Preparation method and application of nZVCu@AF composite material

Abstract

The application provides a preparation method of an nZVCu@AF composite material and application thereof, and comprises the following steps: under the protection of nitrogen, equal-volume-ratio 0.01-0.1M Cu(II) solution and 0.2-2.0M potassium borohydride solution are simultaneously added drop by drop into amyloid fiber suspension liquid, the volume ratio of the dropwise added solution to the amyloid fiber suspension liquid is 1:2, and the obtained material is sufficiently stirred and reacted for 2-6h; the obtained material is repeatedly washed with ultrapure water to remove impurities, and then vacuum freeze-dried to obtain the nZVCu@AF composite material. The application solves the problems that organic phosphorus compounds are difficult to degrade and have low mineralization rate, and constructs a one-step deep treatment method for water body organic phosphorus, which can efficiently induce inorganic conversion of organic phospholipid and realize in-situ phosphorus recovery.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of environmental protection, and particularly relates to a preparation method of nZVCu@AF composite material (nano zero-valent metal modified amyloid fiber) and application thereof to in-situ induced conversion and removal of organic phosphorus in water. BACKGROUND

[0002] In recent years, organic phosphorus compounds are widely used as scale inhibitors and chelating agents in industrial production processes such as electroplating, textile and papermaking, and a large amount of organic phosphorus contaminated wastewater is generated. This kind of wastewater has the characteristics of being difficult to degrade and having strong biological toxicity, which leads to poor phosphorus removal effect of traditional water treatment processes. At present, the treatment strategy for organic phosphorus wastewater mainly uses advanced oxidation technology to oxidize and degrade organic phosphorus in water into inorganic phosphorus, and then combines with adsorption, chemical precipitation and other methods to realize the deep treatment of phosphorus contaminated wastewater. However, organic phosphorus compounds have complex structure and stable properties, and are difficult to degrade. The mineralization rate of traditional advanced oxidation technology for organic phosphorus is low, and the conversion rate of inorganic phosphorus is only 10-15%, so it is difficult to realize deep treatment in the subsequent treatment process.

[0003] A preparation method of amyloid fiber iron oxide composite membrane and a method for removing phosphate in tail water of a municipal sewage treatment plant are disclosed in Chinese patent CN 113289502. The composite amyloid fiber membrane is prepared by a vacuum filtration method using a 10 nm or less iron oxide amyloid fiber composite adsorption material and natural diatomite as a supporting layer. The phosphorus content in the effluent can be reduced to below the safety standard. However, the fiber membrane only has good adsorption and separation effect on inorganic phosphate in water, and has poor removal effect on common organic phosphorus pollutants in industrial wastewater, and can only be used for deep treatment after the mineralization of organic phosphorus wastewater.

[0004] At present, the deep treatment technology for organic phosphorus contaminated wastewater is a two-stage combined process, which has a complex process flow and high treatment cost. SUMMARY

[0005] The application provides a preparation method of nZVCu@AF composite material and application thereof, and aims to solve the problems of difficult degradation of organic phosphorus compounds and low mineralization rate of existing methods, and to construct a one-step deep treatment method for organic phosphorus in water, which can efficiently induce the inorganic conversion of organic phosphorus and realize in-situ phosphorus recovery.

[0006] TECHNICAL SCHEME

[0007] The application provides a preparation method of an nZVCu@AF composite material, and comprises the following steps: under the protection of nitrogen, equal-volume 0.01-0.1M Cu(II) solution and 0.2-2.0M potassium borohydride solution are added into amyloid fiber suspension liquid drop by drop at the same time, the volume ratio of the dropwise added solution to the amyloid fiber suspension liquid is 1:2, the reaction is carried out for 2-6 hours under sufficient stirring, and the obtained material is washed repeatedly with ultrapure water to remove impurities, and then vacuum freeze-drying is carried out to obtain the nZVCu@AF composite material.

[0008] Preferably, the concentration of the Cu(II) solution is 0.05-0.08M, and the concentration of the potassium borohydride solution is 1.0-2.0M.

[0009] Preferably, the preparation method of the amyloid fiber suspension liquid is that: a 0.25-2.5g / mL β-lactoglobulin aqueous solution is prepared by adjusting the pH to 2-5, and then the solution is placed in a 70-120°C water bath and magnetically stirred for 5-10 hours.

