Copper, sulfur eutectic lattice doped nano zero-valent iron, and preparation method and application thereof

Abstract

The application provides copper and sulfur co-lattice doped nano zero-valent iron and a preparation method and application thereof, and is based on the ironophilic and sulfurophilic properties of elements, successfully improves the copper content in the nano zero-valent iron lattice, changes the physicochemical properties, improves the stability and the removal capacity of trichloroethylene and florfenicol. When the material is synthesized, copper chloride is used as the copper source (sulfurophilic), iron trichloride is used as the iron source, and a sulfur source (sodium hydrosulfite) with ironophilic and sulfurophilic properties is added as a "bridge". Through a simple one-step method, the copper and sulfur co-lattice doped nano zero-valent iron material is synthesized by means of dissolution, mixing, stirring, drying and grinding. The crystal structure of the copper and sulfur co-lattice doped nano zero-valent iron material prepared by the application is complete, the copper and sulfur co-lattice are doped in the nano zero-valent iron, rather than forming copper elements on the surface of the iron. The sulfur content and electron transfer capacity of the copper and sulfur co-lattice doped nano zero-valent iron material are improved, and the material has superhydrophobicity. The stability of the material is significantly improved, that is, the life in water can reach more than 2 years, and after being exposed to air for 30 days, the material can maintain 80% of the zero-valent iron content and hydrophobicity. The material can also enhance the removal capacity of organic pollutants trichloroethylene and florfenicol in groundwater. The synthesis method provided by the application is simple and easy to operate, the material performance is significantly improved, can provide a new design idea for co-lattice doped iron-based nano materials, and can be applied to the remediation of contaminated groundwater.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of functional nanomaterials and technologies, and particularly relates to a copper and sulfur co-lattice doped nano zero-valent iron as well as a preparation method and application thereof. BACKGROUND

[0002] Nano zero-valent iron (nFe 0 ) has shown significant potential in environmental remediation, especially in the treatment of soil and groundwater pollutants, due to its excellent reduction capacity and high specific surface area. Numerous studies have shown that nFe 0 has special advantages in the separation and stabilization of pollutants such as organochlorides, inorganic anions, and heavy metals [Y. Z. Liu, et al. Nat. Nanotechnol. 16 (2021) 197-205; M. Li, et al. Appl. Catal. B 263 (2020) 118364; W. X. Zhang, et al. J. Nanopart. Res. 5 (2003) 323-332.]. However, nFe 0 also faces some challenges in practical applications, such as poor stability, easy aggregation, and easy passivation [X. H. Guan, et al. Water Res. 75 (2015) 224-248.], which increases its transportation and storage costs, reduces its dispersion in water, reaction activity with pollutants, and selectivity.

[0003] Modulating the crystal structure and coordination environment of iron-based metals is an emerging strategy that can break the trade-off between reaction activity and selectivity [D. Chen, et al. Environ. Sci. Technol. 57 (2023) 17178-17188.]. Recently, significant progress has been made in the lattice engineering of iron nanomaterials, which enhances the performance of materials by simultaneously adjusting the geometric structure and microenvironment of iron [X. H. Hu, et al. Nature Water 2 (2024) 84-92.]. In zero-valent iron (Fe 0 ) particles, the doping of heteroatoms can affect the body-centered cubic (BCC) crystal structure of Fe 0 and the coordination environment of central iron. For example, the doping of boron (B) or sulfur (S) can expand the Fe 0 lattice, which helps to release electrons, thereby accelerating electron transfer and enhancing reaction activity; at the same time, phosphorus (P) and S can induce Fe 0Nanocracks are generated in the particles, accelerating electron transfer and promoting reactivity. [J. H. Qu, et al. P. Natl. Acad. Sci. USA. 120 (2023) e2304552120; K. Wei, et al. Adv. Funct. Mater. 32 (2022) 2200498.]. But the actual doping amount of heteroatoms is easily limited, such as the sulfurized nanoscale zero-valent iron that was popular in the past decade, whose actual sulfur doping rate is only about one-third of the added amount (<37%) [J. Xu, et al. Accounts Mater. Res. 2 (2021) 420-431.].

