Electrolytic adsorption device and application thereof

Abstract

The invention relates to the technical field of chlorine-containing electronic wastewater treatment, in particular to an electrolytic adsorption device and application thereof. The invention provides an electrolytic adsorption device. The electrolytic adsorption device comprises anodes and cathodes which are alternately arranged in parallel, the anode comprises an anode substrate and an anode material coated on the surface of the anode substrate; the anode substrate comprises a titanium foil and a titanium dioxide nanotube layer on the surface of the titanium foil, and the titanium dioxide nanotube layer is of a three-dimensional array structure; the anode material is a composite material of SnO2, Sb and RuO2; the cathode comprises a cathode substrate and a cathode material coated on the surface of the cathode substrate, and the cathode material is a mixture comprising a carbon-based material and ferroferric oxide. The electrolytic adsorption device is low in cost, the requirement conditions for chlorine-containing electronic wastewater treatment are not strict, COD can be effectively removed, and / or the high heavy metal (Cu < 2 + >) recovery rate is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of chlorine-containing electronic wastewater treatment, and in particular to an electrolytic adsorption device and application thereof. Background Art

[0002] Electronic products are becoming increasingly important in our daily lives. Printed circuit boards (PCBs), the substrates used to assemble electronic components, are the core components of electronic products. Their primary function is to connect various electronic components through circuits, providing conduction and transmission, making them key electronic interconnects in electronic products.

[0003] The production process for electronic components is extremely complex, and wastewater is generated at every stage of production. This includes strong acid and alkaline wastewater, high-concentration organic wastewater, and wastewater containing heavy metals such as copper, zinc, nickel, and chromium. The water quality is complex and varies widely. Due to the large number and widespread distribution of electronics companies, the total discharge volume is very large, with approximately 400 million tons of high-concentration wastewater containing heavy metals discharged annually. Electronic wastewater is a type of wastewater with high CODcr concentrations, often reaching 5,000 to 10,000 mg / L, and sometimes even as high as 20,000 mg / L. Due to its complex composition and high content of difficult-to-degrade organic matter, it is difficult to properly treat. Therefore, for the treatment of PCB wastewater, whether the wastewater CODcr can meet discharge standards (<100 mg / L) depends primarily on the effectiveness of the wastewater treatment.

[0004] In terms of water pollutant emissions, heavy metal pollutants emitted by the electronics manufacturing industry, represented by printed circuit boards (PCBs), account for over 95% of the total. Due to process requirements, wastewater from the electronics industry, such as PCBs, often contains large amounts of chloride ions and heavy metals. The treatment of chlorine-containing wastewater has long been a challenge in water treatment processes. Heavy metals are highly toxic, difficult to metabolize in the environment, difficult to degrade to harmless forms under natural conditions, and prone to bioaccumulation and biochemical effects. They can enter the human body through the food chain, causing harm to human health. Therefore, electronic wastewater has become one of the most serious industrial wastewaters that pollute the environment and pose the greatest threat to human health.

[0005] After electronic wastewater is treated using traditional technologies (chemical precipitation, adsorption, biological methods, etc.), its pollutant concentration is controlled to meet discharge requirements before it can be discharged. However, the large amount of heavy metal pollutants removed are converted into chemical or biological sludge. This essentially converts water pollution into solid waste pollution, resulting in a failure to truly address the heavy metal hazards. On the other hand, "waste is a misplaced resource." The metals in wastewater are often expensive heavy metals. If they can be effectively recovered, valuable heavy metal resources can be recycled, turning waste into treasure, effectively controlling pollution emissions and addressing pollution problems at the source. For example, copper ions in PCB wastewater typically exist in free and complexed forms. Electrolytic treatment of copper-containing wastewater can achieve a 90% recovery rate of metallic copper, offering high economic benefits. Therefore, recycling the large amount of heavy metal resources contained in electronic wastewater, a high-volume process, not only improves economic benefits for enterprises but also maximizes wastewater resource utilization.

