阅读说明：本技术 一种异质结型类芬顿催化剂、制备方法及专用系统和方法 (Heterojunction type Fenton-like catalyst, preparation method, special system and method ) 是由 吴敏 张冰洁 于 2021-09-03 设计创作，主要内容包括：本发明公开了一种降解高COD含氟废水的异质结型类芬顿催化剂及制备方法与应用及专用系统和方法,该异质结型类芬顿催化剂通式为LaFe-((1-x))Cu-(x)O-(3)/YMoS-(2),其中x为0.1-0.5,Y为0.1-0.5。本发明的催化剂通过Cu掺杂在LaFeO-(3)中得到LaFe-((1-x))Cu-(x)O-(3),再与半导体MoS-(2)复合改性得到。本发明配套处理系统抗氟腐蚀能力强,且耐强酸强碱,杜绝了气体排放的二次污染,不产生铁泥固废二次污染,同时实现废气吸收处理和氟元素的有效收集,绿色环保。采用本发明的催化剂及配套处理专用系统可解决高COD含氟废水难处理、成本高等结构性问题,减少污染,促进可持续发展。(The invention discloses a heterojunction type Fenton-like catalyst for degrading high-COD fluorine-containing wastewater, a preparation method, application, a special system and a special method thereof, wherein the general formula of the heterojunction type Fenton-like catalyst is LaFe (1‑x) Cu x O 3 /YMoS 2 Wherein x is 0.1-0.5 and Y is 0.1-0.5. The catalyst of the invention is doped in LaFeO by Cu 3 To obtain LaFe (1‑x) Cu x O 3 Then with the semiconductor MoS 2 And carrying out composite modification. The matched treatment system has strong fluorine corrosion resistance, resists strong acid and strong alkali, avoids secondary pollution caused by gas emission, does not generate iron mud solid waste secondary pollution, realizes waste gas absorption treatment and effective collection of fluorine elements, and is green and environment-friendly. The catalyst and the special matched treatment system can solve the structural problems of difficult treatment, high cost and the like of the high-COD fluorine-containing wastewater, reduce pollution and promote sustainable development.)

1. The heterojunction type Fenton-like catalyst is characterized in that the catalyst is LaFe₍₁-x)Cu_xO₃/YMoS₂Wherein x is 0.1-0.5, Y is 0.1-0.5, active substance LaFe_(1-x)Cu_xO₃Is in LaFeO₃And modifying the medium doped Cu.

2. A method for producing the heterojunction-type fenton-like catalyst according to claim 1, comprising the steps of:

(1) preparation of Cu-doped catalyst monomer LaFe by sol-gel method_(1-x)Cu_xO₃: dissolving lanthanum nitrate, ferric nitrate and cupric nitrate in water to obtain solution A, dissolving a complexing agent and a surfactant in water to obtain solution B, dripping the solution B into the solution A, carrying out the dripping process under the stirring of a water bath, reacting to obtain gel, drying and grinding to obtain precursor powder, and calcining the precursor powder to obtain the monomer LaFe_(1-x)Cu_xO₃；

(2) Mixing LaFe_(1-x)Cu_xO₃And MoS₂Compounding and preparing catalyst LaFe_(1-x)Cu_xO₃/YMoS₂: dissolving molybdenum salt and sulfur salt in a dispersing agent, stirring and dissolving, adjusting pH, and adding the monomer LaFe obtained in the step (1)_(1-x)Cu_xO₃Stirring, ultrasonic dispersing to obtain mixture, thermal reaction of the mixture in solvent, cooling, washing and drying to obtain LaFe product_(1-x)Cu_xO₃/YMoS₂；

(3) Preparation of shaped catalyst LaFe_(1-x)Cu_xO₃/YMoS₂: the product LaFe is mixed by a dry mixing method_(1-x)Cu_xO₃/YMoS₂Mechanically mixing the carrier, adhesive, lubricant and pore-forming agent, sieving, forming, rolling ball, drying, roasting and sieving to obtain the formed catalyst LaFe_(1-x)Cu_xO₃/YMoS₂。

3. The preparation method according to claim 2, wherein in the step (1), the complexing agent is one of citric acid, maleic acid, oxalic acid, ethanolamine, diethanolamine and glycolic acid, and the surfactant is a G-type or Z-type foaming agent.

4. The method according to claim 2, wherein in the step (1), the molar ratio of lanthanum nitrate to iron nitrate to copper nitrate is 1: 0.5-0.9: 0.1-0.5, wherein the molar ratio of the total molar amount of lanthanum, iron and copper metal ions to the molar amount of the complexing agent is 1: 1-1.5.

5. The method according to claim 2, wherein in the step (2), the molybdenum salt is one of sodium molybdate, ammonium molybdate and ammonium heptamolybdate, the sulfur salt is one of thiourea, N-dimethylformamide, methionine and L-cysteine, and the dispersant is an aqueous solution of ethylene glycol, an aqueous solution of acetonitrile or an aqueous solution of isopropanol.

6. The method according to claim 2, wherein in the step (2), the mass ratio of the molybdenum salt to the sulfur salt is 1: 2; the LaFe_(1-x)Cu_xO₃And MoS₂The mass ratio of (1): 0.1-0.5; the stirring time is 30-60min, and the ultrasonic dispersion timeThe pH value is 10-30min, and the pH value adjusting range is 7-11; the solvent thermal reaction temperature is 180-220 ℃, and the reaction time is 16-24 h.

7. Use of the heterojunction-type fenton-like catalyst of claim 1 for treating high COD fluorine-containing wastewater.

8. The special system for treating high COD fluorine-containing wastewater by using the heterojunction type Fenton-like catalyst in claim 1 is characterized by comprising a mixer (2) with a pH electrode, a heat exchanger (4), a reaction tank (6), a demister (9), an absorption tower (14), a reagent pump (15) and a sedimentation tank (17); the reaction tank (6) is internally divided into catalytic reaction areas (a, b) and a water outlet area (c), catalyst filling areas (7) and theta rings (8) which are alternately stacked are arranged in the catalytic reaction areas (a, b) of the reaction tank (6), a demister (9) is arranged at the upper parts of the catalytic reaction areas (a, b) of the reaction tank (6), a liquid level sensor (10) is arranged on the side wall of the reaction tank (6), and the inner wall and all components of the reaction tank (6) are covered with a polytetrafluoroethylene lining; wherein, the catalytic reaction areas (a, b) and the water outlet area (c) of the reaction tank (6) are respectively connected with a sedimentation tank (17) through a mixer (2) with a pH electrode and a heat exchanger (4), the top of the reaction tank (6) is connected with an absorption tower (14), and a fluorine ion detection probe (18) is arranged in the sedimentation tank (17).

9. The method for treating the fluorine-containing wastewater with high COD by using the special system of claim 8 is characterized by comprising the following steps: conveying high-COD fluorine-containing wastewater to a mixer (2) with a pH electrode for pH measurement, entering a heat exchanger (4) for heat exchange, mixing the heated wastewater with an oxidant input by a reagent pump (15), then entering a reaction tank (6) from an inlet of a zone a and an inlet of a zone b of the reaction tank (6), flowing through a catalyst filling zone (7) provided with the heterojunction type Fenton-like catalyst according to claim 1 and a theta ring (8) from bottom to top, defoaming the treated wastewater through a demister (9), detecting the liquid level by a liquid level sensor (10), overflowing the treated wastewater from top to bottom to flow out from an outlet of a zone c of the reaction tank (6), detecting COD of the wastewater, if the COD value meets the requirement, conveying the wastewater to a sedimentation tank (17) for fluoride ion sedimentation, and if the COD value does not meet the requirement, returning the wastewater to the reaction tank (6) for continuous treatment after passing through the mixer (2) with the pH electrode and the heat exchanger (4). The gas generated in the treatment process is sent to an absorption tower (14) for absorption treatment. The sedimentation tank (17) sediments the fluorine ions, and if the fluorine ions detected by the fluorine ion detection probe (18) are qualified, the wastewater is discharged out of the system.

