Cyclopentane refining system and refining method thereof

Abstract

The refining method comprises the following steps: crude cyclopentene is subjected to a light component removal process and a cyclopentene refining process to obtain refined cyclopentene, and then the refined cyclopentene is subjected to a full hydrogenation process and an extractive distillation process to obtain refined cyclopentane. Compared with a domestic existing process technical route, a liquid material enters from the upper part of a full hydrogenation reactor, hydrogen enters from four sides of an upper sealing head of the reactor, and then the liquid material is fully mixed with the hydrogen and the liquid material at the upper part of the reactor to complete mass transfer and then enters a catalyst bed layer. According to the process route, the utilization category of the raw materials is improved, meanwhile, the product quality is improved, and compared with existing domestic process technical routes, the process route is more suitable for industrial production and has high social use value and application prospects.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical engineering, and particularly relates to a cyclopentane refining system and a refining method thereof. Background Art

[0002] Cyclopentane is an important organic chemical raw material for producing refrigerants and foaming agents. Since it does not damage the ozone layer, it has currently replaced chlorofluorocarbons and is widely used in the freezer, refrigerator, and refrigeration insulation industries, with broad market prospects. Cyclopentane can be used as a new foaming agent for rigid polyurethane foam and can also be used to replace chlorofluorocarbons (CFCS) that damage the atmospheric ozone layer. It is now widely used in the production of fluorine-free refrigerators, freezers, cold storage, pipeline insulation, and other fields.

[0003] Cyclopentane widely exists in the C5 fraction. The C5 fraction is a by-product in the reforming unit and ethylene cracking process of refineries. The C5 by-product from ethylene can obtain n-pentane, isopentane, and cyclopentane through catalytic hydrogenation and separation processes; while the C5-depleted oil from the reforming unit contains a large amount of n-pentane, isopentane, and cyclopentane, and cyclopentane can be obtained only through the separation process. However, 2,2-dimethylbutane has a great influence on the purity of cyclopentane. The boiling points of cyclopentane and 2,2-dimethylbutane are close (under normal pressure), with cyclopentane being 49.25°C and 2,2-dimethylbutane being 49.74°C, a difference of 0.49°C. The two are not only a near-boiling system but also an azeotropic system, with an azeotropic point of 49.4°C. Conventional distillation methods cannot obtain high-purity cyclopentane, and only azeotropic distillation or extractive distillation methods can be used.

[0004] Currently, the methods for producing cyclopentane are roughly divided into two categories: the first category is to separate cyclopentane from the mixture, and the second category is to produce it by hydrogenating cyclopentadiene. The first method for producing cyclopentane is a more common method. However, due to the close boiling points of 2,2-dimethylbutane and cyclopentane in the mixture, it is difficult to separate them. The purity of the cyclopentane product obtained by ordinary distillation is difficult to reach more than 99.8%. Moreover, when the content of 2,2-dimethylbutane is relatively high, the mass fraction of cyclopentane will even be less than 95%, which does not meet the cyclopentane quality index in "Industrial Cyclopentane" GB / T 18825-2002.

[0005] There have been research reports in China on the hydrogenation of cyclopentadiene to prepare cyclopentane, but there is no mention of using the bottom material of the cyclopentene product tower for hydrogenation reaction to prepare cyclopentane; there have been research reports in China on the method of separating cyclopentane and neohexane by extractive distillation process, but it has not been mentioned that the cyclopentane / neohexane mixed system is obtained by the hydrogenation reaction of cyclopentene. Summary of the Invention

[0006] In order to solve the problems mentioned in the above background art, the present invention provides a cyclopentane refining system and a refining method thereof.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A method for refining cyclopentane, comprising the following steps:

[0009] S1 Light component removal process:

[0010] The crude cyclopentene material enters the light component removal tower and is continuously rectified. The operating pressure is controlled at 0.04 - 0.06 MPa, the bottom temperature of the tower is controlled at 55 - 70 °C, the top temperature of the tower is controlled at 55 - 70 °C. The material discharged from the bottom of the tower is the treated crude cyclopentene, which goes to the cyclopentene refining process. The non-condensable gas at the top of the tower is sent to the "incinerator incineration" waste gas treatment system for treatment and then discharged. The main product at the top of the tower is solvent oil, which is sent to the light hydrocarbon solvent oil storage tank.