[0006] At present, the problems that need to be solved in the treatment of electronic wastewater pollution include: (1) the stable operation of wastewater treatment facilities to ensure that the chloride ions, COD and heavy metal ions in the wastewater all meet the requirements of the "Electroplating Pollutant Discharge Standard" (GB21900-2008); (2) reducing operating costs on the basis of meeting the standards and improving the reuse rate of electroplating wastewater; (3) realizing resource utilization of heavy metals / precious metals in electroplating wastewater, turning it into "waste". The traditional treatment processes for electronic wastewater at home and abroad mainly include chemical precipitation, ion exchange, membrane separation, electrolysis, adsorption, biological treatment, etc., but these methods have certain limitations. The precipitation method requires a large amount of chemical reagents, has little effect on the removal of chloride ions and organic matter, and produces a large amount of chemical sludge, which increases the treatment cost. The biological treatment method has a high requirement for the influent concentration (CODcr <1000mg / L), so the wastewater needs to be pretreated or diluted, and the hydraulic retention time is long (HRT>16h). The adsorption method requires a large amount of adsorbent, has a low treatment rate, high operating costs, and is prone to clogging. Summary of the Invention

[0007] In view of this, an object of the present invention is to provide an electrolytic adsorption device, which has low cost, is not strict in the treatment conditions for chlorine-containing electronic wastewater, and can effectively remove COD and / or has a high heavy metal recovery rate.

[0008] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0009] The present invention provides an electrolytic adsorption device, comprising anodes and cathodes alternately arranged in parallel;

[0010] The anode comprises an anode substrate and an anode material coated on the surface of the anode substrate; the anode substrate comprises a titanium foil and a titanium dioxide nanotube layer on the surface of the titanium foil, wherein the titanium dioxide nanotube layer is a three-dimensional array structure; the anode material is a composite material of SnO2, Sb and RuO2;

[0011] The cathode includes a cathode substrate and a cathode material coated on the surface of the cathode substrate. The cathode material is a mixture of carbon-based materials and ferrosoferric oxide.

[0012] Preferably, the alternating parallel arrangement is repeated three times.

[0013] Preferably, the mass ratio of the anode material to the anode substrate is (1-10):100;

[0014] The titanium dioxide nanotubes in the anode substrate have a length of 0.2 to 41 μm, an outer diameter of 10 to 100 nm, and a wall thickness of 10 to 20 nm.

[0015] Preferably, the mass ratio of SnO2, Sb and RuO2 in the composite material of SnO2, Sb and RuO2 is 70:10:20.

[0016] Preferably, the preparation process of the anode comprises the following steps:

[0017] Using titanium foil as a working anode, platinum sheet as a cathode, and a solution containing fluoride ions as an electrolyte, an anodic oxidation reaction is carried out, followed by heat treatment to obtain an anode substrate;

[0018] preparing a precursor solution;

[0019] After the precursor solution is sprayed on the surface of the anode substrate, thermal decomposition is performed to obtain the anode.

[0020] Preferably, the concentration of fluoride ions in the electrolyte is 0.2 to 2 mg / L;

[0021] The voltage of the anodic oxidation reaction is 10 to 30 V, and the time is 2 hours;

[0022] The heat treatment temperature is 400-600° C., and the heat preservation time is 3 hours.

[0023] Preferably, the mass ratio of the carbon-based material to ferrosoferric oxide in the cathode material is 100:(2-10);

[0024] The carbon-based material includes one or more of activated carbon, carbon nanotubes and carbon black.

[0025] Preferably, the cathode preparation process comprises the following steps:

[0026] The cathode is obtained by coating a dispersion containing ferrosoferric oxide and a carbon-based material on the surface of a cathode substrate.

[0027] The present invention also provides the use of the electrolytic adsorption device described in the above technical solution in treating chlorine-containing electronic wastewater.

[0028] Preferably, the application method comprises the following steps:

[0029] The chlorine-containing electronic wastewater is passed into the electrolytic adsorption device for treatment.

[0030] Preferably, the flow rate of the chlorine-containing electronic wastewater is 0.1 to 2 mL / min;

[0031] The working current of the treatment is 2-20 mA / cm 2 , the voltage is 2V.

