System for improving recycling rate of hydrogenation catalyst

Abstract

The utility model belongs to the technical field of sugar alcohol catalyst utilization, and relates to a system for improving the recycling rate of a hydrogenation catalyst, which comprises a raw material metering tank, a hydrogenation reaction kettle, a hot water tank, a settling tank, a washing liquid tank, a dilute alkali tank, a filtering tank, a product tank, a catalyst regeneration tank and a catalyst metering tank, the settling tank is used for settling the cooled sugar alcohol hydrogenation liquid containing the hydrogenation catalyst so as to separate precipitates and supernate, the filtering tank is used for filtering the supernate so as to obtain the sugar alcohol hydrogenation liquid and filtrate, and the product tank is used for storing the filtered sugar alcohol hydrogenation liquid. And the catalyst regeneration tank is used for recovering the hydrogenation catalyst in the settling tank and the filtrate in the filtering tank, and regenerating the recovered hydrogenation catalyst. The catalyst metering tank is used for storing the regenerated hydrogenation catalyst and preparing a hydrogenation catalyst solution. According to the utility model, high-efficiency recovery and regeneration of the hydrogenation catalyst in the maltose hydrogenation process are realized, and the recovery rate of the hydrogenation catalyst is improved.

Description

Technical Field

[0001] This invention belongs to the field of sugar alcohol catalyst utilization technology, and specifically relates to a system for improving the recovery and utilization rate of hydrogenation catalysts. Background Technology

[0002] Existing Raney nickel catalysts are solid heterogeneous catalysts with porous structures, formed by etching aluminum-nickel alloys with sodium hydroxide. This porous structure provides a large specific surface area and abundant active sites, making it easier for reactant molecules to be adsorbed, thus increasing reaction opportunities. Furthermore, the main component of Raney nickel catalysts is nickel metal, which has the ability to transfer electrons and activate reactant molecules. Therefore, Raney nickel catalysts can adsorb a large number of hydrogen molecules and dissociate them into active hydrogen atoms, which then undergo addition reactions with unsaturated compounds. They are widely used in the hydrogenation of sugar alcohols. However, Raney nickel catalysts are extremely small in size and easily lost during the hydrogenation of sugar compounds. They are also affected by the raw materials and byproducts of the hydrogenation process, such as soluble proteins, sugar decomposition products, and gluconic acid, which can easily damage or clog the active sites, resulting in a significant loss of Raney nickel catalyst activity.

[0003] Currently, to control the loss of Raney nickel catalyst during the hydrogenation of carbohydrates, a method of multiple settling cycles lasting 3-8 hours is commonly used to recover part of the catalyst. However, this method is time-consuming and prone to agglomeration and pipeline blockage. Repeated washing with purified water after recovery fails to effectively remove contaminants and restore activity. Furthermore, washing with 5% sodium hydride easily leads to nickel ion loss, polluting the environment and increasing remediation costs. Therefore, a more effective method for restoring the activity of Raney nickel catalyst is needed. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a system for improving the recovery and utilization rate of hydrogenation catalysts, realizing the efficient recovery and regeneration of hydrogenation catalysts during the hydrogenation process of maltose, improving the recovery and utilization rate of hydrogenation catalysts, and improving the activity recovery effect of hydrogenation catalysts.

