A treatment device for removing harmful ions in contaminated liquid and a treatment method thereof

Abstract

The application relates to the technical field of pollution treatment, and particularly discloses a treatment device for removing harmful ions in polluted liquid and a treatment method thereof. The treatment method for removing harmful ions in polluted liquid is used for performing electrodialysis adsorption treatment on the polluted liquid; the electrodialysis adsorption treatment is performed in at least one unit cell arranged between an anode and a cathode, the unit cell comprises a blocking chamber, the blocking chamber divides the unit cell into a receiving chamber and a feed liquid chamber, the feed liquid chamber is electrically connected with the anode or the cathode, the receiving chamber is electrically connected with the anode or the cathode, the anode and the cathode are made of porous electrode materials, the receiving chamber is provided with receiving liquid, the feed liquid chamber is provided with waste liquid to be treated, and the blocking chamber is filled with a blocking material and a buffer solution. The treatment method for removing harmful ions in polluted liquid has the advantages of good treatment effect and low operation cost.

Description

Technical Field

[0001] This application relates to the field of harmful ion treatment technology in polluted liquids, and more specifically, it relates to a treatment device and method for removing harmful ions from polluted liquids. Background Technology

[0002] Water pollution generally refers to the polluted liquid formed after harmful pollutants enter water bodies. The types of polluted liquids are very complex, including urban sewage, industrial and agricultural wastewater, and natural environmental wastewater. Harmful pollutants in polluted liquids can be divided into ionic and non-ionic types. Non-ionic harmful pollutants can be reduced in concentration or even eliminated from water bodies through physical and biological self-purification. Ionic harmful pollutants include heavy metal ions, nitrogen ions, phosphorus ions, cyanide ions, and halide ions. Due to their small ionic radii, ionic harmful pollutants migrate very easily, making their removal more difficult.

[0003] Currently, technicians employ various treatment methods, including adsorption, complexation, enrichment, and filtration. Adsorption uses materials such as chitosan and sepiolite for adsorption, but this method is slow and unsuitable for treating large volumes of contaminated liquid. Complexation involves adding organic or inorganic complexing agents to the contaminated liquid to form complexes with harmful ions; this method is costly. Enrichment relies on plants to absorb and concentrate harmful ions, but the treatment cycle is long and the results are slow. Filtration separates harmful ions using nanofiltration membranes or ion exchange membranes; this method is costly and can only handle a limited number of types of harmful ions.

[0004] The above-mentioned treatment methods all have certain limitations and cannot efficiently and cost-effectively remove harmful ions from polluted liquids. Summary of the Invention

[0005] In order to efficiently and cost-effectively remove harmful ions from contaminated liquids, this application provides a treatment device and method for removing harmful ions from contaminated liquids.

[0006] In a first aspect, this application provides a treatment device for removing harmful ions from contaminated liquid, employing the following technical solution:

[0007] A treatment device for removing harmful ions from polluted liquid includes at least one unit tank disposed between an anode and a cathode. The unit tank includes a barrier chamber that divides the unit tank into a receiving chamber and a feed chamber. The feed chamber is electrically connected to the anode or cathode, and the receiving chamber is electrically connected to the anode or cathode. The anode and cathode are made of porous electrode material.

[0008] The receiving chamber contains receiving liquid, the feed liquid chamber contains contaminated liquid, and the barrier chamber is filled with barrier material and buffer solution.

[0009] By adopting the above technical solution, the size of the unit tank is designed according to the amount of polluted liquid. Barrier material and buffer solution are filled into the barrier chamber, and then the polluted liquid to be treated is added to the feed chamber, and receiving liquid is added to the receiving chamber. If the harmful ions are cations, the anode is placed in the feed chamber and the cathode in the receiving chamber; otherwise, the cathode is placed in the feed chamber and the anode in the receiving chamber. The anode and cathode are connected to a DC power supply. After applying a low-voltage DC current, a current is formed between the receiving chamber and the feed chamber. Driven by the electric field, the harmful ions in the feed chamber migrate towards the receiving chamber. Then, the harmful ions enter the barrier chamber and are trapped by the barrier material. Over time, most of the harmful ions accumulate in the barrier chamber, while a small portion migrates to the receiving chamber, thus completing the removal of the harmful ions. This method has high efficiency and low treatment cost.

