0041] (3) It has a high degree of automation and does not require manual contact with the materials, being suitable for large-scale production in pilot and industrial plants;

[0042] (4) The entire process is carried out in closed equipment and pipelines, and the materials only contact nitrogen and do not contact air, avoiding safety risks. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 A schematic diagram showing an embodiment of the system of the present utility model.

[0044] In Figure 1Among them, A - the first dissolving kettle, B - the first condenser, C - the first crystallization kettle, D - the first centrifuge, E - the second dissolving kettle, F - the second condenser, G - the second crystallization kettle, H - the second centrifuge, I - the dryer, J - the cooler, K - the vacuum system, L - the first feeder, M - the second feeder, NA - the first adsorption tower A, NB - the first adsorption tower B, OA - the second adsorption tower A, OB - the second adsorption tower B. 1 - Feed through the coarse material feed pipeline (the coarse material is the coarse dicyclopentadiene dioxide material), 2 - Feed through the first protective gas feed pipeline I, 3 - Discharge from the first dissolving kettle (dissolved solution), 4 - Tail gas from the first dissolving kettle, 5 - Tail gas from the first condenser, 6 - Discharge from the first adsorption sub-unit, 7 - Discharge from the first crystallization kettle, 8 - Discharge from the solid phase discharge port of the first centrifuge, 9 - Discharge through the liquid phase discharge pipeline, 10 - Feed through the fresh solvent feed pipeline (such as cyclohexane), 11 - Tail gas from the second dissolving kettle, 12 - Tail gas from the second condenser, 13 - Feed through the second protective gas feed pipeline I, 14 - Discharge from the second dissolving kettle (dissolved solution), 15 - Discharge from the second adsorption sub-unit, 16 - Discharge from the second crystallization kettle, 17 - Discharge from the solid phase discharge port of the second centrifuge, 18 - Recirculated material in the liquid phase circulation loop, 19 - Feed through the protective gas feed pipeline II, 20 - Discharge through the product discharge pipeline, 21 - Discharge through the gas phase discharge pipeline, 22 - Discharge from the cooler, 23 - Discharge from the vacuum system, 24 - Discharge from the first feeder, 25 - Discharge from the second feeder.

[0045] When adopting Figure 1 the system shown:

[0046] Feed the material fed through the coarse material feed pipeline (the coarse material is the coarse dicyclopentadiene dioxide material) 1 into the first dissolving kettle A, feed the material fed through the first protective gas feed pipeline I 2 (nitrogen) into the first dissolving kettle A. The tail gas 4 from the first dissolving kettle enters the first condenser B to obtain condensate and return it to the first dissolving kettle A, and the tail gas 5 from the first condenser goes for post-treatment. Feed the recirculated material 18 in the liquid phase circulation loop into the first dissolving kettle A, heat it up for dissolution, and the discharge from the first dissolving kettle (dissolved solution) 3 enters the first adsorption tower A (NA). NA and NB are in a one-open-one-spare mode. The discharge 6 from the first adsorption sub-unit obtained enters the first crystallization kettle C, cools down and crystallizes in the first crystallization kettle C to obtain the discharge 7 from the first crystallization kettle. The discharge 7 from the first crystallization kettle enters the first centrifuge D. The first centrifuge D separates to obtain the discharge 8 from the solid phase discharge port of the first centrifuge. The discharge 8 from the solid phase discharge port of the first centrifuge is transported through the first feeder L and serves as the discharge 24 from the first feeder to the second dissolving kettle E. The discharge 9 through the liquid phase discharge pipeline goes for treatment. Feed the material fed through the second protective gas feed pipeline I 13 (nitrogen) into the second dissolving kettle E. The tail gas 11 from the second dissolving kettle enters the second condenser F to obtain condensate and return it to the second dissolving kettle E, and the tail gas 12 from the second condenser goes for post-treatment.

[0047] Fresh solvent feed line feed (e.g., cyclohexane) 10 is introduced into the second dissolving kettle E, and after heating and dissolving, the discharge from the second dissolving kettle (dissolved solution) 14 is obtained. The discharge from the second dissolving kettle (dissolved solution) 14 enters the second adsorption tower O (OA). OA and OB are in an on-off standby mode. The discharge from the second adsorption sub-unit 15 enters the second crystallization kettle G, where it cools and crystallizes. The discharge from the second crystallization kettle 16 enters the second centrifuge H. The solid-phase discharge port of the second centrifuge discharges 17, which is transported by the second feeder M and serves as the discharge 25 of the second feeder to the dryer I. The circulating material 18 in the liquid-phase circulation loop is recycled to the first dissolving kettle A.

