Textile solid waste-based bimetallic catalyst with multiple electron transport channels on surface, and construction method and application of textile solid waste-based bimetallic catalyst

Abstract

The invention belongs to the technical field of textile waste resource utilization and carbon fiber composite catalyst preparation, and provides a textile solid waste based bimetallic catalyst with multiple electron transmission channels on the surface and a construction method and application thereof. The preparation method comprises the following steps: by taking cotton and linen blended spinning solid waste as a raw material, uniformly mixing a bimetallic M1 / M2 salt solution, then mixing with an S source, dipping cotton cloth chippings, then carrying out hydro-thermal treatment, drying, and roasting in an inert atmosphere, and enabling the M1 / M2 bimetallic active component to pass through C-O / S-M1 / M2 and M1-S / O-M2 to form a dual-lean / rich electron center, and constructing a multiple electron transmission channel. The active bimetallic particles loaded on the surface of the prepared catalyst are uniformly dispersed, electron polarization distribution is enhanced, and electron transfer is more efficient. The catalyst can better adapt to complex conditions of wastewater, and shows ultrahigh catalytic degradation activity on various pollutants under different anion interferences and various environmental conditions. And organic matters can still be stably degraded after continuous operation for 720 minutes, so that the continuous treatment requirement is met.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of textile waste resource utilization and carbon fiber composite catalyst preparation, and specifically relates to a textile solid waste-based bimetallic catalyst with a surface multi-electron transport channel, a construction method thereof and application, and application of the catalyst in activating persulfate to efficiently degrade refractory organic pollutants (such as enrofloxacin, norfloxacin, bisphenol A, etc.) in wastewater, especially in continuous flow treatment of complex water environments and actual wastewater. BACKGROUND

[0002] China's textile industry is large in scale, with a total fiber processing volume accounting for more than 50% of the global total. However, the annual amount of waste and old textiles reaches 90 million tons, and the recycling rate is less than 20%. The existing recycling channels are not smooth, the industrial clusters are missing, and the added value of regenerated products is low. Traditional resource utilization methods mostly rely on chemical methods for graded extraction, which has the problems of complex separation steps, low utilization rate, and easy secondary pollution. Even some studies attempt to prepare carbon-based materials from textile solid waste, but mostly focus on biochar, which does not fully utilize the natural regular fiber skeleton structure, and often relies on petroleum-based raw materials, making it difficult to achieve the synergy of "pollution reduction and carbon reduction".

[0003] At the same time, wastewater discharged by the textile, pharmaceutical, and coking industries contains refractory and highly toxic emerging contaminants (ECs) such as sulfadiazine (SDZ) and enrofloxacin (ENR), which are difficult to be treated by conventional pretreatment technologies such as coagulation and adsorption. As an important branch of advanced oxidation processes (AOPs), heterogeneous Fenton-like technology has become a key direction for treating emerging contaminants due to its wide pH adaptability and easy separation and recovery. However, existing heterogeneous catalysts have obvious defects. They mostly rely on single metal sites or simple multi-metal mixing, and the metal particles are prone to agglomeration, have weak bonding with the carrier, and are easily dissolved out. In addition, due to the weak distribution of surface electron polarization and the lack of efficient electron transport channels, the oxidation of oxidizing agents is dependent on single metal valence, resulting in low utilization rate of oxidizing agents, limited reaction rate, and sensitivity to pH, which is greatly disturbed by anions in water bodies, making it difficult to adapt to the treatment needs of complex actual wastewater.

[0004] To break through the bottleneck of traditional Fenton-like technology, the double reaction center (DRCs) theory emerged as the times require. By constructing "poor electron center-rich electron center", it realizes degradation through the double pathways of pollutant electron donation and oxidant activation, which can reduce the consumption of oxidizing agents. However, existing DRCs research still has some shortcomings. Not only do they mostly use high-cost and difficult-to-scale pure substances such as graphene and MOFs as carriers, but they also lack application exploration of low-cost solid waste-based materials such as textile solid waste-derived carbon fibers. The electron channels are single, the electron transfer rate is limited, and the focus is on single metal loading, without utilizing the difference in electronegativity between bimetals to construct multiple poor / rich electron centers, which limits the improvement of catalytic performance.

[0005] Based on this, it is of great significance to develop a textile solid waste-based dual-metal catalyst with multiple electron transport channels constructed by dual-metal doping and non-metal regulation to realize low oxidant dosage and high stability of new pollutant degradation. SUMMARY

[0006] The first object of the present application is to provide a method for constructing a textile solid waste-based dual-metal catalyst with surface multiple electron transport channels, which solves the problems of easy agglomeration of metal particles in traditional single-metal or non-metal catalysts and low electron transfer efficiency caused by reliance on a single electron channel.