[0004] Although there have been many modification measures for nFe 0 , such as bimetallic, sulfidation, surface coating, and composite with porous materials, few studies have been conducted on the modification of nFe 0 from the perspective of its elemental characteristics. Therefore, based on the Fe element of nFe 0 , this patent modifies it from the perspective of ferrophilia [A. G. Christy, et al. Eur. J. Mineral. 30 (2018) 193-204.], and introduces Cu element into the Fe lattice, which is strongly sulfurophilic and weakly ferrophilic, and significantly improves the lattice doping amount of Cu. Using copper chloride as the copper source and sodium hydrosulfite as the sulfur source, a copper and sulfur co-lattice doped nanoscale zero-valent iron material is synthesized by a simple one-step method. The material retains the crystal characteristics of nanoscale zero-valent iron and has superhydrophobicity; it increases the actual sulfur doping amount while improving the lattice copper amount; the change in elemental composition improves the electrical conductivity of the material itself. Therefore, whether it is the material's lifespan in water, stability in air, or reactivity and selectivity to trichloroethylene or florfenicol in groundwater, it has been significantly improved. In addition, copper can be almost fully doped, so there will be no additional copper pollution caused by the introduction of copper source, which reflects the green and environmentally friendly advantages of this design. In summary, this invention provides a new design idea and technical method for the lattice engineering modification of nanomaterials, especially iron-based nanomaterials. SUMMARY

[0005] The purpose of the present application is to overcome the shortcomings of the prior art and provide a copper and sulfur co-lattice doped nanoscale zero-valent iron and a preparation method and application thereof.

[0006] The purpose of the present application is achieved by the following technical solutions:

[0007] In a first aspect, the present application provides a preparation method of copper and sulfur co-lattice doped nanoscale zero-valent iron, comprising the following steps:

[0008] Step one: take anhydrous ferric chloride and dissolve it in deionized water to prepare a Fe 3+ stock solution;

[0009] Step two: take copper chloride dihydrate and dissolve it in deionized water to prepare a Cu 2+ stock solution;

[0010] Step three: mix the Fe 3+ stock solution prepared in step one and the Cu 2+ stock solution prepared in step two to prepare a metal mixed solution, in which the molar ratio of Cu 2+ to Fe 3+ is 0.01-0.1:1; the metal mixed solution is fully stirred at a rotation speed of 100-500 rpm under a nitrogen environment;

[0011] Step four: take sodium hydrosulfite and sodium borohydride according to a mass ratio of 0.02-0.35:1, and dissolve them in deionized water without oxygen to prepare a sulfur solution;

[0012] Step five: add the sulfur solution prepared in step four to the fully stirred metal mixed solution at a drop rate of 3-10 mL / min, the molar ratio of S 2- in the sulfur solution to Fe 3+ in the metal mixed solution is 0.14-0.28:1, the metal mixed solution is in a stirring state under a nitrogen environment during the drop process, and the reaction lasts for 15-30 min;

[0013] Step six: after the reaction is completed, the prepared material is separated by a magnet, and washed with deionized water without oxygen for 3 times;

[0014] Step seven: the material obtained in step six is dried under a vacuum at 30-80℃ for 4-12 h, and the dried material is obtained after the reaction lasts for 0-2 h after the material is cooled to 25℃;

[0015] Step eight: the dried material prepared in step seven is ground into powder to obtain copper and sulfur co-lattice doped nano zero-valent iron.

[0016] In a second aspect, the application further provides copper and sulfur co-lattice doped nano zero-valent iron.

[0017] In a third aspect, the application further provides an application of copper and sulfur co-lattice doped nano zero-valent iron, which can be used for efficient dehalogenation of trichloroethylene or florfenicol in groundwater.

[0018] Further, the application comprises the following steps:

[0019] (1) take actual groundwater as a reaction system to simulate actual groundwater pollution;

[0020] (2) injecting trichloroethylene or florfenicol into a closed anaerobic reaction bottle containing the groundwater which has been aerated and deoxidized to obtain a trichloroethylene or florfenicol contaminated solution;

[0021] (3) putting the copper and sulfur co-lattice doped nano zero-valent iron material into the closed anaerobic reaction bottle of step (2) which has contained the trichloroethylene or florfenicol contaminant;

[0022] (4) rotating the reaction bottle containing the material and the contaminant in step (3) on a rotator.

[0023] Further, the concentration of trichloroethylene in the trichloroethylene contaminated solution in step (2) is 76 μmol / L.

[0024] Further, the concentration of the florfenicol contaminated solution in step (2) is 0.15-0.3 mmol / L.

[0025] Further, the dosage of the copper and sulfur co-lattice doped nano zero-valent iron material in step (3) can be 0.5-2 g / L.

[0026] Further, the setting condition of the rotator in step (4) is 25℃, 30-80 rpm.

