Novel MOFs (Fe-PDA) material as well as preparation method and application thereof

Abstract

The invention provides a novel MOFs (Fe-PDA) material as well as a preparation method and application thereof, and belongs to the technical field of advanced oxidation in wastewater treatment. Comprising the following components in parts by weight: 40 to 50 parts of FeCl3. 6H2O and 40 to 50 parts of pyridine-2, 3-dicarboxylic acid; the preparation steps are as follows. The preparation method comprises the following steps: S1, weighing 40-50 parts of FeCl3. 6H2O, adding the FeCl3. 6H2O into deionized water, and stirring and dissolving the FeCl3. 6H2O; s2, weighing 40-50 parts of pyridine-2, 3-dicarboxylic acid, adding the pyridine-2, 3-dicarboxylic acid into the solution, and stirring for 1 hour; s3, transferring the solution obtained in S2 into a high-pressure reaction kettle, setting the temperature of the high-pressure reaction kettle to be 65 DEG C, and performing hydrothermal treatment at 65 DEG C for 12 hours to obtain a catalyst; s4, finally, the catalyst obtained in S3 is subjected to water washing, alcohol washing, drying and grinding, and the novel MOFs material, namely Fe-PDA, is obtained and applied to efficient degradation of pollutants. The novel MOFs material is designed and synthesized, the valence cycle speed of metal ions is increased, efficient activation of PMS is achieved, and efficient degradation of high-concentration AR18 is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of advanced oxidation in wastewater treatment, and in particular to a novel MOFs (Fe-PDA) material, a preparation method and an application thereof. Background Art

[0002] Advanced oxidation technologies have attracted widespread attention due to their ability to generate a variety of reactive species and possess high mineralization capabilities, enabling the mineralization of pollutants into water, carbon dioxide, and other intermediates. Among these, sulfate-based advanced oxidation technologies have attracted considerable attention due to their ability to generate sulfate radicals. Compared to hydroxyl radicals, sulfate radicals are favored due to their longer half-life, stronger product selectivity, wider pH response range (2-9), and higher electrode potential (2.5-3.1V). Sulfate radicals are generally generated by activating PMS (permonosulfate) and PDS (peroxydisulfate). PMS can be activated to generate reactive radicals through UV activation, thermal activation, alkali activation, transition metal activation, and other methods. Transition metal activation has attracted widespread attention due to its high efficiency in activating PMS.

[0003] However, in the process of activating PMS by transition metals, there is a problem of slow metal valence cycle, which seriously limits the efficient activation rate of PMS. In order to solve this problem, a lot of work has been done to solve this problem. Photocatalytic assistance, reducing co-catalyst MoS2, bimetallic and other methods are used to accelerate the metal valence cycle rate and improve the activation efficiency of PMS. However, the study of accelerating the valence cycle rate of metal ions by suitable ligands found that the valence cycle rate of metal ions is too slow for PMS and has low effect on pollutant cleaning. Therefore, a new MOFs (Fe-PDA) material, preparation method and application are proposed to solve this problem. Summary of the Invention

[0004] In order to make up for the above deficiencies, the present invention provides a new MOFs (Fe-PDA) material, a preparation method and an application thereof, which overcome the above technical problems or at least partially solve the above problems.

[0005] The present invention is achieved in that:

[0006] The invention provides a novel MOFs (Fe-PDA) material. The raw materials thereof are as follows in parts by weight: 40-50 parts of FeCl3·6H2O and 40-50 parts of pyridine-2,3-dicarboxylic acid.

[0007] A method for preparing a novel MOFs (Fe-PDA) material comprises the following steps:

[0008] S1. Weigh 40-50 parts of FeCl3·6H2O and add it to deionized water, stirring to dissolve it;

[0009] S2. Then, 40-50 parts of pyridine-2,3-dicarboxylic acid were weighed and added to the above solution, and stirred for 1 hour;

[0010] S3, transferring the solution obtained in S2 into a high-pressure reactor, setting the temperature of the high-pressure reactor to 65° C., and hydroheating at 65° C. for 12 h to obtain a catalyst;

[0011] S4. Finally, the catalyst obtained in S3 is washed with water, washed with alcohol, dried and ground to obtain a new MOFs material, namely Fe-PDA.