[0010] Preferably, the concentration of the β-lactoglobulin aqueous solution is 0.5-1.0g / mL.

[0011] Preferably, the dropwise adding speed is 0.5-2mL / min.

[0012] The application further provides an application of the nZVCu@AF composite material prepared by the preparation method of the nZVCu@AF composite material in the deep treatment of organic phosphorus wastewater.

[0013] Further, the application method is as follows:

[0014] The nZVCu@AF catalysis-adsorption material, hydrogen peroxide and organic phosphorus wastewater are oscillated at room temperature, the mass ratio of the nZVCu@AF, the hydrogen peroxide and the organic phosphorus wastewater is 1:5:1000-10000, the reaction time is 2-12 hours, the mineralization-adsorption reaction of hydroxyethane diphosphonic acid, tetrahydroxy methyl sulfuric acid phosphorus or tris (2-carboxyethyl) phosphine in the organic phosphorus wastewater is carried out, and thus the hydroxyethane diphosphonic acid, the tetrahydroxy methyl sulfuric acid phosphorus or the tris (2-carboxyethyl) phosphine in the wastewater is removed.

[0015] Further, before the nZVCu@AF catalysis-adsorption material and the hydrogen peroxide are added into the organic phosphorus wastewater, the pH of the organic phosphorus wastewater is adjusted to 3.0-10.0.

[0016] Preferably, before the nZVCu@AF catalysis-adsorption material and the hydrogen peroxide are added into the organic phosphorus wastewater, the pH of the organic phosphorus wastewater is adjusted to 7.0-8.0.

[0017] Overall, compared with the prior art, the above technical solutions conceived by the present application mainly have the following technical advantages:

[0018] (1) In the nZVCu@AF composite material, sub-10 nm zero-valent copper particles with high dispersity and extremely high reactivity can be formed, thus having excellent catalytic performance, being able to effectively catalyze H2O2 to generate hydroxyl radicals, high-valence copper and other active substances, and oxidize and degrade organic phosphorus pollutants in water.

[0019] (2) The Cu species formed in the catalytic reaction process can be complexed with organic phosphorus through coordination, and then through its own oxidation-reduction effect, excite intramolecular electron transfer of the organic phosphorus pollutants, destroy the stable C-P bond in the organic phosphorus compounds, thereby reducing the structural stability of the organic phosphorus molecules and strengthening the inorganic mineralization process thereof.

[0020] (3) The inorganic phosphate produced after the mineralization of the organic phosphorus can be further in-situ adsorbed and recovered by the nZVCu@AF through surface coordination, electrostatic attraction and other effects, without the need for secondary treatment with other technologies.

[0021] (4) The method not only can realize deep treatment of organic phosphorus pollution, but also has good Cu species fixing performance, good adsorption performance of amyloid fibers to copper ions, and in-situ growth of copper phosphate in the phosphorus removal reaction process, effectively inhibiting the elution of copper ions, ensuring efficient, green and pollution-free treatment process. (5) The method described in the present application can efficiently mineralize various water-borne refractory organic phosphorus pollutants, including hydroxyethylidene diphosphonic acid HEDP (90%-99%), tetrahydroxymethyl phosphoric acid THPS (84%-93%) and tris (2-carboxyethyl) phosphine TCEP (80%-91%), and simultaneously realize in-situ adsorption and recovery of inorganic phosphate, with an adsorption capacity of 3.9-37.3 mg / g. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The SEM image of nZVCu@AF, (a) is a 7.0k magnification image, and (b) is a 10.0k magnification image.

[0023] Figure 2 The XRD spectrum of nZVCu@AF. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and application advantages of the present application more clear and explicit, the following will be further described in detail in combination with the drawings and examples. It should be understood that the specific embodiments depicted herein are only used to explain the present application and are not used to limit the present application. In addition, the technical features involved in each embodiment of the present application described below can be combined with each other as long as they do not conflict with each other.

