Anode plate of reactor for electrocatalysis of high-concentration 5-hydroxymethylfurfural

Abstract

The invention discloses an anode plate of a reactor for electro-catalysis of high-concentration 5-hydroxymethylfurfural. A heart-shaped static mixing structure and a flow channel field are arranged on the end face of one end of the anode plate, and an integrated cooling cavity structure is arranged on the end face of the other end of the anode plate; the flow channel field is a multi-channel snakelike flow channel field; the heart-shaped static mixing structure comprises a plurality of heart-shaped mixing grooves which are arranged at intervals, and the adjacent heart-shaped mixing grooves are connected through transition grooves; the integrated cooling cavity structure comprises a cooling groove and a plurality of runner ridges arranged in the cooling groove, and the runner ridges are arranged in a staggered mode. According to the heart-shaped static mixing structure, in-situ efficient mixing and rapid electrooxidation of the 5-hydroxymethylfurfural solution and the alkaline electrolyte in the electrolytic cell are achieved, and the time of chemical side reaction is shortened; the integrated cooling cavity structure promotes efficient transfer of heat in the electrolysis process and slows down the rate of chemical side reactions; the two synergistically realize selective oxidation of high-concentration 5-hydroxymethylfurfural to prepare 2, 5-furandicarboxylic acid, and the product yield is improved.

Description

Technical Field

[0001] The invention belongs to the field of biomass catalytic conversion and chemical engineering, and particularly relates to an anode plate of a reactor for electrocatalyzing high-concentration 5-hydroxymethylfurfural. Background Art

[0002] The oxidation and upgrading of 5-hydroxymethylfurfural into high-value industrial raw materials will help the current transformation from traditional petrochemical industry to green renewable resources. 2,5-Furandicarboxylic acid is a biomass green chemical platform molecule produced by the oxidation of 5-hydroxymethylfurfural, which is expected to replace terephthalic acid and become the basic raw material for the synthesis of polyethylene 2,5-furandicarboxylate.

[0003] The non-Faradaic side reactions of 5-HMF in alkaline solution are a key challenge for the large-scale production of 2,5-furandicarboxylic acid. Although increasing the concentration of 5-HMF and base can increase the current density of 5-HMF oxidation, it also accelerates the non-Faradaic reactions of 5-HMF, including the base-catalyzed Cannizzaro reaction of 5-HMF and the condensation of 5-HMF. High concentration of base is the key reason for these non-Faradaic reactions.

[0004] Although the product of 5-hydroxymethylfurfural after the Cannizzaro reaction can also be electro-oxidized to finally generate 2,5-furandicarboxylic acid, the humin produced by the condensation of 5-hydroxymethylfurfural cannot be converted into 2,5-furandicarboxylic acid, which will lead to a decrease in carbon balance and a decrease in the yield of 2,5-furandicarboxylic acid. Studies have found that although 5-hydroxymethylfurfural shows good stability in a neutral environment, the oxidation of 5-hydroxymethylfurfural in a neutral environment has the disadvantages of low current density, incomplete oxidation, and slow reaction rate, which leads to the limitation of 5-hydroxymethylfurfural concentration and the inability to prepare a high concentration 2,5-furandicarboxylic acid solution, which will lead to a higher separation cost. Therefore, it is crucial to develop an electrolytic cell structure that can inhibit the Cannizzaro reaction and condensation reaction of 5-hydroxymethylfurfural in an alkaline environment. Summary of the invention

[0005] The present invention is proposed to overcome the shortcomings of the prior art and aims to provide an anode plate of a reactor for preparing 2,5-furandicarboxylic acid by electrocatalytic selective oxidation of high-concentration 5-hydroxymethylfurfural.

[0006] The present invention is achieved through the following technical solutions:

[0007] An anode plate of a reactor for electrocatalytic high-concentration 5-hydroxymethylfurfural, wherein a heart-shaped static mixing structure and a flow channel field are arranged on one end face of the anode plate, and an integrated cooling cavity structure is arranged on the other end face; a No. I plate liquid inlet and a No. II plate liquid inlet are arranged on the lower part of the side surface of the anode plate, and a plate liquid outlet is arranged on the upper part of the side surface of the anode plate; the flow channel field is a multi-channel serpentine flow channel field; the heart-shaped static mixing structure includes a plurality of heart-shaped mixing grooves arranged at intervals, and adjacent heart-shaped mixing grooves are connected by transition grooves; the integrated cooling cavity structure includes a cooling groove and a plurality of flow channel ridges arranged in the cooling groove, and the plurality of flow channel ridges are arranged in a staggered manner.

[0008] In the above technical solution, a plurality of connection holes are formed along the edge of the anode plate for assembly and connection with other components of the reactor.