[0012] In a preferred embodiment, after the hydrothermal treatment in S3 is completed, the catalyst is centrifuged, washed three times with deionized water and three times with ethanol, and dried at 60° C. overnight.

[0013] The application of a new MOFs (Fe-PDA) material includes the following steps:

[0014] S1, adding Fe-PDA to AR18 simulated dye wastewater of preset concentration to obtain mixed solution A;

[0015] S2. After stirring the mixed solution A for a certain period of time, PMS was added, the light source was turned on, and the concentration of the solution was monitored using a UV-visible spectrophotometer;

[0016] S3. Establish different environments for removing AR18 simulated wastewater, remove AR18 simulated wastewater under different pH conditions and remove AR18 simulated wastewater under the coexistence of different anions.

[0017] In a preferred embodiment, the pollutants include AR18, BR46, SY, MB and RhB.

[0018] In a preferred embodiment, the distance between the UV-visible spectrophotometer in S2 and the solution is set to 506 nm.

[0019] In a preferred embodiment, the stirring time in S2 is set to 30 minutes to establish adsorption equilibrium.

[0020] In a preferred embodiment, after the step S4 is completed, the catalyst is collected by centrifugation, washed with water and ethanol, and dried at 60° C. overnight.

[0021] The present invention provides a novel MOFs (Fe-PDA) material, preparation method and application, which have the following beneficial effects:

[0022] In this case, a new type of MOFs material - Fe-PDA was designed and synthesized. The catalyst can achieve efficient catalysis of PMS and efficient degradation of high-concentration pollutants (AR18, BR46, SY, MB, RhB). The ligand pyridine-2,3-dicarboxylic acid used in the preparation of the material can accelerate the metal ion valence state cycle rate, solving the problem of slow metal ion valence state cycle rate when transition metal ions activate PMS, and improving the removal effect of pollutants. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 Schematic diagram of the degradation of AR18 in different systems in the present invention;

[0025] Figure 2 Schematic diagram of AR18 degradation under different catalyst concentrations in the present invention;

[0026] Figure 3 Schematic diagram of AR18 degradation under different PMS concentrations in the present invention;

[0027] Figure 4 Schematic diagram of AR18 degradation at different pH values in the present invention;

[0028] Figure 5 The present invention is to degrade AR18 in the presence of coexisting anions and humic acid.

[0029] Figure 6 This is the quenching experiment of the Fe-PDA / PMS / Vis system in the present invention;

[0030] Figure 7 Schematic diagram of the degradation of BR46, SY, MB and RhB by Fe-PDA under dark conditions in the present invention;

[0031] Figure 8 Schematic diagram of the cyclic experiment of AR18 degradation by Fe-PDA in the present invention. DETAILED DESCRIPTION

[0032] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0033] Reference Figure 1-8 The present invention provides a technical solution: a new MOFs (Fe-PDA) material, the raw materials of which are as follows by weight: 40-50 parts of FeCl3·6H2O and 40-50 parts of pyridine-2,3-dicarboxylic acid.

[0034] A method for preparing a novel MOFs (Fe-PDA) material comprises the following steps:

[0035] S1. Weigh 40-50 parts of FeCl3·6H2O and add it to deionized water, stirring to dissolve it;

[0036] S2. Then, 40-50 parts of pyridine-2,3-dicarboxylic acid were weighed and added to the above solution, and stirred for 1 hour;

[0037] S3, transferring the solution obtained in S2 into a high-pressure reactor, setting the temperature of the high-pressure reactor to 65° C., and hydroheating at 65° C. for 12 h to obtain a catalyst;

[0038] S4. Finally, the catalyst obtained in S3 is washed with water, washed with alcohol, dried and ground to obtain a new MOFs material, namely Fe-PDA.

[0039] After the hydrothermal treatment in S3 is completed, the catalyst is centrifuged and washed three times with deionized water and ethanol, and dried at 60°C overnight. The catalyst Fe-PDA is a new catalyst formed by coordination of FeCl3 and pyridine-2,3-dicarboxylic acid. In the synthesis of the catalyst Fe-PDA, the molar ratio of FeCl3 and pyridine-2,3-dicarboxylic acid is 1:1.

