Method for synthesizing cyclopentane through cracking of dicyclopentadiene and hydrogenation of cyclopentadiene

Abstract

The preparation method comprises the following steps: S1, carrying out cracking reaction on a dicyclopentadiene raw material and a catalyst in a reactor to obtain a cracking product; s2, carrying out water removal and propane removal treatment on the cracking product to obtain cyclopentadiene; s3, carrying out hydrogenation reaction on the cyclopentadiene at the temperature of 140 DEG C to 150 DEG C under the pressure of 0.3 MPa to 0.4 MPa in the presence of a catalyst; wherein the mass ratio of the hydrogen to the cyclopentadiene is 1.0 to 4.0. The method does not need to independently introduce a solvent, avoids a solvent removal process, and has the advantages of few byproducts and high conversion rate.

Description

Technical Field

[0001] The invention relates to the technical field of chemical raw material preparation, in particular to a method for synthesizing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene. Background Art

[0002] As an important chemical raw material, cyclopentane has important uses in the fields of foaming agent, refrigerant, rubber synthesis, gasoline, etc. The domestic production route for preparing cyclopentane products using cyclopentene as the main raw material is to prepare cyclopentanol by hydrogenation of cyclopentadiene through anti-Markovnikov addition, and then prepare cyclopentane by dehydrogenation of cyclopentanol. This process route is relatively long. During the reaction process, the dehydrogenation of cyclopentanol has high requirements on equipment and greatly increases the cost of the device. At the same time, due to the presence of unsaturated double bonds in cyclopentadiene, it is easy to cause the generation of by-products and coking, which leads to poor continuous production performance of the equipment. At the same time, during the dehydrogenation of cyclopentanol, the conversion rate is generally only 25%, and the energy consumption is high.

[0003] There is no precedent in China for preparing cyclopentane from dicyclopentadiene (DCPD). A method for preparing cyclopentadiene (CPD) by cracking dicyclopentadiene (DCPD) and hydrogenating cyclopentadiene (CPD) to prepare cyclopentane is disclosed. This method utilizes direct hydrogenation of CPD, has a high conversion rate, and does not cause a large number of side reactions. At the same time, the conversion rate of CPD is high.

[0004] 1. The existing process route for preparing cyclopentane products using cyclopentene as the main raw material is long, the equipment requirements are high, and the equipment cost increases significantly. 2. Due to the presence of unsaturated double bonds, cyclopentadiene is prone to the formation of by-products and coking, resulting in poor continuous production performance of the equipment. 3. In the dehydrogenation process of cyclopentanol, the conversion rate is generally only 25%, and the energy consumption is high. 4. In the existing technology, there are many by-products in the reaction process and the conversion rate is low. Summary of the invention

[0005] The main purpose of the present invention is to overcome the defects of the existing dicyclopentadiene cracking and cyclopentadiene hydrogenation synthesis of cyclopentane and the preparation method thereof, and to provide a new dicyclopentadiene cracking and cyclopentadiene hydrogenation synthesis of cyclopentane and the preparation method thereof. The technical problem to be solved is that it does not need to introduce a solvent separately, and the cyclopentadiene generated in the preparation process is directly used as a solvent, no by-products are generated, and the conversion rate is high, so that it is more suitable for practical use and has industrial utilization value.

[0006] Compared with the prior art, the present invention has obvious advantages and beneficial effects. From the above technical scheme, it can be seen that in order to achieve the above-mentioned invention purpose, the main technical contents of the present invention are as follows:

[0007] In one aspect, the present invention provides a method for synthesizing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene, comprising:

[0008] S1, performing a cracking reaction on a dicyclopentadiene raw material and a catalyst in a reactor to obtain a cracking product;

[0009] S2, removing water and propane from the cracking product to obtain cyclopentadiene;

[0010] S3, hydrogenating the cyclopentadiene at a temperature of 140° C. to 150° C. and a pressure of 0.3 to 0.4 MPa in the presence of a catalyst;

[0011] Wherein, the mass ratio of hydrogen to cyclopentadiene is 1.0 to 4.0.

[0012] In an optional embodiment, the dehydration and propane removal treatment of the cracking product in step S2 includes: distilling the cracking product through a depropanizing distillation tower;

[0013] The distillation conditions are as follows: the tower top pressure is 0.90MPa-0.95MPa, the tower bottom temperature is 125°C-128°C, and the reflux ratio is 1.0.