[0027] The beneficial effects of the present application are:

[0028] 1) The preparation method of the co-lattice doped nano zero-valent iron material is a one-step method, which is simple and easy to operate;

[0029] 2) The preparation method can simultaneously realize the doping of transition metal copper and sulfur;

[0030] 3) The method can significantly improve the actual sulfur doping amount of the co-lattice doped nano zero-valent iron;

[0031] 4) The method can significantly improve the amount of copper incorporated into the nano zero-valent iron lattice;

[0032] 5) The method will not cause copper pollution due to the introduction of copper salt;

[0033] 6) The material has superhydrophobicity while also improving its electrical conductivity;

[0034] 7) The stability of the material, including the life in water and air stability, is significantly improved;

[0035] 8) The material can enhance the removal capacity of trichloroethylene and florfenicol contaminants in groundwater. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 is a flow chart of a preparation method of copper and sulfur co-lattice doped nano zero-valent iron.

[0037] Figure 2 is an X-ray diffraction test pattern;

[0038] Figure 3 is a TEM morphology and elemental mapping;

[0039] Figure 4 is a plot of actual Cu / Fe and S / Fe molar ratios, wherein, Figure 4 (a) is a plot of actual Cu / Fe molar ratios, Figure 4 (b) is a plot of actual S / Fe molar ratios;

[0040] Figure 5 is a water contact angle plot;

[0041] Figure 6 is a fitted resistance plot;

[0042] Figure 7 is a water stability plot;

[0043] Figure 8 is an air stability plot;

[0044] Figure 9 is a plot of concentration versus time, wherein, Figure 9 (a) is a plot of concentration versus time of trichloroethylene in the reaction system, Figure 9 (b) is a plot of concentration versus time of florfenicol in the reaction system. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical scheme and advantages of the present application more clear and explicit, the present application is further described in detail in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application, but not all examples. Based on the examples in the present application, all other examples obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0046] The present application provides a preparation method of copper and sulfur co-crystal lattice doped nano zero-valent iron, comprising the following steps:

[0047] Step one: take anhydrous ferric chloride and dissolve it in deionized water to prepare a Fe 3+ stock solution;

[0048] Step two: take copper chloride dihydrate and dissolve it in deionized water to prepare a Cu 2+ stock solution;

[0049] Step three: mix the Fe 3+ stock solution prepared in step one and the Cu 2+The stock solution is mixed to form a metal mixed solution, in which the molar ratio of Cu 2+ and Fe 3+ is 0.01-0.1:1; the metal mixed solution is stirred sufficiently under nitrogen environment and using a rotating stirrer at a rotating speed of 100-500 rpm;

[0050] Step four: sodium dithionite and sodium borohydride are dissolved in oxygen-free deionized water at a mass ratio of 0.02-0.35:1 to obtain a sulfur solution;

[0051] Step five: the sulfur solution prepared in step four is added dropwise to the metal mixed solution stirred sufficiently at a drop rate of 3-10 mL / min, the molar ratio of S 2- in the sulfur solution to Fe 3+ in the metal mixed solution is 0.14-0.28:1, the metal mixed solution is in a stirring state under nitrogen environment during the dropwise addition, and the reaction is performed for 15-30 min;

[0052] Step six: after the reaction is completed, the prepared material is separated using a magnet and washed with oxygen-free deionized water for 3 times;

[0053] Step seven: the material obtained in step six is dried under vacuum at 30-80℃ for 4-12 h, and the dried material is obtained after the reaction is performed for 0-2 h after the material is cooled to 25℃;

[0054] Step eight: the dried material prepared in step seven is ground into powder to obtain copper and sulfur co-lattice doped nano zero-valent iron.

[0055] The application further provides an application of the copper and sulfur co-lattice doped nano zero-valent iron, and the copper and sulfur co-lattice doped nano zero-valent iron can be used for efficient dehalogenation of trichloroethylene or florfenicol in underground water.

[0056] The concentration of trichloroethylene in the trichloroethylene contaminated solution in step (2) is 76 μmol / L.

[0057] The concentration of the florfenicol contaminated solution in step (2) is 0.15-0.3 mmol / L.

[0058] The dosage of the copper and sulfur co-lattice doped nano zero-valent iron material in step (3) can be 0.5-2 g / L.

[0059] The rotating device in step (4) is set at 25℃ and 30-80 rpm.