[0005] This invention is implemented as follows: a system for improving the recovery and utilization rate of hydrogenation catalysts is provided, including a raw material metering tank, a hydrogenation reactor, a settling tank, and a catalyst metering tank. A raw material pipeline is provided at the discharge end of the raw material metering tank and connected to the feed end of the hydrogenation reactor. A discharge pipeline is provided at the discharge end of the hydrogenation reactor and connected to the feed end of the settling tank. A catalyst pipeline is provided at the discharge end of the catalyst metering tank and connected to the feed end of the hydrogenation reactor. The system also includes a hot water tank, a washing liquid tank, a dilute alkali tank, a filter tank, a product tank, and a catalyst regeneration tank. A cooling coil is provided in the hot water tank, with its two ends connected in series with the discharge pipeline. A hot water pipeline is provided at the water outlet end of the hot water tank and connected to the feed end of the washing liquid tank. A washing liquid pipeline is provided at the discharge end of the washing liquid tank and connected to the feed end of the catalyst regeneration tank. The settling tank is equipped with a discharge end for facilitating the discharge of sediment located at the bottom of the tank and a liquid discharge end for facilitating the discharge of supernatant located at the top of the tank. A first recovery pipe is connected to the inlet end of the catalyst regeneration tank at the discharge end of the settling tank, and a liquid discharge pipe is connected to the inlet end of the filter tank at the liquid discharge end of the settling tank. A second recovery pipe is connected to the inlet end of the catalyst regeneration tank at the discharge end of the filter tank. A filter screen is installed in the filter tank, and a sugar solution pipe is connected to the inlet end of the product tank at the discharge end of the filter screen. A third recovery pipe is connected to the inlet end of the catalyst metering tank at the discharge end of the catalyst regeneration tank. A regeneration stirring device is installed inside the catalyst regeneration tank. A first alkali solution pipe is connected to the inlet end of the washing liquid tank at the discharge end of the dilute alkali tank.

[0006] Furthermore, a second alkali pipe and a third alkali pipe are respectively provided at the discharge end of the dilute alkali tank. The second alkali pipe is connected to the feed end of the raw material metering tank, and the third alkali pipe is connected to the feed end of the hydrogenation reactor.

[0007] Furthermore, a first alkali injection pump is installed on the first alkali pipeline, a second alkali injection pump is installed on the second alkali pipeline, and a third alkali injection pump is installed on the third alkali pipeline.

[0008] Furthermore, an inlet pipe for the sugar alcohol solution to be hydrogenated is provided on the raw material metering tank, a hydrogen pipeline for easy addition of hydrogen is provided at the feed end of the hydrogenation reactor, and a catalyst feed pipe for easy addition of hydrogenation catalyst is provided on the catalyst metering tank.

[0009] Furthermore, a first recycling pump is installed on the first recycling pipeline, and a second recycling pump is installed on the second recycling pipeline.

[0010] Furthermore, a drainage pump is installed on the drainage pipe, a discharge pump is installed on the raw material pipe, a washing liquid pump is installed on the washing liquid pipe, and a catalyst pump is installed on the catalyst pipe.

[0011] Furthermore, a reactor stirring device is installed in the hydrogenation reactor, a washing liquid stirring device is installed in the washing liquid tank, and a metering stirrer is installed in the catalyst metering tank.

[0012] Furthermore, a nitrogen pipeline is provided at the feed end of the filter screen of the filter tank.

[0013] Furthermore, a hot water valve is installed on the hot water pipe, a first purified water pipe is installed at the inlet end of the hot water tank, and a second purified water pipe is installed at the inlet end of the washing liquid tank.

[0014] Compared with existing technologies, the system for improving the recovery rate of hydrogenation catalysts of this invention has the following characteristics:

[0015] 1. Shortens the production time of the hydrogenation reaction and reduces the agglomeration caused by the long-term sedimentation of the catalyst;

[0016] 2. Improve catalyst recovery efficiency by using a self-draining filtration device;

[0017] 3. Use a suitable hot alkaline cleaning solution to clean the hydrogenation catalyst, effectively restoring its activity and improving its utilization efficiency.

[0018] 4. Enhance the recovery and utilization of reaction heat. Attached Figure Description

[0019] Figure 1 This is a schematic diagram illustrating the principle of the system for improving the recovery and utilization rate of hydrogenation catalysts according to this invention.