[0032] The present invention provides an electrolytic adsorption device, comprising an anode and a cathode arranged alternately in parallel; the anode comprises an anode substrate and an anode material coated on the surface of the anode substrate; the anode substrate comprises a titanium foil and a titanium dioxide nanotube layer on the surface of the titanium foil, the titanium dioxide nanotube layer being a three-dimensional array structure; the anode material is a composite material of SnO2, Sb, and RuO2; the cathode comprises a cathode substrate and a cathode material coated on the surface of the cathode substrate, the cathode material being a mixture of a carbon-based material and ferroferric oxide. The electrolytic adsorption device of the present invention uses a novel titanium-based anode (comprising a substrate with a three-dimensional porous structure composed of a titanium dioxide nanotube skeleton and a composite material of SnO2, Sb, and RuO2 coated on the surface of the substrate) to adsorb Cl in a solution. - , producing chlorine gas with strong oxidizing properties and its hydrolysis product HClO, thereby degrading organic pollutants, effectively solving the problem of high concentration of difficult-to-degrade organic matter in electronic wastewater, and then being able to achieve rapid degradation of organic matter, ultimately making the anode have the advantages of long life and high catalytic activity; using a carbon-based material coated with ferroferric oxide as the cathode, the special lattice structure and redox properties of ferroferric oxide are utilized to selectively adsorb heavy metal ions such as copper, zinc and lead. Compared with mainstream carbon-based electrode materials, it can overcome its non-selective problem for multiple ions and improve the adsorption of heavy metal ions (Cu) with relatively low concentrations. 2+ ) adsorption separation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 Schematic diagram of the structure of the electrolytic adsorption device of the present invention; wherein 1 is the water inlet, 2 is the water outlet, 3 is the electrochemical workstation, 4 is the anode, 5 is the cathode, 6 is the wire connecting the positive electrode of the power supply and the anode, and 7 is the wire connecting the negative electrode of the power supply and the cathode;

[0034] Figure 2 Schematic diagram of the preparation process of the cathode in the electrolytic adsorption device of the present invention;

[0035] Figure 3 This is a SEM image of the titanium dioxide nanotube layer on the surface of the anode substrate described in Example 1;

[0036] Figure 4 The adsorption-desorption isotherm and pore size distribution curve of the anode substrate described in Example 1. DETAILED DESCRIPTION

[0037] like Figure 1 As shown, the present invention provides an electrolytic adsorption device, comprising anodes and cathodes alternately arranged in parallel;

[0038] The anode comprises an anode substrate and an anode material coated on the surface of the anode substrate; the anode substrate comprises a titanium foil and a titanium dioxide nanotube layer on the surface of the titanium foil, wherein the titanium dioxide nanotube layer is a three-dimensional array structure; the anode material is a composite material of SnO2, Sb and RuO2;

[0039] The cathode includes a cathode substrate and a cathode material coated on the surface of the cathode substrate. The cathode material is a mixture of carbon-based materials and ferrosoferric oxide.

[0040] In the present invention, unless otherwise specified, all preparation raw materials are commercially available products well known to those skilled in the art.

[0041] In the present invention, the number of repetitions of the alternating parallel arrangement is preferably 3 times (e.g. Figure 3 shown).

[0042] In the present invention, the length of the titanium dioxide nanotubes in the anode substrate is preferably 0.2 to 41 μm, the outer diameter of the titanium dioxide nanotubes is preferably 10 to 100 nm, and the wall thickness of the titanium dioxide nanotubes is preferably 10 to 20 nm.

[0043] In the present invention, the mass ratio of the composite material of SnO2, Sb and RuO2 to the mass ratio of the anode substrate is preferably (1-10): 100. In an embodiment of the present invention, the mass ratio of the composite material of SnO2, Sb and RuO2 to the mass ratio of the anode substrate can be 1:100, 5:100 or 10:100.

[0044] In the present invention, the mass ratio of SnO2, Sb and RuO2 in the composite material of SnO2, Sb and RuO2 is preferably 70:10:20.

