A Pd / WO x -C electrode and a method for preparing the same, use thereof

Abstract

This invention discloses a Pd / WO x -C electrode and its preparation method and application, step one, WO x -C support synthesis steps: WCl6 and C6H 12 O6 is dispersed and dissolved in C6H 14 In O4, a mixed solution is formed; the mixed solution undergoes a hydrothermal reaction to obtain WO4. x -C composite carrier; Step 2, WO x Preparation steps of -C supported palladium: The WO3 obtained in step one is used to prepare palladium. x The -C composite carrier was dispersed in water to obtain solution A; Na₂PdCl₄ was dispersed and dissolved in water to obtain solution B; solution B was added dropwise to solution A while continuously stirring; then the resulting mixed solution was placed in a water bath, heated to a certain temperature and kept at that temperature; after the reaction, Pd / WO₄ was obtained. x -C catalyst; Step 3, Pd / WO x -C electrode preparation steps: The Pd / WO3 obtained in step two... x -C catalyst was dispersed in a mixture, ultrasonicated, coated onto carbon paper, and dried to obtain Pd / WO4. x Electrode. Preparation of WO3 via hydrothermal method. x A C-C composite carrier was developed, and the Pd loading strategy was optimized to achieve high dechlorination efficiency while reducing the amount of precious metals used.

Description

Technical Field

[0001] This invention belongs to the field of electrocatalytic materials and environmental pollutant treatment technology, specifically relating to a Pd / WO3... x -C electrode, its preparation method, and applications. Background Technology

[0002] Chlorinated organic compounds are a class of persistent and recalcitrant pollutants widely found in industrial wastewater, soil, and groundwater. They are highly toxic, carcinogenic, and bioaccumulative, posing a serious threat to the ecological environment and human health. Electrocatalytic hydrodechlorination (ECH) technology has become an effective means of treating chlorinated organic compounds due to its mild reaction conditions and lack of secondary pollution. Noble metal Pd is a commonly used and highly efficient catalyst in electrocatalytic dechlorination reactions, exhibiting excellent catalytic activity for breaking C-Cl bonds. However, it suffers from problems such as high consumption of precious metals and high cost. Furthermore, single Pd catalysts have limited effectiveness in adsorbing hydrogen (H+). ads The limited production capacity of *) restricts its practical application in electrocatalytic dechlorination. Summary of the Invention

[0003] One of the objectives of this invention is to provide a Pd / WO x The preparation method of the -C electrode includes the following steps: Step 1, WO x -C support synthesis steps: WCl6 and C6H 12 O6 is dispersed and dissolved in C6H 14 In O4, a mixed solution is formed; the mixed solution undergoes a hydrothermal reaction to obtain WO4. x -C composite carrier; Step Two, WO x Preparation steps of -C-supported palladium: The WO3 obtained in step one... x -C composite carrier was dispersed in water to obtain solution A; Na₂PdCl₄ was dispersed and dissolved in water to obtain solution B; solution B was added to solution A and stirred until homogeneous to obtain a mixed solution; the resulting mixed solution was then heated to a certain temperature and held at that temperature; after the reaction, Pd / WO₄ was obtained. x -C catalyst; Step 3, Pd / WO x -C electrode preparation steps: The Pd / WO3 obtained in step two... x -C catalyst was dispersed in a mixed solvent, ultrasonicated, coated onto carbon paper, and dried to obtain Pd / WO3. x -C electrode.

[0004] As a preferred embodiment, in step one, WCl6 and C6H 12 The mass ratio of O6 is 1:0.5~3.

[0005] As a preferred embodiment, in step one, the hydrothermal reaction temperature is 120°C and the hydrothermal reaction time is 5 h.

[0006] As a preferred embodiment, in step two, WO x The mass ratio of the -C composite support to Na2PdCl4 is 50:1~6.

[0007] As a preferred embodiment, in step three, the Pd / WO content in each mL of the mixed solution is... x The amount of -C catalyst used was 15 mg.

[0008] As a preferred embodiment, in step three, the mixed solvent is prepared from Nafion solution, isopropanol, and ethanol.

