Synthetic method of magnetic cobalt ferrite Fenton-like catalyst

Abstract

The invention provides a synthetic method of a magnetic cobalt ferrite Fenton-like catalyst. The synthetic method comprises the following specific synthetic operation steps: S1, preparing and treating raw materials of the catalyst; s2, preparing a catalyst solution; s3, catalyst crystal precipitation preparation optimization treatment; s4, adjusting and optimizing the stability of the catalyst; s5, carrying out solid-phase transition operation on the catalyst; s6, carrying out functionalization treatment on the catalyst; and S7, performance testing of the finished product catalyst: raw material preparation, solution preparation, crystal precipitation preparation, stability adjustment, solid phase transformation, functionalization treatment and performance testing are sequentially performed on the raw materials of the catalyst through the seven steps, and the catalyst is synthesized by adopting a coprecipitation method and a template method in the crystal precipitation preparation process. The growth direction and the growth rate of the crystal can be controlled through the action of the template, and a functional group and a coating agent with relatively high stability are introduced into the catalyst, so that the surface of the catalyst is protected.

Description

Technical Field

[0001] The invention relates to the technical field of catalyst synthesis, in particular to a method for synthesizing a magnetic cobalt ferrite Fenton catalyst. Background Art

[0002] Magnetic cobalt ferrite Fenton catalyst is a new type of catalyst that combines the characteristics of magnetic materials and Fenton catalytic reaction. It has the ability to control the generation and decomposition of active oxygen free radicals under visible light, thereby achieving the ability to efficiently degrade organic wastewater. This catalyst is usually composed of magnetic materials such as cobalt iron oxide, and a certain amount of functional groups are implanted and modified on its surface to enhance its adsorption and oxidation ability for organic matter in organic wastewater. Under light, the functional groups on the surface of the catalyst can promote the Fenton reaction, generate active oxygen free radicals, and then degrade organic matter in organic wastewater. Magnetic cobalt ferrite Fenton catalyst has broad application prospects in water treatment, wastewater treatment and other fields.

[0003] However, the existing magnetic cobalt ferrite Fenton catalyst has the following problems during the synthesis process: the magnetic cobalt ferrite Fenton catalyst may have crystal defects, inconsistent grain size, and uneven and incomplete surface modification during the synthesis process, which affects the stability and regeneration of the catalyst. In addition, there may be factors that lead to insufficient catalyst stability during the synthesis process, such as crystal structure defects, active group deactivation, etc. Therefore, it is necessary to design corresponding technical solutions to solve the existing technical problems. Summary of the invention

[0004] The purpose of the present invention is to provide a method for synthesizing a magnetic cobalt ferrite Fenton catalyst, which solves the problem that the magnetic cobalt ferrite Fenton catalyst may have crystal defects, inconsistent grain size, and uneven and incomplete surface modification during the synthesis process, which affects the stability and regeneration of the catalyst. In addition, there may be factors that lead to insufficient catalyst stability during the synthesis process, such as crystal structure defects, inactivation of active groups, etc., which is a technical problem.

[0005] To achieve the above object, the present invention provides the following technical solution: a method for synthesizing a magnetic cobalt ferrite Fenton catalyst, wherein the specific synthesis operation steps are as follows:

[0006] S1: Catalyst raw material preparation and processing;

[0007] S2: catalyst solution preparation operation;

[0008] S3: Catalyst crystal precipitation preparation optimization process;

[0009] S4: catalyst stability adjustment and optimization treatment;

[0010] S5: catalyst solid phase transformation operation;

[0011] S6: Catalyst functionalization treatment;

[0012] S7: Finished catalyst performance test;

[0013] Through the above seven steps, the catalyst raw materials are sequentially subjected to raw material preparation, solution preparation, crystal precipitation preparation, stability adjustment, solid phase transformation, functionalization treatment and performance testing. In the process of crystal precipitation preparation, the co-precipitation method and the template method are used to synthesize the catalyst to control the growth rate and grain size of the crystal, thereby improving the uniformity of the grains. The growth direction and rate of the crystal can be controlled by the effect of the template, thereby obtaining more uniform grains. In addition, in the process of catalyst stability adjustment, functional groups and coating agents with higher stability are introduced to protect the catalyst surface and prevent it from being damaged or inactivated during the reaction.

