Electrochemical catalysis polysaccharide oxidation device and process method

Abstract

The invention relates to the technical field of electrochemical catalytic oxidation and polysaccharide oxidation processes, in particular to an electrochemical catalytic polysaccharide oxidation device and a process method. The device comprises an electrolytic tank, the electrolytic tank comprises an anode chamber, a cathode chamber and a bipolar membrane for separating the anode chamber and the cathode chamber, a filter membrane channel is arranged in the anode chamber, a polysaccharide solution is injected into the filter membrane channel, and a periodate solution is injected into the anode chamber; the periodate solution can penetrate through the filter membrane channel, the periodate solution and the polysaccharide solution are subjected to an electrochemical oxidation reaction, and iodide-containing ions generated by the electrochemical oxidation reaction can penetrate through the filter membrane channel and enter the anode chamber. According to the method, the reactant polysaccharide and the oxidation product dialdehyde polysaccharide thereof are limited in the filter membrane channel, so that the regeneration efficiency of periodate is improved, and the separation and purification efficiency of dialdehyde polysaccharide and iodide-containing ions is improved; the problems of low periodate regeneration efficiency and low dialdehyde polysaccharide purification efficiency in the circulating process of repeatedly oxidizing polysaccharide on an electrode at present are solved.

Description

Technical Field

[0001] The invention relates to the technical field of electrochemical catalytic oxidation and polysaccharide oxidation process, and in particular to an electrochemical catalytic polysaccharide oxidation device and process method. Background Art

[0002] Polysaccharides with adjacent diol structural units can selectively introduce aldehyde groups at the corresponding positions after the ring-opening oxidation of their dihydroxyl groups to obtain dialdehyde polysaccharides. Dialdehyde polysaccharides can undergo reductive amination reactions with materials containing amino groups, which is a widely used strategy for constructing Schiff bases. In addition, dialdehyde polysaccharides can react with materials containing carbonyl / hydroxyl groups through aldol reactions. Therefore, oxidized polysaccharides have rich industrial application prospects and the potential to be used as versatile and sustainable modular molecules to manufacture advanced functional materials.

[0003] The traditional preparation process of dialdehyde polysaccharides is mainly to react a polysaccharide dissolved in a solvent with periodate, and then separate the generated oxide dialdehyde polysaccharide from the residual solvent, periodate ions, iodate ions and iodide ions. Among them, sodium periodate is the main component for preparing dialdehyde polysaccharides. However, industrial sodium periodate is produced by electrochemical oxidation of sodium iodate, which makes the cost of sodium periodate high, and ultimately leads to high raw material costs for preparing dialdehyde polysaccharides. In addition, the various iodine-containing ions generated after the periodate is reduced need to be separated from the dialdehyde polysaccharide to avoid contaminating the dialdehyde polysaccharide; and the various iodine-containing ions generated are extremely harmful to the environment and cannot be directly discharged, but require specific chemical / physical processes to remove the iodine-containing ions, which causes the traditional preparation process of dialdehyde polysaccharides to have complex post-processing procedures and relatively high costs.

[0004] At present, in order to recycle periodate, the reaction of periodate and polysaccharide can be limited to the anode chamber of the electrolytic cell, and the polysaccharide and periodate ion can be limited to the anode chamber by a cation exchange membrane. The iodate ions obtained after the periodate ions oxidize the polysaccharide are re-oxidized to periodate ions on the anode through an electrochemical reaction, so that the one-time oxidation of the polysaccharide by the traditional periodate can be converted into a cyclic process of repeatedly oxidizing the polysaccharide on the electrode. However, the current cyclic process of repeatedly oxidizing polysaccharides on the electrode is limited to the regeneration efficiency of periodate, which is mainly due to the current method of placing the polysaccharide solution and the periodate ion solution in the same space. Therefore, when the product polysaccharide / dialdehyde polysaccharide solution is removed from the anode chamber, the polysaccharide / dialdehyde polysaccharide is in a uniformly mixed state with a variety of iodide-containing ions, resulting in the loss of periodate ions as the product is transferred out of the electrolytic cell, reducing the regeneration efficiency of periodate ions. Moreover, the various iodide-containing ions mixed with the product solution further lead to the problem of low dialdehyde polysaccharide purification efficiency. Summary of the invention

[0005] In order to solve the problems of low regeneration efficiency of periodate and low purification efficiency of dialdehyde polysaccharides in the current cyclic process of repeated oxidation of polysaccharides on electrodes, the purpose of the present invention is to provide an electrochemical catalytic polysaccharide oxidation device and process method.

[0006] The process method of the invention can improve the efficiency of periodate-catalyzed polysaccharide oxidation to dialdehyde polysaccharide and the periodate regeneration efficiency, reduce the periodate cost, and improve the dialdehyde polysaccharide purification efficiency.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows.

[0008] The present invention provides an electrochemical catalytic polysaccharide oxidation device, comprising an electrolytic cell, wherein the electrolytic cell comprises an anode chamber and a cathode chamber and a bipolar membrane separating the anode chamber and the cathode chamber, wherein a filter membrane channel is arranged in the anode chamber, a polysaccharide solution is injected into the filter membrane channel, and a periodate solution is injected into the anode chamber; the filter membrane channel can allow the periodate solution to pass through and react with the polysaccharide solution through electrochemical oxidation, and can allow iodine-containing ions generated by the electrochemical oxidation reaction to pass through and enter the anode chamber.

[0009] The present invention limits the reactant polysaccharide and its oxidation product dialdehyde polysaccharide in the filter membrane channel, and can avoid moving all iodine-containing anions out of the anode chamber when extracting the product in the filter membrane channel, thereby improving the periodate regeneration efficiency and the separation and purification efficiency of the dialdehyde polysaccharide and the iodine-containing ions, and solves the problems of low periodate regeneration efficiency and low dialdehyde polysaccharide purification efficiency in the current cyclic process of repeatedly oxidizing polysaccharides on electrodes.

[0010] Preferably, the pore size of the filter membrane channel satisfies the following conditions:

[0011] The molecular weight cutoff of the filter membrane channel is between 500 and 100,000; the molecular weight cutoff of the filter membrane channel is smaller than the molecular weight of the polysaccharide in the polysaccharide solution; and the molecular weight cutoff of the filter membrane channel is smaller than the molecular weight of the dialdehyde polysaccharide produced by the electrochemical oxidation reaction.