[0009] This method prepares WO3 with high specific surface area via a hydrothermal method. x -C composite carrier; then Pd is loaded onto WO3 using an impregnation method. x -C carrier surface, finally the obtained Pd / WO x -C catalyst is mixed with binder and dispersant to form a slurry, which is then coated onto the surface of carbon paper to obtain Pd / WO3. x -C electrode. The loading of the noble metal Pd in ​​this electrode is only 0.0085 mg cm⁻¹. -2 It can efficiently achieve electrocatalytic hydrodechlorination of 2,4-DCP under mild reaction conditions, providing a practical technical solution for the low-cost and efficient treatment of chlorinated organic pollutants.

[0010] The second objective of this invention is to provide a Pd / WO x -C electrode, which is prepared by any of the preparation methods described above.

[0011] A third objective of this invention is to provide a Pd / WO according to the above description. x The application of the -C electrode involves using an H-type dual-chamber electrochemical reactor for the dechlorination reaction, which is carried out under constant current conditions. The cathode chamber contains a solution of 2,4-DCP and Na₂SO₄, while the anode chamber contains a solution of Na₂SO₄. The cathode is connected to the Pd / WO₄ reactor described in claim 7. x -C electrode, with a platinum sheet connected to the anode.

[0012] As a preferred option, the cathode chamber is stirred using a stirrer to avoid concentration polarization.

[0013] To address the aforementioned problems, this invention prepares a composite catalyst by supporting Pd on a support, thereby enhancing catalytic performance through the interaction between the support and Pd. Carbon materials, due to their high specific surface area, good conductivity, and stability, are used as catalyst supports; while transition metal oxides (WO3)... xIt has a unique electronic structure that allows for the control of electron distribution on the carrier surface, promoting H ads The generation of * enhances the catalytic activity of Pd. WO3... x Combined with carbon materials to form WO x -C support can leverage the high specific surface area of ​​carbon materials while also utilizing WO3. x The electronic regulation effect provides a stable and efficient loading environment for Pd. Therefore, this invention, by developing a composite electrode material that combines high conductivity, high active site exposure, and low noble metal content, is of great significance for improving the efficiency of electrocatalytic hydrodechlorination and reducing costs.

[0014] To achieve the above objectives and solve the aforementioned problems in the prior art, Pd / WO3 prepared using the raw materials and method of this invention... x -C electrode, WO3 prepared by hydrothermal method x By using a -C composite carrier and optimizing the Pd loading strategy, high dechlorination efficiency is achieved while reducing the amount of precious metals used, providing a new solution for the efficient treatment of chlorinated organic pollutants.

[0015] The present invention has the following beneficial effects: Firstly, this invention optimizes the electrode preparation method, employing a one-step hydrothermal method to synthesize WO3. x -C carrier, simple process, low energy consumption; the obtained WO x -C support exhibits a nanowire network structure with high specific surface area and abundant pores, providing ample loading sites for Pd, effectively inhibiting Pd particle aggregation, and promoting mass transfer between the electrolyte and reactants. Meanwhile, WO... x The synergistic effect with carbon materials can improve the conductivity and electron transfer efficiency of the support. This method uses WCl6 as the tungsten source and C6H... 12 Using O6 as a carbon source, WO3 with a high specific surface area was prepared via a hydrothermal method. x -C composite carrier; then Pd is loaded onto WO3 using an impregnation method. x -C carrier surface, finally the obtained Pd / WO x -C catalyst is mixed with binder and dispersant to form a slurry, which is then coated onto the surface of carbon paper to obtain Pd / WO3. x -C electrode. The loading of the noble metal Pd in ​​this electrode is only 0.0085 mg cm⁻¹. -2 When used as a cathode in the electrocatalytic hydrodechlorination reaction of 2,4-DCP, the dechlorination efficiency of 2,4-DCP reached 94.9% after 3 hours of reaction under ambient temperature and pressure, with a specific catalytic activity of 0.154 mol·h⁻¹ for Pd. -1 ·g -1 It exhibits high catalytic activity.