[0007] The second object of the present application is to provide the catalyst prepared by the above method, which realizes efficient conversion of textile solid waste and synergistic regulation of dual-metal and non-metal S doping.

[0008] The third object of the present application is to provide the application of the catalyst in activating persulfate to degrade antibiotics in refractory organic wastewater, which meets the requirements of adaptability and continuous flow treatment of complex water bodies.

[0009] To achieve the above objects, the present application is implemented by the following technical solution: a method for constructing a textile solid waste-based dual-metal catalyst with surface multiple electron transport channels, which uses cotton and linen blended textile solid waste as raw material, mixes dual-metal M1 / M2 salt solution according to a molar ratio range of 1:1 to 1.4:1, mixes with S source, impregnates cotton scraps, and then undergoes hydrothermal treatment, drying, and calcination in an inert atmosphere to prepare the catalyst; during the preparation process, the M1 / M2 dual-metal active components form dual-poor / rich electron centers through C-O / S-M1 / M2 and M1-S / O-M2, and multiple electron transport channels are constructed, i.e., the textile solid waste-based dual-metal catalyst with surface multiple electron transport channels; wherein: in the dual-metal salt solution, M1 is a cobalt salt solution, M2 is a molybdenum salt solution, and the S source is any one of thioacetamide, thiourea, and L-cysteine, with a final concentration range of S being 0.4-0.6 mol / L.

[0010] Further, the specific steps are as follows: (1) Textile solid waste pretreatment: select cotton and linen blended textile solid waste, cut into scraps for standby use; (2) Preparation of mixed solution and impregnation: dissolve cobalt salt and molybdenum salt in ultrapure water, mix well, add S source and stir for 30 min, then add textile solid waste scraps and continue stirring for 30 min, and finally uniformly add a dispersant with a concentration of 0.05-0.15 mol / L; (3) Hydrothermal reaction: place the above mixed system in a polytetrafluoroethylene liner, and perform hydrothermal reaction at 120-180℃ for 8-16h, and then dry in a forced air drying oven after the reaction is completed; (4) calcination process: the dried mixture is heated to 500-650 DEG C at a heating rate of 8 DEG C / min under inert atmosphere, and is kept for 0.8-1.2 h, and then is naturally cooled to obtain the textile solid waste-based bimetallic catalyst with surface multi-electron transport channels.

[0011] The cobalt salt is Co(NO3)2·6H2O, the molybdenum salt is Na2MoO4·6H2O, the molar ratio of Co(NO3)2·6H2O and Na2MoO4·6H2O is 1.3:1; the dispersing agent is any one of polyvinylpyrrolidone, vinyltriethoxysilane and triethoxysilane; and the inert gas is any one of nitrogen, argon or helium.

[0012] Further, the hydrothermal reaction temperature in step (3) is 160 DEG C, and the reaction time is 12 h. In step (4), the calcination process is to heat to 600 DEG C and keep for 1 h.

[0013] The application further provides the textile solid waste-based bimetallic catalyst with surface multi-electron transport channels obtained by the preparation method.

[0014] The catalyst retains the textile solid waste fiber skeleton structure, the bimetallic active component M1 / M2 is stably anchored on the surface of the carbon fiber through C-O / S-M1 / M2 and M1-S / O-M2, the bimetallic particles are uniformly distributed, form multiple electron channels, strengthen the distribution of electron polarization, and make the electron transmission more efficient.

[0015] The application further provides application of the textile solid waste-based bimetallic catalyst with surface multi-electron transport channels in activating persulfate PMS to degrade refractory organic pollutants in wastewater, wherein the wastewater is a single pollutant wastewater solution, or actual coking wastewater, pharmaceutical wastewater, mine wastewater or lake water, and the catalyst realizes continuous flow treatment of wastewater through a fixed bed reactor. The refractory organic pollutants are sulfadiazine SDZ, sulfamethoxazole SMX, carbamazepine CBZ, enrofloxacin ENR, norfloxacin NOR or bisphenol A BPA.

[0016] Further, the specific method is as follows: (1) in a 100 mL solution of 10-100 mg / L of refractory organic pollutants, a textile solid waste-based bimetallic catalyst with surface multi-electron transport channels is first added in an amount of 0.03-0.20 g / L, 0.1 M NaOH or H2SO4 is used to adjust the pH to 3-11, and then persulfate is added in an amount of 0.3-1.1 mmol / L; the mixed solution is placed in a constant-temperature water bath magnetic stirrer at 400 r / s for fully mixing and reaction, and the timing is started; (2) In a fixed time period, take 1 mL of the sample of the reaction, filter it through a 0.22 μm PES filter head, and then add it to a chromatographic bottle containing 0.5 mL of methanol for free radical quenching to terminate the reaction, and determine the concentration of organic pollutants in the sample by high performance liquid chromatography; when treating actual wastewater, additionally take 10 mL of the sample filtered through a 0.45 μm PES filter head, and determine the total organic carbon TOC and three-dimensional fluorescence spectrum 3D-EEM to evaluate the purification effect.