[0060] Example 1: Preparation of copper and sulfur co-lattice doped nano zero-valent iron (1Cu-S-nFe 0 )

[0061] Step one: 57.93 g of anhydrous ferric chloride was dissolved in 1000 mL of deionized water to prepare a Fe 3+ stock solution with a concentration of 20 g / L;

[0062] Step two: 6.08 g of copper chloride dihydrate was dissolved in 500 mL of deionized water to prepare a Cu 2+ stock solution with a concentration of 12.10 g / L;

[0063] Step three: 100 mL of the Fe 3+ stock solution prepared in step one and 5 mL of the Cu 2+ stock solution prepared in step two were placed in a 1000 mL three-necked flask, 95 mL of deoxygenated deionized water was added to prepare a metal mixed solution; in the metal mixed solution, the molar ratio of Cu 2+ to Fe 3+ was 0.01:1; deoxygenation was continued under a nitrogen environment, and a rotating stirring rod was used to fully stir and mix at a speed of 400 rpm;

[0064] Step four: 6.8 g of sodium borohydride and 0.44 g of sodium hydrosulfite were dissolved in 200 mL of deoxygenated deionized water to obtain a sulfur solution;

[0065] Step five: the sulfur solution prepared in step four was added dropwise to the fully stirred and mixed metal mixed solution through a constant pressure funnel at a drop rate of 7 mL / min; the molar ratio of S 2- in the sulfur solution to Fe 3+ in the metal mixed solution was 0.14:1, and the metal mixed solution was in a stirring state under a nitrogen environment during the dropwise addition process, and the reaction was continued for 25 min;

[0066] Step six: after the reaction was completed, the prepared material was separated by a magnet and washed with deoxygenated deionized water for 3 times;

[0067] Step seven: the material obtained in step six was dried under vacuum at 60°C for 8 h, and after being cooled to 25°C, a slow oxidation reaction was carried out for 2 h to obtain a dried material;

[0068] Step eight: in an anaerobic glove box, the dried solid obtained in step seven was ground into a fine powder using a agate mortar and was packaged and stored, thereby obtaining a copper and sulfur co-crystal lattice doped nano zero-valent iron material.

[0069] The molar ratio of Cu 2+ to Fe 3+ in Example 1 was 0.01:1, so the copper and sulfur co-crystal lattice doped nano zero-valent iron prepared in this example was a low copper material, which was marked as 1Cu-S-nFe 0 .

[0070] Example 2 Preparation of copper, sulfur co-lattice doped nano zero-valent iron (10Cu-S-nFe) 0 ) of Example 2

[0071] Step one: 57.93 g of anhydrous ferric chloride was dissolved in 1000 mL of deionized water to prepare a Fe 3+ stock solution with a concentration of 20 g / L;

[0072] Step two: 6.08 g of copper chloride dihydrate was dissolved in 500 mL of deionized water to prepare a Cu 2+ stock solution with a concentration of 12.10 g / L;

[0073] Step three: 100 mL of the Fe 3+ stock solution prepared in step one and 50 mL of the Cu 2+ stock solution prepared in step two were taken into a 1000 mL three-necked flask, 50 mL of oxygen-free deionized water was added, and a metal mixed solution was prepared; in the metal mixed solution, the molar ratio of Cu 2+ to Fe 3+ was 0.1:1; deoxygenation was continuously carried out under a nitrogen environment, and a rotating stirring rod was used to fully stir and mix at a speed of 400 rpm;

[0074] Step four: 6.8 g of sodium borohydride and 0.44 g of sodium hydrosulfite were dissolved in 200 mL of oxygen-free deionized water to obtain a sulfur solution;

[0075] Step five: the sulfur solution prepared in step four was added dropwise into the fully stirred and mixed metal mixed solution through a constant pressure funnel at a drop rate of 7 mL / min; the molar ratio of S 2- in the sulfur solution to Fe 3+ in the metal mixed solution was 0.14:1, and the metal mixed solution was in a stirring state under a nitrogen environment during the dropwise addition process, and the reaction was carried out for 25 min;

[0076] Step six: after the reaction was completed, the prepared material was separated by a magnet and washed with oxygen-free deionized water for 3 times;

[0077] Step seven: the material obtained in step six was dried under vacuum at 60°C for 8 h, and after being cooled to 25°C, a slow oxidation reaction was carried out for 2 h to obtain a dried material;

[0078] Step eight: in an anaerobic glove box, the dried solid obtained in step seven was ground into a fine powder using a agate mortar and was packaged and stored, thereby obtaining copper, sulfur co-lattice doped nano zero-valent iron.