[0016] Secondly, the Pd / WO prepared by this invention x -C electrode, with a Pd loading of only 0.0085 mg cm⁻¹. -2 This significantly reduces the consumption of precious metals and effectively lowers the manufacturing cost of electrodes. Simultaneously, by utilizing WO3... x The structural advantages and synergistic catalytic effect of the -C support enable this electrode to exhibit excellent catalytic activity in the dechlorination reaction of 2,4-DCP, achieving a dechlorination efficiency of up to 94.9%, thus achieving synergistic optimization of low precious metal usage and high catalytic efficiency. The composite electrode prepared by this invention has the advantages of low precious metal usage, simple preparation process, and environmental friendliness, and has important application value in the electrocatalytic hydrodechlorination treatment of chlorinated organic pollutants. Attached Figure Description

[0017] Figure 1 For WO x SEM image of the carrier; Figure 2 WO in Example 4 x SEM image of -C(1:1); Figure 3 Pd / WO in Example 4 x SEM image of the -C(1:1) electrode; Figure 4 The degradation effect of the electrode pairs 2,4-DCP prepared in Examples 1-8 is shown in the figure. Figure 5 The graph shows the degradation effect of the electrode pairs prepared in Examples 4, 9, 10, 11 and 12 on 2,4-DCP. Figure 6 The degradation effect of the electrode pairs 2,4-DCP prepared in Examples 1, 4, 1, 2 and 3 is shown in the figure. Detailed Implementation

[0018] To make the technical means, creative features, objectives, and beneficial effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0019] In addition, to better illustrate the present invention, numerous specific details are given in the following detailed embodiments. Those skilled in the art should understand that the present invention can be implemented even without certain specific details. In other embodiments, methods, means, equipment and steps well known to those skilled in the art are not described in detail in order to highlight the main points of the present invention.

[0020] The carbon paper was purchased from TORAY Corporation of Japan, product model: TGP-H-060; the high performance liquid chromatograph used in the embodiments and comparative examples of this scheme was Dalian Elite P230II; the infrared lamp was 220 V, power 100 W.

[0021] Unless otherwise specified, all materials and reagents used below are commercially available. Experimental methods not specifically described in the examples are generally performed under conventional conditions in the prior art or as recommended by the manufacturer.

[0022] Example 1: Pd / WO x Electrode preparation and dechlorination performance testing 1. WO x Preparation of the support: 0.8 g WCl6 was ultrasonically dispersed in 80 mL of C6H4O2. 14 The reaction solution was hydrothermally reacted in O4 at 120℃ for 5 h; the reaction solution was centrifuged at 8000 rpm for 8 min, washed four times with ethanol, and freeze-dried at -50℃ for 24 h to obtain WO4. x Carrier.

[0023] 2. WO x Preparation of palladium supported on a carrier. 100 mg of WO3 was used... x The carrier was dispersed in 100 mL of deionized water (to obtain solution A), and 4 mg of Na₂PdCl₄ was dissolved in 50 mL of deionized water (to obtain solution B). Solution B was added dropwise to solution A at a rate of 0.8 mL / min, while stirring continuously at 400 rpm for 24 h. The solution was then incubated in a 90 °C water bath for 30 min. After centrifugation at 8000 rpm for 8 min, the solution was washed four times with ethanol and freeze-dried at -50 °C for 24 h to obtain the target product Pd / WO₄. x .

[0024] 3. Pd / WO x Electrode preparation. Weigh 60 mg of Pd / WO3. x The catalyst was added to a mixed solvent of 40 μL 5wt% Nafion solution, 1 mL isopropanol, and 3 mL ethanol, sonicated for 30 min, coated onto carbon paper, and dried under an infrared lamp to obtain Pd / WO4. x Electrode. The Pd loading on the electrode surface was determined to be 0.0085 mg / cm² by inductively coupled plasma optical emission spectrometry (ICP-OES). -2 .

[0025] 4. Dechlorination performance test. The Pd / WO3 prepared in Example 1 was used... xThe cathode was used for the electrocatalytic hydrodechlorination of 2,4-DCP. The dechlorination reaction was carried out in an H-type two-chamber electrochemical reactor under constant current conditions. The cathode chamber contained 80 mL of 2,4-DCP containing 50 mg L⁻¹. -1 2,4-DCP and 50 mmol L -1 A solution of Na₂SO₄. The anode chamber contains 80 mL of 50 mmol / L solution. -1 A solution of Na₂SO₄. Cathode connection: Pd / WO₄. x The cathode chamber was agitated with a platinum sheet, and a magnetic stirrer was used to agitate the cathode chamber at 300 rpm to prevent concentration polarization. The current density was controlled at 1 mA cm⁻¹. -2 The reaction was carried out at 25℃ for 3 h. 0.5 mL of the cathode chamber sample was taken every 30 min, and the concentration change of 2,4-DCP was determined by high-performance liquid chromatography (HPLC) (Dalian Elite, P230II). The UV detector wavelength was set to 280 nm, the mobile phase was methanol and pure water (60:40 v / v), and the flow rate was 1 mL / min. -1 .