[0011] S2 Cyclopentene refining process:

[0012] The crude cyclopentene material after light component removal is pumped to the cyclopentene rectification tower and is continuously rectified. The operating pressure is controlled at 0.04 - 0.06 MPa, the bottom temperature of the tower is controlled at 55.6 - 62.4 °C, the top temperature of the tower is controlled at 55.6 - 62.4 °C. The product discharged from the top of the tower is the finished cyclopentene product. The non-condensable gas at the top of the tower is sent to the "incinerator incineration" waste gas treatment system for treatment and then discharged. The material at the bottom of the tower is the crude cyclopentane material containing a small amount of cyclopentene, which is pumped to the full hydrogenation process for the full hydrogenation process.

[0013] The crude cyclopentane material is processed through processes such as hydrogenation, extractive distillation, and desorption to obtain the product cyclopentene.

[0014] S3 Full hydrogenation process:

[0015] The crude cyclopentane material enters the hydrogenation material buffer tank, and then is pumped to the hydrogenation preheater to be heated to 160 - 220 °C. The heated crude cyclopentane material and hydrogen enter the mixer and are mixed and then enter the hydrogenation reactor for full hydrogenation, flowing in from the top and out from the bottom, with an excessive amount of hydrogen. The bed temperature of the hydrogenation catalyst is controlled not to exceed 260 °C, and the liquid-phase volume space velocity is controlled at 1.0 h -1 , the system pressure is controlled at 2.8 MPa, and the hydrogen-oil ratio is controlled at 2.0 - 8.0. Before the reaction starts, the catalyst is activated with high-temperature hydrogen, and the high temperature is controlled at 400 - 650 °C.

[0016] After full hydrogenation, cyclopentane containing a small amount of other C5 impurities and unreacted hydrogen are obtained. After passing through the hydrogenation reaction effluent cooler, they are separated in the hydrogenation material gas-liquid separation tank. The liquid material after gas-liquid separation (cyclopentane containing a small amount of other C5 impurities) is controlled by a liquid level regulating valve and enters the buffer tank for the material after hydrogenation, and then is pumped to the extractive distillation process by a pump. The gas after gas-liquid separation (recycled hydrogen) enters the hydrogen recycling and pressurizing system. After secondary gas-liquid separation and compression by a hydrogen compressor, it returns to the feed for recycling. The liquid phase after secondary gas-liquid separation returns to the full hydrogenation feed tank for recovery. The hydrogen-containing tail gas generated in the buffer tank for the material after hydrogenation is sent to the "incinerator for incineration" waste gas treatment system for treatment and then discharged. Waste hydrogenation catalyst is regularly generated during the reaction process. The waste hydrogenation catalyst is temporarily stored in the hazardous waste warehouse of the factory area and then regularly entrusted to a qualified unit for disposal.

[0017] S4 Extractive distillation process:

[0018] The above hydrogenation reaction liquid and extractant enter the extractive distillation column for continuous extractive distillation respectively. The operating pressure is controlled at 0.002 MPa, the operating temperature at the top of the column is controlled at 49.6 - 81.6 °C, the operating temperature at the bottom of the column is 49.6 - 81.6 °C. The bottom product component is the extractant containing cyclopentane, which is pumped to the desorption column for separation of cyclopentane and extractant. The non-condensable gas at the top of the column is sent to the "incinerator for incineration" waste gas treatment system for treatment and then discharged. The main product obtained at the top of the column is solvent oil, which is sent to the light hydrocarbon solvent oil storage tank.