[0079] In Example 2, the molar ratio of Cu 2+ to Fe 3+The molar ratio is 0.1:1, therefore the copper-sulfur eutectic doped nano-zero-valent iron prepared in this embodiment is a high-copper material, labeled as 10Cu-S-nFe. 0 .

[0080] The methods for preparing copper-sulfur eutectic doped nano-zero-valent iron provided in Examples 1 and 2 are both one-step methods, and the flowcharts of the preparation methods are as follows: Figure 1 As shown, the obtained material is a copper-sulfur co-lattice doped nano-zero-valent iron material. Pure nano-zero-valent iron, copper-doped or sulfur-doped nano-zero-valent iron materials are prepared using the same method, the difference being whether or not Cu-containing materials are added. 2+ Stock solution or sulfur solution, and the addition of Cu 2+ The volume of the stock solution. The pure nano-zero-valent iron material is labeled as nFe. 0 Sulfur-doped nanomaterials of zero-valent iron are labeled as S-nFe 0 Low-copper-doped nanomaterials of zero-valent iron are labeled as 1Cu-nFe. 0 (Cu 2+ and Fe 3+ With a molar ratio of 0.01:1, the high copper-doped nanomaterial of zero-valent iron is labeled as 10Cu-nFe. 0 (Cu 2+ and Fe 3+ The molar ratio is 0.1:1.

[0081] Application Example 1: X-ray Diffraction (XRD) Test Experiment

[0082] The copper-sulfur eutectic lattice-doped nano-zero-valent iron (1Cu-S-nFe) prepared in Examples 1 and 2 were respectively compared. 0 and 10Cu-S-nFe 0 ) as well as pure nano-zero valent iron, single copper and sulfur-doped nano-zero valent iron materials (nFe) 0 1Cu-nFe 0 10Cu-nFe 0 and S-nFe 0 X-ray diffraction testing was performed, and the results are as follows: Figure 2 As shown.

[0083] from Figure 2 As can be seen, all nano-zero-valent iron materials retain Fe 0 Characteristic crystal form peaks. However, nano-zero-valent iron materials (1Cu-nFe) doped with copper or sulfur... 0 10Cu-nFe 0 S-nFe 0 1Cu-S-nFe 0 and 10Cu-S-nFe 0 Compared to pure nano-zero valent iron (nFe)0 ) peak position, slightly offset, and sulfur-doped nano zero-valent iron (S-nFe 0 , 1Cu-S-nFe 0 and 10Cu-S-nFe 0 ) peak position offset more obvious, indicating that copper and sulfur can be doped into the nFe 0 lattice, and sulfur has a greater impact on the nFe 0 lattice. Further comparison found that when the copper content is high (Cu 2+ and Fe 3+ molar ratio is 0.1:1), there will be a significant elemental copper peak in the absence of sulfur doping (10Cu-nFe 0 ), indicating that the amount of copper doped into the nFe 0 lattice is limited; but this situation is significantly improved when sulfur is co-doped (10Cu-S-nFe 0 ), almost no elemental copper peak, indicating that sulfur can help copper doped into the nFe 0 lattice and increase the amount of copper doped into the nFe 0 lattice. This result shows that based on the element characteristics, i.e. iron and sulfur affinity, it is feasible to modify the design of nano zero-valent iron; using sulfur with iron and sulfur affinity as a "bridge" to enhance copper with strong sulfur affinity and doped into the nFe 0 lattice is effective.

[0084] Application Example 2 Transmission Electron Microscope (TEM) Test Experiment

[0085] Transmission electron microscopy tests were performed on copper and sulfur co-lattice doped nano zero-valent iron (1Cu-S-nFe 0 and 10Cu-S-nFe 0 ) prepared by Example 1 and Example 2, respectively, and pure nano zero-valent iron, separately copper and sulfur-doped nano zero-valent iron materials (nFe 0 , 1Cu-nFe 0 , 10Cu-nFe 0 and S-nFe 0 ). High-angle annular dark field (HAADF) and X-ray energy dispersive spectroscopy (EDS) were used to image and analyze the material morphology and element distribution, and the results are shown in Figure 3 .

[0086] As can be seen from Figure 3 , the material morphology has no obvious change before and after copper or sulfur doping, and is irregular ellipsoidal, but the particle size is significantly larger when sulfur is doped. From the element distribution, although iron, copper and sulfur elements are uniformly distributed on the material particles, there is no sulfur doping (1Cu-nFe 0 and 10Cu-nFe 0), copper element still has distribution in the area without material; while with sulfur co-doping, copper element distribution almost only exists in the area of material particles (1Cu-S-nFe 0 and 10Cu-S-nFe 0 ). This result is consistent with the XRD test result, indicating that sulfur with both iron affinity and sulfur affinity can increase the amount of copper with strong sulfur affinity doped into nFe 0 lattice.

