CN114308047B

CN114308047B - Light degradation material for organic wastewater

Info

Publication number: CN114308047B
Application number: CN202210019468.XA
Authority: CN
Inventors: 张庆昌
Original assignee: Puyang Zhonghui New Energy Technology Co ltd
Current assignee: Puyang Zhonghui New Energy Technology Co ltd
Priority date: 2022-01-10
Filing date: 2022-01-10
Publication date: 2022-11-01
Anticipated expiration: 2042-01-10
Also published as: CN114308047A

Abstract

The invention relates to a photodegradation material for organic wastewater, which is characterized by being prepared by the following process: adding a cobalt source and an iron source into a mixed solvent of glycerol and water, then adding tetramethylammonium hydroxide, uniformly mixing by ultrasonic waves, and heating and refluxing for 2-3h at 90-130 ℃ to obtain flower-shaped CoFe₂O₄(ii) a Flower-shaped CoFe₂O₄Dissolving in deionized water, adding bismuth salt, ferric salt, urea and L-cysteine at a certain ratio, stirring, transferring into a high-pressure reaction kettle, and performing hydrothermal reaction to obtain flower-shaped CoFe₂O₄Loaded with nano Bi₂Fe₄O₉The flower-like CoFe₂O₄Greatly increases the specific surface area, and is formed by flower-shaped CoFe₂O₄Loaded with nano Bi₂Fe₄O₉And the heterojunction structure formed by the two can effectively inhibit the recombination of the photo-generated electron hole pair, thereby obviously improving the efficiency of photocatalytic degradation of organic pollutants.

Description

Light degradation material for organic wastewater

Technical Field

The invention relates to the technical field of degradation of organic pollutants in wastewater.

Background

With the rapid development of economy, organic pollutants such as dyes and antibiotics cause harm to drinking water and ecological environment, and seriously threaten the normal life and environment of human beings. The photocatalysis technology is a new pollution treatment technology, has the advantages of high efficiency, energy conservation, high utilization efficiency of visible light, no secondary pollution and the like, is widely concerned by researchers, and has wide application prospect in the technical field of organic pollutant degradation.

CN104525199A discloses ternary Bi₂WO₆-Ag-AgBi(WO₄)₂A nano material and a method for degrading organic matters by visible light catalysis. The photocatalytic degradation of organic matters can be carried out under visible light, and the photocatalytic degradation can be repeatedly utilized. The catalytic degradation effect is prominent under the actual outdoor sunlight condition.

CN108906123A heteropoly acid-functionalized graphene oxide composite catalytic material, a preparation method and application thereof. Firstly, mixing ethylenediamine and graphene oxide, heating and reacting, and performing disordered self-assembly on the graphene oxide under the action of amine to obtain functional graphene oxide with a cross-linked network structure; and then mixing, stirring, ultrasonically treating and drying the heteropoly acid and the functionalized graphite oxide to obtain the graphene oxide-heteropoly acid composite catalytic material. The raw materials are easy to obtain, the preparation method is simple, compared with the traditional heteropoly acid photodegradation reaction which needs an ultraviolet lamp, the catalytic material prepared by the method can be used for removing organic pollutants in water under the condition of sunlight, the catalytic reaction activity is high, and the catalytic material can be recycled.

Disclosure of Invention

The invention aims to provide a composite photocatalyst which is large in specific surface area, multiple in active sites and high in photo-generated electron-hole utilization rate.

The material for photodegradation of organic wastewater is characterized by being prepared by adopting the following process: adding a cobalt source and an iron source into a mixed solvent of glycerol and water, then adding tetramethylammonium hydroxide, uniformly mixing by ultrasonic waves, and heating and refluxing for 2-3h at 90-130 ℃ to obtain flower-shaped CoFe₂O₄(ii) a Flower-shaped CoFe₂O₄Dissolving in deionized water, adding bismuth salt, ferric salt, urea and L-cysteine at a certain ratio, stirring, transferring into a high-pressure reaction kettle, and performing hydrothermal reaction to obtain flower-shaped CoFe₂O₄Loaded with nano Bi₂Fe₄O₉The composite photocatalyst of (1).

