CN-117923618-B - Carbon aerogel adsorption electrode and electric adsorption system based on carbon aerogel adsorption electrode

CN117923618BCN 117923618 BCN117923618 BCN 117923618BCN-117923618-B

Abstract

The invention discloses a carbon aerogel adsorption electrode and an electric adsorption system based on the carbon aerogel adsorption electrode, and the method for preparing the carbon aerogel adsorption electrode adopts a normal pressure drying technology, so that the energy consumption in the electrode preparation process is greatly reduced while the electrode has large porosity; compared with the prior electro-adsorption process for regenerating the circulating cooling water, which needs to suspend adsorption to complete the electrode regeneration process and influence the adsorption and regeneration efficiency, the electro-adsorption system adopts ectopic regenerated electro-adsorption to improve the ion adsorption quantity and simultaneously realize the electrode regeneration in an ectopic way, thereby ensuring the continuous operation of the electro-adsorption process, improving the adsorption and regeneration efficiency and further improving the desalination efficiency.

Inventors

XIONG JIANGLEI
HOU ZHONGKE
SHEN JIGANG
ZHOU WEI
LUO JIAHAO
QI DANNA
YU HONG
FENG JIAN

Assignees

中国电子系统工程第二建设有限公司
江苏中电创新环境科技有限公司

Dates

Publication Date: 20260508
Application Date: 20240111

Claims (10)

