Anode plate of a reactor used for electrocatalysis of high concentrations of 5-hydroxymethylfurfural

Abstract

This invention discloses an anode plate for a reactor used in the electrocatalytic production of high-concentration 5-hydroxymethylfurfural. One end face of the anode plate is provided with a heart-shaped static mixing structure and a flow channel field, while the other end face is provided with an integrated cooling chamber structure. The flow channel field is a multi-channel serpentine flow channel field. The heart-shaped static mixing structure includes multiple spaced heart-shaped mixing tanks, with adjacent heart-shaped mixing tanks connected by transition tanks. The integrated cooling chamber structure includes a cooling tank and multiple flow channel ridges disposed within the cooling tank, with the multiple flow channel ridges arranged in an alternating pattern. The heart-shaped static mixing structure of this invention enables efficient in-situ mixing and rapid electro-oxidation of 5-hydroxymethylfurfural solution and alkaline electrolyte in the electrolytic cell, shortening the time of chemical side reactions. The integrated cooling chamber structure promotes efficient heat transfer during electrolysis, slowing down the rate of chemical side reactions. Together, these two components enable the selective oxidation of high-concentration 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid, improving product yield.

Description

Technical Field

[0001] This invention belongs to the field of biomass catalytic conversion and chemical engineering, and specifically relates to an anode plate for a reactor used for electrocatalytic high-concentration 5-hydroxymethylfurfural. Background Technology

[0002] Upgrading 5-hydroxymethylfurfural to a high-value industrial raw material through oxidation will contribute to the current transformation of the traditional petrochemical industry towards green and renewable resources. 2,5-Furandicarboxylic acid, a biomass-based green chemical platform molecule produced by the oxidation of 5-hydroxymethylfurfural, holds promise as a potential replacement for terephthalic acid and a fundamental raw material for the synthesis of polyethylene 2,5-furandicarboxylate.

[0003] The non-Radida side reactions of 5-hydroxymethylfurfural in alkaline solution pose a key challenge to the large-scale production of 2,5-furandicarboxylic acid. While increasing the concentrations of 5-hydroxymethylfurfural and the base can increase the current density for the oxidation of 5-hydroxymethylfurfural, it also accelerates the non-Radida reactions of 5-hydroxymethylfurfural, including the base-catalyzed 5-hydroxymethylfurfural Cannizaro reaction and the 5-hydroxymethylfurfural condensation. High concentrations of base are the key reason for these non-Radida reactions. Although the product of the 5-hydroxymethylfurfural Cannizaro reaction can be electro-oxidized to 2,5-furandicarboxylic acid, the humin produced by the 5-hydroxymethylfurfural condensation cannot be converted to 2,5-furandicarboxylic acid, which leads to a decrease in carbon balance and a reduction in the yield of 2,5-furandicarboxylic acid. Studies have found that although 5-hydroxymethylfurfural (5-HMF) exhibits good stability in a neutral environment, its oxidation in this environment suffers from drawbacks such as low current density, incomplete oxidation, and slow reaction rate. This limits the concentration of 5-HMF and prevents the preparation of high-concentration 2,5-furandicarboxylic acid solutions, leading to higher separation costs. Therefore, developing an electrolyzer structure that can inhibit the Cannizaro reaction and condensation reaction of 5-HMF in an alkaline environment is crucial. Summary of the Invention

[0004] The present invention is proposed to overcome the shortcomings of the prior art, and its purpose is to provide an anode plate for a reactor used for the selective oxidation of high concentration of 5-hydroxymethylfurfural to prepare 2,5-furandicarboxylic acid by electrocatalysis.

[0005] This invention is achieved through the following technical solution:

[0006] An anode plate for a reactor used for electrocatalytic high-concentration 5-hydroxymethylfurfural includes a heart-shaped static mixing structure and a flow channel field on one end face and an integrated cooling chamber structure on the other end face. The lower side of the anode plate has a No. 1 and a No. 2 inlet, and the upper side has an outlet. The flow channel field is a multi-channel serpentine flow channel field. The heart-shaped static mixing structure includes multiple spaced heart-shaped mixing tanks connected by transition tanks. The integrated cooling chamber structure includes a cooling tank and multiple flow channel ridges arranged within the cooling tank, with the multiple flow channel ridges staggered.