[0026] Experimental results show that Pd / WO x The dechlorination efficiency of the electrode can reach 27.1%.

[0027] Figure 1 It is WO x The SEM image of the carrier shows an irregular particle aggregate structure with a wide particle size distribution, few pore structures, and a relatively dense overall packing.

[0028] Example 2: Pd / WO x Preparation and dechlorination performance testing of -C(1:0.1) electrode 1. WO x Preparation of -C support. The preparation method and process are the same as in Example 1, except that 0.08 g of C6H was added during the hydrothermal reaction. 12 O6, the final product is denoted as WO x -C(1:0.1).

[0029] 2. WO x Preparation of palladium supported on a C-C support. The preparation method and process are the same as in Example 1, except that the support is replaced with WO4. x -C(1:0.1), the final product is denoted as Pd / WO. x -C(1:0.1).

[0030] 3. WO x Preparation of a palladium electrode supported on a C-carrier. The preparation method and process are the same as in Example 1, except that the electrode is designated as Pd / WO3. x-C(1:0.1). ICP-OES testing showed that the load on Pd was essentially the same as in Example 1.

[0031] 4. Dechlorination performance test. The test method and procedure are the same as in Example 1, except that the electrode is replaced with Pd / WO3. x -C (1:0.1).

[0032] Experimental results show that Pd / WO x The dechlorination efficiency of the -C(1:0.1) electrode can reach 34.7%.

[0033] Example 3: Pd / WO x Preparation and dechlorination performance testing of -C(1:0.5) electrode 1. WO x Preparation of -C support. The preparation method and process are the same as in Example 1, except that 0.4 g of C6H was added during the hydrothermal reaction. 12 O6, the final product is denoted as WO x -C(1:0.5).

[0034] 2. WO x Preparation of palladium supported on a C-C support. The preparation method and process are the same as in Example 1, except that the support is replaced with WO4. x -C(1:0.5). The final product obtained is denoted as Pd / WO. x -C(1:0.5).

[0035] 3. WO x Preparation of a palladium electrode supported on a C-carrier. The preparation method and process are the same as in Example 1, except that the electrode is designated as Pd / WO3. x -C(1:0.5). ICP-OES testing showed that the load on Pd remained essentially unchanged.

[0036] 4. Dechlorination performance test. The preparation method and process are the same as in Example 1, except that the electrode is replaced with Pd / WO3. x -C(1:0.5).

[0037] Experimental results show that Pd / WO x The dechlorination efficiency of the -C(1:0.5) electrode can reach 52.1%.

[0038] Example 4: Pd / WO x Preparation and dechlorination performance testing of -C(1:1) electrode 1. WO x Preparation of -C support. The preparation method and process are the same as in Example 1, except that 0.8 g of C6H was added during the hydrothermal reaction. 12O6, the final product is denoted as WO x -C(1:1).

[0039] 2. WO x Preparation of palladium supported on a C-C support. The preparation method and process are the same as in Example 1, except that the support is replaced with WO4. x -C(1:1), the final product is denoted as Pd / WO. x -C(1:1).

[0040] 3. WO x Preparation of a palladium electrode supported on a C-carrier. The preparation method and process are the same as in Example 1, except that the electrode is designated as Pd / WO3. x -C(1:1), according to ICP-OES testing, the load on Pd remains basically unchanged.

[0041] 4. Dechlorination performance test. The test method and procedure are the same as in Example 1, except that the electrode is replaced with Pd / WO3. x -C(1:1).

[0042] Figure 2 It is WO x SEM image of -C(1:1), and WO x In contrast, the C-doped sample exhibited a fluffy nanowire network with a small amount of porous flocculent morphology, and the pore structure began to develop.

[0043] Figure 3 Is Pd / WO x The SEM image of -C(1:1) shows that the sample exhibits a nanowire network structure, with further optimized particle dispersion, rich and uniformly distributed pore structure, and significantly improved specific surface area.

[0044] Experimental results show that Pd / WO x The dechlorination efficiency of the -C(1:1) electrode can reach 94.9%.

[0045] Example 5: Pd / WO x Preparation and dechlorination performance testing of -C(1:2) electrode 1. WO x Preparation of the -C support. The preparation method and process are the same as in Example 1, except that 1.6 g of C6H was added during the hydrothermal reaction. 12 O6, the final product is denoted as WO x -C(1:2).

