Graphite felt anode material and preparation method and application thereof

Abstract

The application relates to the field of electrochemistry, and specifically discloses a preparation method of a graphite felt anode material, the graphite felt anode material and application; the preparation method of the graphite felt anode material comprises the following steps: graphite felt pretreatment; graphite felt modification: blending nano transition metal particles and an adhesive according to a weight ratio (2.4-5.2):1 to obtain a modifier; immersing and treating the graphite felt in the modifier, washing and drying after solidification, and obtaining the graphite felt anode material; wherein the adhesive comprises the following components: a hydroxyl acrylic acid resin, an anthraquinone substance, an amino-terminated polyaniline and a solvent; the graphite felt anode material prepared by the application can have a long electrode service life and improve the electrochemical performance of the electrode material, so that when the graphite felt anode material is applied to an electrochemical synthesis process of dimethyl sebacate, the reaction current efficiency can be improved, and the selectivity of by-products can be reduced.

Description

Technical Field

[0001] This invention belongs to the technical field of electrochemistry, specifically relating to a method for preparing graphite felt anode material, the graphite felt anode material itself, and its applications. Background Technology

[0002] Electrochemical synthesis is an important process in the chemical industry. At present, research has shown that esters such as dimethyl sebacate can be prepared by electrochemical synthesis.

[0003] In the electrochemical synthesis of dimethyl sebacate, platinum electrodes, titanium-plated platinum electrodes, titanium-based PbO2 electrodes, and titanium-based IrO2 electrodes are generally used as anode electrodes; gold electrodes, silver electrodes, and titanium-plated silver electrodes are used as cathode electrodes. The core component of electrochemical synthesis is the electrolytic cell, and the final lifespan of the electrolytic cell depends on the lifespan of the electrode materials. The electrosynthesis reaction of dimethyl sebacate takes place at the anode, and the anode material is prone to corrosion during electrolysis. Therefore, the applicant has attempted to use graphite felt as a substrate anode material in the hope of delaying electro-corrosion on the anode and increasing the service life of the anode material.

[0004] However, in actual experiments, it was found that although graphite felt as an anode material can extend the service life to a certain extent, the following problems still exist: First, the electrocatalytic performance of the anode material decreases, and the reaction current efficiency decreases; second, the selectivity of by-products increases, resulting in a higher impurity content in the target product. In light of these issues, how to both extend the electrode's service life and improve the electrochemical performance of the electrode material remains a pressing problem to be solved in the industry. Summary of the Invention

[0005] To simultaneously address the issues of short electrode life and reduced electrochemical performance, this application provides a method for preparing graphite felt anode material, the graphite felt anode material itself, and its applications.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] First, this invention provides a method for preparing a graphite felt anode material, comprising the following steps:

[0008] (1) Pretreatment of graphite felt;

[0009] (2) Graphite felt modification: Nano-transition metal particles and adhesive are mixed at a weight ratio of 2.4 to 5.2:1 to obtain a modifier; graphite felt is immersed in the modifier, cured, washed and dried to obtain graphite felt anode material.

[0010] The adhesive comprises the following components in parts by weight:

[0011] 10-30 parts of hydroxyl acrylic resin, 25-45 parts of anthraquinones, 15-30 parts of amino-terminated polyaniline, and 15-30 parts of solvent.

[0012] Pretreatment of graphite felt: The graphite felt was cut into small blocks of 2×8cm. A three-electrode system was used, with the graphite felt as the working electrode, one end of which was immersed in the electrolyte and the other end directly connected to the electrode wire clamp. The platinum wire was used as the counter electrode and the Ag / AgCl electrode was used as the reference electrode. The graphite felt immersed in the electrolyte was oxidized and pretreated at a potential of 2V for 300s using 0.5M dilute sulfuric acid solution as the electrolyte.

[0013] Furthermore, the mass ratio of anthraquinone substances to amino-terminated polyaniline in the adhesive is 1.5 to 1.6:1.

[0014] By adopting the above technical solution, when the weight ratio of anthraquinone substances to amino-terminated polyaniline is within this range, the electron transport network of the graphite felt anode material is relatively dense, which can significantly improve the electrochemical performance of the graphite felt anode material. Secondly, when within this range, the rigid benzene ring has little impact on the overall toughness of the graphite felt anode material, making it less prone to breakage and extending the service life of the graphite felt anode material.