[0012] Preferably, the molecular weight of the polysaccharide in the polysaccharide solution is 5000-10000000; the molecular weight of the dialdehyde polysaccharide produced by the electrochemical oxidation reaction is 4000-8000000.

[0013] Preferably, the pore size of the filter membrane of the filter membrane channel is 1 nm to 50 nm.

[0014] Preferably, the filter membrane material of the filter membrane channel is at least one of aluminum oxide membrane, zirconium dioxide membrane, silicon carbide membrane, silicon dioxide membrane, titanium dioxide membrane, cellulose acetate membrane, cellulose acetate ester membrane, cellulose triacetate membrane, polyethylene membrane, polypropylene membrane, polybutylene membrane, polyvinylidene fluoride membrane, polytetrafluoroethylene membrane, polysulfone membrane, polyethersulfone membrane, sulfonated polyethersulfone membrane, polyacrylonitrile resin membrane, polyimide membrane, polyamide membrane, and polyaryletherketone membrane.

[0015] Preferably, the periodate is at least one of metaperiodic acid, orthoperiodic acid, potassium metaperiodate, sodium metaperiodate, sodium orthoperiodate, potassium orthoperiodate, potassium diorthoperiodate, sodium diorthoperiodate, sodium paraperiodate, potassium paraperiodate, potassium dimetaperiodate, and sodium dimetaperiodate; the polysaccharide is a polysaccharide having a vicinal diol group, and the polysaccharide is at least one of alginic acid, alginate, hyaluronic acid, hyaluronate, starch, glycogen, dextran, pectin, agar, cellulose, or a derivative thereof.

[0016] Preferably, the concentration of the polysaccharide solution is 0.05 w / v% to 15 w / v%; the concentration of the periodate solution is 0.01M to 2M.

[0017] Preferably, the electrochemical catalytic polysaccharide oxidation device includes a first booster device and a second booster device, wherein the first booster device is connected to the filter membrane channel to adjust the pressure of the filter membrane channel; the second booster device is connected to the anode chamber to adjust the pressure of the anode chamber.

[0018] The present invention pressurizes the filter membrane channel during the product extraction stage so that the internal pressure of the filter membrane channel is higher than the liquid pressure of the anode chamber, so that water and iodine ions enter the anode chamber through the filter membrane channel, thereby increasing the concentration of the polysaccharide solution in the filter membrane channel and reducing the concentration of iodine ions in the polysaccharide solution, thereby improving the periodate regeneration efficiency and improving the separation and purification efficiency of dialdehyde polysaccharides and iodide.

[0019] The second aspect of the present invention provides a process for electrochemical catalytic polysaccharide oxidation, which is carried out using the electrochemical catalytic polysaccharide oxidation device described in the first aspect. The specific process method comprises the following steps:

[0020] Inject a polysaccharide solution into the filter membrane channel; inject a periodate solution into the anode chamber; start an electrochemical oxidation reaction, and simultaneously connect the first booster device to the anode chamber to increase the pressure of the anode chamber so that the periodate solution in the anode chamber enters the filter membrane channel and undergoes an electrochemical oxidation reaction with the polysaccharide solution to produce iodine-containing ions and dialdehyde polysaccharides; alternatively, shut down the electrochemical oxidation reaction, and simultaneously connect the first booster device to the filter membrane channel to increase the pressure of the filter membrane channel so that the iodine-containing ions and water in the filter membrane channel enter the anode chamber, thereby achieving separation of iodine-containing ions and dialdehyde polysaccharides.

[0021] Preferably, the condition for the periodate solution in the anode chamber to enter the filter membrane channel is: the pressure of the anode chamber is 0.1MPa~1MPa, and the pressure of the filter membrane channel is less than the pressure of the anode chamber; the condition for the iodide ions and water in the filter membrane channel to enter the anode chamber is: the pressure of the filter membrane channel is 0.1MPa~1MPa, and the pressure of the anode chamber is less than the pressure of the filter membrane channel.

[0022] Preferably, the process step of starting the electrochemical oxidation reaction and the process step of shutting down the electrochemical oxidation reaction are performed alternately to achieve cyclic production of electrochemically catalyzed polysaccharide oxidation.

[0023] Preferably, when executing the process step of shutting down the electrochemical oxidation reaction, after achieving the separation of iodine ions and dialdehyde polysaccharides, it also includes: extracting product liquid from the filter membrane channel, and then replenishing the polysaccharide solution into the filter membrane channel.

[0024] Beneficial effects of the present invention:

[0025] 1. The present invention can avoid moving all iodine-containing anions out of the anode chamber when extracting the product in the filter membrane channel by limiting the reactant polysaccharide and its oxidation product dialdehyde polysaccharide in the filter membrane channel, thereby improving the periodate regeneration efficiency and the separation and purification efficiency of dialdehyde polysaccharide and iodine-containing ions, and solving the problems of low periodate regeneration efficiency and low dialdehyde polysaccharide purification efficiency in the current cycle process of repeated oxidation of polysaccharides on electrodes. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic structural diagram of an electrochemical catalytic polysaccharide oxidation device provided in one embodiment of the present invention.

[0027] Figure 2 It is the reaction formula of the anode reaction, cathode reaction, reaction in the filter membrane channel and the overall reaction in Example 1.

[0028] Figure 3 It is a curve showing the sodium periodate regeneration efficiency and average current efficiency changing with the number of cycles at different times of adding materials in Example 1.

[0029] Figure 4 It is a curve showing the sodium periodate regeneration efficiency and average current efficiency changing with the number of cycles at different times of addition in Example 2.

[0030] Figure 5 It is a curve showing the sodium periodate regeneration efficiency and average current efficiency changing with the number of cycles at different times of addition in Example 3.

[0031] Description of reference numerals:

[0032] 1. Electrolytic cell; 2. Power supply; 3. Bipolar membrane; 4. Filter membrane channel; 5. First boosting device; 6. Second boosting device; 7. Anode; 8. Cathode; 9. First circulation loop solenoid valve; 10. Second circulation loop solenoid valve; 11. Anode chamber air pressure regulating solenoid valve; 12. Cathode chamber air pressure regulating solenoid valve; 13. First cathode chamber solenoid valve; 14. First anode chamber solenoid valve; 15. Second cathode chamber solenoid valve; 16. Second anode chamber solenoid valve; 17. Agitator. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0034] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

[0035] For simplicity, some numerical ranges are disclosed herein only by way of example. However, any lower limit can be combined with any other upper limit to form an unambiguous range; and any lower limit can be combined with other lower limits to form an unambiguous range, and any upper limit can be combined with any other upper limit to form an unambiguous range. In addition, although not explicitly stated, each point or single value between the range endpoints is included in the range. Therefore, each point or single value can be combined with any other point or single value as its own lower limit or upper limit, or with other lower limits or upper limits to form an unambiguous range. It should be understood that the enumeration of numerical values ​​is only for example and should not be interpreted as exhaustive.

