CN-121990651-A - Based on Magneli phase Ti4O7Sewage deep treatment method of reactive electrochemical membrane

CN121990651ACN 121990651 ACN121990651 ACN 121990651ACN-121990651-A

Abstract

The invention provides a sewage deep treatment method based on a magneli phase Ti 4 O 7 reactive electrochemical membrane, which comprises the following steps of taking secondary effluent of a municipal sewage treatment plant as a sewage source, injecting the sewage into an open electrochemical reactor after prefiltering, setting the magneli phase Ti 4 O 7 reactive electrochemical membrane as an anode in the center of the electrochemical reactor, setting a stainless steel mesh as a cathode outside the anode, respectively connecting the anode and the cathode to the positive electrode and the negative electrode of a direct current stabilized power supply, pumping out and reinjecting the sewage in the electrochemical reactor at a set flow rate to form a through circulation mode, applying constant current density to perform electrochemical oxidation reaction, and obtaining the recycled effluent. Compared with the prior art, the invention has high current efficiency, strong ARGs removing capability, excellent antibiotic degradation performance and no secondary pollution, and provides a high-efficiency and low-cost solution for advanced sewage treatment.

Inventors

YANG BOXUAN
Wang Dainuo
LI JINWEI
JIANG CHENGCHUN
Chi Huizhong
LI XIAOLIN

Assignees

深圳职业技术大学

Dates

Publication Date: 20260508
Application Date: 20260331

Claims (9)

1. A sewage advanced treatment method based on a magneli phase Ti 4 O 7 reactive electrochemical membrane is characterized by comprising the following steps: Step S1, secondary effluent of a municipal sewage treatment plant is used as a sewage source, and after prefiltering, sewage is injected into an open electrochemical reactor; Step S2, setting a magneli phase Ti 4 O 7 reactive electrochemical membrane as an anode in the center of the electrochemical reactor, setting a stainless steel mesh as a cathode outside the anode, and keeping the electrode spacing constant; Step S3, pumping out and reinjecting the sewage in the electrochemical reactor at a set flow rate to form a through-flow circulation mode, so that the sewage sequentially flows through the pores of the cathode and the anode; And S4, regulating a direct-current stabilized power supply, applying constant current density to perform electrochemical oxidation reaction, monitoring voltage drift in the reaction process in real time, maintaining constant current, and obtaining the water after the cyclic treatment, namely the deep treatment water.
2. The method for the advanced treatment of sewage based on the magneli-phase Ti 4 O 7 -reactive electrochemical membrane according to claim 1, wherein the magneli-phase Ti 4 O 7 -reactive electrochemical membrane is a porous ceramic electrode prepared by a high-temperature hydrogen reduction method, the pore diameter of the porous ceramic electrode is 0.5-2.0 μm, and the polar distance between an anode and a cathode is 1.5-2.5 mm.
3. The method for the advanced treatment of wastewater based on a magneli-phase Ti 4 O 7 reactive electrochemical membrane according to claim 1, characterized in that in step S4, the current density is 0.70mA/cm 2 ～10.90mA/cm 2 .
4. The method for the intensive wastewater treatment of a reactive electrochemical membrane based on the Magneli phase Ti 4 O 7 as claimed in claim 3, wherein in step S4, the current density is 5.80mA/cm 2 ～10.90mA/cm 2 .
5. The method for the advanced treatment of wastewater based on a Magneli-phase Ti 4 O 7 reactive electrochemical membrane according to claim 4, wherein the current density is 10.50-10.90 mA/cm 2 when the secondary effluent contains sulfamethoxazole.
6. The method for the advanced treatment of wastewater based on a magneli-phase Ti 4 O 7 reactive electrochemical membrane according to claim 4, wherein in step S3, the wastewater in the electrochemical reactor is pumped out and reinjected at a set flow rate by a peristaltic pump.
7. The method for the advanced treatment of sewage based on the magneli-phase Ti 4 O 7 reactive electrochemical membrane according to claim 1, wherein the magneli-phase Ti 4 O 7 reactive electrochemical membrane is prepared by the following steps: adding rutile type TiO 2 powder into isopropanol water solution, adding polyethylene oxide binder, pressing into a tube shape, sintering for 18-24 hours at 1000-1100 ℃ in air, and then reducing and sintering for 3-6 hours at 1000-1100 ℃ in hydrogen atmosphere.
8. The method for the advanced treatment of wastewater based on a magneli-phase Ti 4 O 7 -reactive electrochemical membrane according to claim 7, wherein the polyethylene oxide binder is used in an amount of 5wt% based on the mass of the TiO 2 powder and the aqueous isopropanol solution, and the sintering temperature in air and in a hydrogen atmosphere is 1050 ℃.
9. The method for the advanced treatment of wastewater based on a magneli-phase Ti 4 O 7 reactive electrochemical membrane according to claim 7, wherein the volume ratio of isopropanol to water in the aqueous isopropanol solution is 1:1.