[0046] 2. WO x Preparation of palladium supported on a C-C support. The preparation method and process are the same as in Example 1, except that the support is replaced with WO4. x-C(1:2). The final product obtained is denoted as Pd / WO. x -C(1:2).

[0047] 3. WO x Preparation of a palladium electrode supported on a C-carrier. The preparation method and process are the same as in Example 1, except that the electrode is designated as Pd / WO3. x -C(1:2). ICP-OES testing showed that the load on Pd remained essentially unchanged.

[0048] 4. Dechlorination performance test. The test method and procedure are the same as in Example 1, except that the electrode is replaced with Pd / WO3. x -C(1:2).

[0049] Experimental results show that Pd / WO x The dechlorination efficiency of the -C(1:2) electrode can reach 82.4%.

[0050] Example 6: Pd / WO x Preparation and dechlorination performance testing of -C(1:3) electrode 1. WO x Preparation of -C support. The preparation method and process are the same as in Example 1, except that 2.4 g of C6H was added during the hydrothermal reaction. 12 O6, the final product is denoted as WO x -C(1:3).

[0051] 2. WO x Preparation of palladium supported on a C-C support. The preparation method and process are the same as in Example 1, except that the support is replaced with WO4. x -C(1:3). The final product obtained is denoted as Pd / WO. x -C(1:3).

[0052] 3. WO x Preparation of a palladium electrode supported on a C-carrier. The preparation method and process are the same as in Example 1, except that the electrode is designated as Pd / WO3. x -C(1:3). ICP-OES testing showed that the load on Pd remained essentially unchanged.

[0053] 4. Dechlorination performance test. The test method and procedure are the same as in Example 1, except that the electrode is replaced with Pd / WO3. x -C(1:3).

[0054] Experimental results show that Pd / WO x The dechlorination efficiency of the -C(1:3) electrode can reach 57.9%.

[0055] Example 7: Pd / WO xPreparation and dechlorination performance testing of -C(1:3.5) electrode 1. WO x Preparation of -C support. The preparation method and process are the same as in Example 1, except that 2.8 g of C6H was added during the hydrothermal reaction. 12 O6, the final product is denoted as WO x -C(1:3.5).

[0056] 2. WO x Preparation of palladium supported on a C-C support. The preparation method and process are the same as in Example 1, except that the support is replaced with WO4. x -C(1:3.5). The final product obtained is denoted as Pd / WO. x -C(1:3.5).

[0057] 3. WO x Preparation of a palladium electrode supported on a C-carrier. The preparation method and process are the same as in Example 1, except that the electrode is designated as Pd / WO3. x -C(1:3.5). ICP-OES testing showed that the load on Pd remained essentially unchanged.

[0058] 4. Dechlorination performance test. The test method and procedure are the same as in Example 1, except that the electrode is replaced with Pd / WO3. x -C(1:3.5).

[0059] Experimental results show that Pd / WO x The dechlorination efficiency of the -C(1:3.5) electrode reached 42.2%.

[0060] Example 8: Pd / WO x Preparation and dechlorination performance testing of -C(1:4) electrode 1. WO x Preparation of -C support. The preparation method and process are the same as in Example 1, except that 3.2 g of C6H was added during the hydrothermal reaction. 12 O6, the final product is denoted as WO x -C(1:4).

[0061] 2. WO x Preparation of palladium supported on a C-C support. The preparation method and process are the same as in Example 1, except that the support is replaced with WO4. x -C(1:4). The final product obtained is denoted as Pd / WO. x -C(1:4).

[0062] 3. WO x Preparation of a palladium electrode supported on a C-carrier. The preparation method and process are the same as in Example 1, except that the electrode is designated as Pd / WO3.x -C(1:4). ICP-OES testing showed that the load on Pd remained essentially unchanged.

[0063] 4. Dechlorination performance test. The test method and procedure are the same as in Example 1, except that the electrode is replaced with Pd / WO3. x -C(1:4).

[0064] Experimental results show that Pd / WO x The dechlorination efficiency of the -C(1:4) electrode reached 23.1%.