10. The method as claimed in claim 9, wherein the COD value of the high COD fluorine-containing wastewater is 7575-15150mg/L, and the fluorine ion concentration in the high COD fluorine-containing wastewater is 140-278 mg/L.

Technical Field

The invention relates to a composite catalyst, a preparation method, a special system and a special method, in particular to a heterojunction type Fenton-like catalyst which has high catalytic activity and good fluorine resistance and can effectively degrade high-COD fluorine-containing wastewater, a preparation method thereof, and a special system and a special method for matched treatment.

Background

The application of fluorine-containing products relates to the industrial production of metal smelting, organic fluorine, phosphate fertilizer, pesticide, glass, electrolytic aluminum, pharmacy, semiconductor and the like. Among them, the fluorine-containing organic polymer material is widely used in fluorine refrigerants, fluorine paints, fluororubbers, fluororesin products, etc. because it has specific aging resistance, thermal stability, electrical insulation, chemical resistance, flame retardancy, and surface non-adhesiveness. According to statistics, the fluorine-containing polymer occupies about 20% of the total fluorine consumption in the whole fluorine chemical industry, the application field is still continuously expanded, and the fluorine-containing high polymer material can meet wider demand prospects. However, fluorine element has strong electronegativity, so that fluoride with low melting point is generated in the process of catalytic degradation, and further, the sintering of the surface of the catalyst is accelerated, and the catalyst is poisoned. In the process of producing fluorine-containing organic polymer chemical products, upstream raw materials of fluorite and concentrated sulfuric acid react in a converter to generate furnace gas, the furnace gas can generate a large amount of high-COD fluorine-containing wastewater in subsequent separation, washing and distillation processes, fluorine-containing compounds combined with organic matters have strong chemical stability and are difficult to break bonds, and the wastewater has the characteristics of high concentration, poor biodegradability, difficult degradation, large change of water quality and water quantity and the like. In addition, scientific research finds that fluorine has strong affinity to calcium and phosphorus in human body, can destroy normal metabolism of calcium and phosphorus in the body, and can inhibit the activity of certain enzymes, thereby triggering a series of actions including: the diseases such as dental fluorosis, kidney, liver and brain damage, immunologic dysfunction, pulmonary edema, pulmonary hemorrhage, children intelligence decline and the like are extremely harmful to human bodies, and the primary standard of the Integrated wastewater discharge Standard (GB8978-1996) in China is definitely stipulated, and the fluorine content of industrial wastewater is lower than 10 mg/L.

At present, the mainstream methods for treating the high-COD fluorine-containing industrial wastewater are a precipitation method and an adsorption method, and the emerging treatment methods comprise a fluidized bed crystallization method, a reverse osmosis method, an electrocoagulation method and an ion exchange method, are still in a laboratory research stage and have less industrial application. The chemical precipitation method is widely applied in industry, but the sludge generated in the precipitation process has high water content, low recovery value and difficult treatment and disposal, while the adsorption method has low treatment concentration, relatively high price and is easy to cause secondary pollution. The advanced oxidation technology is mature for treating high COD wastewater, but because of strong electronegativity of fluorine element, catalyst poisoning is easily caused, and the effect of treating fluorine-containing wastewater is not ideal. Therefore, the preparation of a catalyst which has strong fluorine resistance and can treat organic wastewater with high COD and a matched treatment system are very important.

Disclosure of Invention

The purpose of the invention is as follows: a first object of the present invention is to provide a heterojunction-type fenton-like catalyst; the second purpose of the invention is to provide a preparation method of the heterojunction type Fenton-like catalyst; the third purpose of the invention is to provide an application of the heterojunction type Fenton-like catalyst in treating high-COD fluorine-containing wastewater; the fourth purpose of the invention is to provide a special strong fluorine-resistant matched treatment system for treating the high-COD fluorine-containing wastewater by using the heterojunction type Fenton-like catalyst; the fifth purpose of the invention is to provide a method for treating high-COD fluorine-containing wastewater by utilizing the heterojunction type Fenton-like catalyst and a special strong fluorine-resistant matched treatment system.

The technical scheme is as follows: the heterojunction type Fenton-like catalyst is LaFe_(1-x)Cu_xO₃/YMoS₂Wherein x is 0.1-0.5, Y is 0.1-0.5, active substance LaFe_(1-x)Cu_xO₃Is in LaFeO₃And modifying the medium doped Cu. The x represents the mol percentage content of Cu doping, and the Y represents the composite semiconductor MoS₂Is LaFe_(1-x)Cu_xO₃The mass ratio of (a).

The preparation method of the heterojunction type Fenton-like catalyst comprises the following steps:

(1) preparation of Cu-doped catalyst monomer LaFe by sol-gel method_(1-x)Cu_xO₃: dissolving lanthanum nitrate, ferric nitrate and cupric nitrate in water to obtain solution A, and mixing complexing agent and surface active agentDissolving the solvent in water to obtain solution B, dripping solution B into solution A, reacting under stirring in water bath to obtain gel, drying, grinding to obtain precursor powder, and calcining the precursor powder to obtain LaFe monomer_(1-x)Cu_xO₃；

(2) Mixing LaFe_(1-x)Cu_xO₃And MoS₂Compounding and preparing heterojunction type Fenton-like catalyst LaFe_(1-x)Cu_xO₃/YMoS₂: dissolving molybdenum salt and sulfur salt in a dispersing agent, stirring and dissolving, adjusting pH, and adding the monomer LaFe obtained in the step (1)_(1-x)Cu_xO₃Stirring, ultrasonic dispersing to obtain mixture, thermal reaction of the mixture, cooling, washing and drying to obtain LaFe product_(1-x)Cu_xO₃/YMoS₂；

(3) Preparation of shaped catalyst LaFe_(1-x)Cu_xO₃/YMoS₂: the product LaFe is mixed by a dry mixing method_(1-x)Cu_xO₃/YMoS₂Mechanically mixing the carrier, adhesive, lubricant and pore-forming agent, sieving, forming, rolling ball, drying, roasting and sieving to obtain the formed catalyst LaFe_(1-x)Cu_xO₃/YMoS₂。

Further, in the step (1), the complexing agent is one of citric acid, maleic acid, oxalic acid, ethanolamine, diethanolamine and glycolic acid.

Further, in the step (1), the surfactant is a G-type or Z-type foaming agent.

Further, in the step (1), the molar ratio of the lanthanum nitrate to the ferric nitrate to the cupric nitrate is 1: 0.5-0.9: 0.1-0.5, wherein the molar ratio of the total molar amount of lanthanum, iron and copper metal ions to the molar amount of the complexing agent is 1: 1-1.5.

Further, in the step (1), the temperature of the water bath is 70-85 ℃, and the drying temperature is 80-120 ℃.

Further, in the step (1), the calcining temperature is programmed heating, the temperature is raised to 600 ℃ at the speed of 5 ℃/min, the temperature is kept for 2h, the temperature is raised to 800 ℃ at the speed of 5 ℃/min, the temperature is kept for 2h, and the temperature is naturally cooled to the room temperature.

Further, in the step (2), the molybdenum salt is one of sodium molybdate, ammonium molybdate and ammonium heptamolybdate.

Further, in the step (2), the sulfur salt is one of thiourea, N-dimethylformamide, methionine and L-cysteine.

Further, in the step (2), the dispersing agent is ethylene glycol aqueous solution, acetonitrile aqueous solution or isopropanol aqueous solution.

Further, in the step (2), the mass ratio of the molybdenum salt to the sulfur salt is 1: 2; the LaFe_(1-x)Cu_xO₃And MoS₂The mass ratio of (1): 0.1-0.5.