1. An electric adsorption system based on carbon aerogel adsorption electrodes is characterized by comprising a reaction box body, an anode region, a water purifying region and a cathode region, wherein the anode region is arranged in the reaction box body and consists of two opposite semicircular cylindrical carbon aerogel adsorption electrodes and a rectangular insulating plate fixed between the two semicircular cylindrical carbon aerogel adsorption electrodes, the semicircular cylindrical carbon aerogel adsorption electrodes of the anode region are coated with anion exchange membranes, the cathode region also consists of two opposite semicircular cylindrical carbon aerogel adsorption electrodes and a rectangular insulating plate fixed between the two semicircular cylindrical carbon aerogel adsorption electrodes, the semicircular cylindrical carbon aerogel adsorption electrodes of the cathode region are coated with the cation exchange membranes, the water purifying region is arranged between the anode region and the cathode region, a water inlet is arranged at the lower part of the water purifying region, a water outlet is arranged at the upper part of the water purifying region, the electric adsorption system further comprises a jacking mechanism and a rotating mechanism, the fixed end of the jacking mechanism is fixed on a bottom plate of the reaction box body through a bearing, the anode region and the cathode region are respectively fixed on a driving end of the jacking mechanism corresponding to the jacking mechanism, the rotating mechanism is fixed on the outer side of the bottom plate of the reaction box body, the rotating mechanism is connected with a driving shaft of the jacking mechanism and the driving mechanism of the jacking mechanism, the four opposite to the four semicircular carbon adsorption electrodes are respectively connected with the four electric adsorption interfaces of the four opposite side of the anode regions, the four electric adsorption mechanisms are arranged on the top plate and the four opposite sides of the reaction box respectively, the semi-cylindrical carbon aerogel adsorption electrode with the anode region and the cathode region relatively close to each other is used as an anode adsorption electrode and a cathode adsorption electrode, the semi-cylindrical carbon aerogel adsorption electrode with the anode region and the cathode region relatively far away from each other is used as an anode regeneration electrode and a cathode regeneration electrode, the anode adsorption electrode and the cathode adsorption electrode are respectively connected with the anode and the cathode of an external power supply through magnetic attraction interfaces, and the anode regeneration electrode and the cathode regeneration electrode are respectively connected with the cathode and the anode of another external power supply through the magnetic attraction interfaces.
2. The electro-adsorption system according to claim 1, wherein the carbon aerogel adsorption electrode is prepared by a method comprising the following steps: (1) Mixing resorcinol and formaldehyde aqueous solution according to the mol ratio of resorcinol to formaldehyde of 1:1-1:3, and adding an alkaline catalyst into the mixture to obtain an RF solution with pH of 10-11; (2) Preparing CTAB dispersion liquid according to the mole ratio of hexadecyl trimethyl ammonium bromide to resorcinol of 0.01-0.1:1, slowly adding the RF solution in the step (1) into the CTAB dispersion liquid, simultaneously adding graphene oxide dispersion liquid with the mass fraction of 0.3-0.4% to obtain mixed liquid, starting magnetic stirring at 80-85 ℃, forming a sol-gel system through crosslinking polymerization reaction, and aging for 3-4 d; (3) Placing the gel formed after aging in a blast drying oven for normal pressure drying, placing the gel into a carbonization furnace after drying, introducing nitrogen for protection, and performing constant temperature heat treatment at 600-1000 ℃ for 2-3 hours to obtain a carbon aerogel electrode material; (4) Mixing 100mL of KMnO 4 solution with the concentration of 0.5-0.7 mol/L with 1g of carbon aerogel electrode material, reacting for 2-3 hours in a hydrothermal reaction kettle with the temperature of 120-150 ℃, and uniformly dispersing the formed nanoscale manganese dioxide on the surface of the graphene-reinforced carbon aerogel adsorption electrode after hydrothermal modification to obtain the MnO 2 -loaded graphene-reinforced carbon aerogel adsorption electrode.
3. The electro-adsorption system according to claim 2, wherein in the step (2), the concentration of graphene oxide in the mixed solution is 2000ppm to 5000ppm.
4. The electro-adsorption system according to claim 2, wherein in the step (3), the drying is performed at a temperature of 70-80 ℃ for 4-5 hours.
5. The electro-adsorption system of claim 1, wherein the water purifying area has a water inlet rectifying plate at the lower part and a water outlet rectifying plate at the upper part, the opening of the water inlet rectifying plate is connected with an external water inlet pipe, and the opening of the water outlet rectifying plate is connected with an external water outlet pipe.
6. The electro-adsorption system according to claim 1, wherein the cylindrical carbon aerogel adsorption electrodes in the anode region and the cathode region are slidingly connected with the rectifying plate.
7. The electro-adsorption system of claim 1, wherein the vertical height of the water inlet rectifying plate and the water outlet rectifying plate is not larger than the height of the anode region or the cathode region, the distance between the water outlet rectifying plate and the top plate of the reaction box body is not smaller than the distance between the jacking front electrode and the magnetic attraction interface, and the distance between the water inlet rectifying plate and the bottom plate of the reaction box body is not smaller than the distance between the jacking mechanism fixed end and the anode region or the cathode region after jacking.
8. The electro-adsorption system according to claim 1, wherein the diameters of the cylindrical anode area and the cylindrical cathode area are the same as the width of the reaction box body, the anode area and the cathode area divide the reaction box body into a water purifying area and a regeneration area, a water inlet is formed in the lower part of the regeneration area, a water outlet is formed in the upper part of the regeneration area, raw water is introduced during electrode regeneration, the regeneration area is the regeneration area, the area where the adsorption electrode is located is the water purifying area, when the rotating mechanism rotates 180 degrees, the semi-cylindrical carbon aerogel adsorption electrode originally used as the adsorption electrode is changed into the regeneration electrode, the electrodes are reversely connected to release the adsorbed ions, and the concentrated water is discharged from the top of the regeneration area.
9. The electro-adsorption system of claim 1, wherein the lifting mechanism is a lifting cylinder, the sum of the heights of the lifting cylinder and the anode region or the cathode region is smaller than the height of the reaction box body before the lifting cylinder is lifted, and the distance between the electrode and the magnetic attraction interface is not larger than 1cm before the lifting cylinder is lifted, so that the lifting height of the lifting cylinder for lifting the anode region and the cathode region is not larger than 1cm.
10. The electro-adhesion system of claim 1, wherein the rotating mechanism is an electric motor.