[0007] In the above technical solution, the anode plate has multiple connection holes along its edge for assembly and connection with other components of the reactor.

[0008] In the above technical solution, the anode plate is made of any one of carbon, iron, cobalt, nickel, molybdenum or tungsten.

[0009] In the above technical solution, the anode plate is made of at least one of carbon, aluminum, iron, cobalt, nickel, molybdenum and tungsten, and at least one of sulfur, phosphorus, oxygen, nitrogen and silicon.

[0010] In the above technical solution, the multi-channel serpentine flow field is a square structure composed of multiple serpentine flow channel grooves; the multiple flow channel grooves are parallel to each other.

[0011] In the above technical solution, the axis of the heart-shaped mixing tank is parallel to the liquid flow direction of the anode plate inlet; one end of the transition tank is connected to the tip of the front heart-shaped mixing tank, and the other end is connected to the concave part of the rear heart-shaped mixing tank.

[0012] In the above technical solution, a flow-restricting block is provided inside the apex of the heart-shaped mixing tank. The flow-restricting block is triangular, and one corner of the triangle faces the apex of the heart-shaped mixing tank.

[0013] In the above technical solution, the inlet side of the heart-shaped static mixing structure is connected to the liquid inlet tank through a transition groove, and the outlet side is connected to the inlet of the flow channel field through a connecting groove; the axis of the liquid inlet tank is perpendicular to the axis of the transition groove; the liquid inlet of plate I and the liquid inlet of plate II are both connected to the liquid inlet tank; the liquid outlet of the plate is connected to the outlet of the flow channel field.

[0014] In the above technical solution, one end of the flow channel ridge is fixedly connected to the wall of the cooling tank, and a serpentine flow channel is formed inside the cooling tank; the lower end of the cooling tank is provided with an inlet, and the upper end is provided with an outlet, and the inlet and outlet are arranged diagonally.

[0015] In the above technical solution, the area of ​​the cooling tank covers the area where the heart-shaped static mixing structure and the flow channel are located.

[0016] The beneficial effects of this invention are as follows: This invention provides an anode plate for a reactor used in the selective electrocatalytic oxidation of high-concentration 5-hydroxymethylfurfural to prepare 2,5-furandicarboxylic acid. The anode plate is designed with a unique heart-shaped static mixing structure and an integrated cooling chamber. The heart-shaped static mixing structure allows the 5-hydroxymethylfurfural aqueous solution and the alkali solution to be fully mixed in situ before entering the anode flow channel. Simultaneously, the integrated cooling chamber removes the heat generated by the mixing of the high-concentration 5-hydroxymethylfurfural solution and the alkali solution, ensuring thorough mixing of the high-concentration 5-hydroxymethylfurfural and the alkali solution. The low temperature also inhibits the reaction. During the reaction in the anode region, heat exchange occurs between the anode flow channel and the integrated cooling chamber, maintaining a constant low temperature for the anode electrolyte. This minimizes the Cannizaro reaction and suppresses the condensation reaction rate of 5-hydroxymethylfurfural, allowing for sufficient electrocatalytic oxidation of 5-hydroxymethylfurfural in a single-pass electrolysis to obtain a high-concentration 2,5-furandicarboxylic acid solution. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the flow channel from the field side view of the present invention;

[0018] Figure 2 This is a schematic diagram of the central-shaped static hybrid structure of the present invention;

[0019] Figure 3 This is a schematic diagram of the integrated cooling cavity of the present invention from a side view.

[0020] Figure 4 This study analyzes the selectivity of 2,5-furandicarboxylic acid prepared by oxidizing 5-hydroxymethylfurfural using an electrolytic cell with the anode plate of Example 1 of this invention over time.

[0021] The components are: 1. Anode plate; 2. Inlet of plate I; 3. Inlet of plate II; 4. Outlet of plate; 5. Connecting hole; 6. Flow channel; 7. Connecting groove; 8. Inlet groove; 9. Heart-shaped mixing groove; 10. Transition groove; 11. Flow resistance block; 12. Cooling groove; 13. Flow channel ridge.