[0019] S5 Desorption process:

[0020] The bottom liquid of the above extractive distillation column enters the desorption column for continuous distillation. The operating pressure is controlled at 0.05 MPa, the top temperature is controlled at 52.3 - 158.1 °C. The cyclopentane product distilled out is directly sold. The non-condensable gas at the top of the column is sent to the "incinerator for incineration" waste gas treatment system for treatment and then discharged; the bottom temperature is controlled at 52.3 - 158.1 °C, and the bottom product component is the recycled extractant, which is returned to the extractive distillation column for recycling after heat exchange.

[0021] S6 Extractant refining process:

[0022] The recycled extractant at the bottom of the above desorption column needs to be purified after circulating for a period of time. The bottom liquid is pumped to the extractant refining column for vacuum distillation through a pipeline branch by a bottom pump. The operating pressure is controlled at -0.09 MPa, the top temperature is controlled at 82.8 - 94.6 °C. The extractant is evaporated from the top of the column and pumped to the extractant feed buffer tank for standby. The non-condensable gas at the top of the column is sent to the "incinerator for incineration" waste gas treatment system for treatment and then discharged; the bottom temperature is controlled at 82.8 - 94.6 °C, and the bottom product component is mainly heavy components, which are sent to the incinerator for incineration.

[0023] Preferably, the hydrogenation catalyst is a Raney nickel catalyst.

[0024] Preferably, the extractant is N, N-dimethylformamide.

[0025] A cyclopentane refining system includes a light component removal unit, a cyclopentene refining unit, a full hydrogenation unit, an extractive distillation unit, a desorption unit, and an extractant refining unit. The crude cyclopentene material enters the light component removal tower in the light component removal unit and is continuously distilled. After that, the crude cyclopentene material is pumped to the cyclopentene distillation tower in the cyclopentene refining unit for continuous distillation.

[0026] The bottom material of the tower is the crude cyclopentane material containing a small amount of cyclopentene, which is pumped to the full hydrogenation unit for the full hydrogenation process. The crude cyclopentane material enters the hydrogenation material buffer tank and is then pumped to the hydrogenation preheater for heating. The heated crude cyclopentane material and hydrogen enter the mixer at the same time, and after mixing, they enter the hydrogenation reactor for full hydrogenation.

[0027] After full hydrogenation, cyclopentane containing a small amount of other C5 impurities and unreacted hydrogen are obtained. After passing through the hydrogenation reaction effluent cooler, they enter the hydrogenation material gas-liquid separation tank for separation. The liquid material after gas-liquid separation is controlled by the liquid level regulating valve to enter the buffer tank for the material after hydrogenation, and then is pumped to the extractive distillation unit.

[0028] The above-mentioned hydrogenation reaction liquid and extractant enter the extractive distillation tower for continuous extractive distillation respectively. The bottom discharge component is the extractant containing cyclopentane, which is pumped to the desorption tower for the separation of cyclopentane and extractant, and the refined cyclopentane is obtained through distillation.

[0029] The circulating extractant at the bottom of the above-mentioned desorption tower needs to be purified after circulating for a period of time. The bottom liquid is pumped to the extractant refining tower through the pipeline branch by the bottom pump for vacuum distillation. The extractant is evaporated from the top of the tower and is pumped to the extractant feed buffer tank for standby.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] Compared with the existing domestic process technology route, in this application, the liquid material enters from the upper part of the full hydrogenation reactor, and hydrogen enters from the four sides of the upper head of the reactor. Then, after the hydrogen and the liquid material are fully mixed in the upper part of the reactor to complete mass transfer, they enter the catalyst bed layer. The process route of this application improves the utilization category of raw materials and at the same time improves the product quality. Compared with the existing domestic process technology route, it is more suitable for industrial production and has high social use value and application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0033] Figure 1 This is a schematic diagram of the technological process of the present invention. Specific embodiments

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0035] Embodiment 1

[0036] Refer to Figure 1 , a method for refining cyclopentane, comprising the following steps:

[0037] S1 Light component removal process:

[0038] The crude cyclopentene material enters the light component removal column and is continuously rectified. The operating pressure is controlled at 0.06 MPa, the bottom temperature of the column is controlled at 60 °C, the top temperature of the column is controlled at 70 °C. The material discharged from the bottom of the column is the treated crude cyclopentene, which goes to the cyclopentene refining process. The non-condensable gas at the top of the column is sent to the "incinerator incineration" waste gas treatment system for treatment and then discharged. The main product at the top of the column is solvent oil, which is sent to the light hydrocarbon solvent oil storage tank.