Further, in the step (2), the stirring time is 30-60min, and the ultrasonic dispersion time is 10-30 min.

Further, in the step (2), 1mol/L sodium hydroxide solution is selected for pH adjustment, and the pH adjustment range is 7-11.

Further, in the step (2), the solvothermal reaction temperature is 180-220 ℃, and the reaction time is 16-24 h.

Further, in the step (3), the mixing process is carried out in a closed container with stirring, a small amount of water is added after the mixing is fully carried out, and the mixture is sieved, molded, dried and roasted.

The heterojunction type Fenton-like catalyst disclosed by the invention is applied to treatment of high-COD fluorine-containing wastewater.

The special system for treating the high-COD fluorine-containing wastewater by using the heterojunction type Fenton-like catalyst is a complete treatment system of the heterojunction type Fenton-like catalyst adaptation process-fluorine-resistant high-COD wastewater, and comprises a mixer with a pH electrode, a heat exchanger, a reaction tank, a demister, an absorption tower, a reagent pump and a sedimentation tank; the reaction tank is internally divided into a catalytic reaction zone and a water outlet zone, a catalyst filling zone and a theta ring which are alternately stacked are arranged in the catalytic reaction zone, a demister is arranged at the upper part of the catalytic reaction zone of the reaction tank, a liquid level sensor is arranged on the side wall of the reaction tank, and the inner wall of the reaction tank and all components thereof are covered with a layer of polytetrafluoroethylene lining; wherein, the catalytic zone and the water outlet zone of the reaction tank are respectively connected with a sedimentation tank through a mixer with a pH electrode and a heat exchanger, the top of the reaction tank is connected with an absorption tower, and a fluorine ion detection probe is arranged in the sedimentation tank.

The method for treating the high-COD fluorine-containing wastewater by using the fluorine-resistant high-COD wastewater complete treatment system comprises the following steps of: conveying the high-COD fluorine-containing wastewater to a mixer with a pH electrode for measuring and regulating pH, entering a heat exchanger for heat exchange, mixing the heated wastewater with an oxidant input by a reagent pump, then entering a reaction tank from an inlet of a catalytic reaction zone of the reaction tank, flowing through a catalyst filling zone filled with the heterojunction type Fenton-like catalyst and a theta ring from bottom to top, defoaming the treated wastewater by a demister, detecting the treated wastewater by a liquid level sensor to reach a liquid level, overflowing the treated wastewater from top to bottom to flow out from an outlet of a water outlet zone of the reaction tank, detecting COD of the wastewater, conveying the wastewater to a sedimentation tank for sedimentation of fluoride ions if the COD value meets the requirement, and returning the wastewater to the reaction tank for continuous treatment after passing through the mixer with the pH electrode and the heat exchanger if the COD value does not meet the requirement. And the gas generated in the treatment process is sent to an absorption tower for absorption treatment. And (4) precipitating fluorine ions in the sedimentation tank, and if the fluorine ions detected by the fluorine ion detection probe are qualified, discharging the wastewater out of the system.

Furthermore, the COD value of the fluorine-containing wastewater with high COD is 7575-15150mg/L, and the fluorine ion concentration in the fluorine-containing wastewater with high COD is 140-278 mg/L.

Further, the mass ratio of the catalyst filled in the catalyst filling area to the high-COD fluorine-containing wastewater is 0.2: 1.

further, 1mol/L sodium hydroxide solution and 1mol/L dilute sulfuric acid solution are selected for pH adjustment, and the pH is 4-8.

Further, the oxidant is hydrogen peroxide, and the volume ratio of the hydrogen peroxide to the high COD fluorine-containing wastewater is 0.1: 1.

further, the absorption liquid in the gas absorption tower is a mixed solution of sodium bicarbonate and sodium carbonate.

Further, the reaction pressure in the reaction tank is normal pressure, and the reaction temperature is 70-75 ℃.

Further, the sedimentation tank adopts the reaction of calcium ions and fluoride ions to collect fluorine elements.

In the preparation of LaFe_(1-x)Cu_xO₃In the monomer process, the type and the molar weight of the complexing agent are controlled to be used for dispersing colloid particles to form the most stable metal ion complex, so that the agglomeration of powder in the calcining process is reduced; by controlling the calcining procedure, LaFe which is uniformly dispersed, has uniform particle size and good perovskite crystal form is obtained_(1-x)Cu_xO₃A monomer. In the preparation of LaFe_(1-x)Cu_xO₃/YMoS₂In the process, the heterojunction type Fenton-like catalyst without changing the perovskite crystal structure is obtained by compounding the thermal reactions of different dispersants at different temperatures. Due to doping of LaFe_(1-x)Cu_xO₃The stable perovskite structure is difficult to maintain, the control of the polarity of a solvent in thermal reaction is particularly important, and different from the preparation method in the prior art, water is not used as a main reaction medium of solvothermal reaction in the method provided by the invention but used for dissolving and dispersing molybdenum salt and sulfur salt.

The metal ions dissolved out by the catalyst in the process of degrading the high-COD fluorine-containing wastewater are lower than the ppm level, and the high-activity and high-oxidability OH degradation high-COD wastewater is generated by efficiently utilizing the oxidant without generating iron mud solid waste secondary pollution. The matched treatment system is specially designed for wastewater containing fluorine, namely polytetrafluoroethylene coating is modified on the inner liner of the reaction system, so that corrosion of fluorine ions dissolved out in the degradation process to equipment is reduced, the service life of the equipment is prolonged, and the matched treatment system is distinguished from the traditional Fenton method.

Doping of the catalyst Cu of the invention causes LaFeO₃Lattice defects exist in LaFeO in the form of interstitial ions₃In the crystal lattice, the composite particles have impurity energy levels, which is beneficial to the transfer of current carriers and improves the utilization rate of hydrogen peroxide; MoS₂The compounding of the semiconductor can increase the specific surface area of the catalyst and enhance the adsorption performance, and can form an acidic environment on the surface of the catalyst to construct iron ions with different valence states for microcirculation, thereby realizing the effective decomposition of hydrogen peroxide and finally achieving the high-efficiency degradation of the high-COD fluorine-containing wastewater. According to the inventionCatalyst modified by Cu doping and semiconductor MoS₂The compound modification further forms an impurity level and an acid environment on the surface of the catalyst, is beneficial to the transfer of current carriers, and promotes the effective decomposition of hydrogen peroxide; the special matched treatment system is based on the catalyst, OH generated by effective decomposition of hydrogen peroxide is fully utilized to catalyze and oxidize the high-COD fluorine-containing wastewater, and the special matched treatment system simultaneously realizes waste gas absorption treatment and effective collection of fluorine elements. The catalyst and the special matched treatment system can be used for solving the structural problems of difficult treatment, high cost and the like of the high-COD fluorine-containing wastewater, reducing pollution and promoting sustainable development.

Has the advantages that: compared with the prior art, the invention has the following remarkable advantages:

(1) the invention dopes Cu with modified LaFe_(1-x)Cu_xO₃And MoS₂The heterojunction type Fenton-like catalyst is formed by combination, the high-COD fluorine-containing wastewater can be effectively degraded, the degradation rate of COD is more than 65%, and the content of fluorine ions in the degraded water is less than 10 mg/L.

(2) The preparation method of the heterojunction type Fenton-like catalyst is simple to operate, the raw materials are easy to obtain, and the cost is low; the method has the advantages of simple required equipment and flexible process, and realizes the monomer LaFe by controlling the temperature rise in the calcining process in the preparation process_(1-x)Cu_xO₃The problem of poor catalytic activity caused by easy agglomeration of crystal grains is solved by nano-scale regulation, the specific surface area is increased, and the activity and the stability are improved; simultaneously, different dispersants at different temperatures are selected for compounding through thermal reaction to obtain LaFe_(1-x)Cu_xO₃/YMoS₂Realize MoS₂In-situ growth on monomer LaFe_(1-x)Cu_xO₃The two are uniformly distributed, and the catalytic activity is improved.