[0040] The application of a new MOFs (Fe-PDA) material includes the following steps:

[0041] S1, adding Fe-PDA to AR18 simulated dye wastewater of preset concentration to obtain mixed solution A;

[0042] S2. After stirring the mixed solution A for a certain period of time, PMS was added, the light source was turned on, and the concentration of the solution was monitored using a UV-visible spectrophotometer;

[0043] S3. Establish different environments for removing AR18 simulated wastewater, remove AR18 simulated wastewater under different pH conditions and remove AR18 simulated wastewater under the coexistence of different anions.

[0044] The contaminants include AR18, BR46, SY, MB and RhB.

[0045] The distance between the UV-visible spectrophotometer and the solution in S2 is set to 506 nm.

[0046] The stirring time in S2 is set to 30 min to establish adsorption equilibrium.

[0047] After the step S4 is completed, the catalyst is collected by centrifugation, washed with water and ethanol, and dried at 60° C. overnight.

[0048] Calculation of degradation rate and pollutant removal amount: μ represents the removal rate of pollutants, C t represents the concentration of pollutants at any time during the reaction, C0 represents the initial concentration of pollutants, R (removal amount) represents the amount of pollutants removed, V represents the volume of the solution, M r represents the relative molecular weight of the pollutant, and m represents the mass of the catalyst added to the reaction system. After dimensionless processing, the pollutant removal amount R is obtained by the following formula:

[0049]

[0050] Example 1

[0051] 25mL AR18 (1000mg / L) was measured, and degradation experiments on AR18 by PMS and Fe-PDA / PMS systems were carried out under light and dark conditions, respectively. The concentration of AR18 was monitored at 506nm using a UV-visible spectrophotometer. It was calculated that Fe-PDA showed excellent degradation performance on AR18 under both light and dark conditions.

[0052] Example 2

[0053] The effect of catalyst concentration on AR18 degradation in the reaction system was investigated. 25 mL of AR18 (1000 mg / L) was added to various catalyst concentrations (0.4-1.2 g / L) and stirred for 30 minutes to establish adsorption equilibrium. PMS (3 mM) was then added, and the light source was turned on to conduct AR18 degradation experiments. AR18 concentration was monitored using a UV-visible spectrophotometer at 506 nm. Calculations showed that Fe-PDA had optimal AR18 degradation efficiency at catalyst concentrations between 1 g / L and 1.2 g / L.

[0054] Example 3

[0055] The effect of PMS concentration on AR18 degradation in the reaction system was investigated. 25 mL of AR18 (1000 mg / L) was added to 25 mg of the catalyst and stirred for 30 minutes to establish adsorption equilibrium. Subsequently, varying amounts of PMS (0.5-5 mM) were added, and AR18 degradation experiments were performed under a light source. AR18 concentration was monitored using a UV-visible spectrophotometer at 506 nm. Calculations showed that Fe-PDA exhibited optimal AR18 degradation efficiency when the PMS (permonosulfate) concentration was between 3 mM and 5 mM.

[0056] Example 4

[0057] The effect of pH on AR18 degradation in the reaction system was investigated. The pH of AR18 was adjusted using 1M HCl and 1M NaOH, followed by the addition of 25mg of the catalyst and stirring for 30 minutes to establish adsorption equilibrium. Subsequently, varying amounts of PMS (3mM) were added, and AR18 degradation experiments were performed using a light source. AR18 concentration was monitored using a UV-visible spectrophotometer at 506nm. Calculations indicate that Fe-PDA exhibits optimal AR18 degradation efficiency when the solution pH is >7.

[0058] Example 5

[0059] The effects of coexisting anions and humic acid on the degradation of AR18 were investigated. A certain amount of anionic salt solution was added to the AR18 solution, and the corresponding coexisting anion and humic acid solution were prepared. 25 mL of AR18 was measured, 25 mg of catalyst was added, and stirred for 30 minutes to establish adsorption equilibrium. PMS (3 mM) was then added, and the light source was turned on to conduct AR18 degradation experiments. The concentration of AR18 was monitored at 506 nm using a UV-visible spectrophotometer. Calculations showed that when there was no H2PO4- in the solution, the degradation of AR18 by Fe-PDA was basically unaffected in the presence of multiple coexisting anions and humic acid.