[0020] In the diagram, the following are the labels: 1. Raw material metering tank; 2. Hydrogenation reactor; 3. Hot water tank; 4. Settling tank; 5. Washing liquid tank; 6. Dilute alkali tank; 7. Filter tank; 8. Product tank; 9. Catalyst regeneration tank; 10. Catalyst metering tank; 11. Raw material pipeline; 12. Discharge pipeline; 13. Cooling coil; 14. Hot water pipeline; 15. Washing liquid pipeline; 16. First recovery pipeline; 17. Drainage pipeline; 18. Second recovery pipeline; 19. Sugar solution pipeline; 20. Third recovery pipeline; 21. Regeneration stirring device; 22. First alkali solution pipeline; 23. Second alkali solution pipeline. Pipelines; 24. Third alkali solution pipeline; 25. Catalyst pipeline; 26. Discharge pump; 27. Catalyst pump; 28. Drain pump; 29. ​​First recovery pump; 30. Second recovery pump; 31. First alkali injection pump; 32. Washing solution pump; 33. Third alkali injection pump; 34. Second alkali injection pump; 35. Filter screen; 36. Nitrogen pipeline; 37. Hot water valve; 38. First purified water pipeline; 39. Second purified water pipeline; 40. Liquid inlet pipeline; 41. Hydrogen pipeline; 42. Catalyst feed pipeline; 43. Reactor stirring device; 44. Washing solution stirring device; 45. Metering stirrer. Detailed Implementation

[0021] To make the technical problems, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0022] Please refer to Figure 1 As shown in the figure, this is a preferred embodiment of the system for improving the recovery and utilization rate of hydrogenation catalysts according to the present invention. The arrows in the figure indicate the flow direction of various materials in the system. The system includes a raw material metering tank 1, a hydrogenation reactor 2, a hot water tank 3, a settling tank 4, a washing liquid tank 5, a dilute alkali tank 6, a filter tank 7, a product tank 8, a catalyst regeneration tank 9, and a catalyst metering tank 10.

[0023] The raw material metering tank 1 is used to store the sugar alcohol solution to be hydrogenated. The hydrogenation reactor 2 is used to hydrogenate the sugar alcohol solution to obtain a sugar alcohol hydrogenated liquid containing a hydrogenation catalyst. The hot water tank 3 is used to cool the sugar alcohol hydrogenated liquid containing the hydrogenation catalyst flowing through it. The settling tank 4 is used to settle the cooled sugar alcohol hydrogenated liquid containing the hydrogenation catalyst to separate the precipitate and supernatant. The precipitate mainly contains the hydrogenation catalyst, and the supernatant is mainly a mixed solution of the sugar alcohol hydrogenated liquid and the hydrogenation catalyst. The washing tank 5 is used to prepare an alkaline washing solution for regenerating and cleaning the hydrogenation catalyst. The dilute alkali tank 6 is used to adjust the pH value of the alkaline washing solution. The filter tank 7 is used to filter the supernatant to obtain the sugar alcohol hydrogenated liquid and the filtrate containing the hydrogenation catalyst. The product tank 8 is used to store the filtered sugar alcohol hydrogenated liquid. The catalyst regeneration tank 9 is used to recover the hydrogenation catalyst from the settling tank 4 and the filtrate containing the hydrogenation catalyst from the filter tank 7, and to regenerate the recovered hydrogenation catalyst. The catalyst metering tank 10 is used to store the regenerated hydrogenation catalyst and to prepare the hydrogenation catalyst solution.

[0024] A raw material pipeline 11 is provided at the discharge end of the raw material metering tank 1 and connected to the feed end of the hydrogenation reactor 2. A discharge pipeline 12 is provided at the discharge end of the hydrogenation reactor 2 and connected to the feed end of the settling tank 4. A catalyst pipeline 25 is provided at the discharge end of the catalyst metering tank 10 and connected to the feed end of the hydrogenation reactor 2.

[0025] A cooling coil 13 is installed inside the hot water tank 3, with its two ends connected in series with the discharge pipe 12. A hot water pipe 14 is installed at the outlet of the hot water tank 3 and connected to the inlet of the washing liquid tank 5. A washing liquid pipe 15 is installed at the outlet of the washing liquid tank 5 and connected to the inlet of the catalyst regeneration tank 9.