[0015] Furthermore, the mass ratio of hydroxyl acrylic resin to amino-terminated polyaniline in the adhesive is 1 to 1.2:1.

[0016] By adopting the above technical solution, when the weight ratio of hydroxyl acrylic resin to amino-terminated polyaniline is within this range, the crosslinking density inside the graphite felt anode material is moderate, which can improve the adhesion stability of nano-transition metal particles in the graphite felt anode material, thereby improving the electrochemical performance of the graphite felt anode material. At the same time, the increased content of amino-terminated polyaniline and anthraquinone substances further reduces the difficulty of electron transfer in the graphite felt anode material, further improving the electrochemical performance of the graphite felt anode material.

[0017] Further, the anthraquinone substance is one or more selected from emodin, aloe-emodin, and hydroxyalizarin. More preferably, the anthraquinone substance is composed of aloe-emodin and hydroxyalizarin.

[0018] By adopting the above technical solution, the selection of anthraquinone substances includes emodin-type anthraquinone compounds and alizarin-type anthraquinone compounds. Among them, emodin, aloe-emodin, and hydroxyalizarin have high hydroxyl content, and their synergistic effect with amino-terminated polyaniline, hydroxy acrylic resin, and nano-transition metal particles is better, which can further improve the reaction current efficiency of electrochemical reaction and reduce the selectivity of by-products.

[0019] Furthermore, the amino-terminated polyaniline is a diamine-terminated aniline trimer.

[0020] By adopting the above technical solutions, the selection of amino-terminated polyaniline includes, but is not limited to, phenyl-amino-terminated aniline oligomers, diamine-terminated aniline trimers, and diamine-terminated aniline pentamers. Using diamine-terminated aniline trimers instead of traditional amino-terminated polyaniline can, on the one hand, further increase the electrochemical performance of graphite felt anode materials, and on the other hand, the rigid benzene ring has little impact on the overall toughness of graphite felt anode materials, making them less prone to breakage and extending the service life of graphite felt anode materials.

[0021] Furthermore, the hydroxyl value of the hydroxyl acrylic resin is 13-38.5 mgKOH / g.

[0022] By adopting the above technical solution, within this hydroxyl value range, hydroxyl acrylic resin can further improve the electrochemical performance of graphite felt anode material, and at the same time improve the overall mechanical properties of graphite felt anode material, making it less prone to breakage and other problems.

[0023] Furthermore, in step (2), the nano-transition metal particles are Pd and / or Pt, with a particle size of 2 to 4 nm.

[0024] Further, in step (2), in the graphite felt modification step, the pretreated graphite felt is completely immersed in the modifier, ultrasonically mixed, with an ultrasonic frequency of 10-25 kHz and an ultrasonic time of 15-30 min, and taken out after immersion for 12 h.

[0025] By adopting the above technical solution, due to the small pore structure of graphite felt, ultrasonic blending allows nano-transition metal particles to fully enter the pore structure of graphite felt while maintaining stable dispersion of nano-transition metal particles, resulting in uniform and stable electron transfer performance throughout the graphite felt anode material.

[0026] By adopting the above technical solution, the graphite felt is first pretreated to expose its internal pores and active sites, so as to facilitate full contact with the modifier in the later stage and improve its surface hydrophilicity. The modifier uses nano-transition metal particles, hydroxyl acrylic resin, anthraquinone substances and amino-terminated polyaniline as the main raw materials, which have a synergistic effect on improving the dielectric and mechanical properties of the graphite felt. The specific principle is as follows:

[0027] Nano-transition metal particles can be well dispersed in the solvent under the action of hydroxyl acrylic resin, enhancing the anode material's ability to adsorb hydrogen. Simultaneously, the benzoquinone structure of anthraquinones can spontaneously react with the amine of amino-terminated polyaniline under oxidative conditions, undergoing a Michael addition reaction to first generate a monosubstituted hydroquinone intermediate, followed by an addition reaction to obtain a disubstituted quinone amine. The disubstituted quinone amine contains a large number of active imines, hydroxyl groups, and carbonyl groups. On the one hand, these active groups (especially hydroxyl and imine) have high adsorption capacity for nano-transition metal particles under hydrogen bonding, allowing for thorough dispersion of the nano-transition metal particles. On the other hand, the hydroxyl, amino, and conjugated double bonds contained in the disubstituted quinone amine can form a dense conductive network with the nano-transition metal particles and hydroxyl acrylic resin, reducing the difficulty of electron transfer in the anode material and significantly improving electrochemical performance.