[0036] In the description of this article, it should be noted that, unless otherwise specified, "above", "below", "≤", and "≥" all include the number itself, "at least one" means including one or more, and the "multiple" in "one or more" means two or more.

[0037] At present, for the preparation of dialdehyde polysaccharides, in order to recycle periodate, the reaction between periodate and polysaccharides is mainly limited to the anode chamber of the electrolytic cell, and the polysaccharides and periodate ions are confined in the anode chamber through a cation exchange membrane. The iodate ions obtained after the polysaccharides are oxidized by periodate ions are re-oxidized to periodate ions at the anode through an electrochemical reaction, thereby converting the traditional one-time oxidation of polysaccharides by periodate into a cyclic process of repeated oxidation of polysaccharides on the electrode.

[0038] However, the current repeated oxidation of polysaccharides on the electrode cycle process limits the regeneration efficiency of periodate. This is mainly due to the current method of placing the polysaccharide solution and the periodate ion solution in the same space. Therefore, when the product polysaccharide / dialdehyde polysaccharide solution is removed from the anode chamber, the polysaccharide / dialdehyde polysaccharide is in a uniformly mixed state with a variety of iodide-containing ions, resulting in the loss of periodate ions as the product is transferred out of the electrolytic cell, reducing the regeneration efficiency of the periodate ions. Moreover, the various iodide-containing ions mixed with the product solution further lead to the problem of low dialdehyde polysaccharide purification efficiency.

[0039] In order to solve the problems of low periodate regeneration efficiency and low dialdehyde polysaccharide purification efficiency in the current cyclic process of repeated oxidation of polysaccharides on electrodes, the present invention confines the reactant polysaccharide and its oxidation product dialdehyde polysaccharide in the filter membrane channel, thereby avoiding moving all iodine-containing anions out of the anode chamber when extracting the product in the filter membrane channel, thereby improving the periodate regeneration efficiency and the separation and purification efficiency of dialdehyde polysaccharide and iodine-containing ions.

[0040] In addition, by pressurizing the filter membrane channel during the product extraction stage, the internal pressure of the filter membrane channel is made higher than the liquid pressure in the anode chamber, so that water and iodine ions enter the anode chamber through the filter membrane channel, thereby increasing the concentration of the polysaccharide solution in the filter membrane channel and reducing the concentration of iodine ions in the polysaccharide solution, thereby improving the regeneration efficiency of periodate and improving the separation and purification efficiency of dialdehyde polysaccharides and iodide.

[0041] Based on this, the present invention spatially restricts periodate ions and polysaccharides, so that periodate has better economy and can effectively improve the efficiency and purity of the dialdehyde polysaccharide purification process.

[0042] like Figure 1 , an electrochemical catalytic polysaccharide oxidation device, comprising an electrolytic cell 1, the electrolytic cell 1 comprising an anode chamber and a cathode chamber and a bipolar membrane 3 separating the anode chamber and the cathode chamber, a filter membrane channel 4 is arranged in the anode chamber, a polysaccharide solution is injected into the filter membrane channel 4, and a periodate solution is injected into the anode chamber; the filter membrane channel 4 can allow the periodate solution to pass through and react with the polysaccharide solution through an electrochemical oxidation reaction, and can allow iodine-containing ions produced by the electrochemical oxidation reaction to pass through and enter the anode chamber.

[0043] Specifically, in one embodiment of the present invention, the electrochemical oxidation reaction of the polysaccharide is confined within the filter membrane channel 4, and the iodine-containing ions participating in the electrochemical oxidation reaction can selectively penetrate the filter membrane channel 4 into the anode chamber through concentration diffusion, pressure diffusion or electrophoresis between the anode chamber and the filter membrane channel, or enter the filter membrane channel from the anode chamber. One embodiment of the present invention is mainly to confine the reactant polysaccharide and its oxidation product dialdehyde polysaccharide within the filter membrane channel 4, while the iodine-containing ions penetrate the filter membrane channel 4 into the anode chamber. Thus, when extracting the product in the filter membrane channel 4, it is possible to avoid removing all iodine-containing anions from the electrochemical catalytic polysaccharide oxidation device, thereby improving the periodate regeneration efficiency, and improving the separation and purification efficiency of dialdehyde polysaccharides and iodine-containing ions, and solving the problem of low periodate regeneration efficiency and low dialdehyde polysaccharide purification efficiency in the current cyclic process of repeatedly oxidizing polysaccharides on electrodes.

[0044] Specifically, the electrochemical catalytic polysaccharide oxidation device includes an electrolytic cell 1 and a power supply 2. The electrolytic cell 1 includes an anode chamber and a cathode chamber and a bipolar membrane separating the anode chamber and the cathode chamber, wherein an anode 7 is arranged in the anode chamber and a cathode 8 is arranged in the cathode chamber; the anode 7 is connected to the positive pole of the power supply, and the cathode 8 is connected to the negative pole of the power supply. The bipolar membrane 3 includes a cation exchange membrane and an anion exchange membrane, wherein the cation exchange membrane is placed in the anode chamber and the anion exchange membrane is placed in the cathode chamber. A stirrer 17 is arranged in the anode chamber.

[0045] On the basis of the above embodiment, as a more preferred embodiment, the electrochemical catalytic polysaccharide oxidation device includes a first booster 5 and a second booster 6, wherein the first booster 5 is connected to the filter membrane channel 4 to adjust the pressure in the filter membrane channel 4. The second booster 6 is connected to the anode chamber to adjust the pressure in the anode chamber.