[0017] The present application aims at the problems that the annual output of textile solid waste is high, but the recycling rate is less than 20%, traditional disposal (such as landfill and incineration) is easy to cause resource waste and secondary pollution, and existing carbon-based catalysts mostly rely on complex component separation process or petroleum-based raw materials. A textile solid waste-based bimetallic catalyst with multiple surface electron transmission channels is prepared by taking widely available and low-cost cotton and hemp blended textile solid waste as the core raw material, and by the process of "bimetal (M1 / M2) and S source co-impregnation - hydrothermal treatment - simultaneous calcination in inert atmosphere". The process does not need complicated pretreatment, impurity removal or chemical component extraction of the textile solid waste, realizes high-value conversion of the textile solid waste, simultaneously completes bimetal loading and S doping, avoids pollution hidden dangers in the traditional solid waste resource utilization process, reduces the dependence on petroleum-based carrier raw materials, and takes into account environmental protection and economy.

[0018] Traditional single-metal or non-metal carbon-based catalysts generally have problems of easy agglomeration of metal particles and single electron transmission channel, which leads to insufficient exposure of active sites and low electron transmission efficiency, and it is difficult to efficiently activate oxidants. The present application relies on the regular structure of natural fibers of textile solid waste, and directional formation of C-O / S-M1 / M2 and M1-S / O-M2 multiple electron channels during preparation, which not only uniformly disperses bimetallic particles in the form of small particles on the surface of carbon fibers, but also firmly anchors the bimetal through chemical bonds, providing sufficient and efficient active sites for activation of persulfate (PMS).

[0019] The textile solid waste-based bimetallic catalyst with multiple surface electron transmission channels prepared by the present application has a significantly higher unpaired electron signal intensity on the surface than the control sample, and the multiple electron channels further strengthen the double reaction mechanism of "electron-poor center-electron-rich center", which greatly improves the degradation performance of refractory organic pollutants. Compared with the control system, the rate constant of degradation of sulfadiazine (SDZ) is increased by 16.16 times, and SDZ can be completely degraded within 12 min. Six types of new pollutants such as norfloxacin (NOR) and sulfamethoxazole (SMX) can be efficiently degraded within 30 min. At the same time, the catalyst has wide pH adaptability, and can efficiently degrade 10 mM Cl - , CO3² -When common anions exist in the water body, the degradation is not obviously interfered, and some anions can slightly promote the degradation; after the catalyst is used for 4 times, the activity can be recovered by calcination at 400 DEG C, and the degradation efficiency of methylene blue in the fixed bed reactor is still maintained above 95% after continuous operation for 720 minutes, which meets the requirements of complex actual water treatment and continuous flow application.

[0020] In summary, the textile solid waste based bimetallic catalyst with surface multi-electron transport channels is prepared from textile solid waste, which not only solves the problems of low resource utilization rate of textile solid waste and large pollution of traditional disposal, but also breaks through the bottleneck of low efficiency of electron transfer and poor environmental adaptability of traditional carbon-based catalysts, and meets the solid waste resource utilization and green low-carbon development goal; the catalyst preparation process is simple and low in cost, and the catalyst has high catalytic activity and strong stability, can effectively purify refractory organic matter in actual water bodies such as pharmaceutical wastewater and coking wastewater, and provides a feasible technical scheme for the collaborative development of water environment governance and high value of textile solid waste, and has important practical application value. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 SEM-EDS and TEM characterization graphs of the solid waste based bimetallic catalyst prepared in Example 1; in the graphs: a, b, d and e are SEM graphs, c is an SEM-EDS element surface scanning graph, f, g, i and j are TEM graph lattice stripe graphs, and h is a TEM-EDS element surface scanning graph; Figure 2 Linear sweep voltammetry (LSV) graphs of the solid waste based bimetallic catalyst and the control sample in Example 1; Figure 3 Electrochemical impedance spectroscopy (EIS) curve graphs of the solid waste based bimetallic catalyst and the control sample in Example 1; Figure 4 Electron paramagnetic resonance (EPR) spectrum of the solid waste based bimetallic catalyst and the control sample in Example 1; Figure 5 XPS graph of C 1s of the solid waste based bimetallic catalyst in Example 1; Figure 6 XPS graph of O 1s of the solid waste based bimetallic catalyst in Example 1; Figure 7 XPS graph of S 2p of the solid waste based bimetallic catalyst in Example 1; Figure 8 XPS graph of Co 2p of the solid waste based bimetallic catalyst in Example 1; Figure 9 XPS graph of Mo 3d of the solid waste based bimetallic catalyst in Example 1; Figure 10Three-dimensional fluorescence spectra of the actual wastewater treated by the reaction system of Example 8; in the figure: a, b are three-dimensional fluorescence spectra of the pharmaceutical wastewater raw water treated in the CMSCF / PMS system for 0, 30 min; c, d are three-dimensional fluorescence spectra of the coking wastewater raw water treated in the CMSCF / PMS system for 0, 30 min; e, f are three-dimensional fluorescence spectra of the mine wastewater raw water treated in the CMSCF / PMS system for 0, 30 min; g, h are three-dimensional fluorescence spectra of the lake raw water treated in the CMSCF / PMS system for 0, 30 min; Figure 11 The fixed bed reactor constructed by the solid waste-based bimetallic catalyst in Example 9 and the pollutant degradation performance diagram; in the figure: a is a structural schematic diagram of the fixed bed reactor; b is a physical diagram of the fixed bed reactor; c is a degradation efficiency curve of the fixed bed reactor for continuously treating 20 mg / L methylene blue (MB). DETAILED DESCRIPTION

