Beta-phase iron molybdate (II) catalyst as well as preparation method and application thereof

Abstract

The invention relates to a beta-phase iron molybdate (II) catalyst as well as a preparation method and application thereof. The preparation method of the beta-phase iron molybdate (II) catalyst comprises the following steps: dissolving 5-8 mmol of a molybdenum source in 15-24 mL of water to obtain a solution I, dissolving 5-8 mmol of an iron source in 15-24 mL of water to obtain a solution II, adding the solution II into the solution I to obtain a reaction mixed solution, fully stirring the reaction mixed solution, then carrying out a hydrothermal reaction, cooling after the reaction is finished, and filtering to obtain the beta-phase iron molybdate (II) catalyst. And washing to obtain a precipitate, and drying the precipitate to obtain the product. The beta-phase iron molybdate (II) is efficiently and rapidly prepared by adopting a hydrothermal method, compared with a solvothermal method, the risk of raw materials is high, the reaction conditions of the hydrothermal method are relatively mild, and certain technical support is provided for efficient, simple and convenient synthesis of the beta-phase iron molybdate (II).

Description

Technical Field

[0001] The invention belongs to the technical field of catalysts, and specifically relates to a beta-phase iron (II) molybdate catalyst, a preparation method and an application thereof. Background Art

[0002] Iron molybdate (II) is a good catalyst with catalytic, optical and magnetic properties. Its application prospects in photoluminescence, microwave transmission, optical fiber, magnetic materials, humidity sensors and catalysis have attracted wide attention. In recent years, it has also been used as an alloying raw material in the metallurgical field to produce molybdenum-containing alloy steel. The existing preparation methods of iron molybdate (II) mainly include hydrothermal method and microwave radiation method. The hydrothermal method requires high temperature and high pressure environment to prepare iron molybdate (II). The process is simple, but the preparation efficiency needs to be improved. The microwave method has high requirements for equipment, and the prepared materials are all iron molybdate (II) nanomaterials.

[0003] The invention patent with application publication number CN103754954A discloses a method for preparing iron (II) molybdate nanocubes, which comprises the following steps: (1) adding an iron source and a molybdenum source in a molar ratio (1.5-3):1 to a mixture of sodium acetate and polyvinyl pyrrolidone in an alcohol-water solution with a mass percentage concentration of 0.3-2.0% and stirring and mixing evenly; (2) transferring the mixture obtained in step (1) to a closed reactor at 100-250°C, reacting for 8-40 hours, naturally cooling to room temperature, and separating and purifying to obtain the target product. The method for preparing iron (II) molybdate nanocubes obtains a mixture of two forms, α-phase iron (II) molybdate and β-phase iron (II) molybdate, and cannot prepare a single β-phase iron (II) molybdate. Summary of the invention

[0004] The first object of the present invention is to provide a method for preparing a β-phase iron (II) molybdate catalyst to solve the technical problem that a single β-phase iron (II) molybdate cannot be obtained by a hydrothermal method in the prior art.

[0005] The second object of the present invention is to provide a β-phase iron (II) molybdate catalyst.

[0006] The third object of the present invention is to provide an application of a β-phase iron (II) molybdate catalyst.

[0007] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0008] A preparation method of a β-phase iron (II) molybdate catalyst comprises the following steps: dissolving 5-8 mmol of a molybdenum source in 15-24 mL of water to obtain a first solution, dissolving 5-8 mmol of an iron source in 15-24 mL of water to obtain a second solution, adding the second solution into the first solution to obtain a reaction mixture, fully stirring the reaction mixture and then performing a hydrothermal reaction, cooling after the reaction is completed, washing to obtain a precipitate, and drying the precipitate to obtain the catalyst.

[0009] Furthermore, the temperature of the hydrothermal reaction is 180° C., and the time of the hydrothermal reaction is 12 h.

[0010] Furthermore, the molybdenum source is a hexavalent molybdenum salt, and the iron salt is a ferrous salt.