[0026] The settling tank 4 is provided with a discharge end for facilitating the discharge of sediment located in the lower part of the tank and a liquid discharge end for facilitating the discharge of supernatant located in the upper part of the tank. A first recovery pipe 16 is provided at the discharge end of the settling tank 4 and is connected to the feed end of the catalyst regeneration tank 9. A drain pipe 17 is provided at the liquid discharge end of the settling tank 4 and is connected to the feed end of the filter tank 7.

[0027] A second recovery pipe 18 is provided at the discharge end of the filter tank 7, connecting to the inlet end of the catalyst regeneration tank 9. A filter screen 35 is provided in the filter tank 7, and a sugar solution pipe 19 is provided at the discharge end of the filter screen 35, connecting to the inlet end of the product tank 8. A third recovery pipe 20 is provided at the discharge end of the catalyst regeneration tank 9, connecting to the inlet end of the catalyst metering tank 10. A regeneration stirring device 21 is provided inside the catalyst regeneration tank 9.

[0028] A first alkali pipe 22 is provided at the discharge end of the dilute alkali tank 6 and is connected to the inlet end of the washing liquid tank 5. A second alkali pipe 23 and a third alkali pipe 24 are also provided at the discharge end of the dilute alkali tank 6. The second alkali pipe 23 is connected to the inlet end of the raw material metering tank 1, and the third alkali pipe 24 is connected to the inlet end of the hydrogenation reactor 2.

[0029] A first alkali injection pump 31 is installed on the first alkali pipeline 22, a second alkali injection pump 34 is installed on the second alkali pipeline 23, and a third alkali injection pump 33 is installed on the third alkali pipeline 24. A first recovery pump 29 is installed on the first recovery pipeline 16, and a second recovery pump 30 is installed on the second recovery pipeline 18. A discharge pump 28 is installed on the discharge pipeline 17, and a discharge pump 26 is installed on the raw material pipeline 11. A catalyst pump 27 is installed on the catalyst pipeline 25, and a washing pump 32 is installed on the washing liquid pipeline 15. The catalyst pump 27, discharge pump 28, first recovery pump 29, and second recovery pump 30 are all diaphragm pumps.

[0030] A nitrogen pipeline 36 is provided at the feed end of the filter screen in the filter tank 7. The hydrogenation catalyst trapped by the filter screen 35 after filtration is backflushed and stripped by nitrogen through the nitrogen pipeline 36.

[0031] A hot water valve 37 is installed on the hot water pipe 14, a first purified water pipe 38 is installed at the inlet end of the hot water tank 3, and a second purified water pipe 39 is installed at the inlet end of the washing liquid tank 5. Purified water enters the hot water tank 3 and the washing liquid tank 5 through the first purified water pipe 38 and the second purified water pipe 39, respectively.

[0032] A liquid inlet pipe 40 for the sugar alcohol solution to be hydrogenated is provided on the raw material metering tank 1, a hydrogen pipeline 41 for easy addition of hydrogen is provided at the feed end of the hydrogenation reactor 2, and a catalyst feed pipe 42 for easy addition of hydrogenation catalyst is provided on the catalyst metering tank 10.

[0033] A stirring device 43 is installed inside the hydrogenation reactor 2 to stir the reactants inside the reactor 2 evenly, thereby improving the efficiency of the hydrogenation reaction. A washing liquid stirring device 44 is installed inside the washing liquid tank 5, and a metering stirrer 45 is installed inside the catalyst metering tank 10.

[0034] Please refer to again Figure 1 As shown, this utility model also discloses a method for improving the recovery rate of hydrogenation catalysts, which uses the system for improving the recovery rate of hydrogenation catalysts as described above. The method includes the following steps:

[0035] Step 1: The sugar alcohol solution to be hydrogenated, stored in the raw material metering tank 1, is injected into the hydrogenation reactor 2 through the raw material pipe 11. The hydrogenation catalyst in the catalyst metering tank 10 is also injected into the hydrogenation reactor 2 through the catalyst pipe 25. The sugar alcohol solution undergoes hydrogenation in the hydrogenation reactor 2. After hydrogenation, the resulting sugar alcohol hydrogenated liquid containing the hydrogenation catalyst flows through the hot water tank 3 for cooling and then enters the settling tank 4 for short-term settling of 1–1.5 hours. The supernatant and precipitate are obtained after settling. The filter screen 35 is a filter cloth with a pore size of 10 μm.