[0046] Specifically, the first pressure increasing device 5 is connected to the filter membrane channel 4 and is used to adjust the pressure of the filter membrane channel 4, thereby forming a positive pressure difference between the filter membrane channel and the anode chamber, that is, the internal pressure of the filter membrane channel 4 is higher than the liquid pressure of the anode chamber. By pressurizing the filter membrane channel 4 in the product extraction stage, the internal pressure of the filter membrane channel 4 is higher than the liquid pressure of the anode chamber, so that water and iodine ions enter the anode chamber through the filter membrane channel 4, thereby increasing the concentration of the polysaccharide solution in the filter membrane channel 4 and reducing the concentration of iodine ions in the polysaccharide solution, thereby improving the regeneration efficiency of periodate and improving the separation and purification efficiency of dialdehyde polysaccharides and iodide.

[0047] The second pressurizing device 6 is connected to the anode chamber and is used to adjust the pressure of the anode chamber, thereby forming a positive pressure difference between the anode chamber and the filter membrane channel, that is, the liquid pressure in the anode chamber is greater than the internal pressure of the filter membrane channel 4. By pressurizing the anode chamber during the electrochemical oxidation reaction stage, the periodate solution in the anode chamber can pass through the filter membrane channel 4, enter the filter membrane channel 4, and undergo an electrochemical oxidation reaction with the polysaccharide solution in the filter membrane channel 4 to produce iodine ions and dialdehyde polysaccharides.

[0048] Specifically, one embodiment of the present invention spatially restricts periodate ions and polysaccharides, thereby making periodate more economical, significantly improving the regeneration efficiency of periodate ions, increasing the yield of the product dialdehyde polysaccharide solution, and reducing the cost of dialdehyde polysaccharide purification.

[0049] On the basis of the above-mentioned embodiment, as a more preferred embodiment, the filter membrane pore size of the filter membrane channel 4 satisfies the following conditions: the molecular weight cutoff of the filter membrane channel 4 is between 500 and 100,000; the molecular weight cutoff of the filter membrane channel 4 is smaller than the molecular weight of the polysaccharide in the polysaccharide solution; the molecular weight cutoff of the filter membrane channel 4 is smaller than the molecular weight of the dialdehyde polysaccharide produced by the electrochemical oxidation reaction.

[0050] In one embodiment of the present invention, the molecular weight cutoff of the filter membrane channel 4 is less than the molecular weight of the dialdehyde polysaccharide, thereby enabling the oxidation product dialdehyde polysaccharide to be confined within the filter membrane channel 4. The molecular weight cutoff of the filter membrane channel 4 is less than the molecular weight of the polysaccharide in the polysaccharide solution, thereby enabling the reactant polysaccharide to be confined within the filter membrane channel 4.

[0051] Preferably, the molecular weight of the polysaccharide in the polysaccharide solution is 5000-10000000; the molecular weight of the dialdehyde polysaccharide produced by the electrochemical oxidation reaction is 4000-8000000.

[0052] Preferably, the pore size of the filter membrane channel 4 is 1 nm to 50 nm.

[0053] In one embodiment of the present invention, the pore size of the filter membrane should not be too large or too small. The pore size of the filter membrane is characterized by the average molecular weight of the molecules that can pass through it. When the filter membrane has too high molecular permeability, it will cause too much polysaccharide and dialdehyde polysaccharide whose molecular weight has become smaller due to oxidation to diffuse from the filter membrane channel into the anode chamber, resulting in the loss of product dialdehyde polysaccharide and low separation efficiency from iodine-containing ions. When the filter membrane has too low molecular permeability, it will also reduce the iodine-containing IO 4- ,IO 3- ,I -The rate at which polysaccharides pass through the filter membrane channel under pressure or without pressure, thereby affecting the oxidized polysaccharides entering the filter membrane channel from the anode chamber. For example, the molecular weight cutoff of the filter membrane can be 500, 1000, 1200, 1500, 2000, 2500, 3000, 3500, 4000, 4500, 5000, 5500, 6000, 6500, 7000, 7500, 8000, 8200, 8500, 9000, 9500, 10000, 11000, 12000 000, 13000, 14000, 15000, 16000, 17000, 18000, 19000, 20000, 25000, 50000, 100000, etc., including all ranges and sub-ranges therein, for example, 1000-10000, 1000-20000, 1000-25000, 1200-10000.

[0054] Table 1 The approximate correspondence between the molecular weight cutoff and pore size of the filter channel, as well as the molecular weight of polysaccharides and their corresponding oxidation products - dialdehyde polysaccharides that can be effectively retained by the filter membrane of this specification

[0055] serial number Molecular weight cut-off of the membrane channel Membrane pore size Molecular weight of polysaccharides / dialdehyde polysaccharides 1 500 1.3nm >750 2 3000 2.4nm >4500 3 10000 3.5nm >15000 4 100000 7.5nm >150000

[0056] Note: Effective retention in the filter membrane channel means the number of retained molecules / total number of molecules>95%.

[0057] On the basis of the above embodiment, as a more preferred embodiment, the filter membrane material of the filter membrane channel 4 is at least one of aluminum oxide membrane, zirconium dioxide membrane, silicon carbide membrane, silicon dioxide membrane, titanium dioxide membrane, cellulose acetate membrane, cellulose acetate ester membrane, cellulose triacetate membrane, polyethylene membrane, polypropylene membrane, polybutylene membrane, polyvinylidene fluoride membrane, polytetrafluoroethylene membrane, polysulfone membrane, polyethersulfone membrane, sulfonated polyethersulfone membrane, polyacrylonitrile resin membrane, polyimide membrane, polyamide membrane, and polyaryletherketone membrane.

[0058] Preferably, the periodate is at least one of metaperiodic acid, orthoperiodic acid, potassium metaperiodate, sodium metaperiodate, sodium orthoperiodate, potassium orthoperiodate, potassium diorthoperiodate, sodium diorthoperiodate, sodium paraperiodate, potassium paraperiodate, potassium dimetaperiodate, and sodium dimetaperiodate; the polysaccharide is a polysaccharide having a vicinal diol group, and the polysaccharide is at least one of alginic acid, alginate, hyaluronic acid, hyaluronate, starch, glycogen, dextran, pectin, agar, and cellulose, or a derivative thereof.

[0059] Preferably, the concentration of the polysaccharide solution is 0.05 w / v% to 15 w / v%; the concentration of the periodate solution is 0.01M to 2M.