[0065] Depend on Figure 4 It can be seen that different WCl6 and C6H 12 Pd / WO prepared by O6 mass ratio x When the -C cathode is applied to the electrocatalytic hydrodechlorination reaction of 2,4-DCP, the dechlorination effect exhibits a clear and regular change: when C6H 12 When the amount of O6 added is 0, WO x Due to its small specific surface area and few pores, the carrier allows Pd particles to easily aggregate, resulting in insufficient exposure of active sites and a dechlorination efficiency of 27.1%. With the development of C6H... 12 The addition of O6 gradually increases the dechlorination conversion rate, especially when WCl6 reacts with C6H. 12 When the O6 mass ratio is 1:1, the dechlorination efficiency reaches 94.9%, which is because C doping optimizes WO3 at this ratio. x The network porous structure of the -C carrier not only improves Pd dispersion but also enhances the carrier's conductivity and mass transfer efficiency. x The synergistic effect with C gradually strengthens; however, when the mass ratio exceeds 1:1, the dechlorination efficiency tends to decrease, presumably because excess C covers some active sites, leading to a weakening of the synergistic catalytic efficiency. In summary, in this invention, Pd / WO... x -Optimal WCl6 and C6H at the C electrode 12 The dechlorination efficiency is highest when the O6 mass ratio is 1:1.

[0066] Based on the above experimental results, WCl6 and C6H were selected. 12 The optimal O6 mass ratio is 1:1. The following examples were conducted by adjusting the amount of Na2PdCl4.

[0067] Example 9: 0.002 mg cm -2 Pd / WO x Preparation and dechlorination performance testing of -C(1:1) electrode 1. WO x Preparation of the -C carrier. The preparation method and process are the same as in Example 4.

[0068] 2. WO xPreparation of palladium supported on a -C carrier. The preparation method and process are the same as in Example 4, except that the amount of Na2PdCl4 used is 1 mg.

[0069] 3. WO x Preparation of a palladium electrode supported on a C-type carrier. The preparation method and process are the same as in Example 4, except that the amount of Na2PdCl4 used is 1 mg, and the Pd loading on the electrode surface is 0.002 mg / cm² as determined by ICP-OES. -2 The electrode was recorded as 0.002 mg cm. -2 Pd / WO x -C(1:1).

[0070] 4. Dechlorination performance test. The test method and procedure are the same as in Example 4, except that the electrode is replaced with a 0.002 mg cm⁻¹ electrode. -2 Pd / WO x -C(1:1).

[0071] Experimental results show that 0.002 mg cm -2 Pd / WO x The dechlorination efficiency of the -C(1:1) electrode is 19.4%.

[0072] Example 10: 0.0043 mg cm -2 Pd / WO x Preparation and dechlorination performance testing of -C(1:1) electrode 1. WO x Preparation of the -C carrier. The preparation method and process are the same as in Example 4.

[0073] 2. WO x Preparation of palladium supported on a -C carrier. The preparation method and process are the same as in Example 4, except that the amount of Na2PdCl4 used is 2 mg.

[0074] 3. WO x Preparation of a palladium electrode supported on a C-type carrier. The preparation method and process are the same as in Example 4, except that the amount of Na2PdCl4 used is 2 mg, and the Pd loading on the electrode surface, as determined by ICP-OES, is 0.0043 mg / cm³. -2 The electrode was recorded as 0.0043 mg cm. -2 Pd / WO x -C(1:1).

[0075] 4. Dechlorination performance test. The test method and procedure are the same as in Example 4, except that the electrode is replaced with a 0.0043 mg cm⁻¹ electrode. -2 Pd / WO x-C(1:1).

[0076] Experimental results show that 0.0043 mg cm -2 Pd / WO x The dechlorination efficiency of the -C(1:1) electrode can reach 33.1%.

[0077] Example 11: 0.0183 mg cm -2 Pd / WO x Preparation and dechlorination performance testing of -C(1:1) electrode 1. WO x Preparation of the -C carrier. The preparation method and process are the same as in Example 4.

[0078] 2. WO x Preparation of palladium supported on a -C carrier. The preparation method and process are the same as in Example 4, except that the amount of Na2PdCl4 used is 6 mg.

[0079] 3. WO x Preparation of a palladium electrode supported on a C-type carrier. The preparation method and process are the same as in Example 4, except that the amount of Na2PdCl4 used is 6 mg, and the Pd loading on the electrode surface, as determined by ICP-OES, is 0.0183 mg / cm³. -2 The electrode was recorded as 0.0183 mg cm⁻¹. -2 Pd / WO x -C(1:1).