[0036] Step 2: The supernatant enters the filter tank 7 through the drain pipe 17 for filtration. The filtered sugar alcohol hydrogenated liquid enters the product tank 8 through the sugar solution pipe 19 for temporary storage. The filtrate containing the hydrogenation catalyst enters the catalyst regeneration tank 9 through the second recovery pipe 18 for temporary storage. The precipitate enters the catalyst regeneration tank 9 through the first recovery pipe 16 for temporary storage.

[0037] Step 3: Inject the dilute alkali from the dilute alkali tank 6 into the washing solution tank 5 through the first alkali solution pipeline 22. Adjust the pH of the washing solution in the washing solution tank 5 to 8.5–9.5 and the temperature to 75–85℃. Then, discharge the washing solution into the catalyst regeneration tank 9 through the washing solution pipeline 15. The washing solution stirs and regenerates the recovered hydrogenation catalyst. Control the stirring speed of the regeneration stirring device 21 to 100 rpm and the stirring time to >30 min.

[0038] Step 4: The regenerated hydrogenation catalyst is discharged into the catalyst metering tank 10 through the third recovery pipeline 20 for reuse.

[0039] The following specific embodiments and comparative examples further illustrate the system for improving the recovery and utilization rate of hydrogenation catalysts according to this invention.

[0040] Example 1

[0041] In the first embodiment of this invention, the method for improving the recovery rate of hydrogenation catalysts uses maltose syrup as the sugar alcohol solution to be hydrogenated and Raney nickel as the hydrogenation catalyst. This embodiment includes the following steps:

[0042] Step 11, at 10m3 Hydrogenation reactor 2 internal injection 6m 3 Malt syrup with a catalyst concentration of 5-10% is hydrogenated and heated to 130-140°C for 3 hours. After the hydrogenation reaction is completed, the reaction liquid flows through a hot water tank 3 to cool down.

[0043] Step 12: After cooling, the reaction solution settles in settling tank 4 for 1-1.5 hours. Using drainage pump 28, the supernatant from settling tank 4 is transferred to filter tank 7 at a flow rate of 6 m³ / s. 3 / h. The maltitol solution obtained from filtration enters the finished product tank 8 through the sugar solution pipeline 19 for temporary storage. After filtration, nitrogen is used to backflush the filter screen 35 through the nitrogen pipeline 36 to remove the attached hydrogenation catalyst. The hydrogenation catalyst falls to the bottom of the filter tank 7 and is recovered into the catalyst regeneration tank 10.

[0044] Comparative Example 1

[0045] The comparative example uses the same raw materials and catalyst as Example 1. The comparative example includes steps D11 and D12. Step D11 is the same as step 11 of Example 1. Step D12: After the cooled reaction liquid settles for 3 hours in the primary settling tank 4, the supernatant after sedimentation is transported to another settling tank for secondary settling using a diaphragm pump. After the second settling for 8 to 10 hours, the obtained supernatant is transported to the finished product tank 8. The hydrogenation catalyst obtained from the primary and secondary settling is recovered into the catalyst regeneration tank 10.

[0046] The recovery efficiency of Example 1 and Comparative Example 1 was compared, and the data are shown in Table 1.

[0047] Table 1 Comparison of recovery efficiency between Example 1 and Comparative Example 1

[0048] recycling cycle Raney nickel recovery rate Product filtration speed Example 1 2 to 2.5 hours 96.1％ 71 mL / min Comparative Example 1 11 to 13 hours 94.3％ 67 mL / min

[0049] As can be seen from Table 1, Example 1 takes less time to recover the catalyst, has a higher recovery rate, and produces better quality products. There is no phenomenon of high filtration rate caused by excessive catalyst residue in the product.

[0050] Example 2

[0051] In the second embodiment of the method for improving the recovery rate of hydrogenation catalysts according to this invention, the sugar alcohol solution to be hydrogenated is maltose syrup, and the hydrogenation catalyst is Raney nickel. This embodiment includes the following steps:

[0052] Step 21 is the same as step 11 in Example 1.