[0014] As a preferred embodiment of the present invention, S1: catalyst raw material preparation and treatment, including cobalt salt, iron salt, carrier material, surfactant and auxiliary agent, wherein the mass ratio of cobalt salt to iron salt is 3:1, the cobalt salt is cobalt chloride, the iron salt is ferric chloride, the carrier material is one of silicon dioxide and aluminum oxide, and the auxiliary agent includes a reducing agent, a stabilizer, and an activator.

[0015] As a preferred embodiment of the present invention, S2: dissolving the metal salt of the catalyst raw material prepared in step 1 in a mixing container to form a metal ion solution, and introducing a carrier material, a surfactant and an auxiliary agent into the solution to obtain a catalyst mixture.

[0016] As a preferred embodiment of the present invention, S3: adding a precipitant and an alkaline solution to the catalyst mixture prepared in step 2 by a coprecipitation method to precipitate cobalt iron hydroxide in the solution, synthesizing the catalyst by a template method, and controlling the growth direction and rate of the crystal by the effect of the template.

[0017] As a preferred embodiment of the present invention, S4: during the crystal formation process in step 3, stable functional groups and capping agents are introduced to protect the catalyst surface, wherein the functional groups are selected from carboxyl and hydroxyl groups and the ratio of the two is 1:1.

[0018] As a preferred embodiment of the present invention, S5: the crystalline material obtained above is precipitated and fixed on a carrier and introduced into a calcination container for calcination treatment, the calcination temperature of the magnetic cobalt ferrite Fenton catalyst is controlled at 400°C to 800°C, the calcination time is controlled at 1 hour to 4 hours, and nitrogen is introduced during the calcination process to protect the catalyst from oxidation. After the calcination, the catalyst is slowly cooled to room temperature to avoid rapid cooling that causes crystal structure destruction and stress accumulation.

[0019] As a preferred embodiment of the present invention, S6: functionalization treatment of the catalyst adopts a core-shell structure design, with a magnetic cobalt ferrite Fenton catalyst as the core and coated with a layer of functionalized shell, which can improve the stability and catalytic performance of the catalyst, wherein the functionalized shell adopts one of a metal oxide shell, a carbon material shell, a polymer shell and a silicone compound shell.

[0020] As a preferred embodiment of the present invention, S7: catalyst functionalization treatment is performed to perform performance testing on the prepared magnetic cobalt ferrite Fenton catalyst, including evaluation of catalytic activity and stability indicators.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The method for synthesizing the magnetic cobalt ferrite Fenton catalyst designed by the present invention comprises the following steps: raw material preparation, solution preparation, crystal precipitation preparation, stability adjustment, solid phase transformation, functionalization treatment and performance testing of the catalyst raw material. In the process of preparing the crystal precipitation, the co-precipitation method and the template method are used to synthesize the catalyst to control the growth rate and grain size of the crystal, thereby improving the uniformity of the grains. The growth direction and rate of the crystal can be controlled by the effect of the template, thereby obtaining more uniform grains. In addition, in the process of adjusting the catalyst stability, functional groups and coating agents with higher stability are introduced to protect the catalyst surface and prevent it from being damaged or inactivated during the reaction. DETAILED DESCRIPTION

[0023] A method for synthesizing a magnetic cobalt ferrite Fenton catalyst, wherein the specific synthesis steps are as follows:

[0024] S1: Catalyst raw material preparation and processing;

[0025] S2: catalyst solution preparation operation;

[0026] S3: Catalyst crystal precipitation preparation optimization process;

[0027] S4: catalyst stability adjustment and optimization treatment;

[0028] S5: catalyst solid phase transformation operation;

[0029] S6: Catalyst functionalization treatment;

[0030] S7: Finished catalyst performance test;

[0031] Through the above seven steps, the catalyst raw materials are sequentially subjected to raw material preparation, solution preparation, crystal precipitation preparation, stability adjustment, solid phase transformation, functionalization treatment and performance testing. In the process of crystal precipitation preparation, the co-precipitation method and the template method are used to synthesize the catalyst to control the growth rate and grain size of the crystal, thereby improving the uniformity of the grains. The growth direction and rate of the crystal can be controlled by the effect of the template, thereby obtaining more uniform grains. In addition, in the process of catalyst stability adjustment, functional groups and coating agents with higher stability are introduced to protect the catalyst surface and prevent it from being damaged or inactivated during the reaction.