[0045] In the present invention, the preparation process of the anode preferably includes the following steps:

[0046] Using titanium foil as a working anode, platinum sheet as a cathode, and a solution containing fluoride ions as an electrolyte, an anodic oxidation reaction is carried out, followed by heat treatment to obtain an anode substrate;

[0047] preparing a precursor solution;

[0048] After the precursor solution is sprayed on the surface of the anode substrate, thermal decomposition is performed to obtain the anode.

[0049] The invention uses titanium foil as a working anode, a platinum sheet as a cathode, and a solution containing fluorine ions as an electrolyte, performs an anodic oxidation reaction, and then performs heat treatment to obtain an anode substrate.

[0050] The present invention does not have any special limitation on the titanium foil and platinum sheet, and any titanium foil and platinum sheet well known to those skilled in the art can be used.

[0051] In the present invention, the concentration of fluoride ions in the fluoride ion-containing solution is preferably 0.2 to 2 mg / L.

[0052] In the present invention, the solute in the electrolyte is preferably ammonium fluoride and / or sodium fluoride. When the solute is ammonium fluoride and sodium fluoride, the present invention does not have any particular restrictions on the ratio of the ammonium fluoride and sodium fluoride, and they can be mixed in any ratio. In an embodiment of the present invention, the solute can be ammonium fluoride.

[0053] In the present invention, the solvent in the electrolyte is preferably one or more of water, dimethyl sulfoxide, and ethylene glycol. When the solvent is two or more of the above-mentioned specific selections, the present invention does not have any particular restrictions on the ratio of the above-mentioned specific substances, and they can be mixed in any ratio. In an embodiment of the present invention, the solvent can be water.

[0054] In the present invention, the voltage of the anodic oxidation reaction is preferably 10 to 30 V, and the time is preferably 2 hours.

[0055] During the anodic oxidation process, fluoride ions react under the influence of an electric field, undergoing a series of chemical reactions with the titanium foil, gradually growing titanium dioxide nanotubes on the surface. By varying the fluoride ion concentration and voltage to influence the reaction rate and path, the present invention can control the three-dimensional structure of the titanium dioxide nanotubes.

[0056] In the present invention, the heat treatment temperature is preferably 400-600°C, and the holding time is preferably 3 hours. In the present invention, the heat treatment is preferably performed in a nitrogen atmosphere. In the present invention, the heat treatment can improve the purity of the electrode material, enhance the stability and density of the material, and improve the electrochemical performance of the material, which is conducive to enhancing the electrode's ability to adsorb heavy metal ions and remove organic matter.

[0057] The method for preparing the anode of the present invention further comprises preparing a precursor solution.

[0058] In the present invention, the solute in the precursor solution preferably includes SnCl4, SbCl3 and RuCl4.

[0059] In the present invention, the solvent in the precursor solution is preferably water.

[0060] In the present invention, the concentration of SnCl4 in the precursor solution is preferably 15 mg / L, the concentration of SbCl3 in the precursor solution is preferably 2.32 mg / L, and the concentration of RuCl4 in the precursor solution is preferably 4.47 mg / L.

[0061] After obtaining the anode substrate and the precursor solution, the present invention sprays the precursor solution on the surface of the anode substrate and then performs thermal decomposition to obtain the anode.

[0062] During the spraying, the temperature of the anode substrate is preferably 300°C. In the present invention, the spraying rate of the precursor solution is preferably 5 psi. In the present invention, the temperature of the thermal decomposition is preferably 500°C, and the time is preferably 10 minutes. In the present invention, the thermal decomposition is preferably carried out in an oxidizing atmosphere.

[0063] After the thermal decomposition is completed, the present invention preferably further comprises sequentially repeating the spraying and thermal decomposition processes. The present invention does not have any particular limitation on the number of repetitions; a number familiar to those skilled in the art may be used, provided that the mass ratio of the anode material on the surface of the anode substrate to the anode substrate meets the aforementioned requirements.

[0064] In the present invention, the cathode substrate is preferably a graphite composite plate. The present invention does not have any special restrictions on the type and composition of the graphite composite plate, and the type and composition well known to those skilled in the art can be used.