[0025] Example 1

[0026] Take 2.0 g of β-lactoglobulin powder dissolved in 200 mL of ultrapure water, adjust pH = 2, put in 90 ℃ water bath, magnetic stirring for 6 h, prepared into amyloid fibril suspension; Under the protection of nitrogen with a purity of 99.5%, 50 mL of 0.08 M Cu(II) solution and 50 mL of 2.0 M potassium borohydride solution were added dropwise into the above suspension at a drop rate of 2 mL / min, and fully stirred for 2 h. The obtained material was repeatedly washed with ultrapure water to remove impurities and vacuum freeze-dried to prepare nZVCu@AF composite material.

[0027] The prepared nZVCu@AF composite material was used for deep treatment of simulated organic phosphorus contaminated wastewater, and the steps were as follows: 50 mL conical flask was used as reactor, simulated wastewater was HEDP solution, 50 mL of organic phosphorus wastewater, 0.01 g of nZVCu@AF and 0.05 mL of 30% H2O2 were added into the reactor, the reactor was placed in a table type constant temperature oscillation incubator for reaction, the rotation speed was 200 rpm, the temperature was 25 ℃, the mineralization rate of organic phosphorus was calculated after 0.5 h of reaction, and the removal rate of phosphate in water was calculated after 24 h of reaction.

[0028] Example 2

[0029] Take 2.0 g of β-lactoglobulin powder dissolved in 200 mL of ultrapure water, adjust pH = 2, put in 90 ℃ water bath, magnetic stirring for 6 h, prepared into amyloid fibril suspension; Under the protection of nitrogen with a purity of 99.5%, 50 mL of 0.08 M Cu(II) solution and 50 mL of 2.0 M potassium borohydride solution were added dropwise into the above suspension at a drop rate of 2 mL / min, and fully stirred for 2 h. The obtained material was repeatedly washed with ultrapure water to remove impurities and vacuum freeze-dried to prepare nZVCu@AF composite material.

[0030] The prepared nZVCu@AF composite material was used for deep treatment of simulated organic phosphorus contaminated wastewater, and the steps were as follows: 50 mL conical flask was used as reactor, simulated wastewater was HEDP solution, 50 mL of organic phosphorus wastewater, 0.01 g of nZVCu@AF and 0.05 mL of 30% H2O2 were added into the reactor, the reactor was placed in a table type constant temperature oscillation incubator for reaction, the rotation speed was 200 rpm, the temperature was 25 ℃, the mineralization rate of organic phosphorus was calculated after 0.5 h of reaction, and the removal rate of phosphate in water was calculated after 24 h of reaction.

[0031] Example 3

[0032] Take 5.0 g of β-lactoglobulin powder dissolved in 200 mL of ultrapure water, adjust pH = 5, place in 120°C water bath, magnetic stirring for 2 h, to prepare amyloid fibril suspension; under nitrogen protection, 50 mL of 0.1M Cu(II) solution and 50 mL of 2.0M potassium borohydride solution were added dropwise into the above suspension at a rate of 1 mL / min, fully stirred for 2 h, the obtained material was repeatedly washed with ultrapure water to remove impurities, and then vacuum freeze-dried to obtain nZVCu@AF composite material.

[0033] The prepared nZVCu@AF composite material was used for deep treatment of simulated organic phosphorus contaminated wastewater, and the steps were as follows: 50 mL conical flask was used as reactor, THPS solution was used as simulated wastewater, 50 mL of organic phosphorus wastewater, 0.005 g of nZVCu@AF and 0.025 mL of 30% H2O2 were added into the reactor, the reactor was placed in a table constant temperature oscillation incubator for reaction, the rotation speed was 200 rpm, the temperature was 25°C, the mineralization rate of organic phosphorus was calculated after 0.5 h of reaction, and the removal rate of phosphate in water was calculated after 24 h of reaction.

[0034] Example 4

[0035] Take 5.0 g of β-lactoglobulin powder dissolved in 200 mL of ultrapure water, adjust pH = 5, place in 120°C water bath, magnetic stirring for 2 h, to prepare amyloid fibril suspension; under nitrogen protection, 50 mL of 0.1M Cu(II) solution and 50 mL of 2.0M potassium borohydride solution were added dropwise into the above suspension at a rate of 1 mL / min, fully stirred for 2 h, the obtained material was repeatedly washed with ultrapure water to remove impurities, and then vacuum freeze-dried to obtain nZVCu@AF composite material.