[0010] Secondly, this application provides a method for removing harmful ions from contaminated liquid, employing the following technical solution:

[0011] A method for removing harmful ions from polluted liquid involves electrodialysis adsorption treatment of the polluted liquid.

[0012] The electrodialysis adsorption treatment is carried out in a unit cell containing at least one anode and cathode. The unit cell includes a barrier chamber that divides the unit cell into a receiving chamber and a feed chamber. The feed chamber is electrically connected to the anode or cathode, and the receiving chamber is electrically connected to the anode or cathode. The anode and cathode are made of porous electrode material.

[0013] The receiving chamber is equipped with receiving liquid;

[0014] The liquid feed chamber contains waste liquid to be treated;

[0015] The barrier chamber is filled with barrier material and buffer solution, wherein the barrier material is one or more of biomass material, inorganic particulate material, and synthetic polymer material.

[0016] By adopting the above technical solution, when treating polluted liquid by electrodialysis, harmful ions first enter the barrier chamber from the feed chamber. The barrier material and the buffer solution form a membrane-like barrier adsorption layer. On the one hand, the barrier adsorption layer can play a role in shielding the migration of substances and suppressing the free diffusion effect caused by the concentration difference on both sides of the barrier chamber during the treatment process, thereby reducing the exchange of substances between the receiving chamber and the feed chamber and ensuring the normal operation of the electrodialysis adsorption treatment process.

[0017] On the other hand, the barrier material within the adsorption layer can effectively adsorb and enrich harmful ions. This enrichment effect is crucial when treating large quantities of low-concentration polluted liquid, enabling stable operation under low current conditions for extended periods, continuously absorbing harmful ions and minimizing the amount of harmful ions entering the receiving chamber. Furthermore, when the barrier material reaches saturation, it can be directly replaced, and the adsorbed barrier material can undergo further harmless treatment. Compared to traditional anion-cation selective permeation membranes, biomass materials, inorganic particulate materials, and synthetic polymer materials are widely available and inexpensive. Therefore, the treatment method described in this application offers lower treatment costs and better treatment results.

[0018] Furthermore, the anode and cathode of this application are made of porous electrode material with a high specific surface area. This supercapacitor-type electrode material can form a double electric layer structure on the surface of the anode and cathode, which plays a very good protective role for the electrodes and maintains a stable current intensity for a long time. It has a very good treatment effect on polluted liquids of different concentrations.

[0019] Preferably, the biomass material is one or more selected from sugarcane bagasse, corn grits, coconut shell, rice bran, wheat bran, sawdust, gelatin, and chitosan. All the biomass materials listed in this application can achieve the corresponding technical effects. Based on the ease of obtaining the materials and their cost, a further preferred biomass material is one selected from coconut shell, wheat bran, and sawdust.

[0020] By adopting the above technical solutions, biomass materials are widely available in nature, diverse in type, easy to obtain, and very low in cost. Furthermore, biomass materials contain a large number of active groups such as hydroxyl, carboxyl, and amino groups, exhibiting high adsorption and chelation capabilities. This reduces the migration of harmful ions enriched within the barrier adsorption layer to the receiving chamber, ensuring that more harmful ions are efficiently retained by the barrier adsorption layer. Simultaneously, it provides a stable electrochemical working environment for the anode or cathode within the receiving chamber.

[0021] Preferably, the inorganic particulate material is one or more of the following: sandy soil, clay soil, loam, mica powder, talc powder, montmorillonite powder, kaolinite powder, wollastonite powder, borosilicate mineral particles, carbonate mineral particles, and sulfate mineral particles.

[0022] The inorganic particulate materials listed in this application can all achieve the corresponding technical effects. Based on the wide availability and cost of the materials, the inorganic particulate material is preferably loam.