[0028] Meanwhile, the cross-linking of hydroxyl acrylic resin, anthraquinone substances, and amino-terminated polyaniline enables nano-transition metal particles to be firmly fixed in the pores of graphite felt, thereby allowing the electrochemical performance of the anode material to maintain its excellent performance for a long time.

[0029] Secondly, hydroxyacrylic acid contains a large number of flexible segments, which can coordinate the rigid benzene ring segments in anthraquinone substances and amino-terminated polyaniline, so that the anode material always maintains excellent mechanical properties and the anode material has long service performance.

[0030] In addition, due to the moderate amount of nano-transition metal particles added, and the fact that the nano-transition metal particles are coated with polymers formed by hydroxyl acrylic resin, anthraquinone substances, and amino-terminated polyaniline, the electro-corrosion during the electrochemical reaction process can be effectively reduced, but the electrochemical performance of the anode material is not affected.

[0031] In summary, the anode material prepared by the method of the present invention has excellent electrochemical performance, as well as excellent mechanical properties and a long service life.

[0032] The present invention also provides a graphite felt anode material, which is prepared by the aforementioned method for preparing graphite felt anode material.

[0033] By adopting the above technical solution, the graphite felt anode material of this application has excellent electrochemical performance, and the overall mechanical properties of the graphite felt anode material are good. The graphite felt anode material is not prone to breakage and other problems, and its service life is extended.

[0034] The present invention also provides an application of graphite felt anode material, wherein the aforementioned graphite felt anode material is used as the anode electrode in the electrochemical synthesis process of dimethyl sebacate.

[0035] By adopting the above technical solution, this application uses a novel anode material to replace the original metal anode electrodes such as Pd and Pt, which has the following advantages: First, the graphite felt anode material has excellent electrochemical performance and can improve the current efficiency of the synthesis reaction of dimethyl sebacate; Second, due to the moderate addition of nano-transition metal particles, and the fact that the nano-transition metal particles are coated with polymers formed by hydroxyl acrylic resin, anthraquinone substances, and amino-terminated polyaniline, the electro-corrosion during the electrochemical reaction process can be effectively reduced without affecting the electrochemical performance of the anode material; Third, the anode material always maintains excellent mechanical properties, and the performance of the anode material is long-lasting.

[0036] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0037] This application modifies graphite felt using nano-transition metal particles, hydroxyl acrylic resin, anthraquinones, and amino-terminated polyaniline as modifiers to obtain a novel anode material. The graphite felt anode material exhibits excellent electrochemical performance, enhancing the current efficiency of the synthesis reaction of dimethyl sebacate. Furthermore, the nano-transition metal particles are coated with a polymer formed by hydroxyl acrylic resin, anthraquinones, and amino-terminated polyaniline, effectively reducing electro-corrosion during the electrochemical reaction process without affecting the electrochemical performance of the anode material. Moreover, the anode material maintains excellent mechanical properties throughout its lifespan. Attached Figure Description

[0038] Figure 1 The image shows a field emission scanning electron microscope (SEM) image of the graphite felt anode material prepared in Example 1, magnified 8000 times.

[0039] Figure 2 The image shows the gas chromatogram of the electrolytic reaction liquid in Example 14. Detailed Implementation

[0040] The present invention will be further illustrated below with reference to the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are for illustrative purposes only and are not intended to limit the scope of the invention.

[0041] Unless otherwise specified, the sources of raw materials for the preparation examples, embodiments, and comparative examples in this application are as follows:

[0042] Hydroxy acrylic resin:

[0043] Brand: AU-7003, hydroxyl value 82.0-88.0 mgKOH / g;

[0044] Brand: AU-7005, hydroxyl value 32.5-38.5 mg KOH / g;

[0045] Brand: ZHP-1234, hydroxyl value 13.0-19.0 mgKOH / g;

[0046] Brand: ZHP-1626, hydroxyl value 7.0-12.0 mgKOH / g;

[0047] Nanoscale transition metal particles:

[0048] Model: Pt PVP, particle size 2nm, precious metal concentration 4wt%;

[0049] Model: Pd PVP, particle size 4nm, precious metal concentration 4wt%;

[0050] Model: Pt / PdPVP, particle size 2nm, precious metal concentration 4wt%;

[0051] Graphite felt: Model JYS886, sourced from Kunshan Yizhongtian New Materials Co., Ltd.