[0022] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs, and references to the materials disclosed herein and to the materials cited in the references cited herein will be incorporated by reference.

[0024] The equivalent technologies of the described specific embodiments that can be understood by those skilled in the art through routine experiments are included in the present application.

[0025] In the following examples, the experimental methods are all routine methods unless otherwise specified. In the following examples, the instrument equipment used is all routine laboratory instrument equipment unless otherwise specified; in the following examples, the experimental materials used are all purchased from routine biochemical reagent stores unless otherwise specified.

[0026] Example 1: A method for preparing a textile solid waste-based bimetallic catalyst with a surface multi-electron transfer channel, specifically: (1) Textile solid waste pretreatment: cotton and linen blended textile solid waste is selected and cut into crumb for standby; (2) mixed solution preparation and impregnation: Co (NO3) 2.6H2O, Na2MoO4.6H2O are dissolved in ultrapure water according to the molar ratio of 1.3:1, ultrasonic mixing for 30 min, 0.5 mol / L thioacetamide (S source) is added and stirred for 30 min, then textile solid waste clippings are added and continue to stir for 30 min, finally 0.1 mol / L dispersant triethoxysilane is added and stirred for 12 h; (3) hydrothermal reaction: the above mixed system is placed in a polytetrafluoroethylene liner, and hydrothermal reaction is carried out at 160℃ for 12 h, and then drying is carried out in a blast drying oven; (4) calcination process: the dried mixture is placed in a tube furnace, and the temperature is raised to 600℃ at a heating rate of 8℃ / min under an inert atmosphere, and then heat treatment is carried out for 1 h, and then the catalyst CMSCF with surface multi-electron transport channels is obtained after natural cooling, filtration, washing and drying.

[0027] The inert gas is any one of nitrogen, argon or helium.

[0028] Meanwhile, in order to compare the performance of the textile solid waste-based bimetallic catalyst CMSCF, the catalysts CSCF without Mo, MSCF without Co, SCF without Co and Mo, and CMS without textile solid waste are prepared according to the above method.

[0029] The SEM-EDS and TEM characterization graphs of the obtained textile solid waste-based bimetallic catalyst with surface multi-electron transport channels are shown in Figure 1 The linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) curves are shown in Figure 2 The above figures show that the catalyst prepared by the textile waste of the application has a complete fiber skeleton, the bimetallic nanoparticles are uniformly dispersed after the addition of Co / Mo Figure 1 , form multiple electron channels, and accelerate the electron transfer rate in the reaction system Figure 2 .

[0030] The microstructure and morphology characteristics of CMSCF are analyzed by SEM. As shown in Figure 1 (a), (b), (d), (e), it can be seen that the carbon fiber surface of CMSCF grows in situ with flower-shaped metal particles, showing a morphology integrated with carbon fiber, which shows that metal Co and Mo are firmly embedded on the surface of carbon fiber, Co and Mo are combined with carbon fiber in multiple forms such as C-O / S-Co / Mo bond, this bonding mode not only can improve the stability of CMSCF, but also can promote the uniform dispersion of Co and Mo on the surface of carbon fiber, and reduce the agglomeration of metal. Figure 1The SEM-EDS of (c) shows that the five elements of C, O, S, Mo and Co are uniformly distributed on the CMSCF, further confirming the formation of C-O / S-Co / Mo bond. In Figure 1 The TEM-EDS of (h) further confirms that the five elements of C, O, S, Mo and Co are uniformly distributed on the CMSCF, consistent with the SEM-EDS results.