[0065] In the present invention, the carbon-based material preferably includes one or more of activated carbon, carbon nanotubes, and carbon black. When the carbon-based material is two or more of the above-mentioned specific selections, the present invention does not have any special restrictions on the ratio of the above-mentioned specific substances, and they can be mixed in any ratio. In an embodiment of the present invention, the carbon-based material can be activated carbon.

[0066] In the present invention, the mass ratio of ferrosoferric oxide to carbon-based material in the cathode material is preferably (2-10): 100. In an embodiment of the present invention, the mass ratio of ferrosoferric oxide to carbon-based material can be 2:100, 5:100 or 10:100.

[0067] like Figure 2As shown, in the present invention, the preparation method of the cathode preferably includes the following steps:

[0068] The cathode is obtained by coating a dispersion containing ferrosoferric oxide and a carbon-based material on the surface of a cathode substrate.

[0069] In the present invention, the concentration of ferrosoferric oxide in the dispersion containing ferrosoferric oxide and carbon-based materials is preferably 0.2 g / L. In the present invention, the mass ratio of ferrosoferric oxide to carbon-based materials in the dispersion containing ferrosoferric oxide and carbon-based materials is preferably (2 to 10): 100. In the present invention, the solvent in the dispersion containing ferrosoferric oxide and carbon-based materials is preferably dimethylformamide (DMF). In the present invention, the dispersion containing ferrosoferric oxide and carbon-based materials also preferably includes a binder; the mass concentration of the binder in the dispersion containing ferrosoferric oxide and carbon-based materials is preferably 5wt%. In the present invention, the binder preferably includes polyvinylidene fluoride (PVDF). In an embodiment of the present invention, the carbon-based material in the dispersion containing ferrosoferric oxide and carbon-based materials is activated carbon.

[0070] In the present invention, the preparation process of the dispersion containing ferrosoferric oxide and the carbon-based material preferably includes: adding the carbon-based material to a solvent and a binder at the same time, adding ferrosoferric oxide, and mixing under stirring. The present invention does not have any particular restrictions on the stirring process, and can be carried out using a process well known to those skilled in the art. In an embodiment of the present invention, the stirring temperature can be room temperature and the stirring time can be 4 hours.

[0071] In the present invention, the coating method is preferably drop coating. The present invention does not have any special limitation on the drop coating process, and the process well known to those skilled in the art can be used.

[0072] After the coating is completed, the present invention also preferably includes drying. The present invention does not have any special restrictions on the drying process, and can be carried out using a process well known to those skilled in the art. In an embodiment of the present invention, the drying is specifically vacuum drying, and the vacuum drying temperature can be 60° C. and the time can be 24 hours.

[0073] In the present invention, the spacing between adjacent anodes and cathodes is preferably 1 cm; the thickness of the anode is preferably 0.5 cm, and the thickness of the cathode is preferably 0.1 cm; the effective area when adjacent anodes and cathodes are arranged in parallel is preferably 10 cm×5 cm.

[0074] In the present invention, the anodes are preferably arranged in series, the cathodes are preferably arranged in series, and a power supply is preferably connected between the anodes and cathodes.

[0075] In the present invention, the anode and cathode are preferably placed in a reactor made of organic glass, with a water outlet provided at the bottom of one side wall of the reactor and a water inlet provided at the top of the other side wall.

[0076] The working principle of the electrolytic adsorption device is as follows: when the anode is connected to the positive electrode of the power supply and the cathode is connected to the negative electrode of the power supply for positive charging, the active sites on the anode surface will adsorb Cl in the solution. - The Cl2 produced and its hydrolysis product HClO have strong oxidizing properties and can degrade organic pollutants, as shown in formulas 1 and 2, where M represents a metal element:

[0077]

[0078] At the same time, heavy metal ions (Cu 2+ 、Zn 2+ 、Ni 2+ etc.) are adsorbed on the cathode surface and enriched;

[0079] When the adsorption is saturated, the anode is connected to the negative electrode of the power supply and the cathode is connected to the positive electrode of the power supply for reverse charging. The previous cathode becomes the anode, so the previously adsorbed heavy metals are desorbed into the concentrated solution, completing resource recovery and electrode regeneration.