[0022] For those skilled in the art, other related figures can be obtained from the above figures without any creative effort. Detailed Implementation

[0023] To enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0024] like Figures 1-3As shown, an anode plate for a reactor used for electrocatalytic high-concentration 5-hydroxymethylfurfural is provided. One end face of the anode plate 1 is provided with a heart-shaped static mixing structure and a flow channel field 6, and the other end face is provided with an integrated cooling chamber structure.

[0025] The anode plate 1 has multiple connection holes 5 formed along its edge for assembly and connection with other components of the reactor;

[0026] The anode plate 1 is made of any one of carbon, iron, cobalt, nickel, molybdenum or tungsten;

[0027] The anode plate 1 is made of at least one of carbon, aluminum, iron, cobalt, nickel, molybdenum and tungsten, and at least one of sulfur, phosphorus, oxygen, nitrogen and silicon.

[0028] The lower side of the anode plate 1 is provided with a No. I plate liquid inlet 2 and a No. II plate liquid inlet 3, and the upper side of the anode plate 1 is provided with a plate liquid outlet 4.

[0029] The flow channel field 6 is a multi-channel serpentine flow channel field, which is a square structure composed of multiple serpentine flow channel grooves; the multiple flow channel grooves are parallel to each other;

[0030] The heart-shaped static mixing structure includes multiple spaced heart-shaped mixing tanks 9, with adjacent heart-shaped mixing tanks 9 connected by transition tanks 10. The axis of the heart-shaped mixing tank 9 is parallel to the liquid flow direction at the inlet of the anode plate 1. One end of the transition tank 10 is connected to the tip of the front heart-shaped mixing tank 9, and the other end is connected to the concave part of the rear heart-shaped mixing tank 9. A flow-obstructing block 11 is provided inside the tip of the heart-shaped mixing tank 9. The flow-obstructing block 11 is triangular, and one corner of the triangle faces the tip of the heart-shaped mixing tank 9.

[0031] The inlet side of the heart-shaped static mixing structure is connected to the liquid inlet tank 8 through the transition groove 10, and the outlet side is connected to the inlet of the flow channel field 6 through the connecting groove 7; the axis of the liquid inlet tank 8 is perpendicular to the axis of the transition groove 10.

[0032] Both the No. I electrode inlet 2 and the No. II electrode inlet 3 are connected to the liquid inlet tank 8; the electrode outlet 4 is connected to the outlet of the flow channel field 6.

[0033] The length of the heart-shaped mixing tank 9 is 1 mm to 50 mm; the total length of the heart-shaped static mixing structure is 1 mm to 1000 mm.

[0034] The integrated cooling chamber structure includes a cooling tank 12 and multiple flow channel ridges 13 disposed within the cooling tank 12. One end of each flow channel ridge 13 is fixedly connected to the tank wall of the cooling tank 12. The multiple flow channel ridges 13 are staggered, forming a serpentine flow channel inside the cooling tank 12. The lower end of the cooling tank 12 is provided with a liquid inlet, and the upper end is provided with a liquid outlet, with the liquid inlet and the liquid outlet arranged diagonally.

[0035] The area of ​​the cooling tank 12 covers the area where the heart-shaped static mixing structure and the flow channel field 6 are located;

[0036] The depth of the cooling tank 12 is 0.1 mm to 20 mm, and the height of the cooling tank 12 is 10 mm to 1000 mm.

[0037] The shortest distance from the bottom of the cooling tank to the bottom of the flow channel 6 is 0.1 mm-10 mm, that is, the thickness of the electrode plate between the integrated cooling chamber structure and the flow channel 6 is 0.1 mm-10 mm.

[0038] The ridge height of the flow channel ridge 13 is 0.1 mm to 20 mm, the width is 0.1 mm to 20 mm, and the number of flow channel ridges 13 is 1 to 100.