[0032] S1: Preparation and processing of catalyst raw materials, including cobalt salt, iron salt, carrier material, surfactant and auxiliary agent, wherein the mass ratio of cobalt salt to iron salt is 3:1, the cobalt salt is cobalt chloride, the iron salt is ferric chloride, the carrier material is one of silicon dioxide and aluminum oxide, the auxiliary agent includes reducing agent, stabilizer and activator, these raw materials constitute the basic components of magnetic cobalt ferrite Fenton catalyst, through appropriate ratio and synthesis method, catalyst with good catalytic performance can be prepared, which can be used in the fields of organic wastewater treatment.

[0033] S2: dissolving the metal salt of the catalyst raw material prepared in step 1 in a mixing container to form a metal ion solution, and introducing a carrier material, a surfactant and an adjuvant into the solution to obtain a catalyst mixture. The catalyst usually needs to be carried on a carrier material to increase its surface area and stability. During the synthesis of the catalyst, it may be necessary to add a surfactant or a dispersant to control crystal growth and improve the dispersibility of the catalyst. During the preparation of the catalyst, it may be necessary to add other auxiliary substances, such as a reducing agent, a stabilizer, an activator, etc., to adjust the structure and performance of the catalyst.

[0034] S3: adding a precipitant and an alkaline solution to the catalyst mixture prepared in step 2 by a co-precipitation method to precipitate cobalt iron hydroxide in the solution, synthesizing the catalyst by a template method, and controlling the growth direction and rate of the crystals by the effect of the template, thereby obtaining more uniform grains.

[0035] S4: In the process of crystal formation in step 3, stable functional groups and capping agents are introduced to protect the catalyst surface, wherein the functional groups are selected from carboxyl and hydroxyl groups and the ratio of the two is 1:1.

[0036] S5: The crystalline material obtained above is precipitated and fixed on a carrier and introduced into a calcination container for calcination. The calcination temperature of the magnetic cobalt ferrite Fenton catalyst is controlled at 400°C to 800°C, and the calcination time is controlled at 1 hour to 4 hours. Nitrogen is introduced during the calcination process to protect the catalyst from oxidation. After the calcination, the catalyst is slowly cooled to room temperature to avoid rapid cooling that may cause crystal structure destruction and stress accumulation. During the calcination process, the magnetic cobalt ferrite Fenton catalyst is gradually heated at a rate of 100°C every 10 minutes.

[0037] S6: Catalyst functionalization treatment, using a core-shell structure design, with a magnetic cobalt ferrite Fenton catalyst as the core, covered with a layer of functionalized shell, can improve the stability and catalytic performance of the catalyst, wherein the functionalized shell is one of a metal oxide shell, a carbon material shell, a polymer shell and a siloxane compound shell. Different functionalized shells can be used according to the actual use needs of the catalyst to improve the use effect of the catalyst and improve the use environment.

[0038] S7: Catalyst functionalization treatment, performance testing of the prepared magnetic cobalt ferrite Fenton catalyst, including evaluation of catalytic activity and stability indicators.

[0039] The method for synthesizing the magnetic cobalt ferrite Fenton catalyst designed by the present invention comprises the following steps: raw material preparation, solution preparation, crystal precipitation preparation, stability adjustment, solid phase transformation, functionalization treatment and performance testing of the catalyst raw material. In the process of preparing the crystal precipitation, the co-precipitation method and the template method are used to synthesize the catalyst to control the growth rate and grain size of the crystal, thereby improving the uniformity of the grains. The growth direction and rate of the crystal can be controlled by the effect of the template, thereby obtaining more uniform grains. In addition, in the process of adjusting the catalyst stability, functional groups and coating agents with higher stability are introduced to protect the catalyst surface and prevent it from being damaged or inactivated during the reaction.