Description

Sewage deep treatment method based on magneli phase Ti 4O7 reactive electrochemical membrane Technical Field The invention relates to the technical field of electrochemical water treatment, in particular to a sewage advanced treatment method based on a magneli-phase Ti 4O7 reactive electrochemical membrane. Background With the widespread use of antibiotics, the Antibiotic Resistance Gene (ARGs) has become an emerging environmental pollutant. Conventional biological treatment processes for sewage treatment plants are generally not effective in removing antibiotics and only small amounts of antibiotics can be metabolized, mostly by wastewater discharge into the environment, and even may accelerate ARGs propagation within the sewage treatment plant. China is a large country for antibiotic production and consumption and faces a high ARGs environmental risk. Accordingly, there is an urgent need to develop a technique for effectively removing such contaminants. Electrochemical oxidation is widely studied because of its high efficiency and ease of operation. However, the conventional electrode materials have a plurality of limitations that the doped SnO 2 and PbO 2 electrodes have environmental toxicity risks of heavy metal (such as Sb and Pb) precipitation, and the Boron Doped Diamond (BDD) electrodes have excellent performance but high cost, so that the application of the electrodes in large-scale wastewater treatment is limited. The magneli phase titanium oxide (especially Ti 4O7) has both metal-like conductivity and ceramic-like chemical stability, and has higher oxygen evolution potential, thus being an ideal electrode material. However, the conventional plate electrode is limited by diffusion mass transfer, and the treatment efficiency still has room for improvement. In summary, developing a method for efficiently removing antibiotics and ARGs in secondary effluent by utilizing porous magneli phase Ti 4O7 reactive electrochemical membrane and combining with a flow-through mode to strengthen mass transfer has become an important direction in the field of water advanced treatment. Disclosure of Invention Aiming at the technical problems, the invention discloses a sewage advanced treatment method based on a magneli-phase Ti 4O7 reactive electrochemical membrane, which utilizes the convection mass transfer advantage of a porous electrode to obviously improve the current efficiency, effectively degrade antibiotics and reduce ARGs, and solves the technical problems of high electrode material cost, high heavy metal precipitation risk, low mass transfer efficiency of a traditional plate electrode and the like in the existing electrochemical oxidation technology. In this regard, the invention adopts the following technical scheme: A sewage advanced treatment method based on a magneli phase Ti 4O7 reactive electrochemical membrane comprises the following steps: Step S1, secondary effluent of a municipal sewage treatment plant is used as a sewage source, and after prefiltering, sewage is injected into an open electrochemical reactor; Step S2, setting a magneli phase Ti 4O7 reactive electrochemical membrane as an anode in the center of the electrochemical reactor, setting a stainless steel mesh as a cathode outside the anode, and keeping the electrode spacing constant; Step S3, pumping out and reinjecting the sewage in the electrochemical reactor at a set flow rate to form a through-flow circulation mode, so that the sewage sequentially flows through the pores of the cathode and the anode; And S4, regulating a direct-current stabilized power supply, applying constant current density to perform electrochemical oxidation reaction, monitoring voltage drift in the reaction process in real time, maintaining constant current, and obtaining the water after the cyclic treatment, namely the deep treatment water. In the process of the step, hydroxyl radicals generated on the surface of the anode are utilized to oxidize and degrade antibiotics, resistance genes and organic matters in the sewage, so that the aim of water treatment is fulfilled. The technical proposal utilizes a magneli phase Ti 4O7 reactive electrochemical membrane and a stainless steel mesh as an anode and a cathode respectively, and the porous electrode structure realizes the convective mass transfer of pollutants and overcomes the mass transfer limit of the traditional electrochemical system. The Ti 4O7 reactive electrochemical film has low internal resistance (about 14.2 omega) and good conductivity. The degradation mechanism is clear, and the hydroxyl radical (.OH) plays a dominant role through EPR, namely the main degradation mechanism is the oxidization of the hydroxyl radical (.OH) dominant role, and the oxidization comprises benzene ring hydroxylation, amino oxidization and direct attack of the OH on the molecular structure of the pollutant. Compared with the traditional treatment method, the method provided by the invention has the advantages of excellent