[0009] In the above technical solution, the material of the anode plate is any one of carbon, iron, cobalt, nickel, molybdenum or tungsten.

[0010] In the above technical solution, the material of the anode plate is an alloy 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.

[0011] In the above technical solution, the multi-channel serpentine flow field is a square structure composed of a plurality of serpentine-shaped flow channels; the plurality of flow channels are parallel to each other.

[0012] In the above technical solution, the axis of the heart-shaped mixing tank is parallel to the liquid flow direction of the anode plate liquid inlet; one end of the transition tank is connected to the apex of the front heart-shaped mixing tank, and the other end is connected to the concave part of the rear heart-shaped mixing tank.

[0013] In the above technical solution, a flow resistance block is arranged inside the apex of the heart-shaped mixing tank. The flow resistance block is triangular, and one corner of the triangle faces the apex of the heart-shaped mixing tank.

[0014] 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 tank, and the outlet side is connected to the inlet of the flow field through a connecting tank; the axis of the liquid inlet tank and the axial direction of the transition tank are perpendicular to each other; the liquid inlet of the No. 1 electrode plate and the liquid inlet of the No. 2 electrode plate are both connected to the liquid inlet tank; the liquid outlet of the electrode plate is connected to the outlet of the flow field.

[0015] In the above technical solution, one end of the flow channel ridge is fixedly connected to the groove wall of the cooling groove, and a serpentine flow channel is formed inside the cooling groove; a liquid inlet is set at the lower end of the cooling groove, and a liquid outlet is set at the upper end, and the liquid inlet and the liquid outlet are set diagonally.

[0016] In the above technical solution, the area of ​​the cooling groove covers the area where the heart-shaped static mixing structure and the flow channel are located.

[0017] The beneficial effects of the present invention are:

[0018] The invention provides an anode plate of a reactor for preparing 2,5-furandicarboxylic acid by electrocatalytic high-concentration 5-hydroxymethylfurfural selective oxidation. The anode plate is designed with a unique heart-shaped static mixing structure and an integrated cooling chamber. Through the heart-shaped static mixing structure, a 5-hydroxymethylfurfural aqueous solution and an alkaline solution are fully mixed in situ before entering an anode flow channel. Meanwhile, the heat generated by the mixing of the high-concentration 5-hydroxymethylfurfural solution and the alkaline solution is taken away through the integrated cooling chamber, so that the high-concentration 5-hydroxymethylfurfural and the alkaline solution are fully mixed. Meanwhile, the reaction thereof is suppressed by low temperature. When the reaction occurs in the anode region, heat is exchanged between the anode flow channel and the integrated cooling chamber, so that the anode electrolyte always maintains a constant low temperature, the Cannizzaro reaction is reduced as much as possible, the condensation reaction rate of 5-hydroxymethylfurfural is suppressed, and the 5-hydroxymethylfurfural is fully electrocatalytically oxidized as much as possible in a single-pass electrolysis to obtain a high-concentration 2,5-furandicarboxylic acid solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic structural diagram of the flow field of the present invention from a side perspective;

[0020] Figure 2 It is a structural schematic diagram of the central static mixing structure of the present invention;

[0021] Figure 3 It is a schematic structural diagram of the integrated cooling cavity of the present invention from a side perspective.

[0022] Figure 4 The selectivity of 2,5-furandicarboxylic acid prepared by oxidizing 5-hydroxymethylfurfural using an electrolytic cell having an anode plate according to Example 1 of the present invention varies with time.

[0023] in:

[0024] 1. Anode plate; 2. Liquid inlet of plate No. Ⅰ; 3. Liquid inlet of plate No. Ⅱ; 4. Liquid outlet of plate; 5. Connection hole; 6. Flow channel; 7. Connection groove; 8. Liquid inlet groove; 9. Heart-shaped mixing groove; 10. Transition groove; 11. Flow resistance block; 12. Cooling groove; 13. Flow channel ridge;

[0025] For ordinary technicians in this field, other relevant drawings can be obtained based on the above drawings without any creative work. DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0027] like Figures 1 to 3As shown, an anode plate of a reactor for electrocatalysis of high-concentration 5-hydroxymethylfurfural, wherein one end surface of the anode plate 1 is provided with a heart-shaped static mixing structure and a flow channel field 6, and the other end surface is provided with an integrated cooling cavity structure;

[0028] The anode plate 1 is formed with a plurality of connection holes 5 along the edge for assembly and connection with other parts of the reactor;

[0029] The material of the anode plate 1 is any one of carbon, iron, cobalt, nickel, molybdenum or tungsten;