[0060] In one embodiment of the present invention, by placing a polysaccharide solution in the filter membrane channel of the electrochemical device and injecting a periodate solution into the anode chamber, the polysaccharide solution will undergo an electrochemical oxidation reaction at a certain voltage to generate a dialdehyde polysaccharide product. By adjusting the voltage, the anode chamber pressure, and the filter membrane channel pressure, the regeneration efficiency of sodium periodate and the yield of dialdehyde polysaccharides can be improved. Preferably, the voltage difference of the electrolytic cell is 1V to 4V, and the current is 1mA / cm 2 ~100mA / cm 2 .

[0061] On the basis of the above-mentioned embodiment, the above-mentioned electrochemical catalytic polysaccharide oxidation device is used to perform electrochemical catalytic polysaccharide oxidation.

[0062] A process for electrochemical catalytic polysaccharide oxidation comprises the following steps:

[0063] The polysaccharide solution is injected into the filter membrane channel; and the periodate solution is injected into the anode chamber.

[0064] The electrochemical oxidation reaction is started, and the second pressurizing device 6 is started to increase the pressure of the anode chamber so that the periodate solution in the anode chamber enters the filter membrane channel and undergoes an electrochemical oxidation reaction with the polysaccharide solution to produce iodine ions and dialdehyde polysaccharides.

[0065] Alternatively, the electrochemical oxidation reaction is turned off, and the first pressure-increasing device 5 is started to increase the pressure of the filter membrane channel so that the iodine-containing ions and water in the filter membrane channel enter the anode chamber to achieve the separation of the iodine-containing ions and the dialdehyde polysaccharide.

[0066] On the basis of the above embodiment, as a more preferred embodiment, the condition for the periodate solution in the anode chamber to enter the filter membrane channel is: the pressure of the filter membrane channel is 0.1MPa to 1MPa, and the pressure of the filter membrane channel is less than the pressure of the anode chamber.

[0067] The conditions for the iodine ions and water in the filter membrane channel to enter the anode chamber are: the pressure of the anode chamber is 0.1MPa to 1MPa, and the pressure of the anode chamber is less than the pressure of the filter membrane channel.

[0068] Preferably, the process step of starting the electrochemical oxidation reaction and the process step of shutting down the electrochemical oxidation reaction are performed alternately to achieve cyclic production of electrochemically catalyzed polysaccharide oxidation.

[0069] On the basis of the above-mentioned embodiment, as a more preferred embodiment, when executing the process step of shutting down the electrochemical oxidation reaction, after achieving the separation of iodine ions and dialdehyde polysaccharides, it also includes: extracting product liquid from the filter membrane channel, and then replenishing the polysaccharide solution into the filter membrane channel.

[0070] The technical solution of the present invention is further described below through specific embodiments.

[0071] In the following examples, the methods described are conventional methods unless otherwise specified; the reagents and materials described are commercially available unless otherwise specified.

[0072] Example 1

[0073] Use containing Figure 1 The electrochemical catalytic polysaccharide oxidation device of the filter membrane channel shown in the figure is used to prepare oxidized sodium alginate, and the anode chamber and the filter membrane channel are not pressurized separately. The specific process method includes the following steps:

[0074] Step 1, using a polyamide membrane with a molecular weight cutoff of 500 as a filter membrane material, adding 100 ml of 0.6M sodium periodate aqueous solution into the anode chamber of the electrolytic cell; injecting 100 ml of 1.0wt% sodium alginate aqueous solution into the filter membrane channel, wherein the viscosity of the 1wt% sodium alginate aqueous solution is 15cP-25cP, and there are two unit structures in sodium alginate, namely β-D-mannuronic acid and α-L-guluronic acid; wherein the number of β-D-mannuronic acid units: the number of α-L-guluronic acid units = 1:1; and adding 100 ml of water into the cathode chamber.

[0075] Step 2: insert a graphite felt anode and a platinum cathode into the electrolytic cell, set the electrolysis voltage to 2.5V, the current to a constant current of 80mA, and react at room temperature for 1 hour under stirring.

[0076] Step 3, extracting the product liquid containing oxidized sodium alginate from the filter membrane channel.

[0077] Step 4, add 100 ml of 1.0 wt% sodium alginate into the filter membrane channel.

[0078] Step 5. Repeat steps 2 to 4 five times.

[0079] Step 6, ultrafiltering the product liquid, and vacuum freeze-drying to obtain purified oxidized sodium alginate.

[0080] Figure 2 It is the reaction formula of the anode reaction, cathode reaction, reaction in the filter membrane channel and the overall reaction in Example 1. Figure 3 It is a curve showing the sodium periodate regeneration efficiency and average current efficiency changing with the number of cycles at different times of adding materials in Example 1.

[0081] According to calculation, the average yield of oxidized sodium alginate is 89% and the oxidation degree is 21%.

[0082] The average regeneration efficiency of sodium periodate in the process is 82%.

[0083] The average current efficiency is 63%.

[0084] Example 2

[0085] Use containing Figure 1 The electrochemical catalytic polysaccharide oxidation device of the filter membrane channel and the pressurizing device shown in the figure is used to prepare oxidized sodium alginate. After adjusting the voltage and pressurizing the anode chamber and the filter membrane channel respectively, the preparation efficiency of oxidized sodium alginate and the regeneration efficiency of periodate can be further improved. The specific process method includes the following steps:

[0086] Step 1, using a polyamide membrane with a molecular weight cutoff of 500 as the filter membrane material, 100 ml of 0.6M sodium periodate aqueous solution is added to the anode chamber of the electrolytic cell. 100 ml of 1.0wt% sodium alginate aqueous solution is injected into the filter membrane channel, wherein the viscosity of the 1.0wt% sodium alginate aqueous solution is 15cP-25cP, and there are two unit structures in sodium alginate, namely β-D-mannuronic acid and α-L-guluronic acid; wherein the number of β-D-mannuronic acid units: the number of α-L-guluronic acid units = 1:1. 100 ml of water is added to the cathode chamber.

[0087] Step 2, inserting a graphite felt anode and a platinum cathode into the reactor, setting the electrolysis voltage to 2.5V, the current to a constant current of 80mA, pressurizing the anode chamber to 0.20MPa, reacting at room temperature for 1 hour under stirring conditions, and using a circulating booster pump to set the flow rate of the polysaccharide solution to 10 ml / s.

[0088] Step 3, stop the electrolysis, and use the second pressurizing device 6 to pressurize the anode chamber to 0.30 MPa for 1 hour.