(3) The invention relates to a special system for matching treatment of a composite photocatalyst, so that the catalyst LaFe_(1-x)Cu_xO₃/YMoS₂Under normal pressure, a large amount of OH can be generated through decomposition so as to enhance the utilization efficiency of hydrogen peroxide and realize the effective degradation of the fluorine-containing wastewater with high COD; the system supports multiple cycles to treat the high COD fluorine-containing wastewater and can effectively collect the wastewaterCollecting fluorine elements; the reaction tank adopts polytetrafluoroethylene as a lining, has strong fluorine corrosion resistance and strong acid and alkali resistance; the tail gas absorption device avoids secondary pollution of gas emission; compared with the traditional Fenton method, the method does not produce secondary pollution of iron mud solid waste, and is green and environment-friendly.

Drawings

FIG. 1 is a process flow diagram of the catalyst of the present invention for degrading high COD fluorine-containing wastewater in a dedicated system;

FIG. 2 is a top view of the interior of the reaction tank;

FIG. 3 shows LaFe as a powdery heterojunction-type Fenton-like catalyst prepared in example 3_0.5Cu_0.5O₃/0.3MoS₂；

FIG. 4 shows shaped heterojunction-type Fenton-like catalyst LaFe prepared in example 3_0.5Cu_0.5O₃/0.3MoS₂。

Detailed Description

Example 1

As shown in figure 1, the special system for degrading the high-COD fluorine-containing wastewater by the catalyst comprises a reaction module, a heat exchange module, a precipitation module and a tail gas absorption module. The reaction module comprises a reaction tank 6, wherein the top of the reaction tank 6 is provided with a safety valve 11, a pressure gauge 12 and an exhaust valve 13, the inside of the reaction tank 6 is divided into a region a and a region b of a catalytic reaction region and a region c of a water outlet region, the region c is divided into two parts, and the tops of the region a and the region b of the catalytic reaction region are communicated with the two parts of the region c. Catalyst filling areas 7 and theta rings 8 which are alternately stacked are arranged inside the two catalytic reaction areas of the reaction tank 6, the reaction tank 6 is internally divided into the two catalytic reaction areas, the upper part of the reaction tank is provided with a demister 9, the side wall of the reaction tank 6 is provided with a liquid level sensor 10 (L1-L2) and a temperature sensor 19, the inner wall of the reaction tank 6 and components thereof are both covered with a layer of polytetrafluoroethylene lining, and the outside of the reaction tank 6 is made of carbon steel. The heat exchange module in figure 1 comprises a pneumatic three-way ball valve 1, a mixer 2 with a pH electrode, a liquid inlet pump 3, a heat exchanger 4, a pneumatic three-way ball valve 5, a reagent pump 15 and a one-way valve 16. The sedimentation module comprises a sedimentation tank 17, and a fluorine ion detection probe 18 is arranged in the sedimentation tank 17. The tail gas absorption module comprises a tail gas absorption tower 14, and a spray header is arranged at the top of the tail gas absorption tower 14. The pneumatic three-way ball valve 1 is respectively connected with a mixer 2 with a pH electrode and an outlet area c outlet of a reaction tank 6, the mixer 2 with the pH electrode is connected with a heat exchanger 4 through a liquid inlet pump 3, the pneumatic three-way ball valve 5 is respectively connected with the heat exchanger 4, a sedimentation tank 17 and a reagent pump 15, the reagent pump 15 is respectively connected with a pneumatic three-way ball valve 5 and an area a inlet and an area b inlet of the reaction tank 6, a one-way valve 16 is respectively connected with the area a inlet and the area b inlet of the reaction tank 6 and the mixer 2 with the pH electrode, and the reaction tank 6 is connected with a tail gas absorption tower 14 through an exhaust valve 13. The heating medium of the heat exchanger 4 is water vapor, and the steam enters from top to bottom.

(1)LaFe_0.9Cu_0.1O₃Preparation of

According to a molar ratio of 1: 0.9: 0.1 weight 2.1650g lanthanum nitrate hexahydrate, 1.8180g ferric nitrate nonahydrate and 0.1208g cupric nitrate trihydrate, and dissolve them in 10mL distilled water to obtain solution A. According to the molar ratio of the total molar amount of lanthanum, iron and copper metal ions to diethanolamine being 1: 1.2 weighing 1.2617g diethanolamine and 0.05g G type foaming agent dissolved in 40mL distilled water to obtain solution B, dripping solution B into solution A by peristaltic pump at the flow rate of 0.5mL/min, and stirring in 70 deg.C water bath. Reacting to generate sol gel, drying the gel in a forced air drying oven at 85 ℃ overnight, grinding to obtain precursor powder, heating the precursor powder to 600 ℃ at a speed of 5 ℃/min, keeping the temperature for 2h, continuing heating to 800 ℃ at a speed of 5 ℃/min, keeping the temperature for 2h, and naturally cooling to obtain the LaFe monomer_0.9Cu_0.1O₃。

(2)LaFe_0.9Cu_0.1O₃/0.3MoS₂Preparation of

Mixing sodium molybdate dihydrate and thiourea according to a mass ratio of 1: 2.0.4534 g of sodium molybdate dihydrate and 0.9069g of thiourea were respectively weighed out and dissolved in 60mL of an aqueous ethylene glycol solution (50mL of ethylene glycol +10mL of water) with stirring, the pH was adjusted to 7 with 1mol/L of a sodium hydroxide solution, and then 1g of LaFe monomer was added thereto_0.9Cu_0.1O₃Stirring for 30min, ultrasonically dispersing for 30min to obtain a mixture, transferring the mixture into a 100mL polytetrafluoroethylene reaction kettle, carrying out solvothermal reaction at 200 ℃ for 16h, naturally cooling, washing with water and ethanol for three times respectively, and drying at 80 ℃ overnight to obtain a final product LaFe_0.9Cu_0.1O₃/0.3MoS₂。

(3) Shaped catalyst LaFe_0.9Cu_0.1O₃/0.3MoS₂Preparation of

The catalyst 20g LaFe is mixed by dry mixing method_0.9Cu_0.1O₃/0.3MoS₂100g of activated carbon, 10g of methylcellulose, 1g of stearic acid and 1mL of polyethylene glycol are put into a mixer together, 17mL of water is added into the mixer, the mixture is mixed and pulped, the treatment time is 2 hours, the slurry is dried, crushed and sieved, the particle size of the obtained powder is less than or equal to 50 micrometers, the obtained mixed material is rolled and molded, a rotary drum is selected for drying, then the obtained product is roasted for 4 hours at 800 ℃ in the nitrogen atmosphere, and the spherical catalyst LaFe with the particle size of 3-4mm is obtained after sieving treatment_0.9Cu_0.1O₃/0.3MoS₂。

(4) Catalyst LaFe_0.9Cu_0.1O₃/0.3MoS₂Degrading high COD fluorine-containing wastewater