[0031] In order to further study the rate of electron transfer in the reaction system, LSV and EIS were used to study the electron transfer rate in the catalytic reaction system of CMSCF and the control group, as shown in Figure 2 , Figure 3 As shown in Figure 2 , it can be clearly observed that the LSV current response increases after the addition of PMS, indicating that PMS promotes electron transfer. When SDZ is added again, the LSV current response of CMSCF further increases, indicating that the added SDZ will participate in the reaction and accelerate the electron transfer rate. This result proves that in the electron transfer process on the surface of CMSCF, SDZ plays the role of electron donor, and the electrons in SDZ are transferred from the electron-poor carbon center to the electron-rich Co and Mo center through the C-O / S-Co / Mo electron channel and the Mo-S / O-Co electron channel.

[0032] Figure 3 The arc radius of EIS reflects the electron transfer rate, and it can be seen that the arc radius of CMSCF / PMS system is smaller than that of the control group. This indicates that the CMSCF / PMS system has a faster electron transfer rate, verifying that multiple electron transport channels are formed in CMSCF, accelerating the electron transfer rate in the reaction system.

[0033] In order to verify the electron transfer efficiency of the textile solid waste-based bimetallic catalyst with surface multiple electron transport channels, solid EPR test was carried out, as shown in Figure 4 . The standard unpaired electron signal was detected on the control group, indicating that unpaired electrons exist on the surface of the control group. However, a stronger unpaired electron signal was detected on CMSCF, indicating that more unpaired electrons are formed on CMSCF compared to the control group. The reason is that the doping of Co and Mo completely changes the electron distribution on the catalyst and directs the construction of multiple electron channels.

[0034] The surface element composition and surface metal valence of CMSCF were characterized by XPS. In Figure 5 The characteristic peaks of C-C / C=C and C-O / S were found in the C 1s fine spectrum of CMSCF, and the formed C-O / S bond laid the foundation for the C-O / S-Co / Mo electron channel; in Figure 6The C-O-Co / Mo characteristic peak at 531.98 eV between 531.06 eV (lattice oxygen) and 533.32 eV (surface oxygen) in the O 1s fine spectrum can improve the stability of Co / Mo and serve as an electron transmission bridge; Figure 7 The S 2p fine spectrum of CMSCF can be fitted into five single peaks. Figure 8 The Co 2p fine spectrum of CMSCF can be fitted into three characteristic peaks. 3 / 2 The characteristic peaks in the Co 2p fine spectrum can be attributed to the satellite peaks of Co 3+ , Co 2+ and Co, indicating that there are multiple valence states of cobalt in CMSCF, and that Co and Mo form lattice doping. Figure 9 The Mo 3d fine spectrum can be fitted into four characteristic peaks, and the Mo 3d fine spectrum shows that there are multiple valence states of Mo species in CMSCF.

[0035] In summary, the solid waste-based bimetallic catalyst CMSCF prepared by the application has a relatively complete carbon fiber structure, and the bimetallic doping is uniformly dispersed, the C-O / S-M1 / M2 and M1-S / O-M2 multiple electron channels are directionally constructed, and a large number of unpaired electrons exist on the surface. These characteristics synergistically act to help the solid waste-based bimetallic catalyst CMSCF to efficiently activate persulfate to degrade sulfadiazine (SDZ).

[0036] Experimental Example 1: Application of solid waste-based bimetallic catalyst CMSCF in activating PMS to degrade SDZ, the specific steps are as follows: (1) 100 mL of SDZ solution with a concentration of 100 μM was added to a 250 mL beaker, and solid waste-based bimetallic catalyst CMSCF was added, the catalyst dosage was controlled to be 0.05 g / L, 0.1 M NaOH or H2SO4 was used to adjust the solution pH to 6.06, and 0.4 mM persulfate (PMS) was added. The mixed solution was placed in a constant temperature water bath magnetic stirrer at 30°C and 400 r / s, and the reaction timing was started.

[0037] (2) At 0, 2, 5, 8, 12, 16, 20 and 30 min, 1 mL of reaction sample was taken with a disposable syringe, filtered through a 0.22 μm PES filter head, and then added to a 2 mL chromatographic bottle containing 0.5 mL of methanol (methanol was used to quench the free radicals in the system to terminate the reaction), and the concentration of SDZ in the sample was determined by a high performance liquid chromatograph (Wooking K2025) with a UV detector, and the SDZ degradation rate at different time points was calculated.