[0053] Step 22 is the same as step 12 in Example 1.

[0054] Step 23: After the purified water in hot water tank 3 absorbs part of the reaction heat and reaches a temperature of 85-95℃, the hot water is discharged into cleaning tank 5. Cold purified water is added according to the temperature monitoring of cleaning tank 5, and the temperature is adjusted to 50℃, 60℃, 70℃, 80℃, and 90℃ respectively. Cleaning solution is added to catalyst regeneration tank 9 at a volume equal to that in catalyst regeneration tank 9. Cleaning solution is added as needed according to the temperature monitoring of catalyst regeneration tank 9 to ensure the temperature of catalyst regeneration tank 9 is 45℃, 55℃, 65℃, 75℃, and 85℃. The stirring speed of regeneration stirring device 21 is 100 rpm, the stirring time is 30 min, and the settling time is 60 min. Samples are taken to test the hydrogen absorption activity of the regenerated hydrogenation catalyst after cleaning, and the data are shown in Table 2 below.

[0055] Table 2 Comparison of the cleaning effects of purified water at different temperatures on regenerated hydrogenation catalysts

[0056] Cleaning temperature (°C) 45 55 65 75 85 Hydrogen absorption activity (mL / g·min) 1.23 1.20 1.34 1.51 1.57

[0057] Table 2 shows that the activity of the regenerated hydrogenation catalyst increases with increasing water washing temperature, with 75–85°C being the optimal washing temperature. Furthermore, while the catalyst activity increases, it does not significantly indicate that washing with hot purified water alone is ineffective in recovering the hydrogenation catalyst. Therefore, the washing solution was optimized according to Example 3.

[0058] Example 3

[0059] The third embodiment of this invention's method for improving the recovery rate of hydrogenation catalysts uses maltose syrup as the sugar alcohol solution to be hydrogenated and Raney nickel as the hydrogenation catalyst. This embodiment includes the following steps:

[0060] Step 31 is the same as step 11 in Example 1.

[0061] Step 32 is the same as step 12 in Example 1.

[0062] Step 33: After absorbing part of the reaction heat, the purified water in hot water tank 3 reaches a temperature of 85-95℃. The hot water is then discharged into cleaning tank 5. Cold purified water is added according to the thermometer in cleaning tank 5, and the temperature is adjusted to 75-85℃. Alkaline substances, sodium carbonate or sodium hydroxide, are injected into the cleaning solution according to the pH meter in cleaning tank 5, adjusting the pH value to 8±0.5, 9±0.5, 10±0.5, 11±0.5, and 12±0.5 respectively. The cleaning solution is added to catalyst regeneration tank 9 at a volume equal to that in the catalyst regeneration tank 9. The temperature in catalyst regeneration tank 9 is monitored and adjusted as needed to maintain a temperature of 75-85℃. The regeneration stirring device 21 operates at 100 rpm for 30 minutes, followed by 60 minutes of settling. Samples are taken to test the hydrogen absorption activity and aluminum content of the regenerated hydrogenation catalyst after cleaning.

[0063] Table 3 Comparison of cleaning effects of different pH cleaning solutions on regenerated hydrogenation catalysts

[0064]

[0065] Table 3 shows that cleaning with a higher pH value in the 75–85℃ range can better restore the activity of the regenerated catalyst, but sodium hydroxide causes more severe corrosion to the regenerated hydrogenation catalyst. Furthermore, as the pH increases, aluminum loss from the hydrogenation catalyst becomes more significant. In summary, using sodium carbonate to adjust the pH of the cleaning solution to 9±0.5 is the optimal choice. Under these conditions, the hydrogenation catalyst effectively removes impurities such as proteins and sugars after cleaning, recovers a greater degree of activity, and aluminum loss remains within a controllable range.