[0030] The material of the anode plate 1 is an alloy 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;

[0031] The lower part of the 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 part of the side of the anode plate 1 is provided with a plate liquid outlet 4;

[0032] The flow channel field 6 is a multi-channel serpentine flow channel field, which is a square structure composed of a plurality of serpentine-shaped flow channel grooves; the plurality of flow channel grooves are parallel to each other;

[0033] 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 by transition grooves 10, and the axis of the heart-shaped mixing groove 9 is parallel to the liquid flow direction of the liquid inlet of the anode plate 1; one end of the transition groove 10 is connected to the apex of the front heart-shaped mixing groove 9, and the other end is connected to the concave of the rear heart-shaped mixing groove 9; a flow resistance block 11 is arranged inside the apex of the heart-shaped mixing groove 9, and the flow resistance block 11 is triangular, and one corner of the triangle is facing the apex of the heart-shaped mixing groove 9;

[0034] The inlet side of the heart-shaped static mixing structure is connected to the liquid inlet tank 8 through the transition tank 10, and the outlet side is connected to the inlet of the flow field 6 through the connecting tank 7; the axis of the liquid inlet tank 8 and the axial direction of the transition tank 10 are perpendicular to each other;

[0035] The liquid inlet 2 of the No. Ⅰ plate and the liquid inlet 3 of the No. Ⅱ plate are both connected to the liquid inlet tank 8; the liquid outlet 4 of the plate is connected to the outlet of the flow channel field 6;

[0036] The length of the heart-shaped mixing groove 9 is 1mm-50mm; the total length of the heart-shaped static mixing structure is 1mm-1000mm;

[0037] The integrated cooling cavity structure includes a cooling groove 12 and a plurality of flow channel ridges 13 arranged in the cooling groove 12, one end of the flow channel ridge 13 is fixedly connected to the groove wall of the cooling groove 12, and the plurality of flow channel ridges 13 are staggered to form a serpentine flow channel inside the cooling groove 12; a liquid inlet is arranged at the lower end of the cooling groove 12, and a liquid outlet is arranged at the upper end, and the liquid inlet and the liquid outlet are arranged diagonally;

[0038] 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;

[0039] The depth of the cooling groove 12 is 0.1 mm to 20 mm, and the height of the cooling groove 12 is 10 mm to 1000 mm;

[0040] The shortest distance from the bottom of the cooling groove to the bottom of the flow channel groove of the flow channel field 6 is 0.1mm-10mm, that is, the thickness of the electrode plate between the integrated cooling cavity structure and the flow channel field 6 is 0.1mm-10mm;

[0041] The flow channel ridge 13 has a ridge height of 0.1 mm to 20 mm, a width of 0.1 mm to 20 mm, and a number of the flow channel ridges 13 of 1 to 100;

[0042] The applicable 5-hydroxymethylfurfural solution concentration range of the reactor loaded with the electrocatalytic high-concentration 5-hydroxymethylfurfural of the present invention is 0.01 mol / L-15 mol / L, and the alkali solution concentration range is 0.01 mol / L-15 mol / L.

[0043] Principle of the present invention:

[0044] The heart-shaped static mixing structure of the present invention is arranged in front of the anode liquid inlet, and comprises a plurality of heart-shaped static mixing units continuously distributed along the axis. The alkali solution and the high-concentration 5-hydroxymethylfurfural solution are respectively introduced into the liquid inlet tank 8 from the No. Ⅰ plate liquid inlet 2 and the No. Ⅱ plate liquid inlet 3, and then enter the heart-shaped static mixing structure, and are divided and mixed through a plurality of heart-shaped mixing tanks 9 and transition tanks 10. A high-concentration 5-hydroxymethylfurfural alkali solution with uniform concentration is obtained at the outlet of the heart-shaped static mixing structure. The heart-shaped mixing tank 9 of the heart-shaped static mixing structure is a flow dividing module, and the transition tank 10 is a mixing The module has an internal flow channel width that is equal everywhere, which can well perform liquid diversion, liquid transmission, and remixing; the high-concentration 5-hydroxymethylfurfural alkaline solution with uniform concentration flowing out of the heart-shaped static mixing structure flows through the anode plate flow channel field 6 for electrolysis; the heat generated during the electrolysis process exchanges heat with the coolant introduced into the integrated cooling cavity, and a serpentine flow channel structure is formed in the cooling groove of the integrated cooling cavity, so that the coolant enters the cooling cavity through the liquid inlet and fully flows through various parts of the cooling cavity, and finally flows out from the liquid outlet, so that the anode plate maintains a constant temperature during the electrolysis process.