[0023] By adopting the above technical solution and selecting inorganic particulate materials as the isolation material, the smaller particle size and higher packing density of the inorganic particles enable the formation of a denser adsorption isolation layer, further reducing the migration of harmful ions into the receiving chamber. Furthermore, the colloid-like substance formed between the inorganic particles and the buffer solution can effectively adsorb some harmful ions, which are bound to the crystal faces or lattices of the inorganic minerals, making migration difficult. Moreover, under the influence of an electric field, the electromotive force of the inorganic particulate colloid changes, which is conducive to the formation of insoluble compounds by harmful ions, which are then fixed and enriched within the isolation adsorption layer, further improving the treatment effect.

[0024] Furthermore, various biomass materials, inorganic particulate materials, and synthetic polymer materials, as well as combinations thereof, can achieve corresponding technical effects in this application. Compared to biomass materials and inorganic particulate materials, synthetic polymer materials such as molecular sieves, resin microspheres, rubber microspheres, and synthetic fiber powders have higher processing costs. Therefore, this application preferably uses a combination of biomass materials and inorganic particulate materials. Furthermore, this application preferably uses a barrier material composed of coconut shell powder and soil in a mass ratio of 1:3.

[0025] Preferably, the porous electrode material is one or more selected from conductive activated carbon, mesoporous carbon, carbon fiber, carbon nanotubes, and carbon aerogel. More preferably, all the porous electrode materials listed in this application can achieve the corresponding technical effects; in this application, conductive activated carbon is the preferred porous electrode material.

[0026] In a further preferred embodiment, the anode and cathode in this application are composed of a conductive mesh, an adhesive, and a porous electrode material.

[0027] In a further preferred embodiment, the method for preparing the anode and cathode of this application includes: mixing porous electrode material with binder carbon and a small amount of dispersant to form a conductive slurry, and then bonding it to a conductive mesh to form an electrode.

[0028] More preferably, the conductive mesh is one of nickel mesh, iron mesh, copper mesh, stainless steel mesh or aluminum mesh.

[0029] Further preferred, the porous electrode material is conductive activated carbon, which is composed of commercial activated carbon and commercial conductive carbon.

[0030] More preferably, in the conductive slurry, the mass ratio of commercial activated carbon is 30-90%, the mass ratio of commercial conductive carbon is 5-60%, and the mass ratio of binder is 5-30%.

[0031] More preferably, the binder comprises at least one organic phase binder selected from polyvinylidene fluoride, polytetrafluoroethylene, Nafion, and polyvinylidene fluoride-hexafluoropropylene copolymer. The dispersant is one of N-methylpyrrolidone, ethanol, and water.

[0032] By adopting the above technical solutions and optimizing and adjusting the composition of porous electrode materials, carbon porous electrode materials have higher specific surface area and pore volume, are relatively inexpensive, have good physicochemical stability, and excellent electrochemical performance, further extending the effective processing time under higher current intensities.

[0033] Preferably, the specific surface area of ​​the porous electrode material is greater than 200 m² / g.

[0034] By adopting the above technical solutions, the specific surface area of ​​porous electrode materials is tested and adjusted to enhance the double-layer effect of the anode or cathode, improve the reversible adsorption of harmful ions on the surface of the active material of the porous electrode, further extend the effective treatment time of the electrode, and obtain better treatment results.

[0035] Preferably, in the electrodialysis adsorption treatment, the voltage is 0.5-24V.

[0036] By employing the above technical solutions, excessive voltage increases the migration rate of harmful ions from the isolation adsorption layer into the receiving chamber, also increasing long-term operating costs. Furthermore, high voltage can cause water molecules to dissociate, forming oxygen and hydrogen, which can be dangerous. Insufficient voltage reduces the migration rate of harmful ions into the isolation adsorption layer, resulting in lower treatment efficiency. Optimizing and adjusting the voltage intensity can improve the migration rate of harmful ions under lower current conditions, balancing the adsorption and desorption of harmful ions within the isolation adsorption layer and improving the overall treatment effect.