[0052] Preparation of amino-terminated polyaniline

[0053] A diamine-terminated aniline trimer was prepared according to the following steps:

[0054] 124.7 g of N-phenyl-1,4-p-phenylenediamine was stirred and mixed with 300 mL of 1 mol / L hydrochloric acid solution. 100 g of p-phenylenediamine was added to the solution and stirring was continued until all p-phenylenediamine was dissolved, forming a light brown solution.

[0055] Under ice bath conditions, 500 mL of a 1 mol / L ammonium persulfate aqueous solution was added dropwise to the system. The reaction temperature was controlled at 10 °C, and the reaction was maintained at this temperature for 8 h. After the reaction was completed, the mixture was filtered using a Büchner funnel. The filter cake was washed with water until neutral, and then placed in 500 mL of a 1 mol / L ammonia solution for doping overnight. The mixture was then filtered, washed with water until neutral, washed with ethanol, and dried to obtain the crude product of diamine-terminated aniline trimer.

[0056] The crude product was extracted with methanol and tetrahydrofuran for 12 hours using a Soxhlet extractor. The extracted liquid was then evaporated to obtain diamine-terminated aniline trimer.

[0057] A diamine-terminated aniline pentamer was prepared according to the following steps:

[0058] 92.1 g of N-phenyl-1,4-p-phenylenediamine, 50 g of succinic anhydride and 3 L of dichloromethane were mixed and stirred to produce a gray precipitate. After filtration, the precipitate was washed with diethyl ether until the filtrate was colorless. The filtered product was placed in a vacuum drying oven and dried for 12 h to obtain the intermediate.

[0059] Dissolve 100g of intermediate and 18.9g of p-phenylenediamine in 200mL of tetrahydrofuran. Add a pre-cooled mixture of 300mL of tetrahydrofuran, 250mL of distilled water and 50mL of concentrated hydrochloric acid. The temperature of the mixture is 10℃. Slowly add 20g of 1mol / L ammonium persulfate-hydrochloric acid solution to the mixture while stirring rapidly. Keep the mixture warm for 1h.

[0060] Pour the above solution into 5L of distilled water, filter, dissolve the filtered precipitate in 500mL of 1mol / L ammonia water, add hydrazine hydrate and stir to reduce overnight, then add 1mol / L hydrochloric acid to adjust the pH of the system to 2, filter, and vacuum dry the precipitate at 45℃ for 48h.

[0061] Take 50g of the vacuum-dried sample and dissolve it in 1L of tetrahydrofuran. Then slowly add it dropwise to 3L of ethanol while stirring rapidly. After the addition is complete, filter the sample and dry the precipitate under vacuum. Extract the sample with 1,2-dichloroethane and then with tetrahydrofuran in a Soxhlet extractor to obtain the diamine-terminated aniline pentamer.

[0062] Example 1

[0063] A graphite felt anode material is prepared according to the following steps:

[0064] (1) Pretreatment of graphite felt: The graphite felt was cut into small blocks of 2×8cm. A three-electrode system was adopted, with the graphite felt as the working electrode, one end of which was immersed in the electrolyte and the other end directly connected to the electrode wire clamp. The platinum wire was used as the counter electrode and the Ag / AgCl electrode was used as the reference electrode. The graphite felt immersed in the electrolyte was oxidized and pretreated at a potential of 2V for 300s with 0.5M dilute sulfuric acid solution as the electrolyte to improve its surface hydrophilicity.

[0065] (2) Modification of graphite felt:

[0066] Take 10g of hydroxyl acrylic resin ZHP-1626, 25g of emodin methyl ether, 15g of the above-prepared diamine-terminated aniline pentamer and 50g of ethanol, stir and mix the above substances to obtain an adhesive.

[0067] Take 24g of nano-transition metal particles Pt PVP and 100g of adhesive and stir and mix them at 600rpm to obtain the modifier;

[0068] The pretreated graphite felt was completely impregnated in the modifier and ultrasonically blended at a frequency of 20 kHz for 25 min. After impregnation for 12 h, the material was removed, heated to 70 °C, and held at that temperature for 5 h to achieve drying and curing. The cured graphite felt was then washed and dried in a vacuum drying oven for 2 h to obtain the graphite felt anode material. The SEM image of the graphite felt anode material prepared in Example 1, magnified 8000 times under a field emission scanning electron microscope, is shown below. Figure 1 As shown in the figure, a large number of clustered nano-transition metal particles are attached to the surface of the graphite felt anode material, which effectively increases the electrocatalytic performance of the graphite felt anode material.