[0066] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A system for improving the recovery rate of hydrogenation catalysts, comprising a feed metering tank, a hydrogenation reactor, a settling tank, and a catalyst metering tank, wherein a feed pipeline is provided at the outlet end of the feed metering tank and connected to the inlet end of the hydrogenation reactor, a discharge pipeline is provided at the outlet end of the hydrogenation reactor and connected to the inlet end of the settling tank, and a catalyst pipeline is provided at the outlet end of the catalyst metering tank and connected to the inlet end of the hydrogenation reactor, characterized in that, The system also includes a hot water tank, a washing liquid tank, a dilute alkali tank, a filter tank, a product tank, and a catalyst regeneration tank. A cooling coil is installed inside the hot water tank, with both ends connected in series with a discharge pipe. A hot water pipe is connected to the inlet of the washing liquid tank at the outlet of the hot water tank, and a washing liquid pipe is connected to the inlet of the catalyst regeneration tank at the outlet of the washing liquid tank. The settling tank is equipped with an outlet for facilitating the discharge of sediment located at the bottom of the tank and an outlet for facilitating the discharge of supernatant located at the top of the tank. A first recovery pipe is installed at the outlet of the settling tank. The feed inlet of the catalyst regeneration tank is connected to the outlet of the settling tank. A drain pipe is installed at the outlet of the settling tank and connected to the feed inlet of the filter tank. A second recovery pipe is installed at the outlet of the filter tank and connected to the feed inlet of the catalyst regeneration tank. A filter screen is installed in the filter tank. A sugar solution pipe is installed at the outlet of the filter screen and connected to the feed inlet of the product tank. A third recovery pipe is installed at the outlet of the catalyst regeneration tank and connected to the feed inlet of the catalyst metering tank. A regeneration stirring device is installed inside the catalyst regeneration tank. A first alkali solution pipe is installed at the outlet of the dilute alkali tank and connected to the feed inlet of the washing liquid tank.

2. The system for improving the recovery rate of hydrogenation catalysts as described in claim 1, characterized in that, A second alkali pipe and a third alkali pipe are respectively installed at the discharge end of the dilute alkali tank. The second alkali pipe is connected to the feed end of the raw material metering tank, and the third alkali pipe is connected to the feed end of the hydrogenation reactor.

3. The system for improving the recovery rate of hydrogenation catalysts as described in claim 2, characterized in that, A first alkali injection pump is installed on the first alkali pipeline, a second alkali injection pump is installed on the second alkali pipeline, and a third alkali injection pump is installed on the third alkali pipeline.

4. The system for improving the recovery rate of hydrogenation catalysts as described in claim 1, characterized in that, An inlet pipe for the sugar alcohol solution to be hydrogenated is provided on the raw material metering tank, a hydrogen pipeline for easy addition of hydrogen is provided at the feed end of the hydrogenation reactor, and a catalyst feed pipe for the hydrogenation catalyst is provided on the catalyst metering tank.

5. The system for improving the recovery rate of hydrogenation catalysts as described in claim 1, characterized in that, A first recycling pump is installed on the first recycling pipeline, and a second recycling pump is installed on the second recycling pipeline.

6. The system for improving the recovery rate of hydrogenation catalysts as described in claim 1, characterized in that, A drainage pump is installed on the drainage pipeline, a discharge pump is installed on the raw material pipeline, a washing liquid pump is installed on the washing liquid pipeline, and a catalyst pump is installed on the catalyst pipeline.

7. The system for improving the recovery rate of hydrogenation catalysts as described in claim 1, characterized in that, A reactor stirring device is installed in the hydrogenation reactor, a washing liquid stirring device is installed in the washing liquid tank, and a metering stirrer is installed in the catalyst metering tank.

8. The system for improving the recovery rate of hydrogenation catalysts as described in claim 1, characterized in that, A nitrogen pipeline is installed at the feed end of the filter screen of the filter tank.

9. The system for improving the recovery rate of hydrogenation catalyst as described in claim 1, characterized in that, A hot water valve is installed on the hot water pipe, a first purified water pipe is installed at the inlet end of the hot water tank, and a second purified water pipe is installed at the inlet end of the washing liquid tank.

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