[0036] The prepared nZVCu@AF composite material was used for deep treatment of simulated organic phosphorus contaminated wastewater, and the steps were as follows: 50 mL conical flask was used as reactor, THPS solution was used as simulated wastewater, 50 mL of organic phosphorus wastewater, 0.005 g of nZVCu@AF and 0.025 mL of 30% H2O2 were added into the reactor, the reactor was placed in a table constant temperature oscillation incubator for reaction, the rotation speed was 200 rpm, the temperature was 25°C, the mineralization rate of organic phosphorus was calculated after 0.5 h of reaction, and the removal rate of phosphate in water was calculated after 24 h of reaction.

[0037] Example 5

[0038] Take 3.0 g of β-lactoglobulin powder dissolved in 200 mL of ultrapure water, adjust pH = 2, place in a 90°C water bath, magnetic stirring for 5h, prepared into amyloid fibril suspension; under the protection of nitrogen, 50 mL of 0.035M Cu(II) solution and 50 mL of 0.7M potassium borohydride solution were added to the above suspension at a drop rate of 2 mL / min, fully stirred for 2h, the obtained material was washed repeatedly with ultrapure water to remove impurities and vacuum freeze-dried to obtain nZVCu@AF composite material.

[0039] The prepared nZVCu@AF composite material was used for the advanced treatment of simulated organic phosphorus contaminated wastewater, the steps were as follows: 50 mL conical flask was used as the reactor, the simulated wastewater was TCEP solution, 50 mL of organic phosphorus wastewater, 0.008 g of nZVCu@AF and 0.032 mL of 30% H2O2 were added to the reactor, the reactor was placed in a table constant temperature oscillation incubator for reaction, the rotation speed was 200 rpm, the temperature was 25°C, the mineralization rate of organic phosphorus was calculated after 0.5h of reaction, and the removal rate of phosphate in water was calculated after 24h of reaction.

[0040] Example 6

[0041] Take 3.0 g of β-lactoglobulin powder dissolved in 200 mL of ultrapure water, adjust pH = 2, place in a 90°C water bath, magnetic stirring for 5h, prepared into amyloid fibril suspension; under the protection of nitrogen, 50 mL of 0.035M Cu(II) solution and 50 mL of 0.7M potassium borohydride solution were added to the above suspension at a drop rate of 2 mL / min, fully stirred for 2h, the obtained material was washed repeatedly with ultrapure water to remove impurities and vacuum freeze-dried to obtain nZVCu@AF composite material.

[0042] The prepared nZVCu@AF composite material was used for the advanced treatment of simulated organic phosphorus contaminated wastewater, the steps were as follows: 50 mL conical flask was used as the reactor, the simulated wastewater was TCEP solution, 50 mL of organic phosphorus wastewater, 0.008 g of nZVCu@AF and 0.032 mL of 30% H2O2 were added to the reactor, the reactor was placed in a table constant temperature oscillation incubator for reaction, the rotation speed was 200 rpm, the temperature was 25°C, the mineralization rate of organic phosphorus was calculated after 0.5h of reaction, and the removal rate of phosphate in water was calculated after 24h of reaction.

[0043] The nZVCu@AF composite material obtained in any of the above examples was characterized by transmission electron microscopy, and the results were as follows: Figure 1As shown in (a) and (b), the amyloid fibers in nZVCu@AF are about 2-4 μm long and about 5 nm in diameter, and the nZVCu particles with a particle size of about 3-5 nm are uniformly grown on the amyloid fibers. Meanwhile, the nZVCu@AF material is subjected to X-ray diffraction (XRD) analysis, and the results are shown in Figure 2 As shown in (a) and (b), the amyloid fibers in nZVCu@AF are about 2-4 μm long and about 5 nm in diameter, and the nZVCu particles with a particle size of about 3-5 nm are uniformly grown on the amyloid fibers. Meanwhile, the nZVCu@AF material is subjected to X-ray diffraction (XRD) analysis, and the results are shown in 0 As shown in (a) and (b), the amyloid fibers in nZVCu@AF are about 2-4 μm long and about 5 nm in diameter, and the nZVCu particles with a particle size of about 3-5 nm are uniformly grown on the amyloid fibers. Meanwhile, the nZVCu@AF material is subjected to X-ray diffraction (XRD) analysis, and the results are shown in

[0044] The nZVCu@AF composite material prepared in any of the above embodiments is used for deep treatment of simulated organic phosphorus contaminated wastewater, and the application method of the above embodiments is used, wherein the organic phosphorus contaminant is HEDP at a concentration of 20 mg / L, and the pH is 7.0, 8.0, 9.0 and 10.0, respectively. The mineralization rate of organic phosphorus after 0.5 h of reaction and the removal rate of phosphate in water after 24 h of reaction are shown in Table 1.