[0014] In an optional embodiment, the distillation tower has 5 to 18 plates.

[0015] In an optional embodiment, in step S2, the propane removal distillation temperature for removing water and propane from the cracking product is 43°C to 46°C, and the distillation temperature for the cyclopentadiene and cyclopentane mixture is 44°C to 46°C.

[0016] In an optional embodiment, the particle size of the catalyst is 20 mesh to 100 mesh.

[0017] In an optional embodiment, the hydrogenation time is 5 to 20 hours.

[0018] In an optional embodiment, the catalyst is selected from any one or more of Ni, Cu, Al, Pt, and Pd supported on alumina.

[0019] In an optional embodiment, the catalyst particle size is 20 mesh to 40 mesh.

[0020] On the other hand, a cyclopentane is provided, wherein the cyclopentane is prepared by any of the above-mentioned methods for synthesizing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene.

[0021] As can be seen from the above, the present invention is about a dicyclopentadiene cracking cyclopentadiene hydrogenation synthesis of cyclopentane and a preparation method thereof, including: S1, dicyclopentadiene raw material and catalyst are subjected to cracking reaction in a reactor to obtain cracking products; S2, the cracking products are subjected to water removal and propane removal treatment to obtain cyclopentadiene; S3, the cyclopentadiene is subjected to hydrogenation reaction, the hydrogenation reaction temperature is 140 ℃ ~ 150 ℃, the pressure is 0.3 ~ 0.4MPa, and the hydrogenation reaction is carried out in the presence of a catalyst, wherein the present invention does not need to add a solvent separately, and the cyclopentadiene obtained in the S2 step is directly used as a solvent; wherein the mass ratio of hydrogen to cyclopentadiene is 1.0 ~ 4.0. The present invention does not need to introduce a solvent separately, and directly uses the cyclopentadiene produced in the preparation process as a solvent, produces less by-products, is easy to separate, is simple to operate, and has a high conversion rate.

[0022] The method provided by the embodiment of the present invention has at least the following beneficial effects:

[0023] By step S1, dicyclopentadiene raw material and catalyst are subjected to cracking reaction in a reactor to obtain cracking products; the cracking products include cyclopentadiene, water and propane, and the cracking products are treated with water and propane removal by step S2 to obtain cyclopentadiene; by step S3, cyclopentadiene is subjected to hydrogenation reaction, the hydrogenation reaction temperature is 140 ℃~150 ℃, the pressure is carried out at 0.3~0.4MPa, and the hydrogenation reaction is carried out in the presence of a catalyst, wherein the solvent used for hydrogenation is the cyclopentadiene obtained in step S2, and since the boiling point of cyclopentadiene itself is not high (41.5 ℃), it can be used as a solvent, and in the process of synthesizing cyclopentane by cracking cyclopentadiene from dicyclopentadiene, it is not considered to add other solvents, and the treatment of the newly added solvent in the subsequent steps is avoided, and the yield and purity of the product are improved. The method provided by the embodiment of the present invention has a short process route, does not require very high equipment requirements, and reduces the cost of equipment. Furthermore, the present invention does not need to introduce a solvent separately, and directly uses the cyclopentadiene produced in the preparation process as the solvent, does not produce by-products, and has a high conversion rate.

[0024] In summary, the special dicyclopentadiene cracking cyclopentadiene hydrogenation synthesis of cyclopentane and its preparation method of the present invention do not need to introduce a solvent separately, directly use the cyclopentadiene produced in the preparation process as a solvent, do not produce by-products, and have a high conversion rate. It has the above-mentioned advantages and practical value, and no similar design is publicly published or used in the similar dicyclopentadiene cracking cyclopentadiene hydrogenation synthesis of cyclopentane and its preparation method, and it is indeed innovative. It has great improvements in both dicyclopentadiene cracking cyclopentadiene hydrogenation synthesis of cyclopentane and its preparation method or in function, and has great progress in technology, and has produced easy-to-use and practical effects, and has a plurality of enhanced effects than the existing dicyclopentadiene cracking cyclopentadiene hydrogenation synthesis of cyclopentane and its preparation method, so that it is more suitable for practical use, and has a wide range of industrial utilization value, and is truly a novel, progressive, and practical new design.

[0025] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings.