[0011] Furthermore, the molybdenum source is sodium molybdate dihydrate, and the iron salt is ferrous sulfate heptahydrate.

[0012] Furthermore, the hydrothermal reaction is carried out in an electric constant temperature blast drying oven, and the power consumption of the electric constant temperature blast drying oven is ≤950W.

[0013] Furthermore, the washing method is to wash with water in a circulating manner for 3 to 5 times.

[0014] Furthermore, the drying method is to dry in a vacuum drying oven at a temperature of 60 to 80° C. for 12 to 24 hours, and the power consumption of the vacuum drying oven is less than 350W.

[0015] Furthermore, the stirring time is 10 to 20 minutes.

[0016] A beta-phase iron (II) molybdate catalyst is prepared by adopting the preparation method of the beta-phase iron (II) molybdate catalyst.

[0017] A β-phase iron (II) molybdate catalyst is used as a catalyst for activating persulfate in the catalytic degradation of bisphenol AF in water.

[0018] Beneficial effects of the present invention:

[0019] The present invention adopts a hydrothermal method to efficiently and quickly prepare a β-phase iron (II) molybdate. Compared with the solvent thermal method in which the raw materials are highly dangerous, the reaction conditions of the hydrothermal method of the present invention are relatively mild, which provides certain technical support for the efficient and simple synthesis of β-phase iron (II) molybdate.

[0020] The β-phase iron (II) molybdate catalyst of the present invention exhibits efficient catalytic performance and excellent stability in the degradation of bisphenol AF in water. The β-phase iron (II) molybdate catalyst of the present invention is applied to the photocatalytic degradation of bisphenol AF in water. After adding sodium persulfate and irradiating with light for 60 minutes, the removal rate of bisphenol AF is as high as 99.8%. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a product diagram of the β-phase iron (II) molybdate catalyst in Example 1;

[0022] Figure 2 is the XRD pattern of the β-phase iron (II) molybdate catalyst in Example 1;

[0023] Figure 3 This is the SEM image of the β-phase iron (II) molybdate catalyst in Example 1. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the embodiments of the present invention and the accompanying drawings.

[0025] Example 1

[0026] The preparation method of the β-phase iron molybdate (II) catalyst of Example 1 comprises the following steps: dissolving 1.21 g of sodium molybdate dihydrate in 15 mL of deionized water to obtain solution 1, dissolving 1.39 g of ferrous sulfate heptahydrate in 15 mL of deionized water to obtain solution 2, adding solution 2 to solution 1 to obtain a reaction mixture, stirring the reaction mixture for 10 min and then transferring it to a hydrothermal reactor, and performing a hydrothermal reaction in an electric constant temperature blast drying oven with a power consumption of 950 W, cooling after the reaction is completed, and washing the cooled reaction mixture with deionized water for 3 times to obtain a precipitate, drying the precipitate in a vacuum drying oven, and grinding to obtain a β-phase iron molybdate (II) catalyst, from Figure 3 It can be seen that the β-phase iron (II) molybdate catalyst has a cubic structure. The temperature of the hydrothermal reaction is 180°C, and the time of the hydrothermal reaction is 12h. The temperature of the vacuum drying is 60°C, the time of the vacuum drying is 12h, and the power consumption of the vacuum drying oven is 250W.

[0027] Example 2

[0028] The preparation method of the β-phase iron molybdate (II) catalyst of Example 2 comprises the following steps: dissolving 1.936g of sodium molybdate dihydrate in 15mL of deionized water to obtain solution 1, dissolving 2.224g of ferrous sulfate heptahydrate in 15mL of deionized water to obtain solution 2, adding solution 2 to solution 1 to obtain a reaction mixture, stirring the reaction mixture for 15min and transferring it to a hydrothermal reactor, and performing a hydrothermal reaction in an electric constant temperature blast drying oven with a power consumption of 900W, cooling after the reaction is completed, and washing the cooled reaction mixture with deionized water for 4 times to obtain a precipitate, drying the precipitate in a vacuum drying oven, and grinding to obtain a β-phase iron molybdate (II) catalyst. The temperature of the hydrothermal reaction is 180°C, and the time of the hydrothermal reaction is 12h. The temperature of vacuum drying is 60°C, the time of vacuum drying is 20h, and the power consumption of the vacuum drying oven is 300W.