[0087] Application Example 3 Actual Cu / Fe molar ratio and actual S / Fe molar ratio test

[0088] The copper, sulfur co-lattice doped nano zero-valent iron (1Cu-S-nFe 0 and 10Cu-S-nFe 0 ) prepared by Example 1 and Example 2 respectively, and pure nano zero-valent iron, single copper and sulfur doped nano zero-valent iron material (nFe 0 , 1Cu-nFe 0 , 10Cu-nFe 0 and S-nFe 0 ) were dissolved in 10 mL aqua regia for digestion overnight, and after dilution with deionized water, they were sent to an inductively coupled plasma optical emission spectrometer (ICP-OES) for detection of copper, sulfur and iron element content, and the actual Cu / Fe molar ratio diagram is shown in Figure 4 (a), and the actual S / Fe molar ratio diagram is shown in Figure 4 (b).

[0089] From Figure 4 (a), it can be seen that the actual Cu / Fe molar ratio of the copper, sulfur co-lattice doped nano zero-valent iron is consistent with the theoretical Cu / Fe molar ratio when prepared, indicating that the added copper can be fully doped into the synthesized copper, sulfur co-lattice doped nano zero-valent iron; it is advisable to increase the lattice sulfur doping amount in nano zero-valent iron by introducing copper with strong sulfur affinity, and it will not cause copper pollution due to the addition of copper source in the synthesis process. Combined with the analysis results of XRD and TEM, it can be concluded that under the same copper doping amount, the amount of copper doped into the lattice can be increased by sulfur with both iron affinity and sulfur affinity. From Figure 4 (b), it can be seen that with the increase of the amount of copper with strong sulfur affinity doped, the actual S / Fe molar ratio in the copper, sulfur co-lattice doped nano zero-valent iron increases, indicating that the doping of copper can increase the lattice doping amount of sulfur, thereby reducing the ineffective consumption of sulfur reagent and the risk of sulfur reagent pollution.

[0090] Application Example 4 Water contact angle experiment

[0091] In an anaerobic glove box, a hydraulic tablet press was used to prepare copper, sulfur co-lattice doped nano zero-valent iron (1Cu-S-nFe0 and 10Cu-S-nFe 0 ) as well as pure nano-zero valent iron, single copper and sulfur-doped nano-zero valent iron materials (nFe) 0 1Cu-nFe 0 10Cu-nFe 0 and S-nFe 0 Thin sheets with a diameter of 6 mm were prepared and then dried under vacuum at 60°C for 8 hours. After cooling to 25°C, the sheets were removed and their water contact angles were quickly measured using a water contact angle meter to test the hydrophobicity of each material. The water contact angles of each material are shown below. Figure 5 As shown.

[0092] from Figure 5 As can be seen from this, compared to nFe 0 And single copper-doped nano-zero-valent iron materials (1Cu-nFe) 0 and 10Cu-nFe 0 The water contact angles of the remaining materials are all greater than 90°, and 1Cu-S-nFe 0 The water contact angle is greater than 150°, indicating that the copper-sulfur eutectic doped nano-zero-valent iron prepared in Examples 1 and 2 has good hydrophobic properties and is a hydrophobic material, which will have good selectivity for hydrophobic pollutants; and because 1Cu-S-nFe 0 It is a superhydrophobic material, and its lifespan in water and air stability should be significantly improved, which will help reduce transportation and storage costs.

[0093] Application Example 5: Electrochemical Experiment

[0094] 100 mg of the copper-sulfur eutectic doped nano-zero-valent iron (1Cu-S-nFe) prepared in Examples 1 and 2 were taken respectively. 0 and 10Cu-S-nFe 0 ) as well as pure nano-zero valent iron, single copper and sulfur-doped nano-zero valent iron materials (nFe) 0 1Cu-nFe 0 10Cu-nFe 0 and S-nFe 0 The electrode was placed on a titanium mesh and pressed onto it using a hydraulic press. The mesh was then removed and clamped onto the working electrode clamp. Electrochemical impedance spectroscopy (EIS) was performed in a three-stage battery using 10 mM NaCl as the electrolyte. The resistance results after fitting analysis of the test data are as follows: Figure 6 As shown.