[0039] S2 Cyclopentene refining process:

[0040] The crude cyclopentene material after light component removal is pumped to the cyclopentene rectification column and continuously rectified. The operating pressure is controlled at 0.04 MPa, the bottom temperature of the column is controlled at 60 °C, the top temperature of the column is controlled at 62.4 °C. The product discharged from the top of the column is the finished cyclopentene product. The non-condensable gas at the top of the column is sent to the "incinerator incineration" waste gas treatment system for treatment and then discharged. The material at the bottom of the column is the crude cyclopentane material containing a small amount of cyclopentene, which is pumped to the full hydrogenation process for the full hydrogenation process.

[0041] The crude cyclopentane material is obtained as the product cyclopentene through processes such as hydrogenation, extractive distillation, and desorption.

[0042] S3 Full hydrogenation process:

[0043] The crude cyclopentane material enters the hydrogenation material buffer tank, and then is pumped to the hydrogenation preheater and heated to 180 °C. The heated crude cyclopentane material and hydrogen enter the mixer at the same time, and then enter the hydrogenation reactor for full hydrogenation, flowing in from the top and out from the bottom. The hydrogen is in excess, and the bed temperature of the Raney nickel catalyst is controlled not to exceed 260 °C. The liquid-phase volume space velocity is controlled at 1.0 h -1, the system pressure is controlled at 2.8 MPa, the hydrogen-oil ratio is controlled at 2.0, and the catalyst is activated with high-temperature hydrogen before the reaction starts, with the high temperature controlled at 600 °C.

[0044] After full hydrogenation, cyclopentane containing a small amount of other C5 impurities and unreacted hydrogen are obtained. After passing through the hydrogenation reaction product cooler, they enter the hydrogenation material gas-liquid separation tank for separation. The liquid material after gas-liquid separation (cyclopentane containing a small amount of other C5 impurities) is controlled by a level regulating valve to enter the buffer tank for hydrogenated materials, and then is pumped to the extractive distillation process by a pump. The gas after gas-liquid separation (recycled hydrogen) enters the hydrogen recycling and pressurizing system. After secondary gas-liquid separation and compression by a hydrogen compressor, it returns to the feed for recycling. The liquid phase of the secondary gas-liquid separation returns to the full hydrogenation feed tank for recovery. The hydrogen-containing tail gas generated in the buffer tank for hydrogenated materials is sent to the "incinerator for incineration" waste gas treatment system for treatment and then discharged. Spent hydrogenation catalyst is periodically generated during the reaction process. The spent hydrogenation catalyst is temporarily stored in the hazardous waste warehouse of the factory area and then periodically entrusted to a qualified unit for disposal.

[0045] S4 Extractive distillation process:

[0046] The above hydrogenation reaction liquid and the extractant N, N-dimethylformamide enter the extractive distillation column for continuous extractive distillation respectively. The operating pressure is controlled at 0.002 MPa, the operating temperature at the top of the column is controlled at 55 °C, and the operating temperature at the bottom of the column is 81.6 °C. The bottom discharge component is the extractant containing cyclopentane, which is pumped to the desorption column for separation of cyclopentane and the extractant. The non-condensable gas at the top of the column is sent to the "incinerator for incineration" waste gas treatment system for treatment and then discharged. The main product obtained at the top of the column is solvent oil, which is sent to the light hydrocarbon solvent oil storage tank.

[0047] S5 Desorption process:

[0048] The bottom liquid of the above extractive distillation column enters the desorption column for continuous distillation. The operating pressure is controlled at 0.05 MPa, the top temperature is controlled at 158.1 °C. The cyclopentane product distilled out is directly sold. The non-condensable gas at the top of the column is sent to the "incinerator for incineration" waste gas treatment system for treatment and then discharged; the bottom temperature is controlled at 158.1 °C, and the discharge component is the recycled extractant, which is returned to the extractive distillation column for recycling after heat exchange.