[0080] The present invention also provides the use of the electrolytic adsorption device described in the above technical solution in treating chlorine-containing electronic wastewater.

[0081] In the present invention, the method of application preferably comprises the following steps:

[0082] The chlorine-containing electronic wastewater is passed into the electrolytic adsorption device for treatment.

[0083] In the present invention, the COD concentration in the chlorine-containing electronic wastewater is preferably 200 mg / L, the chloride ion concentration is preferably 5 mmol / L, and the Cu 2+ The concentration of ions is preferably 50 mg / L.

[0084] In the present invention, the flow rate of the chlorine-containing electronic wastewater is preferably 0.1 to 2 mL / min, more preferably 0.1 mL / min, 0.5 mL / min or 2 mL / min. In the present invention, the working current of the treatment is preferably 2 to 20 mA / cm 2 , more preferably 2 mA / cm 2 , 5mA / cm 2 , 10mA / cm 2 or 20mA / cm 2 In an embodiment of the present invention, the working current of the treatment can be 5mA / cm 2 .

[0085] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions of the present invention. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0086] Example 1

[0087] Titanium foil was used as a working anode, a platinum tail was used as a cathode, and an ethylene glycol aqueous solution containing ammonium fluoride (fluoride ion concentration was 2 mg / L, and the volume ratio of ethylene glycol to water was 30:70) was used as an electrolyte. After an anodic oxidation reaction (voltage was 20 V, time was 2 h), a heat treatment was performed under an inert atmosphere and 400° C. to obtain an anode substrate (including titanium foil and a titanium dioxide nanotube layer formed on the surface of the titanium foil, the titanium dioxide nanotube layer was a three-dimensional porous structure, the titanium dioxide nanotube had a length of 1 to 41 μm, an outer diameter of 10 to 100 nm, and a wall thickness of 10 to 20 nm), and the anode specific surface area was about 28.155 m 2 / g;

[0088] SnCl4, SbCl3, RuCl4 and water were mixed to obtain a mixed solution (wherein the concentration of SnCl4 was 15 mg / L, the concentration of SbCl3 was 2.32 mg / L, the concentration of RuCl4 was 4.47 mg / L, and the mass ratio of SnO2, Sb and RuO2 was 70:10:20);

[0089] After spraying 10 mL of the mixed solution on the surface of a titanium foil at a temperature of 300° C. at a speed of 5 psi, the mixture was placed in a muffle furnace and thermally decomposed at 500° C. in an oxidizing atmosphere for 10 min. The above spraying and sintering processes were repeated 5 times to obtain an anode (with a thickness of approximately 0.5 cm, including an anode substrate and a composite material of SnO2, Sb and RuO2 on the surface of the anode substrate; the mass ratio of the composite material of SnO2, Sb and RuO2 to the mass of the anode substrate is approximately 1:100);

[0090] Using a graphite composite plate as a cathode substrate, activated carbon was added to dimethylformamide and polyvinylidene fluoride was added, followed by ferroferric oxide. The mixture was stirred at room temperature for 4 hours to obtain a dispersion containing ferroferric oxide and activated carbon (the concentration of ferroferric oxide was 0.2 g / L, the concentration of activated carbon was 10 g / L, and the concentration of polyvinylidene fluoride was 5 wt%).

[0091] The dispersion containing ferrosoferric oxide and activated carbon is evenly coated on the surface of the graphite composite plate, and placed in a vacuum drying oven at 60° C. for 24 h to obtain a cathode (with a thickness of 0.1 cm);

[0092] The anodes and cathodes are stacked and repeatedly arranged in sequence, wherein the number of repetitions is 3 times, the spacing between adjacent anodes and cathodes is 1 cm, and the effective contact area of adjacent anodes and cathodes when arranged in parallel is 10 cm×5 cm; the anodes are arranged in series, and the cathodes are arranged in series, and a power supply is connected between the anodes and cathodes, and they are placed in a reactor made of organic glass, wherein a water inlet is provided at the bottom of the side wall of one side of the reactor, and a water outlet is provided at the top of the side wall of the other side, to obtain;