[0080] 4. Dechlorination performance test. The test method and procedure are the same as in Example 4, except that the electrode is replaced with a 0.0183 mg cm⁻¹ electrode. -2 Pd / WO x -C(1:1).

[0081] Experimental results show that 0.0183 mg cm -2 Pd / WO x The dechlorination efficiency of the -C(1:1) electrode can reach 64.3%. In this embodiment, the increase in the actual Pd loading is greater than the increase in the precursor loading, which is consistent with the normal characteristics of carrier loading.

[0082] Example 12: 0.031 mg cm -2 Pd / WO x Preparation and dechlorination performance testing of -C(1:1) electrode 1. WO x Preparation of the -C carrier. The preparation method and process are the same as in Example 4.

[0083] 2. WO xPreparation of palladium supported on a -C carrier. The preparation method and process are the same as in Example 4, except that the amount of Na2PdCl4 used is 12 mg.

[0084] 3. WO x Preparation of a palladium electrode supported on a C-type carrier. The preparation method and process are the same as in Example 4, except that the amount of Na2PdCl4 used is 12 mg, and the Pd loading on the electrode surface, as determined by ICP-OES, is 0.031 mg / cm³. -2 The electrode was recorded as 0.031 mg cm. -2 Pd / WO x -C(1:1).

[0085] 4. Dechlorination performance test. The test method and procedure are the same as in Example 4, except that the electrode is replaced with a 0.031 mg cm⁻¹ electrode. -2 Pd / WO x -C(1:1).

[0086] Experimental results show that 0.031 mg cm -2 Pd / WO x The dechlorination efficiency of the -C(1:1) electrode can reach 46.1%.

[0087] Depend on Figure 5 It can be seen that when the Pd loading is 0.002 mg cm⁻¹ -2 At this point, the dechlorination efficiency was 19.4%, indicating an insufficient number of Pd active sites to fully meet the reaction requirements for 2,4-DCP molecule adsorption and C-Cl bond breaking, thus limiting catalytic performance. When the Pd loading was increased to 0.0085 mg cm⁻¹... -2 At this loading level, the dechlorination efficiency significantly increased to 94.9%, and Pd was uniformly dispersed in WO3. x -C carrier surface, Pd and WO x The metal-support interaction of the -C support achieved optimal dechlorination performance; and further increasing to 0.031 mg cm⁻¹... -2 The dechlorination efficiency dropped to 46.1%, while excessive loading may lead to reduced catalytic activity due to factors such as Pd particle agglomeration, carrier pore blockage, and impeded electron transport.

[0088] Comparative Example 1: WO x Electrode preparation and dechlorination performance testing 1. WO x Preparation of the carrier. The preparation method and process are the same as in Example 1.

[0089] 2. WO xElectrode preparation. The preparation method and process are the same as in Example 1, except that 60 mg of WO3 was weighed. x Carrier.

[0090] 3. Dechlorination performance test. The test method and procedure are the same as in Example 1. The only difference is that the electrode is replaced with WO3. x .

[0091] Experimental results show that WO x The electrode had almost no dechlorination effect.

[0092] Comparative Example 2: WO x Preparation and dechlorination performance testing of -C(1:1) electrode 1. WO x Preparation of -C support. The preparation method and process are the same as in Example 1, except that 0.8 g of C6H was added during the hydrothermal reaction. 12 O6, the final product is denoted as WO x -C(1:1).

[0093] 2. Dechlorination performance test. The test method and procedure are the same as in Example 1. The only difference is that the electrode is replaced with WO3. x -C(1:1).

[0094] Experimental results show that WO x -C(1:1) electrodes have almost no dechlorination effect.

[0095] Comparative Example 3: Preparation and Dechlorination Performance Testing of Pd / C Electrode 1. Preparation of C-carrier. The preparation method and process are the same as in Example 1, except that WCl6 was not used; instead, 0.8g of C6H... 12 O6 was ultrasonically dispersed in C6H 14 O4, hydrothermal reaction yields C support.

[0096] 2. Preparation of palladium supported on C. The preparation method and process are the same as in Example 1, except that the support is replaced with C, and the final product is denoted as Pd / C.

[0097] 3. Preparation of the Pd / C electrode. The preparation method and process are the same as in Example 1, except that the electrode is designated as Pd / C. ICP-OES testing showed that the Pd loading remained essentially unchanged.