[0037] Preferably, the thickness of the barrier chamber is 3-10 cm.

[0038] More preferably, when biomass materials, inorganic particulate materials, and synthetic polymer materials are selected as barrier materials, the total porosity of the barrier chamber is 20%-80%. More preferably, when soil materials and their composite materials are selected as barrier materials, the total porosity of the barrier chamber is 30%-60%.

[0039] By adopting the above technical solutions, a thicker barrier chamber provides better isolation, but it reduces the mass transfer efficiency and current density between the receiving chamber and the feed chamber. A thinner barrier chamber has a higher mass transfer rate, but its adsorption and enrichment effect on harmful ions is worse, and the concentration gradient free diffusion of harmful ions is enhanced. Therefore, optimizing and adjusting the thickness of the barrier chamber, along with adjusting the total porosity within the barrier chamber, further enhances the treatment effect on harmful ions in the contaminated liquid.

[0040] Preferably, the mass ratio of the barrier material to the buffer solution is (60-80):1.

[0041] By adopting the above technical solution, the mass ratio of barrier material to buffer solution was tested and screened to further balance the conductivity and adsorption performance of the barrier adsorption layer, thereby obtaining a better comprehensive treatment effect.

[0042] Preferably, the buffer solution is one of a carbonate buffer solution, a phosphate buffer solution, or a citrate system.

[0043] By adopting the above technical solution, the buffer solution increases the ion concentration within the isolation adsorption layer, improves conductivity, enhances the intensity of the processing current, and maintains the charge balance on both sides of the isolation chamber. Furthermore, the buffer solution can regulate the pH value within the isolation adsorption layer, improve the charge density on the surface of the barrier material particles, which is beneficial for increasing the adsorption force between harmful ions and the barrier material, thereby increasing the enrichment of harmful ions by the barrier adsorption layer.

[0044] In summary, this application has the following beneficial effects:

[0045] 1. This application incorporates a barrier chamber within the unit tank, filled with barrier material and buffer solution to form a barrier adsorption layer. A DC electric field is then applied to both sides of the barrier chamber. Under the influence of the electric field, harmful ions migrate from the feed chamber to the receiving chamber, where they are adsorbed and enriched by the barrier material. This allows for the maintenance of a high current intensity over a relatively long period, resulting in excellent treatment of low-concentration contaminated liquids. Furthermore, the enriched barrier material can be promptly replaced for further treatment. Additionally, biomass materials and inorganic granular materials are widely available and inexpensive, making them highly suitable for industrial applications.

[0046] 2. In this application, carbon material is preferred as the porous electrode material. The specific surface area, current intensity, type of buffer solution, and thickness of the barrier chamber of the porous electrode material are optimized and adjusted to further improve the enrichment of the barrier adsorption layer and enhance the treatment effect on the polluted liquid.

[0047] 3. The treatment method for removing harmful ions from polluted liquid using the method described in this application has a high treatment effect and a low treatment cost. Attached Figure Description

[0048] Figure 1 : Schematic diagram of the treatment device for removing harmful ions from polluted liquid in Embodiment 1 of this application.

[0049] Figure 2 : Schematic diagram of the treatment device for removing harmful ions from polluted liquid in Embodiment 2 of this application.

[0050] Figure 3 It curves of the treatment methods for removing harmful ions from polluted liquids in Examples 1-6 and Comparative Examples 1-5 of this application.

[0051] Figure 4 The diagram shows the treatment effect of the method for removing harmful ions from polluted liquid according to Example 1 of this application.

[0052] Figure 5 The treatment effect diagram of the method for removing harmful ions from polluted liquid according to Example 2 of this application. Detailed Implementation

[0053] The present application will be further described in detail below with reference to the embodiments.