[0029] Example 3

[0030] The preparation method of the β-phase iron molybdate (II) catalyst of Example 3 comprises the following steps: dissolving 1.936g of sodium molybdate dihydrate in 18mL of deionized water to obtain solution 1, dissolving 2.224g of ferrous sulfate heptahydrate in 18mL of deionized water to obtain solution 2, adding solution 2 to solution 1 to obtain a reaction mixture, stirring the reaction mixture for 20min and transferring it to a hydrothermal reactor, and performing a hydrothermal reaction in an electric constant temperature blast drying oven with a power consumption of 850W, cooling after the reaction is completed, and washing the cooled reaction mixture with deionized water for 5 times to obtain a precipitate, drying the precipitate in a vacuum drying oven, and grinding to obtain a β-phase iron molybdate (II) catalyst. The temperature of the hydrothermal reaction is 180°C, and the time of the hydrothermal reaction is 12h. The temperature of vacuum drying is 80°C, the time of vacuum drying is 24h, and the power consumption of the vacuum drying oven is 340W.

[0031] The β-phase iron (II) molybdate catalyst of Example 1 was added to the pretreated water containing bisphenol AF and mixed evenly, and then sodium persulfate was added. After irradiation with visible light for 60 minutes, the removal rate of bisphenol AF in the pretreated water was 99.8%. The concentration of bisphenol AF in the pretreated water was 10 mg / L.

Claims

1. A method for preparing a β-phase iron (II) molybdate catalyst, characterized in that: The method comprises the following steps: dissolving 5 to 8 mmol of a molybdenum source in 15 to 24 mL of water to obtain a solution 1, dissolving 5 to 8 mmol of an iron source in 15 to 24 mL of water to obtain a solution 2, adding the solution 2 to the solution 1 to obtain a reaction mixture, fully stirring the reaction mixture and then performing a hydrothermal reaction, cooling after the reaction is completed, washing to obtain a precipitate, and drying the precipitate to obtain the product.

2. The method for preparing the β-phase iron (II) molybdate catalyst according to claim 1, characterized in that: The temperature of the hydrothermal reaction is 180° C., and the time of the hydrothermal reaction is 12 h.

3. The method for preparing a β-phase iron (II) molybdate catalyst according to claim 1, characterized in that: The molybdenum source is a hexavalent molybdenum salt, and the iron salt is a ferrous salt.

4. The method for preparing the β-phase iron (II) molybdate catalyst according to claim 3, characterized in that: The molybdenum source is sodium molybdate dihydrate, and the iron salt is ferrous sulfate heptahydrate.

5. The method for preparing the β-phase iron (II) molybdate catalyst according to claim 1, characterized in that: The hydrothermal reaction is carried out in an electric constant temperature blast drying oven, and the power consumption of the electric constant temperature blast drying oven is ≤950W.

6. The method for preparing the β-phase iron (II) molybdate catalyst according to claim 1, characterized in that: The washing method is to wash with water in a circulating manner for 3 to 5 times.

7. The method for preparing the β-phase iron (II) molybdate catalyst according to claim 1, characterized in that: The drying method comprises drying in a vacuum drying oven at a temperature of 60 to 80° C. for 12 to 24 hours, and the power consumption of the vacuum drying oven is less than 350W.

8. The method for preparing the β-phase iron (II) molybdate catalyst according to claim 1, characterized in that: The stirring time is 10 to 20 minutes.

9. A β-phase iron (II) molybdate catalyst, characterized in that: The catalyst is prepared by the method for preparing the β-phase iron (II) molybdate catalyst described in any one of claims 1 to 8.

10. Use of the β-phase iron (II) molybdate catalyst as claimed in claim 9 as a catalyst for activating persulfate in the catalytic degradation of bisphenol AF in water.

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