[0049] S6 Extractant refining process:

[0050] The recycled extractant at the bottom of the above desorption column needs to be purified after circulating for a period of time. The bottom liquid is pumped to the extractant refining column for vacuum distillation through a pipeline branch by a bottom pump. The operating pressure is controlled at -0.09 MPa, and the top temperature is controlled at 94.6 °C. The extractant is evaporated from the top of the column and pumped to the extractant feed buffer tank for standby. The non-condensable gas at the top of the column is sent to the "incinerator for incineration" waste gas treatment system for treatment and then discharged; the bottom temperature is controlled at 82.8 °C, and the discharge component is mainly heavy components, which are sent to the incinerator for incineration.

[0051] Example 2

[0052] The difference between this example and Example 1 is that the hydrogen-oil ratio is controlled at 3.0, and the structures not described are referred to Example 1.

[0053] Example 3

[0054] The difference between this example and Example 1 is that the hydrogen-oil ratio is controlled at 4.0, and the structures not described are referred to Example 1.

[0055] Example 4

[0056] The difference between this example and Example 1 is that the hydrogen-oil ratio is controlled at 6.0, and the structures not described are referred to Example 1.

[0057] Example 5

[0058] The difference between this example and Example 1 is that the hydrogen-oil ratio is controlled at 8.0, and the structures not described are referred to Example 1.

[0059] Example 6

[0060] The difference between this example and Example 3 is that the heating temperature is controlled at 160 °C.

[0061] Example 7

[0062] The difference between this example and Example 3 is that the heating temperature is controlled at 170 °C.

[0063] Example 8

[0064] The difference between this example and Example 3 is that the heating temperature is controlled at 180 °C.

[0065] Example 9

[0066] The difference between this example and Example 3 is that the heating temperature is controlled at 190 °C.

[0067] Example 10

[0068] The difference between this example and Example 3 is that the heating temperature is controlled at 200 °C.

[0069] Example 11

[0070] The difference between this example and Example 3 is that the heating temperature is controlled at 210 °C.

[0071] Example 12

[0072] The difference between this example and Example 3 is that the heating temperature is controlled at 220 °C.

[0073] Table 1: Conversion rate and content change of cyclopentene under different hydrogen-oil ratios

[0074]

[0075] Table 2: Changes in the content and conversion rate of cyclopentene at different temperatures (hydrogen-oil ratio: 4.0)

[0076] Test item Cyclopentene (%) Conversion rate of cyclopentene (%) Example 6 0.88 94.14 Example 7 0.17 98.87 Example 8 0.02 99.87 Example 9 0.013 99.91 Example 10 0.01 99.93 Example 11 0.02 99.87 Example 12 0.01 99.93

[0077] It can be seen from Table 1 that as the hydrogen-oil ratio increases, the conversion rate of cyclopentene shows a trend of first increasing and then decreasing. When the hydrogen-oil ratio is 4.0, the conversion rate of cyclopentene reaches the highest at 99.87%, and then continuing to increase the hydrogen-oil ratio, the conversion rate will slightly decrease. As the hydrogen-oil ratio rises, the flow rate of hydrogen also increases, and the raw material can be more fully mixed and contacted with hydrogen, so that the hydrogenation reaction occurs between cyclopentene and hydrogen. At the same time, the increase in the hydrogen flow rate will also promote the forward reaction and improve the conversion rate. When the hydrogen-oil ratio is further increased, at this time the hydrogen flow rate is too large, which may cause the residence time of hydrogen and cyclopentene in the raw material on the catalyst to be too short, and the reaction time is short, resulting in a decrease in the conversion rate.