[0093] Figure 3 is the SEM image of the titanium dioxide nanotube layer, wherein a is a top view of the nanotube array (magnified 15000 times), b is a side view of the nanotube array (magnified 30000 times), Figure 3 It can be seen that the titanium dioxide nanotube layer is a three-dimensional array structure;

[0094] Figure 4 is the adsorption-desorption isotherm and pore size distribution curve of the anode substrate, Figure 4 It can be seen from the adsorption isotherm that the adsorption amount gradually increases with the increase of relative pressure; when the relative pressure is low, the adsorption amount increases relatively slowly; when the relative pressure is close to 1, the adsorption amount increases rapidly; from the desorption isotherm, it can be seen that the trend of the desorption process is similar to that of the adsorption process, but when the relative pressure is high, the desorption curve does not coincide with the adsorption curve, indicating that there is a mesoporous structure in the material; Figure 4 The pore size distribution curve in the figure is obtained by analyzing and calculating the adsorption-desorption isotherm, which further reveals the detailed information of the pore structure of the anode substrate, that is, the number of pores with a pore size of about 20 nm is relatively large, and their contribution to the pore volume is large; in the area with a pore size less than 20 nm, the curve rises rapidly, indicating that pores with smaller pore sizes also have a certain distribution, but the number is relatively small; when the pore size is greater than 20 nm, the curve gradually decreases, indicating that the number of pores gradually decreases with the increase of the pore size.

[0095] Example 2

[0096] Refer to Example 1, except that the concentration of fluoride ions in the ethylene glycol aqueous solution containing ammonium fluoride is 0.2 mg / L.

[0097] Example 3

[0098] Refer to Example 1, except that the concentration of fluoride ions in the ethylene glycol aqueous solution containing ammonium fluoride is 1 mg / L.

[0099] Example 4

[0100] Refer to Example 1, except that the voltage of the anodic oxidation reaction is 10V.

[0101] Example 5

[0102] Refer to Example 1, except that the voltage of the anodic oxidation reaction is 30V.

[0103] Example 6

[0104] Refer to Example 1, except that, after the oxidation reaction is completed, heat treatment is performed under an inert atmosphere at 500°C.

[0105] Example 7

[0106] Refer to Example 1, except that, after the oxidation reaction is completed, heat treatment is performed under an inert atmosphere at 600°C.

[0107] Example 8

[0108] Refer to Example 1, except that the mass ratio of the composite material of SnO2, Sb and RuO2 in the anode to the mass ratio of the anode substrate is 5:100).

[0109] Example 9

[0110] Refer to Example 1, except that the mass ratio of the composite material of SnO2, Sb and RuO2 in the anode to the mass ratio of the anode substrate is 10:100).

[0111] Example 10

[0112] Refer to Example 1, except that the mass ratio of ferrosoferric oxide to activated carbon in the dispersion containing ferrosoferric oxide and activated carbon is 4:100.

[0113] Example 11

[0114] Refer to Example 1, except that the mass ratio of ferrosoferric oxide to activated carbon in the dispersion containing ferrosoferric oxide and activated carbon is 6:100.

[0115] Example 12

[0116] Refer to Example 1, except that the mass ratio of ferrosoferric oxide to activated carbon in the dispersion containing ferrosoferric oxide and activated carbon is 10:100.

[0117] Comparative Example 1

[0118] Refer to Example 1, except that pure titanium foil is used as the anode.

[0119] Comparative Example 2

[0120] Refer to Example 1, except that the amount of ferrosoferric oxide added during the cathode preparation process is 0.

[0121] Application Examples 1-3

[0122] Chlorine-containing electronic wastewater (COD concentration of 200 mg / mL, copper ion concentration of 50 mg / L, chloride ion concentration of 5 mmol / mL) was introduced into the chlorine-containing electronic wastewater described in Examples 1 to 13 and Comparative Examples 1 to 2 at a flow rate of 0.1 mL / s (Application Example 1), 0.5 mL / s (Application Example 2), or 2 mL / s (Application Example 3) for treatment (the working current of the treatment was 5 mA / cm 2 ), the effect data after treatment are shown in Tables 1 to 3:

[0123] Table 1 Test results of application example 1

[0124]

[0125]

[0126] Table 2 Test results of application example 2

[0127]

[0128]

[0129] Table 3 Test results of application example 3

[0130]

[0131] It can be seen from Tables 1 to 3 that the electrolytic adsorption devices described in the present invention can effectively adsorb and remove pollutants such as copper, COD and chloride ions. Chlorine-containing electronic wastewater often contains organic matter and heavy metals at the same time. It is recommended to give priority to the optimized conditions of Example 1 or Example 9. The difference is not large, and the overall effect is better than other working conditions. When the water flow rate is 0.5mL / min, the removal rate of the above pollutants is relatively high, especially the current efficiency is high. When the water flow rate rises to 2mL / min, the removal rate decreases. In addition, the content of the coating on the anode surface and the ferroferric oxide content on the cathode surface have a greater influence on the removal of the corresponding pollutants. Within the scope of this experiment, the higher the content, the higher the removal rate.

[0132] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation thereto. It should be noted that those skilled in the art may make various improvements and modifications without departing from the principles of the present invention, and such improvements and modifications shall also be considered within the scope of protection of the present invention.

Claims

1. An electrolytic adsorption device, characterized in that: comprising anodes and cathodes arranged alternately in parallel; The anode comprises an anode substrate and an anode material coated on the surface of the anode substrate; the anode substrate comprises a titanium foil and a titanium dioxide nanotube layer on the surface of the titanium foil, wherein the titanium dioxide nanotube layer is a three-dimensional array structure; the anode material is a composite material of SnO2, Sb and RuO2; The cathode includes a cathode substrate and a cathode material coated on the surface of the cathode substrate. The cathode material is a mixture of carbon-based materials and ferrosoferric oxide.

2. The electrolytic adsorption device according to claim 1, characterized in that: The alternating parallel arrangement is repeated three times.

3. The electrolytic adsorption device according to claim 1, wherein: The mass ratio of the anode material to the anode substrate is (1-10):100; The titanium dioxide nanotubes in the anode substrate have a length of 0.2 to 41 μm, an outer diameter of 10 to 100 nm, and a wall thickness of 10 to 20 nm.

4. The electrolytic adsorption device according to claim 3, characterized in that: The mass ratio of SnO2, Sb and RuO2 in the composite material of SnO2, Sb and RuO2 is 70:10:

20.

5. The electrolytic adsorption device according to any one of claims 1 to 4, characterized in that: The preparation process of the anode comprises the following steps: Using titanium foil as a working anode, platinum sheet as a cathode, and a solution containing fluoride ions as an electrolyte, an anodic oxidation reaction is carried out, followed by heat treatment to obtain an anode substrate; preparing a precursor solution; After the precursor solution is sprayed on the surface of the anode substrate, thermal decomposition is performed to obtain the anode.

6. The electrolytic adsorption device according to claim 5, characterized in that: The concentration of fluoride ions in the electrolyte is 0.2 to 2 mg / L; The voltage of the anodic oxidation reaction is 10 to 30 V, and the time is 2 hours; The heat treatment temperature is 400-600° C., and the heat preservation time is 3 hours.

7. The electrolytic adsorption device according to claim 1, characterized in that: The mass ratio of the carbon-based material to ferrosoferric oxide in the cathode material is 100:(2-10); The carbon-based material includes one or more of activated carbon, carbon nanotubes and carbon black.

8. The electrolytic adsorption device according to claim 1 or 7, characterized in that: The cathode preparation process comprises the following steps: The cathode is obtained by coating a dispersion containing ferrosoferric oxide and a carbon-based material on the surface of a cathode substrate.

9. Use of the electrolytic adsorption device according to any one of claims 1 to 8 in treating chlorine-containing electronic wastewater, characterized in that: The method of application comprises the following steps: The chlorine-containing electronic wastewater is passed into the electrolytic adsorption device for treatment.

10. The use according to claim 9, characterized in that The flow rate of the chlorine-containing electronic wastewater is 0.1 to 2 mL / min; The working current of the treatment is 2-20 mA / cm 2 , the voltage is 2V.

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