[0026] The specific dicyclopentadiene cracking and cyclopentadiene hydrogenation synthesis of cyclopentane and the preparation method thereof are described in detail in the following examples and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Attached Figure 1 A schematic flow chart of a method for preparing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0028] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the specific implementation method, steps, structure, characteristics and effects of the method for preparing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene proposed by the present invention are described in detail below in combination with the accompanying drawings and preferred embodiments.

[0029] See also Figure 1 As shown, the method for preparing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene in a preferred embodiment of the present invention mainly comprises the following steps:

[0030] In one aspect, the present invention provides a method for synthesizing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene, comprising:

[0031] S1, performing a cracking reaction on a dicyclopentadiene raw material and a catalyst in a reactor to obtain a cracking product;

[0032] S2, removing water and propane from the cracking product to obtain cyclopentadiene;

[0033] S3, hydrogenating cyclopentadiene at a temperature of 140° C. to 150° C. and a pressure of 0.3 to 0.4 MPa in the presence of a catalyst, wherein the hydrogenation uses the cyclopentadiene obtained in step S2 as a solvent;

[0034] Wherein, the mass ratio of hydrogen to cyclopentadiene is 1.0 to 4.0.

[0035] The method provided by the embodiment of the present invention has at least the following beneficial effects:

[0036] By step S1, dicyclopentadiene raw material and catalyst are subjected to cracking reaction in a reactor to obtain cracking products; the cracking products include cyclopentadiene, water and propane, and the cracking products are treated with water and propane removal by step S2 to obtain cyclopentadiene; by step S3, cyclopentadiene is subjected to hydrogenation reaction, the hydrogenation reaction temperature is 140 ℃~150 ℃, the pressure is carried out at 0.3~0.4MPa, and the hydrogenation reaction is carried out in the presence of a catalyst, wherein the solvent used for hydrogenation is the cyclopentadiene obtained in step S2, and since the boiling point of cyclopentadiene itself is not high (41.5 ℃), it can be used as a solvent, and in the process of synthesizing cyclopentane by cracking cyclopentadiene from dicyclopentadiene, it is not considered to add other solvents, and the treatment of the newly added solvent in the subsequent steps is avoided, and the yield and purity of the product are improved. The method provided by the embodiment of the present invention has a short process route, does not require very high equipment requirements, and reduces the cost of equipment. Furthermore, the present invention does not need to introduce a solvent separately, and directly uses the cyclopentadiene produced in the preparation process as the solvent, does not produce by-products, and has a high conversion rate.

[0037] In an optional embodiment, the pyrolysis product is subjected to water removal and propane removal treatment in step S2, comprising: subjecting the pyrolysis product to distillation treatment through a depropanizing distillation tower;

[0038] The distillation conditions are as follows: the tower top pressure is 0.90MPa-0.95MPa, the tower bottom temperature is 125°C-128°C, and the reflux ratio is 1.0.

[0039] In the embodiment of the present invention, water and propane are removed from the cracking product by a distillation tower, and the cracking product is passed into the distillation tower, and cyclopentadiene is drawn out from the propane distillate of the distillation tower. Exemplarily, the distillation conditions may be: the tower top pressure may be 0.90MPa, 0.91MPa, 0.92MPa, 0.93MPa, 0.94MPa or 0.95MPa, the tower bottom temperature may be 125°C, 126°C, 127°C or 128°C, and the reflux ratio may be 1.0.

[0040] In an optional embodiment, the number of plates of the distillation tower is 5 to 18. For example, the number of plates of the distillation tower is 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17 or 18.

[0041] In an optional embodiment, in step S2, the propane removal temperature of the cracking product during the water and propane removal treatment is 43°C to 46°C, and the distillation temperature of the cyclopentadiene and cyclopentane mixture is 44°C to 46°C.

[0042] By controlling the distillation temperature of propane, the distillation temperature of cyclopentadiene and cyclopentane can be guaranteed, so that the temperature of cyclopentadiene is neither too high nor too low, which is beneficial to the hydrogenation reaction in the next step.

[0043] In an optional embodiment, the particle size of the catalyst is 20 mesh to 100 mesh. For example, the particle size of the catalyst can be 20 mesh, 21 mesh, 22 mesh, 23 mesh, 24 mesh, 25 mesh, 26 mesh, 27 mesh, 28 mesh, 29 mesh, 30 mesh, 40 mesh, 41 mesh, 52 mesh, 53 mesh, 64 mesh, 65 mesh, 76 mesh, 77 mesh, 88 mesh, 99 mesh or 100 mesh, etc.