[0048] The dryer I is connected with a protective gas feed line II and a cooler J. The product discharge line of the dryer I discharges 20 to the product receiving equipment, and the gas-phase discharge line discharges 21 to the cooler J. After cooling, the discharge from the cooler 22 is obtained. The discharge from the cooler 22 is pumped to the vacuum system K, and the discharge from the vacuum system 23 is obtained.

[0049] Among them, the filter connected after the adsorption tower is omitted and not drawn, and the necessary pumps are omitted and not drawn, which does not mean their non-existence.

[0050] Figure 2 Schematic diagram showing an implementation manner of the system of the present utility model;

[0051] In Figure 2 A - first dissolving kettle, B - first condenser, C - first crystallization kettle, D - first centrifuge, E - second dissolving kettle, F - second condenser, G - second crystallization kettle, H - second centrifuge, I - dryer, J - cooler, K - vacuum system, NA - first adsorption tower A, NB - first adsorption tower B, OA - second adsorption tower A, OB - second adsorption tower B. 1 - feed of the coarse material feed line (the coarse material is the coarse dicyclopentadiene dioxide material), 2 - feed of the first protective gas feed line I, 3 - discharge from the first dissolving kettle (dissolved solution), 4 - tail gas from the first dissolving kettle, 5 - tail gas from the first condenser, 6 - discharge from the first adsorption sub-unit, 7 - discharge from the first crystallization kettle, 8 - discharge from the solid-phase discharge port of the first centrifuge, 9 - discharge from the liquid-phase external discharge line, 10 - feed of the fresh solvent feed line (e.g., cyclohexane), 11 - tail gas from the second dissolving kettle, 12 - tail gas from the second condenser, 13 - feed of the second protective gas feed line I, 14 - discharge from the second dissolving kettle (dissolved solution), 15 - discharge from the second adsorption sub-unit, 16 - discharge from the second crystallization kettle, 17 - discharge from the solid-phase discharge port of the second centrifuge, 18 - circulating material in the liquid-phase circulation loop, 19 - feed of the protective gas feed line II, 20 - discharge from the product discharge line, 21 - discharge from the gas-phase discharge line, 22 - discharge from the cooler, 23 - discharge from the vacuum system.

[0052] When adopting Figure 2 the system shown:

[0053] Feed the crude material feed pipeline (the crude material is crude dicyclopentadiene dioxide material) 1 into the first dissolving kettle A, feed the first protective gas feed pipeline I feed 2 (nitrogen) into the first dissolving kettle A, the tail gas 4 of the first dissolving kettle enters the first condenser B to obtain condensate and return it to the first dissolving kettle A, and the tail gas 5 of the first condenser goes for post-treatment. Feed the circulating material 18 of the liquid phase circulation loop into the first dissolving kettle A, heat up and dissolve it, and obtain the discharge of the first dissolving kettle (dissolved liquid) 3 and enter the first adsorption tower A (NA). NA and NB are in a one-open-one-standby mode. Obtain the discharge of the first adsorption sub-unit 6 and enter the first crystallization kettle C. Cool down and crystallize in the first crystallization kettle C to obtain the primary crystallization material 7 and enter the first centrifuge D. The first centrifuge D is located directly above the second dissolving kettle E. The discharge from the solid phase discharge port of the first centrifuge D 8 enters the second dissolving kettle E, and the discharge from the liquid phase discharge pipeline 9 goes for treatment. Feed nitrogen 13 into the second dissolving kettle E. The tail gas 11 of the second dissolving kettle enters the second condenser F to obtain condensate and return it to the second dissolving kettle E, and the tail gas 12 of the second condenser goes for post-treatment.

[0054] Feed the fresh solvent feed pipeline feed (such as cyclohexane) 10 into the second dissolving kettle E, heat up and dissolve it, and obtain the discharge of the second dissolving kettle (dissolved liquid) 14 and enter the second adsorption tower O (OA). OA and OB are in a one-open-one-standby mode. Obtain the discharge of the second adsorption sub-unit 15 and enter the second crystallization kettle G. Cool down and crystallize in the second crystallization kettle G to obtain the discharge of the second crystallization kettle 16 and enter the second centrifuge H. The second centrifuge H is located directly above the dryer I. The discharge from the solid phase discharge port of the second centrifuge 17 enters the dryer I, and the circulating material 18 of the liquid phase circulation loop circulates to the first dissolving kettle A.