[0098] 4. Dechlorination performance test. The test method and procedure are the same as in Example 1. The only difference is that the electrode is replaced with Pd / C.

[0099] Experimental results show that the dechlorination efficiency of the Pd / C electrode can reach 34.6%.

[0100] Depend on Figure 6 It can be seen that the dechlorination performance of different electrodes varies significantly: WO x Electrodes and WO x -C(1:1) electrodes showed virtually no dechlorination activity; while after Pd loading, the Pd / WO4 ratio... x The dechlorination efficiency of the electrode reached 27.1%, and that of the Pd / C electrode reached 34.6%, proving that Pd is the key component for catalytic activity; further optimization of the support structure was used to prepare Pd / WO x The -C(1:1) electrode exhibited an excellent dechlorination efficiency of 94.9%. These comparative results fully demonstrate that the introduction of the noble metal Pd is a necessary condition for obtaining catalytic activity; by constructing WO3... x -C composite supports can significantly improve the catalytic efficiency of Pd, with its dechlorination performance being about 3.5 times higher than that of single support systems. This is attributed to the optimized electronic structure and higher specific surface area of ​​the composite support.

[0101] In this invention, the actual Pd loading on the electrode surface is obtained by ICP-OES measurement. Because WO x -C The surface of the carrier has a large number of active loading sites. When the amount of precursor Na2PdCl4 is low, the sites on the carrier surface are in an unsaturated state, and the loading efficiency of the precursor is high. As the amount of precursor increases, the loading rate of Pd on the carrier increases synchronously. Therefore, in some embodiments, the increase in the actual loading amount of Pd will be greater than the increase in the amount of precursor.

[0102] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A Pd / WO x The method for preparing a -C electrode is characterized by: Includes the following steps: Step 1, WO x -C support synthesis steps: WCl6 and C6H 12 O6 is dispersed and dissolved in C6H 14 In O4, a mixed solution is formed; the mixed solution undergoes a hydrothermal reaction to obtain WO4. x -C composite carrier; Step Two, WO x Preparation steps of -C-supported palladium: The WO3 obtained in step one... x -C composite carrier was dispersed in water to obtain solution A; Na₂PdCl₄ was dispersed and dissolved in water to obtain solution B; solution B was added to solution A and stirred until homogeneous to obtain a mixed solution; the resulting mixed solution was then heated to a certain temperature and held at that temperature; after the reaction, Pd / WO₄ was obtained. x -C catalyst; Step 3, Pd / WO x -C electrode preparation steps: The Pd / WO3 obtained in step two... x -C catalyst was dispersed in a mixed solvent, ultrasonicated, coated onto carbon paper, and dried to obtain Pd / WO3. x -C electrode.

2. A Pd / WO3 according to claim 1 x The method for preparing a -C electrode is characterized by: In step one, WCl6 and C6H 12 The mass ratio of O6 is 1:0.5~3.

3. A Pd / WO3 according to claim 1 x The method for preparing a -C electrode is characterized by: In step one, the hydrothermal reaction temperature is 120℃ and the hydrothermal reaction time is 5 h.

4. A Pd / WO3 according to claim 1 x The method for preparing a -C electrode is characterized by: In step two, WO x The mass ratio of the -C composite support to Na2PdCl4 is 50:1~6.

5. A Pd / WO3 according to claim 1 x The method for preparing a -C electrode is characterized by: In step three, the Pd / WO content per mL of the mixed solution x The amount of -C catalyst used was 15 mg.

6. A Pd / WO3 according to claim 1 x The method for preparing a -C electrode is characterized by: In step three, the mixed solvent is prepared from Nafion solution, isopropanol and ethanol.

7. A Pd / WO x -C electrode, characterized in that: It is prepared by the preparation method described in any one of claims 1-6.

8. A Pd / WO3 according to claim 7 x The application of the -C electrode is characterized by: The dechlorination reaction is carried out using an H-type dual-chamber electrochemical reactor under constant current conditions; the cathode chamber contains a solution of 2,4-DCP and Na2SO4, and the anode chamber contains a solution of Na2SO4. The cathode is connected to the Pd / WO4 reactor described in claim 7. x -C electrode, with a platinum sheet connected to the anode.

9. A Pd / WO3 according to claim 8 x The application of the -C electrode is characterized by: A stirrer is used to agitate the cathode chamber to prevent concentration polarization.

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