[0054] Unless otherwise specified, the raw materials used in the embodiments and comparative examples of this application are all commercially available. Example

[0055] Example 1

[0056] Reference Figure 1 The treatment device for removing harmful ions from polluted liquid in this embodiment includes a unit pool disposed between the anode and the cathode. The unit pool is a box-shaped container made of PE plastic, and the dimensions of the unit pool are 30cm×20cm×15cm.

[0057] The unit tank has a central baffle chamber that divides it into a receiving chamber and a feed chamber. The feed chamber contains the wastewater to be treated, while the receiving chamber contains the receiving liquid, which is a citric acid-sodium citrate system with a pH between 6.5 and 7.5. The polluted liquid is diluted chromium-contaminated wastewater with a chromium ion concentration of 0.05 mol / L. The receiving chamber is electrically connected to the cathode, and the feed chamber is electrically connected to the anode.

[0058] The barrier chamber includes two supporting mesh panels, two barrier fabrics, barrier material, and a buffer solution. The two supporting mesh panels are arranged parallel to each other and opposite to each other, with a distance of 6 cm between them. The two barrier fabrics are respectively attached to the opposite inner surfaces of the two supporting mesh panels. In this embodiment, the barrier fabric is made of polyester.

[0059] Barrier material and buffer solution are filled into the gap between two support mesh plates to form a barrier adsorption layer. The support mesh plates and barrier cloth play a supporting and barrier role, preventing solid particles of the barrier material from entering the receiving chamber and the feed liquid chamber.

[0060] In this embodiment, the anode and cathode are composed of a conductive mesh, a binder, and a porous electrode material. During preparation, the binder, dispersant, porous electrode material and a small amount of dispersant are mixed to form a conductive slurry. The conductive slurry is then coated and bonded to the conductive mesh. After drying, the electrode is formed and then cut to a suitable size to obtain the anode or cathode.

[0061] The porous electrode material in this embodiment is conductive activated carbon with a specific surface area of ​​300 m² / g. The conductive activated carbon is composed of commercial activated carbon and commercial conductive carbon.

[0062] The conductive paste of this embodiment comprises the following components by mass fraction: 60% commercial activated carbon, 30% commercial conductive carbon, and 10% binder. The binder is polyvinylidene fluoride binder. The dispersant is ethanol.

[0063] The method for removing harmful ions from polluted liquid in this embodiment uses the above-mentioned treatment device to perform electrodialysis adsorption treatment on the polluted liquid.

[0064] The barrier material is loam. The total porosity of the barrier adsorption layer is 30%. The buffer solution is a sodium dihydrogen phosphate-disodium hydrogen phosphate system with a pH value between 6.5 and 7.5. The voltage is 1.2V. The mass ratio of the barrier material to the buffer solution is 70:1.

[0065] Example 2

[0066] Reference Figure 2 The treatment device for removing harmful ions from polluted liquid in this embodiment includes a unit pool disposed between the anode and the cathode. The unit pool is a box-shaped container made of PE plastic, and the dimensions of the unit pool are 30cm×20cm×15cm.

[0067] The unit tank has a central baffle chamber that divides it into a receiving chamber and a feed chamber. The feed chamber contains contaminated liquid, and the receiving chamber contains receiving liquid, which is a 0.5% sodium sulfate solution. The contaminated liquid is diluted chromium-contaminated wastewater with a chromium ion concentration of 0.05 mol / L. The receiving chamber is electrically connected to the cathode, and the feed chamber is electrically connected to the anode.

[0068] The barrier chamber includes two supporting mesh panels, two barrier fabrics, barrier material, and a buffer solution. The two supporting mesh panels are arranged parallel to each other and opposite to each other, with a distance of 3 cm between them. The two barrier fabrics are respectively attached to the opposite inner surfaces of the two supporting mesh panels. In this embodiment, the barrier fabric is made of polyester.

[0069] Barrier material and buffer solution are filled into the gap between two support mesh plates to form a barrier adsorption layer. The support mesh plates and barrier cloth play a supporting and barrier role, preventing solid particles of the barrier material from entering the receiving chamber and the feed liquid chamber.