[0045] Table 1 Deep purification of HEDP in water by nZVCu@AF composite material at different pH

[0046]

[0047] It can be seen that the nZVCu@AF composite material has excellent catalytic performance, shows excellent mineralization capacity for HEDP, and also shows strong adsorption performance for inorganic phosphate produced in the reaction process, and the maximum adsorption capacity can reach 29.8 mg / g.

[0048] The nZVCu@AF composite material prepared in any of the above embodiments is used for deep treatment of simulated organic phosphorus contaminated wastewater, and the application method of the above embodiments is used, wherein the organic phosphorus contaminant is HEDP, and the concentration is 15, 20, 30 and 50 mg / L, respectively. The mineralization rate of organic phosphorus after 0.5 h of reaction and the removal rate of phosphate in water after 24 h of reaction are shown in Table 2.

[0049] Table 2 Deep purification of HEDP in water by nZVCu@AF composite material at different contaminant concentrations

[0050]

[0051] Therefore, the nZVCu@AF composite material has excellent catalytic performance, and the increase of the pollutant concentration has little effect on the mineralization rate of HEDP, and the mineralized phosphate is basically all recovered by in-situ adsorption of the nZVCu@AF composite material, and the adsorption capacity is 4.6-11.9 mg / g.

[0052] The nZVCu@AF composite material prepared in any of the above embodiments is used for deep treatment of simulated organic phosphorus contaminated wastewater, and the application method of the above embodiments is used, wherein the organic phosphorus pollutant is 20 mg / L of THPS, under different pH conditions, the pH is 7.0, 8.0, 9.0 and 10.0 respectively, and the mineralization rate of organic phosphorus after 0.5 h of reaction and the removal rate of phosphate in water after 24 h of reaction are shown in Table 3.

[0053] Table 3 nZVCu@AF composite material for deep purification of THPS in water under different pH conditions

[0054]

[0055] Therefore, the nZVCu@AF composite material has excellent catalytic performance, and the increase of the pollutant concentration has little effect on the mineralization rate of HEDP, and the mineralized phosphate is basically all recovered by in-situ adsorption of the nZVCu@AF composite material, and the adsorption capacity is 4.6-11.9 mg / g.

[0056] The nZVCu@AF composite material prepared in any of the above embodiments is used for deep treatment of simulated organic phosphorus contaminated wastewater, and the application method of the above embodiments is used, wherein the organic phosphorus pollutant is THPS, and the concentration is 5, 10, 20 and 30 mg / L respectively, under the condition of different pH 9.0, the mineralization rate of organic phosphorus after 0.5 h of reaction and the removal rate of phosphate in water after 24 h of reaction are shown in Table 4.

[0057] Table 4 nZVCu@AF composite material for deep purification of THPS in water under different pollutant concentration conditions

[0058]

[0059] Therefore, the nZVCu@AF composite material has excellent catalytic performance, and the increase of the pollutant concentration has little effect on the mineralization rate of HEDP, and the mineralized phosphate is basically all recovered by in-situ adsorption of the nZVCu@AF composite material, and the adsorption capacity is 4.6-11.9 mg / g.

[0060] The nZVCu@AF composite material prepared in any of the above embodiments is used for deep treatment of simulated organic phosphorus contaminated wastewater, and the application method of the above embodiments is used, wherein the organic phosphorus pollutant is 50 mg / L of TCEP, under different pH conditions, the pH is 3.0, 5.0, 7.0 and 8.0 respectively, and the mineralization rate of organic phosphorus after 0.5 h of reaction and the removal rate of phosphate in water after 24 h of reaction are shown in Table 5.