[0044] In an optional embodiment, the hydrogenation time is 5 to 20 hours. For example, the hydrogenation time can be 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 16 hours, 17 hours, 19 hours or 20 hours, etc.

[0045] In an optional embodiment, the catalyst is selected from any one or more of Ni, Cu, Al, Pt, and Pd supported on alumina.

[0046] In an optional embodiment, the catalyst particle size is 20 mesh to 40 mesh.

[0047] On the other hand, a cyclopentane is provided, which is prepared by any of the above-mentioned methods for synthesizing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene.

[0048] The method for synthesizing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene provided by the present invention will be further explained and described below through optional embodiments.

[0049] Example 1

[0050] (1) Dicyclopentadiene (DCPD) was heated for 4 h -1 The water vapor is preheated to 450°C in the heating furnace at a speed of 2h, passes through the condenser, and enters the cracking furnace; (2) the water vapor is preheated to 450°C in the heating furnace at a speed of 2h -1The water vapor is preheated to 180°C by a heating furnace at a speed of 0.5 h and enters the third-stage cold box together with the DCPD preheated in (1); (3) the temperature of the water vapor is reduced to 55°C by countercurrent heat exchange in the cold box; (4) the cracking products are heated to 0.5 h -1 The speed of the reaction product is compressed to 0.35 MPa by a compressor, preheated to 130°C by a heating furnace, and then introduced into the reactor. The flow ratio of hydrogen to cracking product is 0.8 g / g; (5) The reaction product is heated to 0.44 h -1 The product comes out of the reactor at a speed and enters the three-stage cooler. The high-temperature water vapor and reaction heat in the product are used for preheating the water vapor in (2) through countercurrent heat exchange; (6) The product is subjected to a deweighting tower to remove heavy components. The pressure in the tower is controlled at 1.5 MPa, and cyclopentadiene is extracted from the bottom of the tower. (7) The cyclopentadiene enters the CP alkane reactor, and a precious metal catalyst is added to hydrogenate to prepare CP alkanes. The hydrogenation temperature is 60°C, the pressure is 0.4 MPa, and the reaction time is 2.5 hours. Hydrogen is introduced during the reaction, and the mass ratio of hydrogen to CPD is 1.2 g / g; (8) The reaction product is subjected to CP alkane refining, and non-condensable gas is removed to obtain a CP alkane product. The CP alkane content in the product is 95.6%, and the rest is tetrahydrodicyclopentadiene. This component can be directly used as a raw material for high-carbon alkanes without removal, and the CP alkane yield is 97.5%.

[0051] Example 2

[0052] (1) Dicyclopentadiene (DCPD) was heated for 4 h -1 The water vapor is preheated to 450°C in the heating furnace at a speed of 2h, passes through the condenser, and enters the cracking furnace; (2) the water vapor is preheated to 450°C in the heating furnace at a speed of 2h -1 The water vapor is preheated to 180°C by a heating furnace at a speed of 0.5 h and enters the third-stage cold box together with the DCPD preheated in (1); (3) the temperature of the water vapor is reduced to 55°C by countercurrent heat exchange in the cold box; (4) the cracking products are heated to 0.5 h -1 The speed of the reaction product is compressed to 0.35 MPa by a compressor, preheated to 130°C by a heating furnace, and then introduced into the reactor. The flow ratio of hydrogen to cracking product is 0.8 g / g; (5) The reaction product is heated to 0.44 h -1The product comes out of the reactor at a speed and enters the three-stage cooler. The high-temperature water vapor and reaction heat in the product are used for preheating the water vapor in (2) through countercurrent heat exchange; (6) The product is subjected to a deweighting tower to remove heavy components. The pressure in the tower is controlled at 1.5Mpa, and cyclopentadiene is extracted from the bottom of the tower. (7) The cyclopentadiene enters the CP alkane reactor, and a precious metal catalyst is added to hydrogenate to prepare CP alkanes. The hydrogenation temperature is 60°C, the pressure is 0.4MPa, and the reaction time is 3.5 hours. Hydrogen is introduced during the reaction, and the mass ratio of hydrogen to CPD is 1.1g / g; (8) The reaction product is subjected to CP alkane refining, and non-condensable gas is removed to obtain a CP alkane product. The CP alkane content in the product is 95.6%, and the rest is tetrahydrodicyclopentadiene. This component can be directly used as a raw material for high-carbon alkanes without removal, and the CP alkane yield is 97.6%.