[0070] In this embodiment, the anode and cathode are composed of a conductive mesh, a binder, and a porous electrode material. During preparation, the binder, the porous electrode material, and a small amount of dispersant are mixed to form a conductive slurry. The conductive slurry is then coated and bonded to the conductive mesh to form an electrode, which is then cut to a suitable size to obtain the anode or cathode.

[0071] The porous electrode material in this embodiment is carbon aerogel with a specific surface area of ​​500 m² / g. The conductive activated carbon is composed of carbon aerogel and commercial conductive carbon.

[0072] The conductive paste of this embodiment comprises the following components by mass fraction: 60% carbon aerogel, 30% commercial conductive carbon, and 10% binder. The binder is a polytetrafluoroethylene binder. The dispersant is N-methylpyrrolidone.

[0073] The method for removing harmful ions from polluted liquid in this embodiment uses the above-mentioned treatment device to perform electrodialysis adsorption treatment on the polluted liquid.

[0074] The barrier material is loam. The total porosity of the barrier adsorption layer is 60%. The buffer solution is a sodium bicarbonate-sodium hydroxide system with a pH between 6.5 and 7.5. The voltage is in the range of 0.5V. The mass ratio of the barrier material to the buffer solution is 60:1.

[0075] Example 3

[0076] The treatment device for removing harmful ions from polluted liquid in this embodiment includes a unit pool disposed between the anode and the cathode. The unit pool is a box-shaped container made of PE plastic, and the dimensions of the unit pool are 30cm×20cm×15cm.

[0077] The unit tank has a central baffle chamber that divides it into a receiving chamber and a feed chamber. The feed chamber circulates polluted liquid, while the receiving chamber circulates buffer solution. The polluted liquid is diluted chromium-contaminated wastewater with a chromium ion concentration of 0.05 mol / L. The receiving solution is a 1% sodium chloride solution. The receiving chamber is electrically connected to the cathode, and the feed chamber is electrically connected to the anode.

[0078] The barrier chamber includes two supporting mesh panels, two barrier fabrics, barrier material, and a buffer solution. The two supporting mesh panels are arranged parallel to each other and opposite to each other, with a distance of 10cm between them. The two barrier fabrics are respectively attached to the opposite inner surfaces of the two supporting mesh panels. In this embodiment, the barrier fabric is made of polyester.

[0079] Barrier material and buffer solution are filled into the gap between two support mesh plates to form a barrier adsorption layer. The support mesh plates and barrier cloth play a supporting and barrier role, preventing solid particles of the barrier material from entering the receiving chamber and the feed liquid chamber.

[0080] In this embodiment, the anode and cathode are composed of a conductive mesh, a binder, and a porous electrode material. During preparation, the binder, the porous electrode material, and a small amount of dispersant are mixed to form a conductive slurry. The conductive slurry is then coated and bonded to the conductive mesh to form an electrode, which is then cut to a suitable size to obtain the anode or cathode.

[0081] The porous electrode material in this embodiment is mesoporous carbon with a specific surface area of ​​100 m² / g. The conductive activated carbon is composed of mesoporous carbon and commercial conductive carbon.

[0082] The conductive paste of this embodiment comprises the following components by mass fraction: 60% mesoporous carbon, 30% commercial conductive carbon, and 10% binder. The binder is polyvinylidene fluoride binder. The dispersant is N-methylpyrrolidone.

[0083] The method for removing harmful ions from polluted liquid in this embodiment uses the above-mentioned treatment device to perform electrodialysis adsorption treatment on the polluted liquid.

[0084] The barrier material is loam. The total porosity of the barrier adsorption layer is 20%. The buffer solution is a sodium bicarbonate-sodium hydroxide system with a pH between 6.5 and 7.5. The voltage is 24V. The mass ratio of the barrier material to the buffer solution is 80:1.

[0085] Example 4

[0086] The difference between the treatment device and treatment method for removing harmful ions from polluted liquid in this embodiment and that in embodiment 1 is that the barrier material in the barrier chamber is sawdust, while the rest is the same as in embodiment 1.