[0078] It can be known from Table 2 that when the experimental heating temperature range is 160 - 220 °C, the liquid-phase volume space velocity is 1.0 h -1; the hydrogen-oil ratio is 4.0; the reaction pressure is 2.8 MPa. As the temperature increases, the reaction rate accelerates, and the conversion rate of cyclopentene also gradually increases. The increase in temperature will increase the percentage of active molecules in the reaction, and the increased molecular movement speed makes the collisions between molecules more frequent and effective, further promoting the progress of the reaction. When the heating temperature is in the range of 160 - 220 °C, the conversion rate of cyclopentene shows a trend of first increasing and then leveling off. When the heating temperature reaches 190 °C, the conversion rate of cyclopentene can reach 99.9%.

[0079] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A method for refining cyclopentane, characterized in that: The following steps are involved: S1 lightening process: The crude cyclopentene material enters the light-removal tower for continuous distillation, the operating pressure is controlled at 0.04-0.06MPa, the tower bottom temperature is controlled at 55-70°C, the tower top temperature is controlled at 55-70°C, and the crude cyclopentene discharged from the tower bottom is treated and refined by removing cyclopentene; S2 Cyclopentene Refining Process: The crude cyclopentene material after light removal is pumped to the cyclopentene distillation tower for continuous distillation. The operating pressure is controlled at 0.04-0.06MPa, the tower bottom temperature is controlled at 55.6-62.4℃, the tower top temperature is controlled at 55.6-62.4℃, and the cyclopentene product is obtained by discharging the material from the tower top. S3 full hydrogenation process: The crude cyclopentane material enters the hydrogenation material buffer tank, and then is pumped to the hydrogenation preheater to be heated to 160-220°C. The heated crude cyclopentane material and hydrogen enter the mixer at the same time and then enter the hydrogenation reactor for full hydrogenation. The hydrogen is in and out from the top, with excess hydrogen. The bed temperature of the hydrogenation catalyst is controlled not to exceed 260°C, and the liquid phase volume space velocity is controlled at 1.0h -1 , the system pressure is controlled at 2.8MPa, the hydrogen-to-oil ratio is controlled at 2.0-8.0, and the catalyst is activated with high-temperature hydrogen before the reaction begins, and the high temperature is controlled at 400-650℃; After full hydrogenation, cyclopentane containing a small amount of other C5 impurities and unreacted hydrogen are obtained, which are separated in the hydrogenation material gas-liquid separation tank after passing through the hydrogenation reaction discharge cooler. The liquid material after gas-liquid separation is controlled by the liquid level regulating valve to enter the hydrogenation material buffer tank, and then pumped to the extraction distillation process; S4 extraction and distillation process: The hydrogenation reaction liquid and the extractant are respectively fed into an extractive distillation tower for continuous extractive distillation, the operating pressure is controlled at 0.002 MPa, the tower top operating temperature is controlled at 49.6-81.6°C, the tower bottom operating temperature is 49.6-81.6°C, the tower bottom discharge component is an extractant containing cyclopentane, which is pumped to a desorption tower for separation of cyclopentane and the extractant; S5 desorption process: The bottom liquid of the extractive distillation tower enters the desorption tower for continuous distillation, the operating pressure is controlled at 0.05MPa, the tower top temperature is controlled at 52.3-158.1℃, and the cyclopentane product is distilled out and sold directly; S6 Extractant Refining Process: The extractant circulating in the bottom of the desorption tower needs to be cleaned after circulating for a period of time. The bottom liquid is pumped to the extractant refining tower through the pipeline branch line and the bottom pump to carry out vacuum distillation. The operating pressure is controlled at -0.09MPa and the top temperature is controlled at 82.8-94.6℃. The extractant is evaporated from the top of the tower and pumped to the extractant feed buffer tank for standby use.

2. A cyclopentane refining method according to claim 1, characterized in that: In the S1 light removal process, the non-condensable gas at the top of the tower is passed into the "incineration incinerator" waste gas treatment system for treatment and then discharged; the solvent oil is mainly obtained at the top of the tower, and the solvent oil is sent to the light hydrocarbon solvent oil storage tank.