[0053] Example 3

[0054] (1) Dicyclopentadiene (DCPD) was heated for 4 h -1 The water vapor is preheated to 450°C in the heating furnace at a speed of 2h, passes through the condenser, and enters the cracking furnace; (2) the water vapor is preheated to 450°C in the heating furnace at a speed of 2h -1 The water vapor is preheated to 180°C by a heating furnace at a speed of 0.5 h and enters the third-stage cold box together with the DCPD preheated in (1); (3) the temperature of the water vapor is reduced to 57°C by countercurrent heat exchange in the cold box; (4) the cracking products are heated to 0.5 h -1 The speed of the reaction product is compressed to 0.35 MPa by a compressor, preheated to 130°C by a heating furnace, and then introduced into the reactor. The flow ratio of hydrogen to cracking product is 0.8 g / g; (5) The reaction product is heated to 0.44 h -1 The product comes out of the reactor at a speed and enters the three-stage cooler. The high-temperature water vapor and reaction heat in the product are used for preheating the water vapor in (2) through countercurrent heat exchange; (6) The product is subjected to a deweighting tower to remove heavy components. The pressure in the tower is controlled at 1.5 MPa, and cyclopentadiene is extracted from the bottom of the tower. (7) The cyclopentadiene enters the CP alkane reactor, and a precious metal catalyst is added to hydrogenate to prepare CP alkanes. The hydrogenation temperature is 65°C, the pressure is 0.4 MPa, and the reaction time is 3.5 hours. Hydrogen is introduced during the reaction, and the mass ratio of hydrogen to CPD is 1.5 g / g; (8) The reaction product is subjected to CP alkane refining, and non-condensable gas is removed to obtain a CP alkane product. The CP alkane content in the product is 95.6%, and the rest is tetrahydrodicyclopentadiene. This component can be directly used as a raw material for high-carbon alkanes without removal, and the CP alkane yield is 98.6%.

[0055] Example 4

[0056] (1) Dicyclopentadiene (DCPD) was heated for 4 h -1 The water vapor is preheated to 460°C in the heating furnace at a speed of 2h, passes through the condenser, and enters the cracking furnace; (2) the water vapor is preheated to 460°C in the heating furnace at a speed of 2h-1 The water vapor is preheated to 180°C by a heating furnace at a speed of 0.5 h and enters the third-stage cold box together with the DCPD preheated in (1); (3) the temperature of the water vapor is reduced to 55°C by countercurrent heat exchange in the cold box; (4) the cracking products are heated to 0.5 h -1 The speed of the reaction product is compressed to 0.35 MPa by a compressor, preheated to 120°C by a heating furnace, and then introduced into the reactor. The flow rate ratio of hydrogen to cracking product is 1 g / g; (5) The reaction product is heated to 0.44 h -1 The product comes out of the reactor at a speed and enters the three-stage cooler. The high-temperature water vapor and reaction heat in the product are used for preheating the water vapor in (2) through countercurrent heat exchange; (6) The product is subjected to a deweighting tower to remove heavy components. The pressure in the tower is controlled at 1.5 MPa, and cyclopentadiene is extracted from the bottom of the tower. (7) The cyclopentadiene enters the CP alkane reactor, and a precious metal catalyst is added to hydrogenate to prepare CP alkanes. The hydrogenation temperature is 60°C, the pressure is 0.4 MPa, and the reaction time is 3.5 hours. Hydrogen is introduced during the reaction, and the mass ratio of hydrogen to CPD is 1.5 g / g; (8) The reaction product is subjected to CP alkane refining, and non-condensable gases are removed to obtain CP alkane products. The CP alkane content in the product is 96.6%, and the rest is tetrahydrodicyclopentadiene. This component can be directly used as a raw material for high-carbon alkanes without removal, and the CP alkane yield is 97.5%.