[0069] Example 2

[0070] A graphite felt anode material is identical to that in Example 1, except that the mass ratio of anthraquinones and amino-terminated polyaniline is different, as detailed below:

[0071] Take 32g of emodin methyl ether and 20g of diamine-terminated aniline pentamer. The mass ratio of anthraquinone substances to amino-terminated polyaniline is 1.6:1.

[0072] Example 3

[0073] A graphite felt anode material is identical to that in Example 1, except that the mass ratio of anthraquinones and amino-terminated polyaniline is different, as detailed below:

[0074] Take 45g of emodin methyl ether and 30g of diamine-terminated aniline pentamer. The weight ratio of anthraquinone substances to amino-terminated polyaniline is 1.5:1.

[0075] Example 4

[0076] A graphite felt anode material is otherwise the same as in Example 2, except that the mass ratio of hydroxyl acrylic resin to amino-terminated polyaniline is different, as detailed below:

[0077] Take 20g of hydroxyl acrylic resin ZHP-1626, 20g of diamine-terminated aniline pentamer, and the weight ratio of anthraquinone substances to amino-terminated polyaniline is 1:1.

[0078] Example 5

[0079] A graphite felt anode material is otherwise the same as in Example 2, except that the mass ratio of hydroxyl acrylic resin to amino-terminated polyaniline is different, as detailed below:

[0080] Take 24g of hydroxyl acrylic resin ZHP-1626 and 20g of diamine-terminated aniline pentamer. The mass ratio of anthraquinone substances to amino-terminated polyaniline is 1.2:1.

[0081] Example 6

[0082] A graphite felt anode material is otherwise the same as in Example 2, except that the mass ratio of hydroxyl acrylic resin to amino-terminated polyaniline is different, as detailed below:

[0083] Take 30g of hydroxyl acrylic resin ZHP-1626 and 20g of diamine-terminated aniline pentamer. The mass ratio of anthraquinone substances to amino-terminated polyaniline is 1.5:1.

[0084] Example 7

[0085] A graphite felt anode material is the same as in Example 5, except that the anthraquinones are different in the choice of the anthraquinones. In this example, rhein is used instead of rhein methyl ether by weight.

[0086] Example 8

[0087] A graphite felt anode material is the same as in Example 7, except that the amino-terminated polyaniline is different. In this example, an equal weight of diamine-terminated aniline pentamer is used instead of diamine-terminated aniline trimer.

[0088] Example 9

[0089] A graphite felt anode material is otherwise the same as in Example 8, except that the hydroxyl value of the hydroxyl acrylic resin is different, as detailed below:

[0090] In this embodiment, hydroxyl acrylic resin of grade ZHP-1234 (hydroxyl value 13.0-19.0 mgKOH / g) is used in place of hydroxyl acrylic resin of grade ZHP-1626 (hydroxyl value 7.0-12.0 mgKOH / g).

[0091] Example 10

[0092] A graphite felt anode material is otherwise the same as in Example 8, except that the hydroxyl value of the hydroxyl acrylic resin is different, as detailed below:

[0093] In this embodiment, hydroxyl acrylic resin of grade AU-7005 (hydroxyl value 32.5-38.5 mgKOH / g) is used in place of hydroxyl acrylic resin of grade ZHP-1626 (hydroxyl value 7.0-12.0 mgKOH / g) by weight.

[0094] Example 11

[0095] A graphite felt anode material is otherwise the same as in Example 8, except that the hydroxyl value of the hydroxyl acrylic resin is different, as detailed below:

[0096] In this embodiment, hydroxyl acrylic resin of grade AU-7003 (hydroxyl value 82.0-88.0 mgKOH / g) was used in place of hydroxyl acrylic resin of grade ZHP-1626 (hydroxyl value 7.0-12.0 mgKOH / g) by weight.

[0097] Example 12

[0098] A graphite felt anode material is otherwise the same as in Example 10, except that the mass ratio of nano-transition metal particles to adhesive is different, specifically as follows: the mass ratio of nano-transition metal particles to adhesive is 3:1.