[0089] Step 4, stop pressurizing the anode chamber, open the gas valve in the anode chamber to balance the internal and external air pressures to 0.10 MPa, use the first booster 5 to increase the pressure in the filter membrane channel to 0.50 MPa, the flow rate is 30 ml / s, and after circulating for 20 minutes, extract the product liquid containing oxidized sodium alginate from the filter membrane channel.

[0090] Step 5. Repeat steps 2 to 4 five times.

[0091] Step 6, ultrafiltering the product liquid, and vacuum freeze-drying to obtain purified oxidized sodium alginate.

[0092] Figure 4 It is a curve showing the sodium periodate regeneration efficiency and average current efficiency changing with the number of cycles at different times of addition in Example 2.

[0093] It has been calculated that the average yield of oxidized sodium alginate is 92% and the oxidation degree is 25%.

[0094] The average regeneration efficiency of sodium periodate in the process is 85%.

[0095] The average current efficiency is 65%.

[0096] Example 3

[0097] Use containing Figure 1 The electrochemical catalytic polysaccharide oxidation device of the filter membrane channel and the booster device shown in the figure is used to prepare the oxidized sodium hyaluronate. With the support of the filter membrane channel, various sodium hyaluronates containing ortho-dihydroxy groups can be electrochemically oxidized. Taking sodium hyaluronate as an example, the specific process method includes the following steps:

[0098] Step 1, using a polyamide membrane with a molecular weight cutoff of 500 as the filter membrane material, 100 ml of 0.8M sodium periodate aqueous solution is added to the anode chamber of the electrolytic cell. 100 ml of 1.0 wt% sodium hyaluronate (molecular weight: 100,000) aqueous solution is injected into the filter membrane channel, and the molecular weight of sodium hyaluronate is 100,000. 100 ml of water is added to the cathode chamber.

[0099] Step 2, insert a graphite felt anode and a platinum cathode into the reactor, set the electrolysis voltage to 2.4V, the current to a constant current of 90mA, pressurize the anode chamber to 0.25MPa, react at room temperature for 1 hour under stirring conditions, and use a circulating booster pump to set the flow rate of the sodium hyaluronate solution to 15 ml / s.

[0100] Step 3, stop the electrolysis, and use the second pressurizing device 6 to pressurize the anode chamber to 0.40 MPa for 30 minutes.

[0101] Step 4, stop pressurizing the anode chamber, open the gas valve in the anode chamber to balance the internal and external air pressures to 0.10 MPa, use the first booster 5 to increase the pressure in the filter membrane channel to 0.50 MPa, the flow rate is 30 ml / s, and after circulating for 20 minutes, extract the product liquid containing oxidized sodium hyaluronate from the filter membrane channel.

[0102] Step 5. Repeat steps 2 to 4 five times.

[0103] Step 6, ultrafiltering the product liquid, and vacuum freeze-drying to obtain purified oxidized sodium hyaluronate.

[0104] Figure 5 It is a curve showing the sodium periodate regeneration efficiency and average current efficiency changing with the number of cycles at different times of addition in Example 3.

[0105] It has been calculated that the average yield of oxidized sodium hyaluronate is 82% and the degree of oxidation is 19%.

[0106] The average regeneration efficiency of sodium periodate in the process is 85%.

[0107] The average current efficiency is 55%.

[0108] Example 4

[0109] Use containing Figure 1 The electrochemical catalytic polysaccharide oxidation device of the filter membrane channel and the booster device shown in the figure is used to prepare oxidized sodium alginate. With the support of the filter membrane channel, various sodium alginate containing ortho-dihydroxyl groups can be electrochemically oxidized. Taking polyethersulfone membrane as the filter membrane material as an example, the specific process method includes the following steps:

[0110] Step 1, using a polyethersulfone membrane with a molecular weight cutoff of 3000 as a filter membrane material, adding 100 ml of 0.8M sodium periodate aqueous solution into the anode chamber of the electrolytic cell; injecting 100 ml of 2.0wt% sodium alginate aqueous solution into the filter membrane channel, wherein the viscosity of the 1wt% sodium alginate aqueous solution is 15cP-25cP, and the number of α-L-guluronic acid units: the number of β-D-mannuronic acid units = 1:1; and adding 100 ml of water into the cathode chamber.

[0111] Step 2: insert a graphite felt anode and a platinum cathode into the electrolytic cell, set the electrolysis voltage to 2.5V, the current to a constant current of 80mA, and react at room temperature for 2 hours under stirring.

[0112] Step 3, extracting the product liquid containing oxidized sodium alginate from the filter membrane channel.

[0113] Step 4, add 100 ml of 2.0 wt% sodium alginate into the filter membrane channel.

[0114] Step 5. Repeat steps 2 to 4 five times.

[0115] Step 6, ultrafiltering the product liquid, and vacuum freeze-drying to obtain purified oxidized sodium alginate.

[0116] It has been calculated that the average yield of oxidized sodium alginate is 87% and the oxidation degree is 24%.

[0117] The average regeneration efficiency of sodium periodate in the process is 81%.

[0118] The average current efficiency is 60%.

[0119] Example 5

[0120] Use containing Figure 1 The electrochemical catalytic polysaccharide oxidation device of the filter membrane channel and the booster device shown in the figure is used to prepare oxidized sodium alginate. With the support of the filter membrane channel, various sodium alginate containing ortho-dihydroxyl groups can be electrochemically oxidized. Taking polyvinylidene fluoride as the filter membrane material as an example, the specific process method includes the following steps:

[0121] Step 1, using a polyvinylidene fluoride membrane with a molecular weight cutoff of 3000 as a filter membrane material, adding 100 ml of 0.6M sodium periodate aqueous solution into the anode chamber of the electrolytic cell; injecting 100 ml of 1.0wt% sodium alginate aqueous solution into the filter membrane channel, wherein the viscosity of the 1wt% sodium alginate aqueous solution is 15cP~25cP, and the number of α-L-guluronic acid units: the number of β-D-mannuronic acid units = 1:1; and adding 100 ml of water into the cathode chamber.

[0122] Step 2: insert a graphite felt anode and a platinum cathode into the electrolytic cell, set the electrolysis voltage to 2.5V, the current to a constant current of 80mA, and react at room temperature for 1 hour under stirring.

[0123] Step 3, extracting the product liquid containing oxidized sodium alginate from the filter membrane channel.