[0045] Application Example 1

[0046] A reactor having the anode plate described in Example 1 is used to electrocatalyze high-concentration 5-hydroxymethylfurfural selective oxidation to prepare 2,5-furandicarboxylic acid, and the specific steps are as follows:

[0047] (I) Add 5.7 mol / L potassium hydroxide solution and 4.2 mol / L 5-hydroxymethylfurfural solution into two 25 L liquid storage tanks respectively, and place them in a low temperature constant temperature cooling device to keep them at a constant temperature of 2°C;

[0048] (II) introducing a cooling liquid at a flow rate of 100 mL / min into the integrated cooling chamber;

[0049] (III) introducing potassium hydroxide solution at a rate of 6 mL / min and 5-hydroxymethylfurfural solution at a rate of 3 mL / min into the heart-shaped static mixing structure using a horizontal flow pump for mixing;

[0050] (IV) The mixed electrolyte flows through the anode plate flow channel, and a constant current of 40A is applied to the electrolytic cell for electrolysis, and the flow rate of the coolant in the integrated cooling chamber is kept constant. The feed liquid is collected at the outlet, and 2,5-furandicarboxylic acid is separated by acidification filtration, with a selectivity of 95.3%.

[0051] The selectivity of electrocatalytic high concentration 5-hydroxymethylfurfural selective oxidation to produce 2,5-furandicarboxylic acid changes with time. Figure 4 shown.

[0052] The anode plate of the reactor for preparing 2,5-furandicarboxylic acid by electrocatalytic high-concentration 5-hydroxymethylfurfural selective oxidation of the present invention is provided with a unique heart-shaped static mixing structure in front of a flow channel field, and an integrated cooling cavity structure is provided on the other side; the heart-shaped static mixing structure realizes in-situ efficient mixing and rapid electrooxidation of a 5-hydroxymethylfurfural solution and an alkaline electrolyte in an electrolytic cell, shortening the time of chemical side reactions; the integrated cooling cavity structure promotes efficient heat transfer during the electrolysis process, slowing down the rate of chemical side reactions; the synergistic effect of the two realizes the selective oxidation of high-concentration 5-hydroxymethylfurfural to prepare 2,5-furandicarboxylic acid, which is beneficial to improving the product yield and reducing the energy consumption and cost of downstream product separation; compared with the low selectivity of the premixing and cyclic electrolysis modes reported by previous researchers, the anode plate structure of the present application can realize continuous selective electrosynthesis of 2,5-furandicarboxylic acid.

[0053] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0054] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0055] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0056] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. An anode plate for a reactor for electrocatalysis of high concentration 5-hydroxymethylfurfural, characterized in that: A heart-shaped static mixing structure and a flow channel field (6) are arranged on one end face of the anode plate (1), and an integrated cooling chamber structure is arranged on the other end face; a No. I plate liquid inlet (2) and a No. II plate liquid inlet (3) are arranged on the lower part of the side face of the anode plate (1), and a plate liquid outlet (4) is arranged on the upper part of the side face of the anode plate (1); 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 by transition grooves (10); the integrated cooling chamber 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 in a staggered manner.

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

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

4. The anode plate of the reactor for electrocatalysis of high concentration 5-hydroxymethylfurfural according to claim 1, characterized in that: The material of the anode plate (1) is an alloy 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 of the reactor for electrocatalysis of high concentration 5-hydroxymethylfurfural according to claim 1, characterized in that: The multi-channel serpentine flow field is a square structure composed of a plurality of serpentine-shaped flow channels; the plurality of flow channels are parallel to each other.

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

7. The anode plate of the reactor for electrocatalysis of high concentration 5-hydroxymethylfurfural according to claim 1, characterized in that: A flow resistance block (11) is arranged inside the apex of the heart-shaped mixing groove (9). The flow resistance block (11) is triangular, and one corner of the triangle faces the apex of the heart-shaped mixing groove (9).

8. The anode plate of the reactor for electrocatalysis of high concentration 5-hydroxymethylfurfural according to claim 1, characterized in that: The inlet side of the heart-shaped static mixing structure is connected to a liquid inlet groove (8) via a transition groove (10), and the outlet side is connected to an inlet of a flow channel field (6) via a connecting groove (7); the axis of the liquid inlet groove (8) and the axial direction of the transition groove (10) are perpendicular to each other; the No. 1 electrode plate liquid inlet (2) and the No. 2 electrode plate liquid inlet (3) are both connected to the liquid inlet groove (8); and the electrode plate liquid outlet (4) is connected to an outlet of the flow channel field (6).

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

10. The anode plate of a reactor for electrocatalysis of high concentration 5-hydroxymethylfurfural according to claim 1, characterized in that: 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.

Images