[0099] Example 13

[0100] A graphite felt anode material is otherwise the same as in Example 10, except that the mass ratio of nano-transition metal particles to adhesive is different, specifically as follows: the mass ratio of nano-transition metal particles to adhesive is 5.2:1.

[0101] Example 14

[0102] A graphite felt anode material is the same as in Example 12, except that the hydroxyl value of the hydroxyl acrylic resin is different. Specifically, in this example, Pd PVP nano-transition metal particles are used in place of Pt PVP nano-transition metal particles by the same mass.

[0103] Example 15

[0104] A graphite felt anode material is the same as in Example 12, except that the hydroxyl value of the hydroxyl acrylic resin is different. Specifically, in this example, Pt / Pd PVP nano-transition metal particles are used in place of Pt PVP nano-transition metal particles by the same mass.

[0105] Example 16

[0106] A graphite felt anode material is the same as in Example 15, except that the graphite felt is subjected to ultrasonic blending during the impregnation treatment in the modifier. The specific parameters are as follows: In this example, when the graphite felt is impregnated in the modifier, the ultrasonic frequency is controlled at 10 kHz and the ultrasonic time is 30 min.

[0107] Example 17

[0108] A graphite felt anode material is the same as in Example 15, except that the graphite felt is subjected to ultrasonic blending during the impregnation treatment in the modifier. The specific parameters are as follows: In this example, when the graphite felt is impregnated in the modifier, the ultrasonic frequency is controlled at 25 kHz and the ultrasonic time is 15 min.

[0109] Comparative Example 1

[0110] An anode material is otherwise the same as in Example 1, except that the graphite felt is pretreated according to the following steps: the graphite felt is cut into small pieces of 2×8cm, washed with clean water, and dried to obtain the anode material.

[0111] Comparative Example 2

[0112] An anode material is the same as in Example 1, except that the composition of the modifier is different, as follows: in Comparative Example 2, hydroxyl acrylic resin and other substances are used to replace anthraquinones.

[0113] Comparative Example 3

[0114] An anode material is the same as in Example 1, except that the composition of the modifier is different, as follows: in Comparative Example 3, hydroxyl acrylic resin is used in place of amino-terminated polyaniline by mass.

[0115] Comparative Example 4

[0116] An anode material is the same as in Example 1, except that the composition of the modifier is different, as follows: in Comparative Example 4, amino-terminated polyaniline is used to replace hydroxyl acrylic resin by mass.

[0117] Comparative Example 5

[0118] An anode material is the same as in Example 1, except that the composition of the modifier is different, as follows: in Comparative Example 5, an equal mass of modifier is used to replace nano-transition metal particles.

[0119] Application Examples

[0120] Application Example 1

[0121] An electrochemical process for synthesizing dimethyl sebacate is carried out according to the following steps:

[0122] After mixing 200g of monomethyl adipic acid, 200g of toluene and 300g of potassium methoxide evenly, the mixture was transferred to an electrolytic cell, and then 1.45g of ZSM-5 molecular sieve with a Ni content of 6.30wt% and a Ce content of 2.99wt% was added.

[0123] The anode of the electrolytic cell was made of graphite felt anode material prepared in Example 1, and the cathode was a gold electrode. The electrolytic cell was heated to 50°C, and electrolysis was initiated by applying current. The electrode potential of the electrolytic cell was 12.2V, and the current density was 1800A / m. 2 The electrolysis time was 10 hours. After the reaction was completed, the solid catalyst was removed by filtration, the reaction solution was separated, and the resulting crude mixture was distilled to obtain the byproduct and the product dimethyl sebacate.

[0124] Application Example 2-17 and Comparative Example 1-5

[0125] An electrochemical process for synthesizing dimethyl sebacate differs from Application Example 1 in that the raw material used at the anode of the electrolytic cell is different, as detailed below:

[0126] In Application Example 2, the anode of the electrolytic cell uses the graphite felt anode material prepared in Example 2;

[0127] In Application Example 3, the anode of the electrolytic cell uses the graphite felt anode material prepared in Example 3;

[0128] In Application Example 4, the anode of the electrolytic cell uses the graphite felt anode material prepared in Example 4;

[0129] In Application Example 5, the anode of the electrolytic cell uses the graphite felt anode material prepared in Example 5;

[0130] In Application Example 6, the anode of the electrolytic cell uses the graphite felt anode material prepared in Example 6;

[0131] In Application Example 7, the anode of the electrolytic cell uses the graphite felt anode material prepared in Example 7;