[0055] The dryer I is connected with a protective gas feed pipeline II and a cooler J. The discharge from the product discharge pipeline of the dryer I 20 goes to the product receiving equipment. The gas-phase discharge of the dryer 21 goes to the cooler J, and after cooling, the discharge of the cooler 22 is obtained. The discharge of the cooler 22 is pumped to the vacuum system K to obtain the discharge of the vacuum system 23.

[0056] Among them, the filter connected after the adsorption tower is omitted and not drawn, and the necessary pumps are omitted and not drawn, which does not mean their non-existence. Specific embodiments

[0057] The following specifically describes the present invention in combination with specific embodiments. It is necessary to point out here that the following embodiments are only used for further illustration of the present invention and cannot be understood as limiting the protection scope of the present invention. Some non-essential improvements and adjustments made by those skilled in the art to the present invention based on the content of the present invention still fall within the protection scope of the present invention.

[0058] In addition, it should be noted that all the specific technical features described in the following specific embodiments can be combined in any appropriate manner without conflict. To avoid unnecessary repetition, the present utility model will not further describe various possible combination methods.

[0059] In addition, any combination can be made among various different embodiments of the present utility model as long as it does not violate the idea of the present utility model. The technical solutions thus formed belong to a part of the original public content of this specification and also fall within the protection scope of the present utility model.

[0060] If there is no special limitation on the raw materials used in the examples and comparative examples, they are all disclosed in the prior art. For example, they can be directly purchased or prepared according to the preparation methods disclosed in the prior art.

[0061]

[0062]

Example 1

[0063] Using Figure 1 the refined system shown, taking the raw material containing 19% of α,α-dimethylbenzyl alcohol, 0.1% of acetophenone, 80.40% of dicyclopentadiene dioxide, and 0.50% of other impurities by weight percentage as the solute and feeding it into the first dissolution kettle, then adding the solvent cyclohexane, controlling the pressure with nitrogen, the pressure of the first dissolution kettle being 0.05 MPaG, heating it to 75 °C through the heat medium, completely dissolving the solute to form a solution, and the outlet temperature of the first condenser being 12 °C. The mass ratio of the solvent to the raw material is 5.29. The outlet of the first dissolution kettle is fed into the first adsorption tower for adsorption, the adsorption temperature being 75 °C, the adsorption pressure being 0.05 MPaG, the adsorbent being activated carbon. The first adsorption material is fed into the first crystallization kettle for cooling crystallization, the crystallization temperature being 13 °C, and the pressure being 0.02 MPaG. The primary crystallized material after crystallization is separated by solid-liquid separation using the first centrifuge. The primary crystallized solid phase is transported to the second dissolution kettle through the first feeder, and the primary crystallized mother liquor goes to downstream treatment. Cyclohexane is fed into the second dissolution kettle, heated and dissolved to form a solution, the dissolution temperature being 75 °C, and the pressure being 0.05 MPaG. The outlet temperature of the second condenser is 12 °C. The mass ratio of cyclohexane to the raw material is 5. The outlet of the second dissolution kettle is fed into the second adsorption tower for adsorption, the adsorption temperature being 75 °C, the adsorption pressure being 0.1 MPaG, the adsorbent being activated carbon. The second adsorption material is fed into the second crystallization kettle for cooling crystallization, the crystallization temperature being 13 °C, and the pressure being 0.02 MPaG. The secondary crystallized material after crystallization is separated by solid-liquid separation using the second centrifuge. The secondary crystallized solid phase is transported to the dryer through the second feeder, and the secondary crystallized mother liquor is recycled back to the first dissolution kettle as the solvent.

[0064] The solid phase in the dryer is vacuum-dried to obtain the dicyclopentadiene dioxide product. The vacuum drying temperature is 90 °C and the pressure is 5 kPaA. The outlet temperature of the cooler is 20 °C.

[0065] By weight percentage, the composition of the primary crystallization mother liquor is 91.04% cyclohexane, 3.46% α,α-dimethylbenzyl alcohol, 0.02% acetophenone, and 5.48% dicyclopentadiene dioxide.