[0124] Step 4, add 100 ml of 1.0 wt% sodium alginate into the filter membrane channel.

[0125] Step 5. Repeat steps 2 to 4 five times.

[0126] Step 6, ultrafiltering the product liquid, and vacuum freeze-drying to obtain purified oxidized sodium alginate.

[0127] According to calculation, the average yield of oxidized sodium alginate is 85% and the oxidation degree is 25%.

[0128] The average regeneration efficiency of sodium periodate in the process is 79%.

[0129] The average current efficiency is 58%.

[0130] Example 6

[0131] Use containing Figure 1 The electrochemical catalytic polysaccharide oxidation device of the filter membrane channel and the booster device shown in the figure is used to prepare oxidized sodium alginate. With the support of the filter membrane channel, various sodium alginates containing ortho-dihydroxyl groups can be electrochemically oxidized. Taking potassium periodate as an example, the specific process method includes the following steps:

[0132] Step 1, using a polyamide membrane with a molecular weight cutoff of 500 as a filter membrane material, adding 100 ml of 0.6M potassium periodate aqueous solution into the anode chamber of the electrolytic cell; injecting 100 ml of 1.0wt% sodium alginate aqueous solution into the filter membrane channel, wherein the viscosity of the 1wt% sodium alginate aqueous solution is 15cP-25cP, and there are two unit structures in sodium alginate, namely β-D-mannuronic acid and α-L-guluronic acid; wherein the number of α-L-guluronic acid units: the number of β-D-mannuronic acid units = 1:1; and adding 100 ml of water into the cathode chamber.

[0133] Step 2: insert a graphite felt anode and a platinum cathode into the electrolytic cell, set the electrolysis voltage to 2.5V, the current to a constant current of 80mA, and react at room temperature for 1 hour under stirring.

[0134] Step 3, extracting the product liquid containing oxidized sodium alginate from the filter membrane channel.

[0135] Step 4, add 100 ml of 1.0 wt% sodium alginate into the filter membrane channel.

[0136] Step 5. Repeat steps 2 to 4 five times.

[0137] Step 6, ultrafiltering the product liquid, and vacuum freeze-drying to obtain purified oxidized sodium alginate.

[0138] According to calculation, the average yield of oxidized sodium alginate is 88% and the oxidation degree is 22%.

[0139] The average regeneration efficiency of potassium periodate in the process is 80%.

[0140] The average current efficiency is 64%.

[0141] Example 7

[0142] Use containing Figure 1 The electrochemical catalytic polysaccharide oxidation device of the filter membrane channel and the booster device shown in the figure is used to prepare oxidized starch. With the support of the filter membrane channel, various starches containing ortho-dihydroxyl groups can be electrochemically oxidized. Taking starch as the polysaccharide raw material as an example, the specific process method includes the following steps:

[0143] Step 1, using a polyamide membrane with a molecular weight cutoff of 500 as the filter membrane material, adding 100 ml of 0.6M sodium periodate aqueous solution into the anode chamber of the electrolytic cell; injecting 100 ml of 1.0wt% starch solution into the filter membrane channel, wherein the linear content is ≥70% and the average molecular weight is 1000000; and adding 100 ml of water into the cathode chamber.

[0144] Step 2: insert a graphite felt anode and a platinum cathode into the electrolytic cell, set the electrolysis voltage to 2.5V, the current to a constant current of 80mA, and react at room temperature for 1 hour under stirring.

[0145] Step 3, extracting the product liquid containing oxidized starch from the filter membrane channel.

[0146] Step 4, add 100 ml of 1.0 wt% amylose into the filter membrane channel.

[0147] Step 5. Repeat steps 2 to 4 five times.

[0148] Step 6, ultrafiltering the product liquid, and vacuum freeze-drying to obtain purified oxidized amylose.

[0149] According to calculation, the average yield of oxidized amylose is 75% and the oxidation degree is 14%.

[0150] The average regeneration efficiency of sodium periodate in the process is 89%.

[0151] The average current efficiency is 53%.

[0152] Example 8

[0153] Use containing Figure 1 The electrochemical catalytic polysaccharide oxidation device with the filter membrane channel and the booster device shown is used to prepare oxidized dextran. With the support of the filter membrane channel, various dextran containing ortho-dihydroxyl groups can be electrochemically oxidized. Taking dextran as a polysaccharide as an example, the specific process method includes the following steps:

[0154] Step 1, using a polyamide membrane with a molecular weight cutoff of 500 as the filter membrane material, adding 100 ml of 0.6M sodium periodate aqueous solution into the anode chamber of the electrolytic cell; injecting 100 ml of 1.0wt% dextran solution with a molecular weight of 100000 into the filter membrane channel; and adding 100 ml of water into the cathode chamber.

[0155] Step 2: insert a graphite felt anode and a platinum cathode into the electrolytic cell, set the electrolysis voltage to 2.5V, the current to a constant current of 80mA, and react at room temperature for 1 hour under stirring.

[0156] Step 3, extracting the product liquid containing oxidized dextran from the filter membrane channel.

[0157] Step 4, add 100 ml of 1.0 wt% dextran to the filter membrane channel.

[0158] Step 5. Repeat steps 2 to 4 five times.

[0159] Step 6, ultrafiltering the product liquid, and vacuum freeze-drying to obtain purified oxidized dextran.

[0160] According to calculation, the average yield of oxidized amylose is 70% and the oxidation degree is 20%.

[0161] The average regeneration efficiency of sodium periodate in the process is 83%.

[0162] The average current efficiency is 59%.

[0163] Table 2 Electrochemical catalytic oxidation of different polysaccharides

[0164]

[0165]

[0166] Note: Periodate is sodium periodate.

[0167] Table 3 Comparison of electrochemical catalytic oxidation results of different polysaccharides

[0168]

[0169]

[0170] According to Table 2 and Table 3, compared with Example 1, Example 2 can further improve the yield and oxidation degree of oxidized sodium alginate and the regeneration efficiency of periodate by pressurizing the anode chamber and the filter membrane channel respectively.

[0171] In Example 3, the anode chamber and the filter membrane channel were pressurized separately. The average yield of oxidized sodium hyaluronate was 82% and the oxidation degree was 19%. The regeneration efficiency of periodate was close to that of other examples, and the current efficiency was also close, which proved that the device is suitable for sodium hyaluronate.