[0132] In Application Example 8, the anode of the electrolytic cell uses the graphite felt anode material prepared in Example 8;

[0133] In Application Example 9, the anode of the electrolytic cell uses the graphite felt anode material prepared in Example 9;

[0134] In Application Example 10, the anode of the electrolytic cell uses the graphite felt anode material prepared in Example 10;

[0135] In Application Example 11, the anode of the electrolytic cell uses the graphite felt anode material prepared in Example 11;

[0136] In Application Example 12, the anode of the electrolytic cell uses the graphite felt anode material prepared in Example 12;

[0137] In Application Example 13, the anode of the electrolytic cell uses the graphite felt anode material prepared in Example 13;

[0138] In Application Example 14, the anode of the electrolytic cell uses the graphite felt anode material prepared in Example 14. The gas chromatogram of the electrolytic reaction liquid is shown below. Figure 2As shown in the figure, the peak areas of the solvent, raw materials, by-products, and product dimethyl sebacate in the electrolytic reaction solution can be seen. The peak areas indicate that the graphite felt electrode prepared using this invention has excellent electrocatalytic performance, low selectivity for by-products, and a conversion rate of over 85% for the product dimethyl sebacate.

[0139] In Application Example 15, the anode of the electrolytic cell uses the graphite felt anode material prepared in Example 15;

[0140] In Application Example 16, the anode of the electrolytic cell uses the graphite felt anode material prepared in Example 16;

[0141] In Application Example 17, the anode of the electrolytic cell uses the graphite felt anode material prepared in Example 17;

[0142] In Comparative Example 1, the anode of the electrolytic cell uses the anode material prepared in Comparative Example 1;

[0143] In Comparative Example 2, the anode of the electrolytic cell uses the anode material obtained from Comparative Example 2;

[0144] In Comparative Example 3, the anode of the electrolytic cell uses the anode material prepared in Comparative Example 3;

[0145] In Comparative Example 4, the anode of the electrolytic cell uses the anode material prepared in Comparative Example 4;

[0146] In Comparative Example 5, the anode of the electrolytic cell uses the anode material obtained from Comparative Example 5.

[0147] Performance testing

[0148] I. Electrochemical Performance Testing of Graphite Felt Anode Materials

[0149] 1. Current efficiency test: The ratio of the mass of dimethyl sebacate synthesized in the electrolytic cell per unit time to the theoretical output calculated by Faraday's law; wherein, the mass of dimethyl sebacate synthesized in the electrolytic cell per unit time is obtained from the application examples.

[0150] 2. Selective detection of by-products: The ratio of the total mass of by-products synthesized in the electrolytic cell per unit time to the mass of the theoretical output calculated by Faraday's law.

[0151] The current efficiency and by-product selectivity of the graphite felt anode material are shown in Table 1.

[0152] II. Performance Testing of Graphite Felt Anode Materials

[0153] 1. Service life: By observing the application examples, the surface condition of the anode material in the electrolytic cell was observed, and the time when the surface of the anode material first showed a crack with a size ≥1cm was counted; the service life of the graphite felt anode material is shown in Table 2.

[0154] Table 1. Electrochemical performance test results of application examples 1-17 and comparative examples 1-5

[0155] Detection object Reaction current efficiency / % Byproduct selectivity / % Detection object Reaction current efficiency / % Byproduct selectivity / % Application Example 1 51.54 7.8 Application Example 12 85.75 6.3 Application Example 2 65.60 7.2 Application Example 13 83.87 6.4 Application Example 3 60.91 7.4 Application Example 14 86.69 6.3 Application Example 4 67.47 7.1 Application Example 15 88.09 6.2 Application Example 5 72.63 6.9 Application Example 16 89.97 6.2 Application Example 6 70.29 7.0 Application Example 17 90.90 6.1 Application Example 7 75.91 6.8 Application Comparative Example 1 37.49 84 Application Example 8 78.25 6.7 Application Comparative Example 2 44.05 8.1 Application Example 9 80.13 6.6 Application Comparative Example 3 43.11 8.2 Application Example 10 82.94 6.5 Application Comparative Example 4 42.17 8.2 Application Example 11 81.53 6.5 Application Comparative Example 5 39.83 8.3

[0156] Table 2. Service life test results of application examples 1-17 and comparative examples 1-5