[0039] The applicable concentration range of 5-hydroxymethylfurfural solution for the reactor containing the electrocatalytic high-concentration 5-hydroxymethylfurfural of the present invention is 0.01 mol / L to 15 mol / L, and the concentration range of alkaline solution is 0.01 mol / L to 15 mol / L.

[0040] The principle of this invention:

[0041] The heart-shaped static mixing structure of this invention is located before the anode inlet and includes several heart-shaped static mixing units continuously distributed along the axis. Alkali solution and high-concentration 5-hydroxymethylfurfural solution are introduced into the inlet tank 8 from inlet 2 of electrode plate I and inlet 3 of electrode plate II, respectively, and then enter the heart-shaped static mixing structure. After being diverted and mixed through several heart-shaped mixing tanks 9 and transition tanks 10, a uniform high-concentration 5-hydroxymethylfurfural alkaline solution is obtained at the outlet of the heart-shaped static mixing structure. The heart-shaped mixing tanks 9 of the heart-shaped static mixing structure are diversion modules, and the transition tanks 10 are mixing... The integrated module has an equal width of internal flow channels, which can effectively divide, transport, and remix the liquid. The high-concentration 5-hydroxymethylfurfural alkaline solution with uniform concentration flows out of the heart-shaped static mixing structure and passes through the flow channel field 6 of the anode plate for electrolysis. The heat generated during electrolysis exchanges heat with the coolant introduced into the integrated cooling chamber. The integrated cooling chamber forms a serpentine flow channel structure in the cooling tank, which allows the coolant to fully flow through all parts of the cooling chamber after entering through the inlet, and finally flow out from the outlet, so that the anode plate maintains a constant temperature during electrolysis.

[0042] Application Example 1

[0043] The selective electrocatalytic oxidation of high-concentration 5-hydroxymethylfurfural to prepare 2,5-furandicarboxylic acid was carried out in a reactor with the anode plate described in Example 1. The specific steps are as follows:

[0044] (I) Add 5.7 mol / L potassium hydroxide solution and 4.2 mol / L 5-hydroxymethylfurfural solution to two 25 L storage tanks respectively, and store them at a constant temperature of 2 °C in a low-temperature constant-temperature cooling device;

[0045] (II) Introduce coolant into the integrated cooling chamber at a flow rate of 100 mL / min;

[0046] (III) Potassium hydroxide solution was introduced into the heart-shaped static mixing structure at a rate of 6 mL / min and 5-hydroxymethylfurfural solution was introduced at a rate of 3 mL / min using a horizontal flow pump.

[0047] (IV) The mixed electrolyte flows through the anode plate channel and a constant current of 40 A is applied to the electrolytic cell for electrolysis. The flow rate of the coolant in the integrated cooling chamber is kept constant. The liquid is collected at the outlet and separated into 2,5-furandicarboxylic acid by acidification filtration with a selectivity of 95.3%.

[0048] The selectivity of the electrocatalytic oxidation of high-concentration 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid as a function of time is shown in the following results. Figure 4 As shown.

[0049] This invention relates to a reactor for the selective electrocatalytic oxidation of high-concentration 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid. The anode plate features a unique heart-shaped static mixing structure in front of the flow channel, while an integrated cooling chamber structure is located on the other side. The heart-shaped static mixing structure enables efficient in-situ mixing and rapid electro-oxidation of the 5-hydroxymethylfurfural solution and alkaline electrolyte in the electrolyzer, shortening the time for chemical side reactions. The integrated cooling chamber structure promotes efficient heat transfer during electrolysis, slowing down the rate of chemical side reactions. The synergistic effect of these two structures enables the selective oxidation of high-concentration 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid, which is beneficial for improving product yield and reducing energy consumption and cost in downstream product separation. Compared to the low selectivity of previously reported premixed and cyclic electrolysis modes, the anode plate structure of this application enables continuous selective electrosynthesis of 2,5-furandicarboxylic acid.

[0050] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0051] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0052] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. The applicant declares that the above description is merely a specific embodiment of this invention, but the scope of protection of this invention is not limited thereto. Those skilled in the art should understand that any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this invention fall within the scope of protection and disclosure of this invention.