As shown in figure 1, 10L of high COD fluorine-containing wastewater (COD is 7575mg/L, the concentration of fluorinion is 140mg/L) enters a mixer 2 with a pH electrode through a pneumatic three-way ball valve 1(a, b is opened), after the pH is measured to be 4-8, the wastewater enters a heat exchanger 4 through a liquid inlet pump 3 for heat exchange, after the heat exchange, 30% hydrogen peroxide (the flow rate is 100mL/min, the total amount is 1L) sent by a pneumatic three-way ball valve 5(a, b is opened) and a reagent pump 15 is premixed, the premixed water enters a reaction tank 6 through an inlet of an area a and an inlet of an area b of the reaction tank 6, and the reaction tank 6 sequentially and repeatedly flows through a spherical catalyst LaFe from bottom to top_0.9Cu_0.1O₃/0.3MoS₂The catalyst filling area 7 and the theta ring 8 are monitored by a temperature sensor 19 to have a reaction temperature of 70-75 ℃, treated sewage is subjected to defoaming by a demister 9 and then is detected by a liquid level sensor 10(L2), when the liquid level reaches 90cm of a reaction tank, a pneumatic three-way ball valve 1(a, c is opened), the treated wastewater overflows from top to bottom into two parts of a c area of the reaction tank 6 and flows out from an outlet of the c area of the reaction tank 6 and is subjected to circulating treatment by the pneumatic three-way ball valve 1(a, c is opened), gas generated in the treatment process is monitored by a pressure gauge 12 to exceed 0.5MPa, the gas is conveyed to the bottom of an absorption tower 14 by an exhaust valve 13 to be subjected to absorption treatment from bottom to top, and the absorption in the absorption tower 14 is subjected to absorption treatment from bottom to topThe liquid is a mixed solution of sodium bicarbonate and sodium carbonate, and the spray head at the upper part of the absorption tower 14 sprays and absorbs the gas. After the wastewater is repeatedly treated and COD detection is qualified, the one-way valve 16 and the a and c of the pneumatic three-way ball valve 5 are opened, the qualified water is discharged through the inlet of the a area, the inlet of the b area and the outlet of the c area at the bottom of the reaction tank 6 at the same time, and the qualified water is conveyed to a sedimentation tank 17 containing calcium ions through a mixer 2 with a pH electrode, a liquid inlet pump 3, a heat exchanger 4 and the pneumatic three-way ball valve 5 to carry out sedimentation treatment on the fluorine ions. And discharging the qualified product after being detected by the fluorine ion detection probe 18. When the liquid level sensor 10(L1) detects that the liquid level is 0cm as the treated water in the reaction tank 6 is discharged, the pneumatic three-way ball valve 1(a, b is opened) is used for the next batch treatment. The safety valve 11 at the top of the reaction tank 6 is carefully controlled in the whole operation process, so that the operation safety is ensured. And finally detecting the COD value. The specific treatment results are shown in Table 1.

TABLE 1

Example 2:

(1)LaFe_0.7Cu_0.3O₃preparation of

According to a molar ratio of 1: 0.7: 0.3 lanthanum nitrate hexahydrate 2.1650g, ferric nitrate nonahydrate 1.4140g and cupric nitrate trihydrate 0.3624g were weighed and dissolved in 10mL of distilled water to obtain solution A. According to the molar ratio of the total molar amount of lanthanum, iron and copper metal ions to maleic acid being 1: 1.3 1.5089g of maleic acid and 0.05gZ of foaming agent are weighed and dissolved in 40mL of distilled water to obtain solution B, the solution B is dripped into the solution A through a peristaltic pump at the flow rate of 0.5mL/min, and the whole dripping process is carried out under the stirring of a water bath at the temperature of 80 ℃. Reacting to generate sol gel, drying the gel in a forced air drying oven at 80 ℃ overnight, grinding to obtain precursor powder, heating the precursor powder to 600 ℃ at a speed of 5 ℃/min, keeping the temperature for 2h, continuing heating to 800 ℃ at a speed of 5 ℃/min, keeping the temperature for 2h, and naturally cooling to obtain the LaFe monomer_0.7Cu_0.3O₃。

(2)LaFe_0.7Cu_0.3O₃/0.3MoS₂Preparation of

Mixing sodium molybdate dihydrate with N, N-dimethylformamide according to a mass ratio of 1: 2 0.4534g of sodium molybdate dihydrate and 0.9069g of N, N-dimethylformamide are respectively weighed and dissolved in 60mL of ethylene glycol aqueous solution (50mL of ethylene glycol and 10mL of water) with stirring, the pH is adjusted to 11 with 1mol/L of sodium hydroxide solution, and then 1g of LaFe monomer is added_0.7Cu_0.3O₃Stirring for 45min, ultrasonically dispersing for 10min to obtain a mixture, transferring the mixture into a 100mL polytetrafluoroethylene reaction kettle, carrying out solvothermal reaction for 20h at 200 ℃, naturally cooling, washing with water and ethanol for three times respectively, and drying at 80 ℃ overnight to obtain a final product LaFe_0.7Cu_0.3O₃/0.3MoS₂。

(3) Shaped catalyst LaFe_0.7Cu_0.3O₃/0.3MoS₂Preparation of

The procedure was as in example 1.

(4) Catalyst LaFe_0.7Cu_0.3O₃/0.3MoS₂Degrading high COD fluorine-containing wastewater

The treatment process was the same as in example 1, wherein the initial COD of the high COD fluorine-containing wastewater was 7575mg/L, the fluoride ion concentration was 140mg/L, and the specific treatment results are shown in Table 2.

TABLE 2

Example 3

(1)LaFe_0.5Cu_0.5O₃Preparation of

According to a molar ratio of 1: 0.5: 0.5 lanthanum nitrate hexahydrate 2.1650g, ferric nitrate nonahydrate 1.0100g and cupric nitrate trihydrate 0.6040g were weighed and dissolved in 10mL of distilled water to obtain solution A. According to the molar ratio of the total molar amount of lanthanum, iron and copper metal ions to citric acid being 1: 1.2 2.5217g of citric acid and 0.05g of G-type foaming agent were weighed and dissolved in 40mL of distilled water to obtain solution B, and solution B was added dropwise to solution A by means of a peristaltic pump at a flow rate of 0.5mL/min, and the whole dropwise addition was carried out in a water bath at 80 ℃ with stirring. Reacting until sol gel is formed, and coagulatingDrying the glue in a blast drying oven at 85 ℃ overnight, grinding to obtain precursor powder, heating the precursor powder to 600 ℃ at a speed of 5 ℃/min, preserving heat for 2h, continuing heating to 800 ℃ at a speed of 5 ℃/min, preserving heat for 2h, and naturally cooling to obtain the monomer LaFe_0.5Cu_0.5O₃。

(2)LaFe_0.5Cu_0.5O₃/0.3MoS₂Preparation of

Mixing sodium molybdate dihydrate and thiourea according to a mass ratio of 1: 2.0.4534 g of sodium molybdate dihydrate and 0.9069g of thiourea were respectively weighed out and dissolved in 60mL of an aqueous ethylene glycol solution (50mL of ethylene glycol +10mL of water) with stirring, the pH was adjusted to 7 with 1mol/L of a sodium hydroxide solution, and then 1g of LaFe monomer was added thereto_0.5Cu_0.5O₃Stirring for 60min, ultrasonically dispersing for 10min to obtain a mixture, transferring the mixture into a 100mL polytetrafluoroethylene reaction kettle, carrying out solvothermal reaction for 24h at 200 ℃, naturally cooling, washing with water and ethanol for three times respectively, and drying at 80 ℃ overnight to obtain a final product LaFe_0.5Cu_0.5O₃/0.3MoS₂As shown in fig. 3.

(3) Shaped catalyst LaFe_0.5Cu_0.5O₃/0.3MoS₂Preparation of

The procedure is as in example 1, giving the shaped catalyst LaFe_0.5Cu_0.5O₃/0.3MoS₂As shown in fig. 4.

(4) Catalyst LaFe_0.5Cu_0.5O₃/0.3MoS₂Degrading high COD fluorine-containing wastewater

The treatment process is the same as that of example 1, wherein the initial COD of the high-COD fluorine-containing wastewater is 7575mg/L, the fluorine ion concentration is 140mg/L, and the specific treatment results are shown in Table 3.