[0087] Example 5

[0088] The difference between the treatment device and treatment method for removing harmful ions from polluted liquid in this embodiment and that in embodiment 1 is that the barrier material in the barrier chamber is composed of coconut shell powder and wheat bran in a mass ratio of 1:3, and the rest is the same as in embodiment 1.

[0089] Example 6

[0090] The difference between the treatment device and treatment method for removing harmful ions from polluted liquid in this embodiment and that in embodiment 1 is that the barrier material in the barrier chamber is composed of coconut shell powder and soil in a mass ratio of 1:3, and the rest is the same as in embodiment 1.

[0091] Comparative Example

[0092] Comparative Example 1

[0093] The difference between the treatment device and method for removing harmful ions from the polluted liquid in this comparative example and Example 1 is that a cation permeable membrane is used instead of a barrier chamber, and the polluted liquid is chromium-polluted waste liquid with a chromium ion concentration of 0.3 mol / L. The rest is the same as in Example 1.

[0094] Comparative Example 2

[0095] The difference between the treatment device and method for removing harmful ions from the polluted liquid in this comparative example and Example 1 is that a cation permeable membrane is used instead of a barrier chamber, while the rest is the same as in Example 1.

[0096] Comparative Example 3

[0097] The difference between the treatment device and method for removing harmful ions from polluted liquid in this comparative example and Example 1 is that a common carbon electrode is used instead of a porous electrode material electrode, while the rest is the same as in Example 1.

[0098] Comparative Example 4

[0099] The difference between the treatment device and method for removing harmful ions from the polluted liquid in this comparative example and Example 1 is that the distance between the two supporting mesh plates in the barrier chamber is 1 cm, while the rest is the same as in Example 1.

[0100] Comparative Example 5

[0101] The difference between the treatment device and method for removing harmful ions from the polluted liquid in this comparative example and Example 1 is that the barrier material is glass microspheres, while the rest is the same as in Example 1.

[0102] Performance testing

[0103] Detection methods

[0104] Electrochemical tests and treatment effect tests were conducted according to the treatment methods for removing harmful ions in Examples 1-6 and Comparative Examples 1-5. The test results are as follows: Figure 3 , Figure 4 , Figure 5 As shown.

[0105] Analyze Examples 1-3 and Comparative Examples 1-2 in conjunction with Figure 3 It can be seen that when using a conventional cation permeation membrane as the primary barrier separator, under high-concentration contaminated liquid conditions, the initial current intensity is very high, the migration rate of harmful ions is very high, and the concentration of harmful ions in the receiving chamber rises sharply. Although it can reduce the concentration of harmful ions in the feed liquid chamber relatively quickly, the high concentration of harmful ions will seriously affect the electrodes, causing the electrode material to deactivate rapidly, resulting in a sharp drop in current intensity to a very low level within a short time or even a few minutes. Furthermore, when treating low-concentration contaminated liquids, the conventional cation permeation membrane exhibits very low current intensity, low overall current efficiency, and poor treatment effect.

[0106] In addition, combined Figure 3 As can be seen, this application uses barrier materials and buffer solutions to form a barrier adsorption layer. When treating low-concentration polluted liquids, it can maintain a relatively stable current intensity for more than 100 hours, continuously adsorbing and enriching harmful ions, reducing the impact of harmful ions in the receiving room on the electrodes, and exhibiting excellent treatment effects on low-concentration polluted liquids. Simultaneously, the barrier materials are made of biomass or inorganic granular materials, which are inexpensive and readily available, resulting in low treatment costs. Combined with... Figure 4 , Figure 5As can be seen, after 9 days of treatment in Example 1, the contaminated liquid in the feed chamber returned to clarity, and chromium ions were basically removed. The receiving chamber also maintained good clarity, with chromium ions almost entirely adsorbed and enriched within the barrier adsorption layer, demonstrating excellent treatment results. In Example 2, after 14 days of treatment, the feed chamber also largely returned to clarity. However, due to the relatively small thickness of the barrier adsorption layer, some chromium ions migrated to the receiving chamber, but the overall treatment effect was still very good.