Claims

1. An anode plate for a reactor for electrocatalytic high concentration 5-hydroxymethylfurfural, characterized by: One end face of the anode plate (1) is provided with a heart-shaped static mixing structure and a flow channel field (6), and the other end face is provided with an integrated cooling cavity structure; the lower part of the side face of the anode plate (1) is provided with a No. 1 plate liquid inlet (2) and a No. 2 plate liquid inlet (3), and the upper part of the side face of the anode plate (1) is provided with a plate liquid outlet (4); the flow channel field (6) is a multi-channel serpentine flow channel field; the heart-shaped static mixing structure comprises a plurality of heart-shaped mixing grooves (9) arranged at intervals, and adjacent heart-shaped mixing grooves (9) are connected through transition grooves (10); the integrated cooling cavity structure comprises a cooling groove (12) and a plurality of flow channel ridges (13) arranged in the cooling groove (12), and the plurality of flow channel ridges (13) are arranged alternately; the area of the cooling groove (12) covers the area where the heart-shaped static mixing structure and the flow channel field (6) are located.

2. The anode plate for the reactor for electrocatalysis of high concentrations of 5-hydroxymethylfurfural according to claim 1, characterized by the fact that: The anode plate (1) is formed along the edge to form a plurality of connecting holes (5) for assembly and connection with other parts of the reactor.

3. The anode plate for the reactor for electrocatalysis of high concentrations of 5-hydroxymethylfurfural according to claim 1, characterized by the fact that: The material of the anode plate (1) is any one of carbon, iron, cobalt, nickel, molybdenum or tungsten.

4. The anode plate for the reactor for electrocatalysis of high concentrations of 5-hydroxymethylfurfural according to claim 1, characterized by the fact that: The material of the anode plate (1) is a material formed by at least one of carbon, aluminum, iron, cobalt, nickel, molybdenum and tungsten and at least one of sulfur, phosphorus, oxygen, nitrogen and silicon.

5. The anode plate for the reactor for electrocatalysis of high concentrations of 5-hydroxymethylfurfural according to claim 1, characterized by the fact that: The multi-channel serpentine flow channel field is a square structure composed of a plurality of serpentine coiled flow channel grooves; the plurality of flow channel grooves are parallel to each other.

6. The anode plate for the reactor for electrocatalysis of high concentrations of 5-hydroxymethylfurfural according to claim 1, characterized by the fact that: The axis of the heart-shaped mixing groove (9) is parallel to the liquid flow direction of the anode plate (1) liquid inlet; one end of the transition groove (10) is connected to the heart apex of the front side heart-shaped mixing groove (9), and the other end is connected to the heart recess of the rear side heart-shaped mixing groove (9).

7. The anode plate for the reactor for electrocatalysis of high concentrations of 5-hydroxymethylfurfural according to claim 1, characterized by the fact that: The heart apex of the heart-shaped mixing groove (9) is internally provided with a flow resistance block (11), which is a triangle, and one corner of the triangle is directly opposite the heart apex of the heart-shaped mixing groove (9).

8. The anode plate for the reactor for electrocatalysis of high concentrations of 5-hydroxymethylfurfural according to claim 1, characterized by the fact that: The inlet side of the heart-shaped static mixing structure is communicated with the liquid inlet groove (8) through the transition groove (10), and the outlet side is communicated with the inlet of the flow channel field (6) through the connecting groove (7); the axis of the liquid inlet groove (8) is perpendicular to the axis of the transition groove (10); the No. 1 plate liquid inlet (2) and the No. 2 plate liquid inlet (3) are both communicated with the liquid inlet groove (8); and the plate liquid outlet (4) is communicated with the outlet of the flow channel field (6).

9. The anode plate for the reactor for electrocatalysis of high concentrations of 5-hydroxymethylfurfural according to claim 1, characterized by the fact that: One end of the flow channel ridge (13) is fixedly connected with the groove wall of the cooling groove (12), and a serpentine flow channel is formed in the cooling groove (12); the lower end of the cooling groove (12) is provided with a liquid inlet, and the upper end is provided with a liquid outlet, and the liquid inlet and the liquid outlet are diagonally arranged.

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