[0038] (3) After the degradation experiment is completed, the reaction solution is separated by suction filtration to separate the CMSCF catalyst, the catalyst is dispersed in 100 ml of ethanol by ultrasonic for 45 min, the adsorbed SDZ on the surface of the catalyst is eluted, the concentration of SDZ in ethanol is measured by high performance liquid chromatography, which is the adsorption amount of the catalyst; the actual concentration of the catalyst degrading SDZ is obtained by subtracting the remaining SDZ concentration in the solution from the total initial SDZ concentration and the adsorption amount. The results show that 100 μM SDZ is completely degraded within 12 min, and the degradation process is mainly catalytic oxidation, realizing rapid degradation of SDZ.

[0039] Comparative Example 1: The catalysts CSCF without Mo doping, MSCF without Co doping, and SCF without Co and Mo doping were used to activate persulfate to degrade sulfadiazine. Except that CSCF without Mo source, MSCF without Co source, and SCF without Co and Mo doping were not added, the remaining preparation steps and reaction conditions were consistent with the preparation and catalytic experiment of CMSCF in Example 1. The results are shown in Table 1, which shows that the degradation rate constant of CNTCF / PMS system on SDZ within 12 min is 16.16 times, 14.18 times, and 6.93 times that of SCF / PMS, MSCF / PMS, and CSCF / PMS system respectively.

[0040] Among them, the single metal catalysts CSCF without Mo doping, MSCF without Co doping, and SCF without Co and Mo doping of Comparative Example 1 are prepared by the following steps: Na2MoO4·6H2O (Mo source).

[0041] The preparation process of CSCF / MSCF / SCF is as follows: (1) Select cotton and hemp blended textile solid waste, cut into crumb for standby; (2) Preparation of CSCF: Co(NO3)2·6H2O (Co source) is dissolved in ultrapure water at a concentration of 0.02 mol / l, ultrasonic mixing for 30 min, 0.5 mol / L thioacetamide (S source) is added and stirred for 30 min, then textile solid waste crumb is added and stirred for 30 min, finally 0.1 mol / L triethoxysilane is added and stirred for 12 h.

[0042] Preparation of MSCF: Na2MoO4·6H2O (Mo source) is dissolved in ultrapure water at a concentration of 0.015 mol / l, ultrasonic mixing for 30 min, 0.5 mol / L thioacetamide (S source) is added and stirred for 30 min, then textile solid waste crumb is added and stirred for 30 min, finally 0.1 mol / L triethoxysilane is added and stirred for 12 h.

[0043] SCF preparation: 0.5 mol / L thioacetamide (S source) was added to the textile solid waste scraps and stirred for 30 min, and finally 0.1 mol / L triethoxysilane was added and stirred for 12 h; (3) Hydrothermal reaction: The above mixed system was placed in a polytetrafluoroethylene liner and hydrothermally reacted at 160°C for 12 h. After the reaction, the mixture was dried in a blast drying oven; (4) Calcination process: The dried mixture was placed in a tube furnace and heated to 600°C at a heating rate of 8°C / min under an inert atmosphere, and calcined for 1 h. After natural cooling, the mixture was filtered, washed and dried to obtain the solid waste-based bimetallic catalyst CSCF / MSCF / SCF.

[0044] Table 1: Comparison of catalytic ability of CMSCF / PMS system with CSCF / PMS, MSCF / PMS and SCF / PMS systems Experimental Example 2: The effect of different catalyst dosages on the removal rate of sulfadiazine (SDZ) in wastewater was investigated. The other steps and methods were the same as in Example 1, except that the catalyst dosage was different. The solid waste-based bimetallic catalyst CMSCF was prepared by the same method as in Example 1. The results are shown in Table 2. Even when the dosage of CMSCF was 0.01 g / L, the degradation rate of SDZ reached 99% in 30 min, further confirming the high catalytic performance of CMSCF.

[0045] Table 2: Effect of different dosages of catalyst CMSCF on the removal rate of SDZ in wastewater Experimental Example 3: The effect of different PMS dosages on the removal rate of sulfadiazine (SDZ) in wastewater was investigated. The other steps and methods were the same as in Example 1, except that the PMS dosage was different. The solid waste-based bimetallic catalyst CMSCF was prepared by the same method as in Example 1. The results are shown in Table 3. Even when the PMS concentration was 0.20 mM, the degradation rate of SDZ reached 79.89% in 30 min. When the PMS concentration was 0.30 mM, SDZ was completely degraded in 20 min, indicating that CMSCF had high activation ability for PMS.