[0095] from Figure 6 As can be seen, the resistance decreases significantly with the addition of copper or sulfur, and the co-doping of copper and sulfur (1Cu-S-nFe) further increases the resistance. 0and 10Cu-S-nFe 0 ) than the single copper or sulfur doped (1Cu-nFe 0 , 10Cu-nFe 0 and S-nFe 0 ) indicates that the copper and sulfur co-lattice doped nanoscale zero-valent iron materials (1Cu-S-nFe 0 and 10Cu-S-nFe 0 ) have better electrical conductivity and faster electron transfer rate, that is, the copper and sulfur co-doping endows the nanoscale zero-valent iron with higher electrocatalytic activity, which reflects the excellent electrical conductivity and activity advantage of the copper and sulfur co-lattice doped nanoscale zero-valent iron materials, and will be beneficial to the removal of pollutants.

[0096] Example 6 Water lifetime and air stability experiment

[0097] Water lifetime test: 100 mg of copper and sulfur co-lattice doped nanoscale zero-valent iron (1Cu-S-nFe 0 and 10Cu-S-nFe 0 ) prepared by Example 1 and Example 2 and pure nanoscale zero-valent iron, single copper and sulfur doped nanoscale zero-valent iron materials (nFe 0 , 1Cu-nFe 0 , 10Cu-nFe 0 and S-nFe 0 ) were respectively placed in a 170 mL reaction bottle containing 100 mL of oxygen-free deionized water, and after purging the headspace with nitrogen, the reaction bottle was sealed, then the reaction bottle was placed on a rotator, 500 μL of headspace gas was extracted at a predetermined time point for hydrogen detection, and finally the time length of the depletion of Fe 0 content in the material was calculated according to Fe 0 , that is, the water lifetime of the material.

[0098] Air stability: the remaining Fe 0 content and water contact angle change were taken as the indicators for air stability. 10 mg of copper and sulfur co-lattice doped nanoscale zero-valent iron (1Cu-S-nFe 0 and 10Cu-S-nFe 0 ) prepared by Example 1 and Example 2 and pure nanoscale zero-valent iron, single copper and sulfur doped nanoscale zero-valent iron materials (nFe 0 , 1Cu-nFe 0 , 10Cu-nFe 0 and S-nFe 0 ) were respectively dissolved in 10 mL of hydrochloric acid for 4-6 h digestion, after complete digestion, 500 μL of headspace gas was taken for hydrogen detection, and according to Fe 0 + HCl→ Fe 2+Fe content of the material, converted to H2 0 Fe content of the material, converted to H2 0 Fe content of the material, converted to H2 0 The water contact angle was tested in the same way as in Example 4, except that the material was changed to the material aged in air for different time.

[0099] It can be seen from Figure 7 that the longest life in water is the copper, sulfur co-lattice doped nano zero-valent iron material (1Cu-S-nFe 0 ), and the shortest is the copper doped nano zero-valent iron material alone (1Cu-nFe 0 ), which matches the hydrophobicity and electron transfer ability of the material. Although the electron transfer ability of 1Cu-S-nFe 0 and 1Cu-nFe 0 is improved compared with pure nano zero-valent iron material (nFe 0 ), and the electron transfer ability of 1Cu-S-nFe 0 is stronger than that of 1Cu-nFe 0 , but since 1Cu-S-nFe 0 is a super-hydrophobic material and 1Cu-nFe 0 is a hydrophilic material, the hydrophilic 1Cu-nFe 0 is easy to react with water and then be consumed by corrosion. Similarly, it can be seen from Figure 8 that the stability of 1Cu-S-nFe 0 in air is also improved due to its super-hydrophobicity. In the 30-day monitoring, the residual Fe 0 content and water contact angle change the least, it can save more than 80% of Fe 0 content and maintain hydrophobic properties, which shows that in transportation and storage, its environmental and storage conditions are not so harsh, which is conducive to reducing costs.