[0107] Combination Figure 3 , Figure 4 and Figure 5 Further analysis reveals that the electrochemical performance and treatment effect of different thicknesses of the isolation adsorption layer show that the current intensity of the 10cm thick barrier chamber is lower than that of the 6cm thick barrier chamber, but the enrichment effect is better. The conductivity of the 3cm thick barrier chamber is higher than that of the 6cm thick barrier chamber, but the enrichment effect is poor and chromium ions are more likely to migrate. Overall, the 6cm thick barrier chamber has a more balanced treatment effect and treatment speed.

[0108] Analysis of Example 1 and Comparative Example 3 Figure 3 It can be seen that when using ordinary electrodes, due to their small specific surface area, harmful ions can easily "contaminate" the electrodes, causing the current intensity to deactivate in a very short time, making continuous electrodialysis adsorption treatment impossible.

[0109] Analysis of Example 1 and Comparative Example 4, combined with Figure 3 It can be seen that when the thickness of the isolation chamber is too small, although the conductivity is improved to some extent, the enrichment effect on harmful ions decreases. Furthermore, harmful ions within the isolation material easily overcome adsorption forces and migrate back into the receiving chamber, causing a rise in the concentration of harmful ions in the receiving chamber, resulting in a poor treatment effect in a short time. Moreover, the high concentration of harmful ions in the receiving chamber significantly impacts the electrodes, easily causing partial deactivation of the electrode material in a short period. Over time, the proportion of deactivated area of ​​the electrode material increases, while the effective area decreases, leading to a sharp drop in current intensity to a very low level. This not only affects the treatment effect but also leads to the scrapping of the electrode material, increasing production costs.

[0110] Analysis of Example 1 and Comparative Example 5, combined with Figure 3 It can be seen that although silica can adsorb and bind a small number of harmful ions on its surface after replacing biomass materials, the adsorption effect is very weak and the amount of harmful ions adsorbed is also very small. The overall enrichment effect is very poor and it cannot treat low-concentration pollutant liquid for a long time.

[0111] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A treatment method for removing harmful ions from a chromium contaminated solution, characterized in that, The application discloses a device for removing harmful ions in chromium-contaminated liquid, which comprises at least one cell pool arranged between an anode and a cathode, a barrier chamber arranged in the cell pool, two supporting net plates, two barrier cloths, a barrier material and a buffer solution, wherein the barrier material and the buffer solution are filled into the gap between the two supporting net plates to form a barrier adsorption layer, the barrier cloths are made of polyester, the barrier material is soil, the buffer solution is a sodium dihydrogen phosphate-sodium hydrogen phosphate system with a pH value of 6.5-7.5, the two supporting net plates are arranged in parallel and oppositely, the distance between the two supporting net plates is 6 cm, the two barrier cloths are respectively attached to the inner surfaces of the two supporting net plates oppositely, the total porosity of the barrier adsorption layer is 30%, and the mass ratio of the barrier material to the buffer solution is 70:

1. The barrier chamber divides the cell pool into a receiving chamber and a liquid chamber, the liquid chamber is provided with diluted chromium-contaminated waste liquid with a chromium ion concentration of 0.05 mol / L, and the receiving chamber is provided with a receiving liquid which is a citric acid-sodium citrate system with a pH value of 6.5-7.

5. The receiving chamber is electrically connected with the cathode, and the liquid chamber is electrically connected with the anode, the anode and the cathode are composed of a conductive net, a binder and a porous electrode material, the porous electrode material is conductive activated carbon with a specific surface area of 300 m2 / g, a direct current electric field is applied to the two sides of the barrier chamber, the voltage is 1.2 V, under the action of the electric field force, the harmful ions migrate from the liquid chamber to the receiving chamber, and are adsorbed and enriched by the barrier material in the migration process.

2. A device for removing harmful ions in chromium-contaminated liquid for the treatment method of claim 1.

Images