TABLE 3

Example 4

(1)LaFe_0.5Cu_0.5O₃Preparation of

According to a molar ratio of 1: 0.5:0.5 lanthanum nitrate hexahydrate 2.1650g, ferric nitrate nonahydrate 1.0100g and cupric nitrate trihydrate 0.6040g were weighed and dissolved in 10mL of distilled water to obtain solution A. According to the molar ratio of the total molar amount of lanthanum, iron and copper metal ions to the molar amount of glycolic acid being 1: 1.1 0.8366g of glycolic acid and 0.05gZ type foaming agent are weighed and dissolved in 40mL of distilled water to obtain solution B, the solution B is dripped into the solution A through a peristaltic pump at the flow rate of 0.5mL/min, and the whole dripping process is carried out under the stirring of a water bath at the temperature of 85 ℃. Reacting to generate sol gel, drying the gel in a blast drying oven at 120 ℃ overnight, grinding to obtain precursor powder, heating the precursor powder to 600 ℃ at the speed of 5 ℃/min, keeping the temperature for 2h, then continuously heating to 800 ℃ at the speed of 5 ℃/min, keeping the temperature for 2h, and naturally cooling to obtain the LaFe monomer_0.5Cu_0.5O₃。

(2)LaFe_0.5Cu_0.5O₃/0.1MoS₂Preparation of

Mixing sodium molybdate dihydrate with L-cysteine according to the mass ratio of 1: 2 0.1225g of sodium molybdate dihydrate and 0.2449g of L-cysteine are respectively weighed and dissolved in 60mL of ethylene glycol aqueous solution (50mL of ethylene glycol and 10mL of water) by stirring, the pH is adjusted to 8 by 1mol/L of sodium hydroxide solution, and then 1g of LaFe monomer is added_0.5Cu_0.5O₃Stirring for 30min, ultrasonically dispersing for 30min to obtain a mixture, transferring the mixture into a 100mL polytetrafluoroethylene reaction kettle, carrying out solvothermal reaction for 24h at 200 ℃, then naturally cooling, washing with water and ethanol for three times respectively, and drying at 80 ℃ overnight to obtain a final product LaFe_0.5Cu_0.5O₃/0.1MoS₂。

(3) Shaped catalyst LaFe_0.5Cu_0.5O₃/0.1MoS₂Preparation of

The procedure was as in example 1.

(4) Catalyst LaFe_0.5Cu_0.5O₃/0.1MoS₂Degrading high COD fluorine-containing wastewater

The treatment process was the same as in example 1, wherein the initial COD of the high COD fluorine-containing wastewater was 7575mg/L, the fluoride ion concentration was 140mg/L, and the specific treatment results are shown in Table 4.

TABLE 4

Example 5

(1)LaFe_0.5Cu_0.5O₃Preparation of

According to a molar ratio of 1: 0.5: 0.5 lanthanum nitrate hexahydrate 2.1650g, ferric nitrate nonahydrate 1.0100g and cupric nitrate trihydrate 0.6040g were weighed and dissolved in 10mL of distilled water to obtain solution A. According to the molar ratio of the total molar amount of lanthanum, iron and copper metal ions to citric acid being 1: 1.0 2.1014g of citric acid and 0.05g of G-type foaming agent were weighed and dissolved in 40mL of distilled water to obtain solution B, and solution B was added dropwise to solution A by means of a peristaltic pump at a flow rate of 0.5mL/min, and the whole addition was carried out under stirring in a water bath at 85 ℃. Reacting to generate sol gel, drying the gel in a blast drying oven at 120 ℃ overnight, grinding to obtain precursor powder, heating the precursor powder to 600 ℃ at a speed of 5 ℃/min, keeping the temperature for 2h, then continuously heating to 800 ℃ at a speed of 5 ℃/min, keeping the temperature for 2h, and naturally cooling to obtain the LaFe monomer_0.5Cu_0.5O₃。

(2)LaFe_0.5Cu_0.5O₃/0.5MoS₂Preparation of

Mixing sodium molybdate dihydrate with L-cysteine according to the mass ratio of 1: 2 0.7558g of sodium molybdate dihydrate and 1.5115g of L-cysteine are respectively weighed out and dissolved in 60mL of isopropanol solution (50mL of isopropanol +10mL of water) with stirring, the pH is adjusted to 8 with 1mol/L of sodium hydroxide solution, and then 1g of LaFe monomer is added thereto_0.5Cu_0.5O₃Stirring for 45min, ultrasonically dispersing for 10min to obtain a mixture, transferring the mixture into a 100mL polytetrafluoroethylene reaction kettle, carrying out solvothermal reaction for 24h at 220 ℃, naturally cooling, washing with water and ethanol for three times respectively, and drying at 80 ℃ overnight to obtain a final product LaFe_0.5Cu_0.5O₃/0.5MoS₂。

(3) Shaped catalyst LaFe_0.5Cu_0.5O₃/0.5MoS₂Preparation of

The procedure was as in example 1.

(4)Catalyst LaFe_0.5Cu_0.5O₃/0.5MoS₂Degrading high COD fluorine-containing wastewater

The treatment process was the same as in example 1, wherein the initial COD of the high COD fluorine-containing wastewater was 7575mg/L, the fluoride ion concentration was 140mg/L, and the specific treatment results are shown in Table 5.

TABLE 5

Example 6

(1)LaFe_0.5Cu_0.5O₃Preparation of

According to a molar ratio of 1: 0.5: 0.5 lanthanum nitrate hexahydrate 2.1650g, ferric nitrate nonahydrate 1.0100g and cupric nitrate trihydrate 0.6040g were weighed and dissolved in 10mL of distilled water to obtain solution A. According to the molar ratio of the total molar amount of lanthanum, iron and copper metal ions to citric acid being 1: 1.5 weighing 3.1521g citric acid and 0.05gZ type foaming agent dissolved in 40mL distilled water to obtain solution B, dropping solution B into solution A by peristaltic pump at flow rate of 0.5mL/min, and stirring in 75 deg.C water bath. Reacting to generate sol gel, drying the gel in a blast drying oven at 120 ℃ overnight, grinding to obtain precursor powder, heating the precursor powder to 600 ℃ at a speed of 5 ℃/min, keeping the temperature for 2h, then continuously heating to 800 ℃ at a speed of 5 ℃/min, keeping the temperature for 2h, and naturally cooling to obtain the LaFe monomer_0.5Cu_0.5O₃。

(2)LaFe_0.5Cu_0.5O₃/0.3MoS₂Preparation of

Mixing ammonium molybdate and methionine according to a mass ratio of 1: 2 0.3674g of ammonium molybdate and 0.7347g of methionine were separately weighed out and dissolved in 60mL of an aqueous ethylene glycol solution (50mL of ethylene glycol +10mL of water) with stirring, the pH was adjusted to 8 with 1mol/L sodium hydroxide solution, and 1g of LaFe monomer was added thereto_0.5Cu_0.5O₃Stirring for 45min, ultrasonic dispersing for 15min to obtain mixture, transferring the mixture into 100mL polytetrafluoroethylene reaction kettle, performing solvothermal reaction at 200 deg.C for 24h, naturally cooling, washing with water and ethanol for three times respectively at 80 deg.CDrying overnight to obtain the final product LaFe_0.5Cu_0.5O₃/0.3MoS₂。

(3) Shaped catalyst LaFe_0.5Cu_0.5O₃/0.3MoS₂Preparation of

The procedure was as in example 1.

(4) Catalyst LaFe_0.5Cu_0.5O₃/0.3MoS₂Degrading high COD fluorine-containing wastewater

The treatment process was the same as in example 1, wherein the initial COD of the high COD fluorine-containing wastewater was 7575mg/L, the fluoride ion concentration was 140mg/L, and the specific treatment results are shown in Table 6.