[0046] Table 3: Effect of different PMS dosages on the removal rate of SDZ in wastewater Experimental Example 4: The influence of different initial sulfadiazine (SDZ) concentrations was investigated in the CMSCF system. Except for the different initial SDZ concentrations, the other steps and methods were the same as in Example 1, and the preparation of the solid waste-based bimetallic catalyst CMSCF was consistent with the preparation method in Example 1. The results are shown in Table 4. With the decrease of SDZ concentration, the degradation rate gradually increased. SDZ of 20 µM was completely degraded within 5 min. Even 100 µM SDZ could achieve a degradation rate of 95.88% within 30 min.

[0047] Table 4: Influence of different initial sulfadiazine (SDZ) concentrations on SDZ removal rate in wastewater Experimental Example 5: The degradation performance of CMSCF for SDZ under different anion interference was investigated. Except for the addition of 10 mM / L CO3 2- , HCO3 - , Cl - , SO4 2- coexisting anions in the water body, the other steps and methods were the same as in Example 1, and the preparation of the solid waste-based bimetallic catalyst CMSCF was consistent with the preparation method in Example 1. The results are shown in Table 5. After adding 10 mM of Cl - , CO3 2- and HCO 3- , the degradation of SDZ by the CMSCF / PMS system was not only not inhibited, but also slightly promoted the degradation of SDZ, while the addition of 10 mM SO4 2- slightly inhibited the degradation of SDZ.

[0048] Table 5: Influence of different anions on SDZ removal rate in wastewater Experimental Example 6: The degradation performance of CMSCF for different organic pollutants was investigated. Except for the different organic pollutants to be degraded, the other steps and methods were the same as in Example 1, and the preparation of the solid waste-based bimetallic catalyst CMSCF was consistent with the preparation method in Example 1. The results are shown in Table 7. The CMSCF / PMS system had good degradation performance for sulfamethoxazole (SMX), carbamazepine (CBZ), enrofloxacin (ENR), norfloxacin (NOR), and bisphenol A (BPA), and could achieve complete degradation within 30 min. The CMSCF exhibited the best catalytic performance for CBZ. The degradation results of these six different types of pollutants confirmed that the CMSCF had good universality and high catalytic capacity.

[0049] Table 7: Degradation performance of CNTCF for different organic pollutants Experimental Example 7: The purification ability of CMSCF on actual wastewater was investigated, and the changes of the actual wastewater in the purification process were analyzed by three-dimensional fluorescence spectroscopy, and the results are shown in Figure 10 The preparation of CMSCF was consistent with the preparation method in Example 1. Figure 10 (a-b) are 3D-EEM of the pharmaceutical wastewater before and after 30 min treatment in the CMSCF / PMS system, respectively. It can be found that the Ex 250-300 nm, Em 300-450 nm fluorescence peak of the raw water corresponds to antibiotics and intermediates, conjugated aromatic substances, and the peak intensity significantly decreases after 30 min treatment, and the substance concentration decreases, and the system has good purification effect; Figure 10 (c-d) are 3D-EEM of the coking wastewater before and after 30 min treatment in the CMSCF / PMS system, respectively. According to the position of the characteristic peak in the coking wastewater, it can be found that the coking wastewater is rich in aromatic hydrocarbon derivatives and humic acid, and the peak intensity decreases after treatment, and the polycyclic aromatic hydrocarbon and phenolic signal decreases; Figure 10 (e-f) are 3D-EEM of the mine wastewater before and after 30 min treatment in the CMSCF / PMS system, respectively. It can be found from the figure that the Ex 300-400 nm, Em 400-500 nm is dissolved organic matter (DOM), and the Ex 200-280 nm, Em 250-350 nm is phenol, and the peak intensity decreases after treatment, and the content of DOM and phenol decreases, and the system can purify the contaminated mine wastewater; Figure 10 (g-h) are 3D-EEM of the lake water before and after 30 min treatment in the CMSCF / PMS system, respectively. According to the position of the fluorescence peak in the lake water, it can be found that the lake water contains fulvic acid and protein in DOM, and the peak intensity decreases after treatment, and the content of such substances decreases, and the system can purify the natural organic pollutants in the lake water.

[0050] Experimental Example 8: The catalytic stability of CMSCF was investigated, and the continuous flow catalytic degradation performance of CMSCF / PMS system was detected by building a fixed bed reaction, as shown in Figure 11The figure a is a schematic diagram of pollutant degradation in a fixed bed reactor. 0.3 g of CMSCF is added in the fixed bed reactor, and quartz wool and glass beads are added as fillers in the upper and lower layers to prevent the loss of CMSCF; the figure b is a continuous degradation reaction of 20 mg / L methylene blue in an actual fixed bed reactor, 20 mg / L methylene blue and 0.4 mM PMS are mixed after the pump, and the continuous flow experiment is carried out at a pump speed of 5 revolutions; the figure c is the degradation efficiency of rhodamine B in the continuous flow reactor within 720 min, the experimental results show that the continuous flow reactor can achieve more than 95% methylene blue degradation efficiency within 720 min, which shows long-term stability, and further verifies that CMSCF is a stable and efficient Fenton-like water treatment catalyst.