[0157] Detection object Service life / d Detection object Service life / d Application Example 1 5.5 Application Example 12 9.2 Application Example 2 7.0 Application Example 13 9.0 Application Example 3 6.5 Application Example 14 9.3 Application Example 4 7.2 Application Example 15 9.4 Application Example 5 7.8 Application Example 16 9.6 Application Example 6 7.5 Application Example 17 9.7 Application Example 7 8.1 Application Comparative Example 1 6.5 Application Example 8 8.4 Application Comparative Example 2 6.2 Application Example 9 8.6 Application Comparative Example 3 4.2 Application Example 10 8.9 Application Comparative Example 4 4.1 Application Example 11 8.7 Application Comparative Example 5 7.1

[0158] Combining Application Example 1 and Comparative Examples 1-5 with Table 1-2, it can be seen that Comparative Example 1 uses traditional graphite felt as the anode material. Compared with Application Example 1, the reaction current efficiency of Comparative Example 1 is significantly reduced to only 37.49%, but its service life is only one day longer than that of Application Example 1. Therefore, using graphite felt alone as the anode material not only leads to a decrease in electrochemical performance during synthesis, but also does not significantly improve the electrode service life.

[0159] In Comparative Examples 2-5, the graphite felt anode materials were modified by lacking anthraquinones, amino-terminated polyaniline, hydroxyl acrylic resin, and nano-transition metal particles, respectively. Compared with Application Example 1, the improvement in reaction current efficiency in Comparative Examples 2-4 was not significant, all below 50%. Therefore, the modification of graphite felt by hydroxyl acrylic resin, anthraquinones, amino-terminated polyaniline, and nano-transition metal particles has a synergistic effect on improving the electrochemical performance of the anode material.

[0160] It should be noted that the above content merely illustrates the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. For those skilled in the art, various improvements and modifications can be made without departing from the principle of the present invention, and all such improvements and modifications fall within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing a graphite felt anode material, characterized in that, Includes the following steps: (1) Pretreatment of graphite felt; (2) The nano-transition metal particles and the adhesive are mixed at a weight ratio of 2.4 to 5.2:1 to obtain a modifier; the graphite felt obtained in step (1) is immersed in the modifier, cured, washed and dried to obtain the graphite felt anode material. By weight, the adhesive comprises the following components: 10-30 parts of hydroxyl acrylic resin, 25-45 parts of anthraquinones, 15-30 parts of amino-terminated polyaniline, and 15-50 parts of solvent; The anthraquinones are one or more of emodin, aloe-emodin, and emodin methyl ether. The nano-transition metal particles are Pd and / or Pt; In step (1), the graphite felt pretreatment includes the following steps: using a three-electrode system to pretreat the graphite felt. Felt was used as the working electrode, platinum wire as the counter electrode, and an Ag / AgCl electrode as the reference electrode. Oxidation pretreatment was carried out in a dilute sulfuric acid electrolyte.

2. The method for preparing a graphite felt anode material according to claim 1, characterized in that, The mass ratio of anthraquinone substances to amino-terminated polyaniline in the adhesive is 1.5 to 1.6:

1.

3. The method for preparing a graphite felt anode material according to claim 1, characterized in that, The mass ratio of hydroxyl acrylic resin to amino-terminated polyaniline in the adhesive is 1 to 1.2:

1.

4. The method for preparing a graphite felt anode material according to claim 2, characterized in that, The amino-terminated polyaniline is a diamine-terminated aniline trimer.

5. The method for preparing a graphite felt anode material according to claim 3, characterized in that, The hydroxyl value of the hydroxyl acrylic resin is 13 to 38.5 mg KOH / g.

6. The method for preparing a graphite felt anode material according to claim 1, characterized in that, The particle size of the nano-transition metal particles is 2–4 nm.

7. The method for preparing a graphite felt anode material according to claim 1, characterized in that, In step (2), the impregnation process is as follows: the graphite felt obtained after pretreatment is completely impregnated in the modifier, ultrasonically mixed, the ultrasonic frequency is 10-25kHz, the ultrasonic time is 15-30min, and it is taken out after impregnation for 12h.

8. A graphite felt anode material, characterized in that, It is prepared by the method for preparing graphite felt anode material according to any one of claims 1-7.

9. An application of a graphite felt anode material, characterized in that, The graphite felt anode material of claim 8 is used as the anode electrode in the electrochemical synthesis process of dimethyl sebacate.

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