[0066] By weight percentage, the composition of the secondary crystallization mother liquor is 94.58% cyclohexane, 0.49% α,α-dimethylbenzyl alcohol, and 4.93% dicyclopentadiene dioxide.

[0067] The product is a white, fluffy solid powder. By weight percentage, the composition of the final product is 0.01% cyclohexane, 0.18% α,α-dimethylbenzyl alcohol, 99.76% dicyclopentadiene dioxide, and 0.05% other impurities. The recovery rate of dicyclopentadiene dioxide is 62.92%.

[0068] The device operates stably without pipeline blockage problems. It is fully enclosed and automatically operated, with no explosion risk.

[0069]

Example 2

[0070] Adopt Figure 1The refined system shown takes raw materials containing 18% α,α-dimethylbenzyl alcohol, 0.2% phenol, 81.30% dicyclopentadiene dioxide, and 0.50% other impurities by weight percentage as solutes and enters the first dissolution kettle. Then cyclohexane is added as a solvent, and the pressure is controlled by nitrogen. The pressure in the first dissolution kettle is 0.05 MPaG, and it is heated to 76 °C by a heat medium. After completely dissolving the solutes, it becomes a solution, and the discharge temperature of the first condenser is 13 °C. The mass ratio of the solvent to the raw materials is 5.80. The discharge from the first dissolution kettle is fed into the first adsorption tower for adsorption. The adsorption temperature is 76 °C, the adsorption pressure is 0.1 MPaG, and the adsorbent is clay. The first adsorbed material is fed into the first crystallization kettle for cooling crystallization. The crystallization temperature is 11 °C, and the pressure is 0.05 MPaG. The primary crystallized material after crystallization is separated by a first centrifuge into solid and liquid phases. The primary crystallized solid phase is transported to the second dissolution kettle by a first feeder, and the primary crystallization mother liquor goes for downstream treatment. Cyclohexane is fed into the second dissolution kettle and heated to dissolve and form a solution. The dissolution temperature is 76 °C, the pressure is 0.05 MPaG, and the discharge temperature of the second condenser is 13 °C. The mass ratio of cyclohexane to the raw materials is 5.5. The discharge from the second dissolution kettle is fed into the second adsorption tower for adsorption. The adsorption temperature is 76 °C, the adsorption pressure is 0.2 MPaG, and the adsorbent is clay. The second adsorbed material is fed into the second crystallization kettle for cooling crystallization. The crystallization temperature is 11 °C, and the pressure is 0.05 MPaG. The secondary crystallized material after crystallization is separated by a second centrifuge into solid and liquid phases. The secondary crystallized solid phase is transported to a dryer by a second feeder, and the secondary crystallization mother liquor is recycled back to the first dissolution kettle as a solvent.

[0071] The solid phase in the dryer is vacuum-dried to obtain a dicyclopentadiene dioxide product. The vacuum drying temperature is 100 °C, and the pressure is 7 kPaA. The discharge temperature of the cooler is 20 °C.

[0072] By weight percentage, the composition of the primary crystallization mother liquor is 91.48% cyclohexane, 3.00% α,α-dimethylbenzyl alcohol, 0.03% phenol, and 5.49% dicyclopentadiene dioxide.

[0073] By weight percentage, the composition of the secondary crystallization mother liquor is 94.91% cyclohexane, 0.36% α,α-dimethylbenzyl alcohol, and 4.73% dicyclopentadiene dioxide.

[0074] The product is a white, fluffy solid powder. By weight percentage, the composition of the final product is 0.01% cyclohexane, 0.08% α,α-dimethylbenzyl alcohol, 99.87% dicyclopentadiene dioxide, and 0.04% other impurities. The recovery rate of dicyclopentadiene dioxide is 59.89%.

[0075] The device operates stably without problems of pipeline blockage. It is fully enclosed and automatically operated, without explosion risk.