Preferably, the cobalt source and the iron source are cobalt nitrate and ferric nitrate;

preferably, the ratio of glycerol to water is 1:1;

preferably, the adding ratio of the cobalt source, the iron source and the tetramethylammonium hydroxide is (5-20) mmol: (10-40) mmol: (10-20) mg;

the bismuth salt and the ferric salt are respectively bismuth nitrate and ferric nitrate;

the reaction ratio of the bismuth salt, the ferric salt, the urea and the L-cysteine is (2-5) mmol: (4-10) mmol: (4-10) mmol: (10-20) mg;

the technical effects are as follows:

the flower-shaped CoFe is prepared by controlling the proportion of glycerol and water and adding tetramethylammonium hydroxide₂O₄(ii) a The three-dimensional flower-shaped structure greatly improves the specific surface area, is beneficial to light refraction and is easy to expose active sites; by flower-like CoFe₂O₄Loaded with nano Bi₂Fe₄O₉Avoid Bi₂Fe₄O₉The problem of agglomeration and the heterojunction structure formed by the two can effectively inhibit the recombination of photo-generated electron hole pairs, thereby remarkably improving the efficiency of photocatalytic degradation of organic pollutants.

Drawings

FIG. 1 shows flower-like CoFe of example 1 of the present application₂O₄Loaded with nano Bi₂Fe₄O₉SEM picture of (1);

Detailed Description

Example 1

Adding 5mmol of cobalt nitrate and 10mmol of ferric nitrate into 80ml of the mixture in a volume ratio of 1:1, adding 15mg of tetramethylammonium hydroxide into a mixed solvent of glycerol and water, uniformly mixing by ultrasonic waves, and heating and refluxing for 3 hours at 100 ℃ to obtain flower-shaped CoFe₂O₄(ii) a Flower-shaped CoFe₂O₄Dissolving in 50ml of deionized water, then adding 2mmol of bismuth nitrate, 4mmol of ferric nitrate, 4mmol of urea and 15mg of L-cysteine, stirring uniformly, transferring into a high-pressure reaction kettle for hydrothermal reaction at 180 ℃ for 10h to obtain flower-shaped CoFe₂O₄Loaded with nano Bi₂Fe₄O₉The composite photocatalyst of (1).

Comparative example 1

Adding 5mmol of cobalt nitrate and 10mmol of ferric nitrate into 80ml of the mixture in a volume ratio of 1:1, adding 15mg of tetramethylammonium hydroxide into a mixed solvent of glycerol and water, uniformly mixing by ultrasonic waves, and heating and refluxing for 3 hours at 100 ℃ to obtain flower-shaped CoFe₂O₄。

Comparative example 2

Adding 2mmol of bismuth nitrate and 4mmol of bismuth nitrate into 50ml of deionized waterL ferric nitrate, 4mmol urea and 15mg L-cysteine, stirring uniformly, transferring into a high-pressure reaction kettle for hydrothermal reaction at 180 ℃ for 10h to obtain Bi₂Fe₄O₉。

Efficiency of methylene blue degradation

Preparing methylene blue wastewater with the concentration of 30ppm, taking 10mL of the methylene blue wastewater into a quartz tube, adding 20mg of the materials of the example 1 and the comparative examples 1-2 for preparation, stirring for 60min, and irradiating under a 300w xenon lamp for 2h. The degradation rate of methylene blue was measured at different time periods.

	Example 1	Comparative example 1	Comparative example 2
				20min	15％	8％	4％
40min	43％	16％	14％
				60min	89％	28％	23％
80min	99％	56％	45％
				100min	99％	77％	71％
120min	99％	82％	85％

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. A composite photocatalyst for organic wastewater photodegradation is characterized by being prepared by adopting the following processes: adding a cobalt source and an iron source into a mixed solvent of glycerol and water, wherein the volume ratio of the glycerol to the water is 1:1, adding tetramethylammonium hydroxide, uniformly mixing by ultrasonic, heating and refluxing for 2-3h at 90-130 ℃ to obtain flower-shaped CoFe₂O₄The adding proportion of the cobalt source, the iron source and the tetramethyl ammonium hydroxide is (5-20) mmol: (10-40) mmol: (10-20) mg; flower-shaped CoFe₂O₄Dissolving in deionized water, and then adding bismuth salt, ferric salt, urea and L-cysteine according to a certain proportion, wherein the reaction proportion of the bismuth salt, the ferric salt, the urea and the L-cysteine is (2-5) mmol: (4-10) mmol: (4-10) mmol: (10-20) mg; after being stirred evenly, the mixture is transferred into a high-pressure reaction kettle for hydrothermal reaction, and water is addedThe thermal reaction temperature is 180-200 ℃, and the reaction time is 10-20h; obtaining flower-shaped CoFe₂O₄Loaded with nano Bi₂Fe₄O₉The composite photocatalyst of (1).

2. The composite photocatalyst for photodegradation of organic wastewater according to claim 1, wherein the cobalt source and the iron source are cobalt nitrate and iron nitrate respectively.

3. The composite photocatalyst for photodegradation of organic wastewater according to claim 1, wherein the bismuth salt and the ferric salt are bismuth nitrate and ferric nitrate respectively.