3. A cyclopentane refining method according to claim 1, characterized in that: In the S2 cyclopentene refining process, the non-condensable gas at the top of the tower is introduced into the "incineration in the incinerator" waste gas treatment system for treatment and then discharged; the tower bottom material is a crude cyclopentane material containing a small amount of cyclopentene, which is pumped to the full hydrogenation process for full hydrogenation.

4. A cyclopentane refining method according to claim 1, characterized in that: The circulating hydrogen after gas-liquid separation in the S3 full hydrogenation process enters the hydrogen circulation pressurization system, and is returned to the feed for circulation after secondary gas-liquid separation and compression by the hydrogen compressor. The liquid phase of the secondary gas-liquid separation is returned to the full hydrogenation feed tank for recovery. The hydrogen-containing tail gas generated in the material buffer tank after hydrogenation is passed into the "incineration incinerator" waste gas treatment system for treatment and then discharged; waste hydrogenation catalysts are regularly generated during the reaction process, and the waste hydrogenation catalysts are temporarily stored in the hazardous waste warehouse in the factory area and then regularly entrusted to qualified units for disposal.

5. A cyclopentane refining method according to claim 1, characterized in that: In the S4 extraction and distillation process, the non-condensable gas at the top of the tower is passed into the "incineration incinerator" waste gas treatment system for treatment and then discharged; the solvent oil is mainly obtained at the top of the tower, and the solvent oil is sent to the light hydrocarbon solvent oil storage tank.

6. A cyclopentane refining method according to claim 1, characterized in that: In the S5 desorption process, the non-condensable gas at the top of the tower is introduced into the "incineration incinerator" waste gas treatment system for treatment and then discharged; the temperature of the tower bottom is controlled at 52.3-158.1°C, and the discharge component is a circulating extractant, which is returned to the extraction distillation tower for recycling after heat exchange.

7. A cyclopentane purification method according to claim 1, characterized in that: In the S6 extractant refining process, the non-condensable gas at the top of the tower is passed into the "incineration incinerator" waste gas treatment system for treatment and then discharged; the temperature of the tower bottom is controlled at 82.8-94.6°C, and the discharge component is mainly heavy components, which are sent to the incinerator for incineration.

8. A cyclopentane purification method according to claim 1, characterized in that: The hydrogenation catalyst is a Raney nickel catalyst.

9. A cyclopentane purification method according to claim 1, characterized in that: The extractant is N,N-dimethylformamide.

10. A cyclopentane refining system, characterized in that: It includes light removal unit, cyclopentene refining unit, full hydrogenation unit, extractive distillation unit, desorption unit and extractant refining unit; The crude cyclopentene material enters the light removal tower in the light removal unit, and after continuous distillation, the crude cyclopentene material is pumped to the cyclopentene distillation tower in the cyclopentene refining unit for continuous distillation; The bottom material is a crude cyclopentane material containing a small amount of cyclopentene, which is pumped to the full hydrogenation unit for full hydrogenation process. The crude cyclopentane material enters the hydrogenation material buffer tank and is then pumped to the hydrogenation preheater for heating. The heated crude cyclopentane material and hydrogen enter the mixer at the same time and are mixed before entering the hydrogenation reactor for full hydrogenation. After full hydrogenation, cyclopentane containing a small amount of other C5 impurities and unreacted hydrogen are obtained, which are separated in the hydrogenation material gas-liquid separation tank after passing through the hydrogenation reaction discharge cooler. The liquid material after gas-liquid separation is controlled by the liquid level regulating valve to enter the hydrogenation material buffer tank, and then pumped to the extraction distillation unit; The hydrogenation reaction liquid and the extractant are respectively fed into an extractive distillation tower for continuous extractive distillation, and the discharge component of the tower bottom is an extractant containing cyclopentane, which is pumped to a desorption tower for separation of cyclopentane and the extractant, and the finished cyclopentane is obtained by distillation; The extractant circulating in the bottom of the desorption tower needs to be cleaned after circulating for a period of time. The bottom liquid is pumped to the extractant refining tower through a pipeline branch line and then subjected to vacuum distillation. The extractant is evaporated from the top of the tower and pumped to the extractant feed buffer tank for standby use.

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