TABLE 6

Example 7

(1)LaFe_0.5Cu_0.5O₃Preparation of

According to a molar ratio of 1: 0.5: 0.5 lanthanum nitrate hexahydrate 2.1650g, ferric nitrate nonahydrate 1.0100g and cupric nitrate trihydrate 0.6040g were weighed and dissolved in 10mL of distilled water to obtain solution A. According to the molar ratio of the total molar weight of lanthanum, iron and copper ions to ethanolamine being 1: 1.2 0.7330g of ethanolamine and 0.05g of G-type foaming agent were weighed and dissolved in 40mL of distilled water to obtain solution B, and solution B was added dropwise to solution A by a peristaltic pump at a flow rate of 0.5mL/min, and the whole dropwise addition was carried out under stirring in a water bath at 85 ℃. Reacting to generate sol gel, drying the gel in a forced air drying oven at 110 ℃ overnight, grinding to obtain precursor powder, heating the precursor powder to 600 ℃ at the speed of 5 ℃/min, keeping the temperature for 2h, then continuously heating to 800 ℃ at the speed of 5 ℃/min, keeping the temperature for 2h, and naturally cooling to obtain the LaFe monomer_0.5Cu_0.5O₃。

(2)LaFe_0.5Cu_0.5O₃/0.3MoS₂Preparation of

Ammonium heptamolybdate tetrahydrate and methionine in a mass ratio of 1: 2 separately 0.3309g of ammonium heptamolybdate tetrahydrate and 0.6618g of methionine were weighed out and dissolved in 60mL of an aqueous acetonitrile solution (50mL of ethyl acetate)Nitrile +10mL of water), dissolved with stirring, adjusted to pH 10 with 1mol/L sodium hydroxide solution, and then added with 1g of LaFe monomer_0.5Cu_0.5O₃Stirring for 45min, ultrasonically dispersing for 30min to obtain a mixture, transferring the mixture into a 100mL polytetrafluoroethylene reaction kettle, carrying out solvothermal reaction for 24h at 200 ℃, naturally cooling, washing with water and ethanol for three times respectively, and drying at 80 ℃ overnight to obtain a final product LaFe_0.5Cu_0.5O₃/0.3MoS₂。

(3) Shaped catalyst LaFe_0.5Cu_0.5O₃/0.3MoS₂Preparation of

The procedure was as in example 1.

(4) Catalyst LaFe_0.5Cu_0.5O₃/0.3MoS₂Degrading high COD fluorine-containing wastewater

The treatment process is the same as that of example 1, wherein the initial COD of the high-COD fluorine-containing wastewater is 7575mg/L, the fluorine ion concentration is 140mg/L, and the reaction time is prolonged to 4 h. The specific treatment results are shown in Table 7.

TABLE 7

Example 8

(1)LaFe_0.5Cu_0.5O₃Preparation of

According to a molar ratio of 1: 0.5: 0.5 lanthanum nitrate hexahydrate 2.1650g, ferric nitrate nonahydrate 1.0100g and cupric nitrate trihydrate 0.6040g were weighed and dissolved in 10mL of distilled water to obtain solution A. According to the molar ratio of the total molar amount of lanthanum, iron and copper metal ions to oxalic acid being 1: 1.2 1.0804g of oxalic acid and 0.05g of G-type foaming agent are weighed and dissolved in 40mL of distilled water to obtain solution B, the solution B is dripped into the solution A through a peristaltic pump at the flow rate of 0.5mL/min, and the whole dripping process is carried out under the stirring of a water bath at the temperature of 80 ℃. Reacting to generate sol gel, drying the gel in a forced air drying oven at 85 ℃ overnight, grinding to obtain precursor powder, heating the precursor powder to 600 ℃ at a speed of 5 ℃/min, keeping the temperature for 2h, then continuously heating to 800 ℃ at a speed of 5 ℃/min, keeping the temperature for 2h, naturally cooling, and then obtaining the final productObtaining monomer LaFe_0.5Cu_0.5O₃。

(2)LaFe_0.5Cu_0.5O₃/0.3MoS₂Preparation of

Mixing ammonium molybdate and methionine according to a mass ratio of 1: 2 0.3674g of ammonium molybdate and 0.7347g of methionine were separately weighed out and dissolved in 60mL of an aqueous isopropanol solution (50mL of isopropanol +10mL of water), stirred and dissolved, the pH was adjusted to 11 with 1mol/L of sodium hydroxide solution, and 1g of LaFe monomer was added thereto_0.5Cu_0.5O₃Stirring for 60min, ultrasonically dispersing for 10min to obtain a mixture, transferring the mixture into a 100mL polytetrafluoroethylene reaction kettle, carrying out solvothermal reaction for 24h at 200 ℃, then naturally cooling, washing with water and ethanol for three times respectively, and drying at 80 ℃ overnight to obtain a final product LaFe_0.5Cu_0.5O₃/0.3MoS₂。

(3) Shaped catalyst LaFe_0.5Cu_0.5O₃/0.3MoS₂Preparation of

The procedure was as in example 1.

(4) Catalyst LaFe_0.5Cu_0.5O₃/0.3MoS₂Degrading high COD fluorine-containing wastewater

The treatment process was the same as in example 1, wherein the initial COD of the high COD fluorine-containing wastewater was 15150mg/L, the fluoride ion concentration was 278mg/L, and the specific treatment results are shown in Table 8.

TABLE 8

Comparative example 1

(1)LaFeO₃Preparation of

According to a molar ratio of 1: 2.1650g of lanthanum nitrate hexahydrate and 2.0200g of ferric nitrate nonahydrate were weighed and dissolved in 10mL of distilled water to obtain solution A. According to the molar ratio of the total molar amount of lanthanum and iron metal ions to citric acid being 1: 1.2 weighing 2.5217g citric acid and 0.05gZ type foaming agent, dissolving in 40mL distilled water to obtain solution B, dripping solution B into solution A at flow rate of 0.5mL/min by peristaltic pump, and adding water at 80 deg.CStirring was carried out under bath. Reacting to generate sol gel, drying the gel in a forced air drying oven at 85 ℃, grinding to obtain precursor powder, heating the precursor powder to 600 ℃ at the speed of 5 ℃/min, preserving heat for 2h, continuing heating to 800 ℃ at the speed of 5 ℃/min, preserving heat for 2h, and naturally cooling to obtain the LaFeO monomer₃。

(2)LaFeO₃/0.3MoS₂Preparation of

Ammonium molybdate tetrahydrate and methionine are mixed according to the mass ratio of 1: 2 0.3674g of ammonium molybdate tetrahydrate and 0.7347g of methionine are respectively weighed out and dissolved in 60mL of ethylene glycol aqueous solution (50mL of ethylene glycol +10mL of water) with stirring, the pH is adjusted to 8 by 1mol/L of sodium hydroxide solution, and then 1g of LaFeO monomer is added₃Stirring for 60min, ultrasonically dispersing for 10min to obtain a mixture, transferring the mixture into a 100mL polytetrafluoroethylene reaction kettle, carrying out solvothermal reaction for 24h at 200 ℃, naturally cooling, washing with water and ethanol for three times respectively, and drying at 80 ℃ overnight to obtain a final product LaFeO₃/0.3MoS₂。

(3) Shaped catalyst LaFeO₃/0.3MoS₂Preparation of

The procedure was as in example 1.

(4) Catalyst LaFeO₃/0.3MoS₂Degrading high COD fluorine-containing wastewater

The treatment process was the same as in example 1, wherein the initial COD of the high COD fluorine-containing wastewater was 7575mg/L, the fluoride ion concentration was 140mg/L, and the specific treatment results are shown in Table 9.