[0060] Example 6

[0061] Degradation experiments were conducted on other high-concentration pollutants (BR46, SY, MB, and RhB = 500 mg / L) in the reaction system. 25 mL of AR18 was added to 25 mg of the catalyst and stirred for 30 minutes to establish adsorption equilibrium. PMS (3 mM) was then added, and the light source was turned on for AR18 degradation. Contaminant concentrations were monitored using a UV-visible spectrophotometer at 531 nm, 482 nm, 663 nm, and 554 nm. Calculations showed that the Fe-PDA catalyst had high degradation performance against multiple pollutants (BR46, SY, MB, and RhB).

[0062] Example 7

[0063] The catalyst's cyclic performance was evaluated. After each AR18 degradation experiment, the catalyst was collected by centrifugation, washed with water and ethanol, and dried overnight at 60°C. 25 mL of AR18 was added to 25 mg of the catalyst and stirred for 30 minutes to establish adsorption equilibrium. PMS (3 mM) was then added, and the light source was turned on for AR18 degradation experiments. AR18 concentration was monitored at 506 nm using a UV-visible spectrophotometer. Multiple calculations revealed that Fe-PDA had optimal AR18 degradation efficiency at catalyst concentrations between 1 g / L and 1.2 g / L.

[0064] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made in accordance with the spirit of the present invention are intended to be covered by the scope of protection of the present invention.

Claims

1. A new type of MOFs (Fe-PDA) material, characterized in that: The raw materials are as follows by weight: 40-50 parts of FeCl3·6H2O and 40-50 parts of pyridine-2,3-dicarboxylic acid.

2. A method for preparing a novel MOFs (Fe-PDA) material, for preparing the novel MOFs (Fe-PDA) material according to claim 1, characterized in that: The steps include: S1. Weigh 40-50 parts of FeCl3·6H2O and add it to deionized water, stirring to dissolve it; S2. Then, 40-50 parts of pyridine-2,3-dicarboxylic acid were weighed and added to the above solution, and stirred for 1 hour; S3, transferring the solution obtained in S2 into a high-pressure reactor, setting the temperature of the high-pressure reactor to 65° C., and hydroheating at 65° C. for 12 h to obtain a catalyst; S4. Finally, the catalyst obtained in S3 is washed with water, washed with alcohol, dried and ground to obtain a new MOFs material, namely Fe-PDA.

3. The method for preparing a novel MOFs (Fe-PDA) material according to claim 2, characterized in that: After the hydrothermal treatment in S3 is completed, the catalyst is centrifuged, washed three times with deionized water and three times with ethanol, and dried at 60° C. overnight.

4. Application of a novel MOFs (Fe-PDA) material, wherein the MOFs (Fe-PDA) material prepared according to claim 2 is applied to the efficient degradation of pollutants, characterized in that: The steps include: S1, adding Fe-PDA to AR18 simulated dye wastewater of preset concentration to obtain mixed solution A; S2. After stirring the mixed solution A for a certain period of time, PMS was added, the light source was turned on, and the concentration of the solution was monitored using a UV-visible spectrophotometer; S3. Establish different environments for removing AR18 simulated wastewater, remove AR18 simulated wastewater under different pH conditions and remove AR18 simulated wastewater under the coexistence of different anions.

5. The use of a novel MOFs (Fe-PDA) material according to claim 4, characterized in that: The contaminants include AR18, BR46, SY, MB and RhB.

6. The use of a novel MOFs (Fe-PDA) material according to claim 5, characterized in that: The distance between the UV-visible spectrophotometer and the solution in S2 is set to 506nm-554nm.

7. The use of a novel MOFs (Fe-PDA) material according to claim 6, characterized in that: The stirring time in S2 is set to 30 min to establish adsorption equilibrium.

8. The use of a novel MOFs (Fe-PDA) material according to claim 7, characterized in that: After the step S4 is completed, the catalyst is collected by centrifugation, washed with water and ethanol, and dried at 60° C. overnight.

Images