[0057] Example 5

[0058] (1) Dicyclopentadiene (DCPD) was heated for 4 h -1 The water vapor is preheated to 450°C in the heating furnace at a speed of 2h, passes through the condenser, and enters the cracking furnace; (2) the water vapor is preheated to 450°C in the heating furnace at a speed of 2h -1 The water vapor is preheated to 180°C by a heating furnace and enters the third-stage cold box together with the DCPD preheated in (1); (3) the temperature of the water vapor is reduced to 55°C by countercurrent heat exchange in the cold box; (4) the cracking products are heated to 0.6h -1 The speed of the reaction product is compressed to 0.45 MPa by a compressor, preheated to 140°C by a heating furnace, and then introduced into the reactor. Hydrogen is introduced, and the flow ratio of hydrogen to cracking product is 0.8 g / g; (5) The reaction product is heated at 0.44 h -1The product comes out of the reactor at a speed and enters the three-stage cooler. The high-temperature water vapor and reaction heat in the product are used for preheating the water vapor in (2) through countercurrent heat exchange; (6) The product is subjected to a deweighting tower to remove heavy components. The pressure in the tower is controlled at 1.5 MPa, and cyclopentadiene is extracted from the bottom of the tower. (7) The cyclopentadiene enters the CP alkane reactor, and a precious metal catalyst is added to hydrogenate to prepare CP alkanes. The hydrogenation temperature is 60°C, the pressure is 0.4 MPa, and the reaction time is 3.5 hours. Hydrogen is introduced during the reaction, and the mass ratio of hydrogen to CPD is 1.3 g / g; (8) The reaction product is subjected to CP alkane refining, and non-condensable gases are removed to obtain CP alkane products. The CP alkane content in the product is 95.9%, and the rest is tetrahydrodicyclopentadiene. This component can be directly used as a raw material for high-carbon alkanes without removal, and the CP alkane yield is 96.5%.

[0059] Example 6

[0060] (1) Dicyclopentadiene (DCPD) was heated for 4 h -1 The water vapor is preheated to 450°C in the heating furnace at a speed of 2h, passes through the condenser, and enters the cracking furnace; (2) the water vapor is preheated to 450°C in the heating furnace at a speed of 2h -1 The water vapor is preheated to 180°C by a heating furnace at a speed of 0.5 h and enters the third-stage cold box together with the DCPD preheated in (1); (3) the temperature of the water vapor is reduced to 57°C by countercurrent heat exchange in the cold box; (4) the cracking products are heated to 0.5 h -1 The speed of the reaction product is compressed to 0.35 MPa by a compressor, preheated to 130°C by a heating furnace, and then introduced into the reactor. The flow rate ratio of hydrogen to cracking product is 1.1 g / g. (5) The reaction product is heated to 0.44 h -1 The product comes out of the reactor at a speed and enters the three-stage cooler. The high-temperature water vapor and reaction heat in the product are used for preheating the water vapor in (2) through countercurrent heat exchange; (6) The product is subjected to a deweighting tower to remove heavy components. The pressure in the tower is controlled at 1.5Mpa, and cyclopentadiene is extracted from the bottom of the tower. (7) The cyclopentadiene enters the CP alkane reactor, and a precious metal catalyst is added to hydrogenate to prepare CP alkanes. The hydrogenation temperature is 60°C, the pressure is 0.4MPa, and the reaction time is 2.5 hours. Hydrogen is introduced during the reaction, and the mass ratio of hydrogen to CPD is 1.2g / g; (8) The reaction product is subjected to CP alkane refining, and non-condensable gases are removed to obtain CP alkane products. The CP alkane content in the product is 94.6%, and the rest is tetrahydrodicyclopentadiene. This component can be directly used as a raw material for high-carbon alkanes without removal, and the CP alkane yield is 95.6%.

[0061] Comparative Example 1

[0062] DCPD is loaded into a preheating furnace and heated to 450°C; water vapor enters the preheating furnace and mixes with DCPD. The DCPD-water vapor mixture is heated for 4 hours. -1The cracking temperature of the cracking bed is 500℃; the cracking products enter the compressor and then -1 The cracking product gas passed to the outlet of the cold box compressor at a speed of 10000 g / cm2 is cooled by the cold box and then enters the de-weighting tower; the product CPD is produced at the bottom of the de-weighting tower, and the non-condensable gas is produced at the top of the tower. The CPD content at the bottom of the de-weighting tower is 60%.