[0040] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for synthesizing a magnetic cobalt ferrite Fenton catalyst, characterized in that: The specific synthesis steps are as follows: S1: Catalyst raw material preparation and processing; S2: catalyst solution preparation operation; S3: Catalyst crystal precipitation preparation optimization process; S4: catalyst stability adjustment and optimization treatment; S5: catalyst solid phase transformation operation; S6: Catalyst functionalization treatment; S7: Finished catalyst performance test; Through the above seven steps, the catalyst raw materials are sequentially subjected to raw material preparation, solution preparation, crystal precipitation preparation, stability adjustment, solid phase transformation, functionalization treatment and performance testing. In the process of crystal precipitation preparation, the co-precipitation method and the template method are used to synthesize the catalyst to control the growth rate and grain size of the crystal, thereby improving the uniformity of the grains. The growth direction and rate of the crystal can be controlled by the effect of the template, thereby obtaining more uniform grains. In addition, in the process of catalyst stability adjustment, functional groups and coating agents with higher stability are introduced to protect the catalyst surface and prevent it from being damaged or inactivated during the reaction.

2. The method for synthesizing a magnetic cobalt ferrite Fenton catalyst according to claim 1, characterized in that: S1: Preparation and processing of catalyst raw materials, including cobalt salt, iron salt, carrier material, surfactant and auxiliary agent, wherein the mass ratio of cobalt salt to iron salt is 3:1, the cobalt salt is cobalt chloride, the iron salt is ferric chloride, the carrier material is one of silicon dioxide and aluminum oxide, and the auxiliary agent includes a reducing agent, a stabilizer and an activator.

3. The method for synthesizing a magnetic cobalt ferrite Fenton catalyst according to claim 1 is characterized in that: S2: dissolving the metal salt of the catalyst raw material prepared in step 1 in a mixing container to form a metal ion solution, and introducing a carrier material, a surfactant and an auxiliary agent into the solution to obtain a catalyst mixture.

4. The method for synthesizing a magnetic cobalt ferrite Fenton catalyst according to claim 1 is characterized in that: S3: adding a precipitant and an alkali solution to the catalyst mixture prepared in step 2 by a coprecipitation method to precipitate cobalt iron hydroxide in the solution, synthesizing the catalyst by a template method, and controlling the growth direction and rate of the crystal by the effect of the template.

5. The method for synthesizing a magnetic cobalt ferrite Fenton catalyst according to claim 1, characterized in that: S4: In the process of crystal formation in step 3, stable functional groups and capping agents are introduced to protect the catalyst surface, wherein the functional groups are selected from carboxyl and hydroxyl groups and the ratio of the two is 1:

1.

6. The method for synthesizing a magnetic cobalt ferrite Fenton catalyst according to claim 1 is characterized in that: S5: the crystalline material obtained above is precipitated and fixed on a carrier and introduced into a calcination container for calcination treatment, the calcination temperature of the magnetic cobalt ferrite Fenton catalyst is controlled at 400°C to 800°C, the calcination time is controlled at 1 hour to 4 hours, and nitrogen is introduced during the calcination process to protect the catalyst from oxidation. After the calcination is completed, the catalyst is slowly cooled to room temperature to avoid rapid cooling that causes crystal structure destruction and stress accumulation.

7. The method for synthesizing a magnetic cobalt ferrite Fenton catalyst according to claim 1, characterized in that: S6: Catalyst functionalization treatment, using a core-shell structure design, with a magnetic cobalt ferrite Fenton catalyst as the core and coated with a layer of functionalized shell, can improve the stability and catalytic performance of the catalyst, wherein the functionalized shell is one of a metal oxide shell, a carbon material shell, a polymer shell and a siloxane compound shell.

8. The method for synthesizing a magnetic cobalt ferrite Fenton catalyst according to claim 1, characterized in that: S7: Catalyst functionalization treatment, performance testing of the prepared magnetic cobalt ferrite Fenton catalyst, including evaluation of catalytic activity and stability indicators.