[0100] Example 7: Removal of trichloroethylene (TCE) and florfenicol (FF) in groundwater

[0101] 100 mg of copper, sulfur co-lattice doped nano zero-valent iron (1Cu-S-nFe 0 and 10Cu-S-nFe 0 ) prepared in Example 1 and Example 2, and pure nano zero-valent iron, nano zero-valent iron material doped with copper and sulfur alone (nFe 0 , 1Cu-nFe 0 , 10Cu-nFe 0 and S-nFe 0) were placed in 170 mL reaction bottles containing 100 mL anaerobic groundwater, purged with nitrogen gas and sealed, then 250 uL of TCE stock solution with a concentration of 27.8 mmol / L (mM) or 1 mL of FF stock solution with a concentration of 15 mM was injected to make the initial concentration of TCE 76 umol / L (μM) or the initial concentration of FF 0.15 mM, respectively, and then the reaction bottles were placed on a rotator. The changes of TCE and FF were detected at preset time points. For TCE, 100 μL of headspace gas was extracted for gas phase detection to detect residual TCE; for FF, 1 mL of liquid was extracted for liquid phase detection to detect residual FF, and the changes of the concentrations of TCE and FF during the reaction were as shown in Figure 9 (a) and Figure 9 (b).

[0102] As can be seen from Figure 9 (a) and Figure 9 (b), the concentrations of TCE and FF dropped the fastest in the reaction system of the copper-sulfur co-lattice doped nano zero-valent iron material (1Cu-S-nFe 0 ). Even in a relatively complex groundwater system, more than 80% of TCE can be removed by 1Cu-S-nFe 0 after 120 h of reaction; and for FF, almost 100% of FF can be completely removed by 1Cu-S-nFe 0 within 4 h, which embodies the advantages of copper-sulfur co-lattice doped nano zero-valent iron material in the treatment of TCE and FF contaminated groundwater and its practical application potential.

[0103] The above only describes the preferred embodiments of the present application and is not intended to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for preparing copper, sulfur eutectic lattice doped nano zero-valent iron, characterized in that, The method comprises the following steps: Step 1 : Take anhydrous ferric chloride and dissolve in deionized water to make Fe 3+ stock solution; Step two: take copper chloride dihydrate dissolved in deionized water, and make Cu 2+ stock solution; Step three: the Fe 3+ stock solution and Cu 2+ stock solution prepared in step two were mixed to form a metal mixed solution, in which Cu 2+ and Fe 3+ were in a molar ratio of 0.01-0.1:1; and the mixture was stirred sufficiently under a nitrogen atmosphere at a rotation speed of 100-500 rpm using a rotating stirrer. Step four: dissolve sodium hydrosulfite and sodium borohydride in deionized water in a mass ratio of 0.02-0.35:1 to obtain a sulfur solution; Step five: the sulfur solution prepared in step four is added to the mixed metal solution under stirring at a drop rate of 3-10 mL / min, the molar ratio of S 2- in the sulfur solution to Fe 3+ in the mixed metal solution is 0.14-0.28:1, the mixed metal solution is under stirring and in a nitrogen environment during the drop process, and the reaction is carried out for 15-30 min. Step six: after the reaction, separate the material by using a magnet and clean it with deionized water for 3 times; Step seven: dry the material obtained in step six under vacuum at 30-80℃ for 4-12h, and then cool it to 25℃ and react for 0-2h to obtain a dry material; Step eight: grind the dry material obtained in step seven into powder to obtain copper and sulfur co-lattice doped nano zero-valent iron.

2. Copper and sulfur co-lattice doped nano zero-valent iron prepared by the method of claim 1.

3. The use of copper, sulfur eutectic doped nano zero-valent iron according to claim 2, characterized in that, The copper and sulfur co-lattice doped nano zero-valent iron can be used for efficient dehalogenation of trichloroethylene or florfenicol in groundwater.

4. Use according to claim 3, characterized in that, The application comprises the following steps: (1) take actual groundwater as a reaction system to simulate actual groundwater pollution; (2) inject trichloroethylene or florfenicol into a sealed anaerobic reaction bottle containing groundwater that has been aerated and deoxygenated to obtain a trichloroethylene or florfenicol contaminated solution; (3) put the copper and sulfur co-lattice doped nano zero-valent iron material into the sealed anaerobic reaction bottle containing trichloroethylene or florfenicol pollutants in step (2); (4) put the reaction bottle containing the material and pollutants in step (3) on a rotator.

5. Use according to claim 4, characterized in that, The concentration of trichloroethylene in the trichloroethylene contaminated solution in step (2) is 76μmol / L.

6. Use according to claim 4, characterized in that, The concentration of the florfenicol contaminated solution in step (2) is 0.15-0.3mmol / L.

7. Use according to claim 4, characterized in that, The dosage of the copper and sulfur co-lattice doped nano zero-valent iron material in step (3) can be 0.5-2g / L.

8. Use according to claim 4, characterized in that, The setting conditions of the rotator in step (4) are 25℃ and 30-80rpm.

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