[0063] Comparative Example 2

[0064] The DCPD is heated to 550°C through a heating furnace at a rate of 300kg / h, passed through a condenser, and entered a cracking furnace; the water vapor is preheated to 200°C through a heating furnace at a rate of 150kg / h, and enters a two-stage cooler together with the preheated DCPD; the temperature of the water vapor is reduced to 25°C by countercurrent heat exchange in the cooler. The cracking product is compressed to a pressure of 6.5 kg through a compressor at a rate of 30kg / h, preheated to 240°C through a heating furnace, and enters a reactor, and hydrogen is introduced, with a flow ratio of hydrogen to cracking product of 0.8g / g; the reaction product is heated to 1h -1 The speed comes out of the reactor and enters the two-stage cooler. The high-temperature water vapor and reaction heat in the product are used for preheating the water vapor through countercurrent heat exchange; the reaction product passes through the deweighting tower to remove heavy dicyclopentadiene, the pressure in the tower is controlled at 50kpa, and isoprene is produced from the top of the tower. The dicyclopentadiene after distillation is distilled to remove the n-pentane therein, the pressure in the tower is controlled at 80kpa, and CPD with a mass fraction of 75% is produced at the bottom of the tower. CPD and hydrogen are introduced into the hydrogenation reactor in a volume ratio of 1:4 for hydrogenation reaction. The catalyst is a precious metal catalyst, the reaction temperature is 60°C, the pressure is 2.4mpa, the reaction time is 2 hours, and hydrogen is introduced during the reaction. The reaction product is subjected to CP alkane refining, non-condensable gas is removed, and CP alkane products are obtained. The CP alkane content in the product is 75.4%, and the rest is tetrahydrodicyclopentadiene. The CP alkane yield is 92.8%. This part of tetrahydrodicyclopentadiene can be used to produce alkylate oil with aromatics, and the product value is relatively low.

[0065] By comparing Examples 1 to 4 with Comparative Examples 1 and 2, it can be clearly seen that the yield of cyclopentane obtained by the method provided by the embodiment of the present invention is significantly higher than the yield of the product obtained by the method of Comparative Examples 1 to 2. In addition, the method used in Examples 1 to 4 uses simple equipment and has low equipment cost.

[0066] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modifications to equivalent embodiments of equivalent changes by using the methods and technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A method for synthesizing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene, characterized in that: include: S1, performing a cracking reaction on a dicyclopentadiene raw material and a catalyst in a reactor to obtain a cracking product; S2, removing water and propane from the cracking product to obtain cyclopentadiene; S3, hydrogenating the cyclopentadiene at a temperature of 140° C. to 150° C. and a pressure of 0.3 to 0.4 MPa in the presence of a catalyst; Wherein, the mass ratio of hydrogen to cyclopentadiene is 1.0 to 4.

0.

2. The method for synthesizing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene according to claim 1, characterized in that: In step S2, the pyrolysis product is subjected to water removal and propane removal treatment, including: the pyrolysis product is subjected to distillation treatment through a depropanizing distillation tower; The distillation conditions are as follows: the tower top pressure is 0.90MPa-0.95MPa, the tower bottom temperature is 125°C-128°C, and the reflux ratio is 1.

0.

3. The method for synthesizing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene according to claim 2, characterized in that: The number of plates of the distillation tower is 5 to 18.

4. The method for synthesizing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene according to claim 1, characterized in that: In step S2, the pyrolysis product is treated for dehydration and propane removal, and the distillation temperature for propane removal is 43°C to 46°C, and the distillation temperature for the cyclopentadiene and cyclopentane mixture is 44°C to 46°C.

5. The method for synthesizing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene according to claim 1, characterized in that: The particle size of the catalyst is 20 meshes to 100 meshes.

6. The method for synthesizing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene according to claim 1, characterized in that: The hydrogenation time is 5 to 20 hours.

7. The method for synthesizing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene according to claim 1, characterized in that: The catalyst is selected from any one or more of Ni, Cu, Al, Pt and Pd supported on alumina.

8. The method for synthesizing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene according to claim 1, characterized in that: The catalyst particle size is 20-40 meshes.

9. Cyclopentane, characterized in that The cyclopentane is prepared by the method for synthesizing cyclopentane by cracking dicyclopentadiene and hydrogenating cyclopentadiene as described in any one of claims 1 to 8.

Images