Description

Carbon aerogel adsorption electrode and electric adsorption system based on carbon aerogel adsorption electrode Technical Field The invention relates to a carbon aerogel adsorption electrode and an electro-adsorption system based on the carbon aerogel adsorption electrode. Background In the operation process of the industrial circulating cooling water system, the water temperature rises after heat exchange between cooling water and a heat exchanger, heat is transferred to air through showering and blowing of a cooling tower, partial water body is evaporated, and CO 2 in the water escapes. After multiple cycles, various inorganic ions and organic ions in the water are continuously concentrated under the influence of evaporation, the pH value is increased due to the escape of CO 2, calcium ions, magnesium ions and the like are easy to reach a supersaturated state, and are crystallized and separated out from the water to form scale, and the scale is deposited on a heat exchange plate to influence the heat transfer efficiency. In order to solve the problems of scale formation, corrosion, microorganism propagation and the like of a circulating cooling water system, improve the concentration multiple of the circulating cooling water and reduce the consumption of supplementing water, medicaments such as corrosion inhibition scale inhibitor, bactericide, slime stripping agent and the like are added, and the medicaments are added to play a role to a certain extent. However, the accurate dosing and other problems exist only depending on the medicament, and the medicament has limited effect when the medicament is too small, so that the operation cost is increased when the medicament is excessive, and other ions can be enriched or foam is generated. Therefore, it is important to construct a circulating cooling water treatment system and reuse the regenerated water as make-up water for the system. Currently, desalination methods such as electrodialysis, reverse osmosis and ion exchange have proven effective, but require high pretreatment requirements and frequent material replacement increases the running cost. The electro-adsorption technology is used as a novel water treatment technology, based on the electric double layer theory, negative ions and positive ions are adsorbed by utilizing the electrochemical characteristics of the electrode surface, the adsorbed ions are released through a reverse or short-circuit power supply, and concentrated water is discharged to realize the purification process. However, when the conventional electro-adsorption system is regenerated, the adsorption process needs to be suspended, and even if a material with high adsorption capacity is selected, the adsorption and regeneration efficiency can be influenced. If two groups of electric adsorption systems are selected, the equipment investment cost is increased. Disclosure of Invention The invention aims to provide a carbon aerogel adsorption electrode which has a micropore-mesopore and macropore structure and a large number of ion embedding channels, so that the adsorption capacity of the electrode to ions is greatly improved, and the desalination rate is improved. The technical scheme is that the carbon aerogel adsorption electrode is prepared by adopting the following method, and specifically comprises the following steps: (1) Mixing resorcinol (Resorcinol, R) with formaldehyde (Formaldehyde; F) in a molar ratio of 1:1-1:3, and adding an alkaline catalyst (NaOH) into the mixture to obtain an RF solution with a pH value of 10-11; (2) Dissolving Cetyl Trimethyl Ammonium Bromide (CTAB) in deionized water to form a dispersion liquid, wherein the molar ratio of the cetyl trimethyl ammonium bromide to resorcinol is 0.01-0.1:1, slowly adding the RF solution obtained in the step (1) into the dispersion liquid, simultaneously adding graphene oxide dispersion liquid with the mass fraction of 0.3% according to the addition amount of 2000-5000 ppm to obtain a mixed liquid, wherein the concentration of graphene oxide in the mixed liquid is 2000-5000 ppm, starting magnetic stirring at 80-85 ℃, forming a sol-gel system through crosslinking polymerization reaction, and then aging for 3-4 d; According to the invention, the carbon aerogel is prepared by adopting an atmospheric pressure drying method, in order to avoid collapse of an aerogel pore structure under the atmospheric pressure drying, cetyl Trimethyl Ammonium Bromide (CTAB) is used as a template agent, gel particles and pore structure formation can be directionally controlled during the cross-linking polymerization reaction of phenolic monomers, and the surface tension effect can be reduced by using the modified carbon aerogel as a surfactant; (3) Placing the gel formed after aging in a blast drying oven for normal pressure drying, and drying for 4-5 hours at the temperature of 70-80 ℃, then placing in a carbonization furnace, introducing nitrogen for protection, and performing constant temper