[0076]

Example 3

[0077] Using Figure 2 the refined system shown, raw materials containing 21% α,α-dimethylbenzyl alcohol, 0.2% acetophenone, 78.30% dicyclopentadiene dioxide, and 0.50% other impurities by weight percentage enter the first dissolution kettle as solutes, and then cyclohexane is added as a solvent. The pressure in the first dissolution kettle is controlled by nitrogen, with a pressure of 0.05 MPaG. It is heated to 77°C through a heat medium until the solutes are completely dissolved to form a solution, and the outlet temperature of the first condenser is 14°C. The mass ratio of the solvent to the raw materials is 4.06. The discharge from the first dissolution kettle is fed into the first adsorption tower for adsorption, with an adsorption temperature of 77°C and an adsorption pressure of 0.2 MPaG. The adsorbent is clay. The first adsorbed material is fed into the first crystallization kettle for cooling crystallization, with a crystallization temperature of 14°C and a pressure of 0.02 MPaG. The primary crystallized material after crystallization is separated by solid-liquid separation in the first centrifuge. The primary crystallized solid phase enters the second dissolution kettle by gravity difference, and the primary crystallization mother liquor goes for downstream treatment. Cyclohexane is fed into the second dissolution kettle, heated to dissolve and form a solution, with a dissolution temperature of 77°C and a pressure of 0.05 MPaG. The outlet temperature of the second condenser is 14°C. The mass ratio of cyclohexane to the raw materials is 3.8. The discharge from the second dissolution kettle is fed into the second adsorption tower for adsorption, with an adsorption temperature of 77°C and an adsorption pressure of 0.3 MPaG. The adsorbent is activated carbon. The second adsorbed material is fed into the second crystallization kettle for cooling crystallization, with a crystallization temperature of 14°C and a pressure of 0.02 MPaG. The secondary crystallized material after crystallization is separated by solid-liquid separation in the second centrifuge. The secondary crystallized solid phase enters the dryer by gravity difference, and the secondary crystallization mother liquor is recycled back to the first dissolution kettle as a solvent.

[0078] The solid phase in the dryer is dried by nitrogen purging to obtain dicyclopentadiene dioxide product, with a drying temperature of 100°C and a pressure of 5 kPag. The outlet temperature of the cooler is 20°C.

[0079] By weight percentage, the composition of the primary crystallization mother liquor is 89.58% cyclohexane, 4.85% α,α-dimethylbenzyl alcohol, 0.05% acetophenone, and 5.52% dicyclopentadiene dioxide.

[0080] By weight percentage, the composition of the secondary crystallization mother liquor is 93.52% cyclohexane, 0.93% α,α-dimethylbenzyl alcohol, and 5.55% dicyclopentadiene dioxide.

[0081] The product is a white, fluffy solid powder. By weight percentage, the composition of the final product is 0.14% cyclohexane, 0.36% α,α-dimethylbenzyl alcohol, 99.46% dicyclopentadiene dioxide, and 0.04% other impurities. The recovery rate of dicyclopentadiene dioxide is 70.38%.

[0082] The device operates stably without pipeline blockage problems. It is fully enclosed and automatically operated, with no explosion risk.

[0083]

Example 4

[0084] Using Figure 2 the refining system shown, a raw material containing 18.7% α,α-dimethylbenzyl alcohol, 0.2% acetophenone, 0.2% phenol, 80.40% dicyclopentadiene dioxide, and 0.50% other impurities by weight percentage enters the first dissolution kettle as a solute, and then cyclohexane as a solvent is added. The pressure in the first dissolution kettle is controlled by nitrogen, with a pressure of 0.05 MPaG. It is heated to 78 °C through a heat medium, and after completely dissolving the solute to form a solution, the outlet temperature of the first condenser is 12 °C. The mass ratio of the solvent to the raw material is 5.08. The discharge from the first dissolution kettle is fed into the first adsorption tower for adsorption, with an adsorption temperature of 78 °C and an adsorption pressure of 0.3 MPaG. The adsorbent is activated carbon. The first adsorbed material is fed into the first crystallization kettle for cooling crystallization, with a crystallization temperature of 15 °C and a pressure of 0.02 MPaG. The primary crystallized material after crystallization is separated by solid-liquid separation in the first centrifuge. The primary crystallized solid phase enters the second dissolution kettle through a head difference, and the primary crystallization mother liquor goes to downstream treatment. Cyclohexane is fed into the second dissolution kettle, heated and dissolved to form a solution, with a dissolution temperature of 78 °C and a pressure of 0.05 MPaG. The outlet temperature of the second condenser is 12 °C. The mass ratio of cyclohexane to the raw material is 4.8. The discharge from the second dissolution kettle is fed into the second adsorption tower for adsorption, with an adsorption temperature of 78 °C and an adsorption pressure of 0.4 MPaG. The adsorbent is clay. The second adsorbed material is fed into the second crystallization kettle for cooling crystallization, with a crystallization temperature of 15 °C and a pressure of 0.02 MPaG. The secondary crystallized material after crystallization is separated by solid-liquid separation in the second centrifuge. The secondary crystallized solid phase enters the dryer through a head difference, and the secondary crystallization mother liquor is recycled back to the first dissolution kettle as a solvent.