TABLE 9

Comparative example 2

(1)LaFe_0.5Cu_0.5O₃Preparation of

According to a molar ratio of 1: 0.5: 0.5 lanthanum nitrate hexahydrate 2.1650g, ferric nitrate nonahydrate 1.0100g and cupric nitrate trihydrate 0.6040g were weighed and dissolved in 10mL of distilled water to obtain solution A. According to the molar ratio of the total molar amount of lanthanum, iron and copper metal ions to citric acid being 1: 1.2 weighing 2.5217g of citric acid and 0.05g of G-type foaming agent were dissolved in 40mL of distilled water to obtain solution B, and solution B was added dropwise to solution A at a flow rate of 0.5mL/min by means of a peristaltic pump, and the whole dropwise addition was carried out under stirring in a water bath at 80 ℃. Reacting to generate sol gel, drying the gel at 120 ℃ in a blast drying oven, grinding to obtain precursor powder, heating the precursor powder to 600 ℃ at a speed of 5 ℃/min, keeping the temperature for 2h, continuing heating to 800 ℃ at a speed of 5 ℃/min, keeping the temperature for 2h, and naturally cooling to obtain the LaFe monomer_0.5Cu_0.5O₃。

(2) Shaped monolithic LaFe_0.5Cu_0.5O₃Preparation of

The procedure was as in example 1.

(3) Catalyst LaFe_0.5Cu_0.5O₃Treating high COD fluorine-containing waste water

The treatment process was the same as in example 1, wherein the initial COD of the high COD fluorine-containing wastewater was 7575mg/L, the fluoride ion concentration was 140mg/L, and the specific treatment results are shown in Table 10.

Watch 10

Comparative example 3

(1)LaFe_0.5Cu_0.5O₃Preparation of

According to a molar ratio of 1: 0.5: 0.5 lanthanum nitrate hexahydrate 2.1650g, ferric nitrate nonahydrate 1.0100g and cupric nitrate trihydrate 0.6040g were weighed and dissolved in 10mL of distilled water to obtain solution A. According to the molar ratio of the total molar amount of lanthanum, iron and copper metal ions to citric acid being 1: 1.2 2.5217g of citric acid and 0.05g of G-type foaming agent were weighed and dissolved in 40mL of distilled water to obtain solution B, and solution B was added dropwise to solution A by means of a peristaltic pump at a flow rate of 0.5mL/min, and the whole dropwise addition was carried out in a water bath at 80 ℃ with stirring. Reacting to generate sol gel, drying the gel at 120 ℃ in a blast drying oven, grinding to obtain precursor powder, heating the precursor powder to 600 ℃ at a speed of 5 ℃/min, keeping the temperature for 2h, continuing heating to 800 ℃ at a speed of 5 ℃/min, keeping the temperature for 2h, and naturally cooling to obtain the LaFe monomer_0.5Cu_0.5O₃。

(2)LaFe_0.5Cu_0.5O₃/0.3MoS₂Preparation of

Ammonium molybdate tetrahydrate and methionine are mixed according to the mass ratio of 1: 2 0.3674g of ammonium molybdate tetrahydrate and 0.7347g of methionine were weighed out and dissolved in 60mL of an aqueous ethylene glycol solution (50mL of ethylene glycol +10mL of water), stirred and dissolved, the pH was adjusted to 10 with 1mol/L sodium hydroxide solution, and 1g of LaFe monomer was added thereto_0.5Cu_0.5O₃Stirring for 60min, ultrasonically dispersing for 10min to obtain a mixture, transferring the mixture into a 100mL polytetrafluoroethylene reaction kettle, carrying out solvothermal reaction for 24h at 200 ℃, naturally cooling, washing with water and ethanol for three times respectively, and drying at 80 ℃ overnight to obtain a final product LaFe_0.5Cu_0.5O₃/0.3MoS₂。

(3) Shaped catalyst LaFe_0.5Cu_0.5O₃/0.3MoS₂Preparation of

The procedure was as in example 1.

(4) Catalyst LaFe_0.5Cu_0.5O₃/0.3MoS₂Degrading high COD fluorine-containing wastewater

The treatment process is the same as that of example 1, wherein the initial COD of the high-COD fluorine-containing wastewater is 7575mg/L, the concentration of the fluorine ions is 140mg/L, and the influent water is heated without a heat exchanger, namely the reaction temperature is about 25 ℃. The specific treatment results are shown in Table 11.

TABLE 11

Comparative example 4

(1)MoS₂Preparation of

Mixing sodium molybdate dihydrate and thiourea according to a mass ratio of 1: 2 weighing 1.5115g sodium molybdate dihydrate and 3.0230g thiourea respectively, dissolving in 60mL ethylene glycol aqueous solution (50mL ethylene glycol and 10mL water), stirring for dissolving, adjusting pH to 7 with 1mol/L sodium hydroxide solution, stirring for 30min, ultrasonically dispersing for 5min, transferring the solution to a 100mL polytetrafluoroethylene reaction kettle, dissolving at 200 deg.CAfter the agent thermal reaction is carried out for 24 hours, the mixture is naturally cooled, washed by water and ethanol for three times respectively, and dried at 80 ℃ overnight to obtain the final product MoS₂。

(2) Molded monomer MoS₂Preparation of

The procedure was as in example 1.

(3) Monomer MoS₂Treating high COD fluorine-containing waste water

The treatment process was the same as in example 1, wherein the initial COD of the high COD fluorine-containing wastewater was 7575mg/L, the fluoride ion concentration was 140mg/L, and the specific treatment results are shown in Table 12.

TABLE 12

As can be seen by combining examples 1-8 and comparative examples 1-4, comparative example 1 is undoped modified LaFeO₃/0.3MoS₂When the catalyst is used for degrading the high-COD fluorine-containing wastewater, the treatment effect is only 45 percent, and the fluorine ion content is still 76mg/L, which shows that LaFeO which is not modified by doping copper₃/0.3MoS₂The medium copper ion can not exist in LaFeO in the form of interstitial ion₃In the crystal lattice, the transfer of current carriers is not facilitated, and hydrogen peroxide generated by OH cannot be effectively decomposed to catalyze and oxidize wastewater. Monomeric LaFe of comparative example 2_0.5Cu_0.5O₃When the catalyst is used for degrading high-COD fluorine-containing wastewater, the COD degradation rate is only 47%, and the fluorine ion effluent content is 72mg/L, which indicates that MoS does not exist₂Composite of (1), monomer LaFe_0.5Cu_0.5O₃The catalyst has the advantages of no large specific surface area, reduced adsorption performance, reduced active sites, no contribution to the formation of an acidic environment on the surface of the catalyst and the construction of iron ion microcirculation with different valence states, thus the effective decomposition of hydrogen peroxide can not be realized, and the removal rate of COD is not ideal. Comparative example 3 does not carry out heat exchange operation on the waste liquid, the COD degradation rate is only 34.02%, and the fluorine ion effluent water content is 91mg/L, which shows that the temperature is a key condition for determining the reaction rate, the degradation process is an exothermic reaction, and the normal temperature can not provide necessary energy, so that the reaction can not reach the required potential energy as soon as possible, and the catalytic reaction is causedThe chemical oxidation reaction rate is low, so that the high-COD fluorine-containing wastewater can not be efficiently degraded at normal temperature and normal pressure. Monomeric MoS of comparative example 4₂When the catalyst is used for degrading high-COD fluorine-containing wastewater, the COD degradation rate is only 12.30 percent, and the fluorine ion effluent content is 121mg/L, which shows that only monomer MoS exists₂The treatment effect on the high COD fluorine-containing wastewater is not ideal. The invention adopts the sol-gel method and the solvothermal method to prepare the LaFe with different doping ratios and composite ratios_(1-x)Cu_xO₃/YMoS₂The heterojunction type Fenton-like catalyst is prepared and molded and then used in the special wastewater treatment system for catalyzing and degrading the high-COD fluorine-containing wastewater, the COD removal rate can reach more than 65 percent, and the fluorine ion content is less than 10 mg/L.