[0051] Finally, it should be pointed out that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for constructing a textile solid waste based bimetallic catalyst for surface multi-electron transfer channel, characterized by: The textile solid waste is used as raw material, a bimetallic M1 / M2 salt solution is mixed with a S source in a molar ratio of 1:1-1.4:1, and then the mixture is impregnated into cotton cloth scraps, and then the impregnated cotton cloth scraps are subjected to hydrothermal treatment, drying, and calcination in an inert atmosphere to obtain the textile solid waste-based bimetallic catalyst with a surface multi-electron transfer channel.

2. A method of constructing a textile solid waste based bimetallic catalyst for surface multi-electron transfer channel according to claim 1, characterized by: The specific steps are as follows: (1) Textile solid waste pretreatment: select cotton and hemp blended textile solid waste, and cut it into scraps for standby use; (2) Preparation of mixed solution and impregnation: dissolve cobalt salt and molybdenum salt in ultrapure water, mix them, add a S source, stir for 30 min, then add textile solid waste scraps and continue to stir for 30 min, and finally add a dispersant with a concentration of 0.5-0.15 mol / L; (3) Hydrothermal reaction: place the above-mentioned mixed system in a polytetrafluoroethylene liner, and subject it to hydrothermal reaction at 120-180℃ for 8-16 h, and then dry it in a blast drying oven; (4) Calcination process: heat the dried mixture to 500-650℃ at a heating rate of 8℃ / min in an inert atmosphere, and then calcine it for 0.8-1.2 h, and then naturally cool it to obtain the textile solid waste-based bimetallic catalyst with a surface multi-electron transfer channel.

3. A method of constructing a textile solid waste based bimetallic catalyst for surface multi-electron transfer channel according to claim 2, characterized in that: The cobalt salt is Co(NO3)2·6H2O, the molybdenum salt is Na2MoO4·6H2O, and the molar ratio of Co(NO3)2·6H2O to Na2MoO4·6H2O is 1.3:1; the dispersant is any one of polyvinylpyrrolidone, vinyltriethoxysilane, and triethoxysilane; and the inert gas is any one of nitrogen, argon, or helium.

4. The method of constructing a textile solid waste based bimetallic catalyst for surface multi-electron transfer channel according to claim 2, wherein: The hydrothermal reaction temperature in step (3) is 160℃, and the reaction time is 12 h.

5. The method of constructing a textile solid waste based bimetallic catalyst for surface multi-electron transfer channel according to claim 2, wherein: In step (4), the calcination process is heating to 600℃ and holding for 1 h.

6. The textile solid waste-based bimetallic catalyst with a surface multi-electron transfer channel obtained by the preparation method of any one of claims 1-5.

7. Use of the textile solid waste based bimetallic catalyst of surface multi-electron transfer channel according to claim 6 for the activation of persulfate salt (PMS) for the degradation of recalcitrant organic pollutants in wastewater, characterized in that: The wastewater is a single pollutant wastewater solution, or an actual coking wastewater, a pharmaceutical wastewater, a mine wastewater, or lake water, and the catalyst is used for continuous flow treatment of wastewater through a fixed bed reactor. The refractory organic pollutants are sulfadiazine SDZ, sulfamethoxazole SMX, carbamazepine CBZ, enrofloxacin ENR, norfloxacin NOR, or bisphenol A BPA.

8. Use according to claim 7, characterized in that: The specific method is as follows: (1) In 100 mL of 10-100 mg / L of refractory organic pollutants solution, first add textile solid waste-based bimetallic catalyst with surface multi-electron transfer channel, the addition amount is 0.03-0.20 g / L, adjust the pH to 3-11 with 0.1 M NaOH or H2SO4, then add persulfate, the addition amount is 0.3-1.1 mmol / L, put the mixed solution in a constant temperature water bath magnetic stirrer with 400 r / s for fully mixing reaction, start timing; (2) In a fixed time period, take 1 mL of the reaction sample, filter it through a 0.22 μm PES filter head, then add it to a chromatographic bottle containing 0.5 mL of methanol for free radical quenching to terminate the reaction, and use high performance liquid chromatography to determine the concentration of organic pollutants in the sample; when treating actual wastewater, additionally take 10 mL of sample, filter it through a 0.45 μm PES filter head, and measure the total organic carbon TOC and three-dimensional fluorescence spectrum 3D-EEM to evaluate the purification effect.

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