[0172] Example 4 used a polyethersulfone membrane with a molecular weight cutoff of 3000. Compared with Example 1, the larger molecular weight cutoff in Example 4 accelerated the speed at which periodate ions passed through the filter membrane and increased the degree of oxidation. However, due to its large molecular weight cutoff, the yield, regeneration efficiency and current efficiency all decreased.

[0173] Example 5 used a polyvinylidene fluoride membrane with a molecular weight cutoff of 3000. Compared with Example 1, the larger molecular weight cutoff in Example 5 accelerated the speed at which periodate ions passed through the filter membrane and increased the degree of oxidation of the product. However, due to its large molecular weight cutoff, the yield, regeneration efficiency and current efficiency all decreased.

[0174] Example 6 uses potassium periodate as the periodate source. Compared with Example 1, the values ​​are quite close, which proves that the electrochemical device is also effective when using periodates other than sodium periodate.

[0175] The results of Example 7 prove that the oxidation effect of the electrochemical device on starch is similar to that of other examples and has practical value.

[0176] The results of Example 8 prove that the electrochemical device has a similar oxidation effect on dextran as other examples and has practical value.

[0177] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An electrochemical catalytic polysaccharide oxidation device, comprising an electrolytic cell (1), wherein the electrolytic cell (1) comprises an anode chamber and a cathode chamber and a bipolar membrane (3) separating the anode chamber and the cathode chamber, characterized in that: A filter membrane channel (4) is arranged in the anode chamber, a polysaccharide solution is injected into the filter membrane channel (4), and a periodate solution is injected into the anode chamber; The filter membrane channel (4) is capable of allowing the periodate solution to pass through and undergo an electrochemical oxidation reaction with the polysaccharide solution, and is capable of allowing the iodine-containing ions produced by the electrochemical oxidation reaction to pass through and enter the anode chamber.

2. The electrochemical catalytic polysaccharide oxidation device according to claim 1, characterized in that: The filter membrane pore size of the filter membrane channel (4) satisfies the following conditions: The molecular weight cut-off of the filter membrane channel (4) is between 500 and 100,000; The molecular weight cutoff of the filter membrane channel (4) is smaller than the molecular weight of the polysaccharide in the polysaccharide solution; the molecular weight cutoff of the filter membrane channel (4) is smaller than the molecular weight of the dialdehyde polysaccharide produced by the electrochemical oxidation reaction.

3. The electrochemical catalytic polysaccharide oxidation device according to claim 2, characterized in that: The molecular weight of the polysaccharide in the polysaccharide solution is 5000 to 10000000; The molecular weight of the dialdehyde polysaccharide produced by the electrochemical oxidation reaction is 4,000 to 8,000,000.

4. The electrochemical catalytic polysaccharide oxidation device according to claim 2, characterized in that: The filter membrane pore size of the filter membrane channel (4) is 1 nm to 50 nm.

5. The electrochemical catalytic polysaccharide oxidation device according to claim 4, characterized in that: The filter membrane material of the filter membrane channel (4) is at least one of aluminum oxide membrane, zirconium dioxide membrane, silicon carbide membrane, silicon dioxide membrane, titanium dioxide membrane, cellulose acetate membrane, cellulose acetate ester membrane, cellulose triacetate membrane, polyethylene membrane, polypropylene membrane, polybutylene membrane, polyvinylidene fluoride membrane, polytetrafluoroethylene membrane, polysulfone membrane, polyethersulfone membrane, sulfonated polyethersulfone membrane, polyacrylonitrile resin membrane, polyimide membrane, polyamide membrane, and polyaryletherketone membrane.

6. The electrochemical catalytic polysaccharide oxidation device according to claim 1, characterized in that: The periodate is at least one of metaperiodic acid, orthoperiodic acid, potassium metaperiodate, sodium metaperiodate, sodium orthoperiodate, potassium orthoperiodate, potassium diorthoperiodate, sodium diorthoperiodate, sodium paraperiodate, potassium paraperiodate, potassium dimetaperiodate, and sodium dimetaperiodate; The polysaccharide is a polysaccharide having a vicinal diol group, and the polysaccharide is at least one of alginic acid, alginate, hyaluronic acid, hyaluronate, starch, glycogen, dextran, pectin, agar, cellulose or a derivative thereof.

7. The electrochemical catalytic polysaccharide oxidation device according to claim 1, characterized in that: The concentration of the polysaccharide solution is 0.05 w / v% to 15 w / v%; the concentration of the periodate solution is 0.01M to 2M.

8. The electrochemical catalytic polysaccharide oxidation device according to claim 1, characterized in that: The electrochemical catalytic polysaccharide oxidation device comprises a first pressure boosting device (5) and a second pressure boosting device (6), wherein the first pressure boosting device (5) is connected to the filter membrane channel (4) to adjust the pressure of the filter membrane channel (4); The second pressure increasing device (6) is connected to the anode chamber to adjust the pressure of the anode chamber.

9. A process for electrochemical catalytic oxidation of polysaccharides, characterized in that: The electrochemical catalytic polysaccharide oxidation device according to claim 8 is used, and the specific process method comprises the following steps: Injecting a polysaccharide solution into the filter membrane channel (4); injecting a periodate solution into the anode chamber; Starting the electrochemical oxidation reaction, starting the second pressure increasing device (6), increasing the pressure of the anode chamber, so that the periodate solution in the anode chamber enters the filter membrane channel and undergoes an electrochemical oxidation reaction with the polysaccharide solution to produce iodine ions and dialdehyde polysaccharides; Alternatively, the electrochemical oxidation reaction is turned off, and the first pressure-increasing device (5) is started to increase the pressure of the filter membrane channel (4) so ​​that the iodine-containing ions and water in the filter membrane channel (4) enter the anode chamber, thereby achieving the separation of the iodine-containing ions and the dialdehyde polysaccharide.

10. The electrochemical catalytic polysaccharide oxidation process according to claim 9, characterized in that: The conditions for the periodate solution in the anode chamber to enter the filter membrane channel are: the pressure of the anode chamber is 0.1 MPa to 1 MPa, and the pressure of the filter membrane channel (4) is less than the pressure of the anode chamber; The conditions for the iodine ions and water in the filter membrane channel (4) to enter the anode chamber are: the pressure of the filter membrane channel (4) is 0.1 MPa to 1 MPa, and the pressure of the anode chamber is lower than the pressure of the filter membrane channel (4).

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