[0085] The solid phase in the dryer is subjected to vacuum drying treatment to obtain a dicyclopentadiene dioxide product. The vacuum drying temperature is 90 °C and the pressure is 10 kPaA. The outlet temperature of the cooler is 20 °C.

[0086] By weight percentage, the composition of the primary crystallization mother liquor is 90.92% cyclohexane, 3.52% α,α-dimethylbenzyl alcohol, 0.04% phenol, 0.04% acetophenone, and 5.48% dicyclopentadiene dioxide.

[0087] By weight percentage, the composition of the secondary crystallization mother liquor is 94.45% cyclohexane, 0.53% α,α-dimethylbenzyl alcohol, and 5.02% dicyclopentadiene dioxide.

[0088] The product is a white, fluffy solid powder. By weight percentage, the composition of the final product is 0.01% cyclohexane, 0.14% α,α-dimethylbenzyl alcohol, 99.83% dicyclopentadiene dioxide, and 0.02% other impurities. The recovery rate of dicyclopentadiene dioxide is 64.43%.

[0089] The device runs smoothly, without any problem of pipeline blockage. It operates automatically in a fully enclosed manner and there is no explosion risk.

[0090] The above has described the present utility model in detail in combination with specific embodiments and exemplary examples. However, these descriptions should not be construed as limitations on the present utility model. Those skilled in the art understand that without departing from the spirit and scope of the present utility model, various equivalent replacements, modifications or improvements can be made to the technical solution and its implementation manner of the present utility model, and all of these fall within the scope of the present utility model. The protection scope of the present utility model is subject to the appended claims.

Claims

1. A dicyclopentadiene dioxide refining system, comprising: one or more dissolution-crystallization-separation units and a drying unit connected in sequence; wherein: Each dissolution-crystallization-separation unit independently and sequentially comprises a dissolution kettle, an adsorption subunit, an optional filtering subunit, a crystallization kettle, a centrifuge and an optional feeder, wherein the feeder is a screw conveyor, each adsorption subunit independently comprises two or more adsorption towers connected in parallel, the drying unit comprises a dryer, and the filtering subunit comprises two or more filters connected in parallel.

2. The refining system according to claim 1, characterized in that: The number of the dissolution-crystallization-separation units is more than two.

3. The refining system according to claim 1, characterized in that: A condenser is independently provided on the top of each dissolving kettle; and / or, a protective gas feed pipeline I and a coarse material feed pipeline are independently provided on each dissolving kettle.

4. The refining system according to claim 1, characterized in that: In each dissolution-crystallization-separation unit: The discharge end of the dissolving kettle is connected to the feed end of the adsorption subunit via a pipeline; and / or, The discharge end of the adsorption subunit is connected to the feed end of the crystallization kettle via a pipeline; and / or, The discharge end of the crystallization kettle is connected to the feed end of the centrifuge through a pipeline.

5. The refining system according to claim 1, characterized in that: The centrifuge is provided with a liquid phase discharge port and a solid phase discharge port, wherein the liquid phase discharge port is provided with a liquid phase external discharge pipeline, and the solid phase discharge port is connected to the feed end of the feeder or the feed end of the dissolution kettle of the next dissolution-crystallization-separation unit or the feed end of the drying unit through a pipeline.

6. The refining system according to claim 1, characterized in that: The drying unit comprises a dryer and a cooler, and the dryer is provided with a protective gas feed pipeline II, a product discharge pipeline and a gas phase discharge pipeline.

7. The refining system according to claim 6, characterized in that The cooler is arranged on the gas phase discharge pipeline.

8. The refining system according to claim 1, characterized in that: The system further optionally comprises a vacuum unit connected to the drying unit.

9. The refining system according to any one of claims 1 to 8, characterized in that: Along the material flow direction, the liquid phase discharge port of the centrifuge in the last dissolution-crystallization-separation unit is connected to the feed end of the dissolution kettle in the first dissolution-crystallization-separation unit through a liquid phase circulation loop.

10. The refining system according to claim 9, characterized in that The filtering subunit is arranged between the adsorption subunit and the crystallization kettle.

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