[0061] Table 5 nZVCu@AF composite material for deep purification of TCEP in water under different pH conditions

[0062]

[0063] Therefore, it can be seen that the pH application range of nZVCu@AF is wide, and good catalytic performance is shown under acidic and alkaline conditions, and the mineralization ability of THPS is less affected by pH changes in the range of pH 3.0-8.0. At the same time, inorganic phosphate produced in the reaction process is basically recovered in situ by adsorption, and the adsorption capacity can reach 30.7 mg / g at most.

[0064] The nZVCu@AF composite material prepared in any of the above embodiments is used for deep treatment of simulated organic phosphorus contaminated wastewater, and the application method of the above embodiments is used, wherein the organic phosphorus pollutant is TCEP, and the concentration is 20, 30, 50 and 100 mg / L respectively, under different pH conditions of 7.0, the mineralization rate of organic phosphorus after 0.5 h of reaction and the removal rate of phosphate in water after 24 h of reaction are shown in Table 6.

[0065] Table 6 nZVCu@AF composite material for deep purification of TCEP in water under different pollutant concentration conditions

[0066]

[0067] Therefore, it can be seen that the nZVCu@AF composite material has excellent catalytic performance, and the increase of pollutant concentration has little effect on the mineralization rate of HEDP, and the phosphate after mineralization is basically all recovered in situ by adsorption of the nZVCu@AF composite material, and the adsorption capacity can be up to 21.6 mg / g at most.

[0068] In summary, the method described in the present application can efficiently mineralize various water body refractory organic phosphorus pollutants, including hydroxyethylidene diphosphonic acid HEDP (90%-99%), tetrahydroxy methyl sulfate phosphorus THPS (84%-93%) and tris (2-carboxyethyl) phosphine TCEP (80%-91%), and at the same time, in situ adsorption and recovery of inorganic phosphate is realized, and the adsorption capacity is 3.9-37.3 mg / g.

[0069] The nano zero-valent metal modified amyloid fiber (nZVMs@AF) of the application is used as a catalytic-adsorption material for treating organic phosphorus pollutants in industrial wastewater, which is different from the existing organic phosphorus treatment process that often needs to be combined with advanced oxidation process and chemical precipitation or adsorption process, and through at least two-stage water treatment process combination, the deep treatment of organic phosphorus pollution in industrial wastewater can be realized.nZVMs@AF can simultaneously couple the advanced oxidation process and the adsorption process, highly mineralize the organic phosphorus in the water, in-situ adsorb and recover the inorganic phosphorus product in the wastewater, realize the "one-step" treatment of the phosphorus-containing wastewater, and is a water organic phosphorus treatment strategy with great innovation and development and application potential.

Claims

1. Application of nZVCu@AF composite material in deep treatment of organophosphorus wastewater, characterized by: The preparation method of the nZVCu@AF composite material comprises the following steps: Under nitrogen protection, equal volumes of 0.01-0.1M Cu(II) solution and 0.2-2.0M potassium borohydride solution were added dropwise to the amyloid fiber suspension at the same time. The volume ratio of the dropwise added solution to the amyloid fiber suspension was 1:

2. The reaction was stirred thoroughly for 2-6 hours. The obtained material was repeatedly washed with ultrapure water to remove impurities and then freeze-dried in vacuum to obtain the nZVCu@AF composite material.

2. The use according to claim 1, characterized in that: The application method is as follows: the nZVCu@AF composite material is oscillated with hydrogen peroxide and organophosphorus wastewater at room temperature, and nZVCu@AF, H2O2 and organophosphorus wastewater are mixed in a mass ratio of 1:5:1000~10000. The reaction time is 2-12 hours, so that the hydroxyethylidene diphosphonic acid, tetrahydroxymethylphosphonium sulfate or tris(2-carboxyethyl)phosphine in the organophosphorus wastewater undergoes a mineralization-adsorption reaction, thereby removing the hydroxyethylidene diphosphonic acid, tetrahydroxymethylphosphonium sulfate or tris(2-carboxyethyl)phosphine in the wastewater.

3. The use according to claim 2, characterized in that: Before adding the nZVCu@AF composite material and hydrogen peroxide into the organophosphorus wastewater, the pH of the organophosphorus wastewater was adjusted to 3.0~10.

0.

4. The use according to claim 3, characterized in that: Before adding the nZVCu@AF composite material and hydrogen peroxide into the organophosphorus wastewater, the pH of the organophosphorus wastewater was adjusted to 7.0~8.0.

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