CN108033521A - Load gamma MnO2Active carbon particle electrode preparation method and application - Google Patents

Abstract

The invention discloses a preparation method and application of an activated carbon particle electrode loaded with gamma _MnO2 . The method includes the following steps: filling activated carbon particles between the anode electrode plate and the cathode electrode plate, and at the same time, adding MnSO ₄ solution and H ₂ SO ₄ solution into the electrolytic cell; to the gap between the activated carbon particles; the electrolyzer is placed in a water bath at 70-80°C, and the electrodeposition is performed for 1-2h; after the end, the activated carbon particles are taken out, rinsed with water, and dried at 100-120°C for 24-48h to obtain gamma-loaded _MnO2 Activated carbon particle electrodes. Due to the adoption of the above-mentioned technical scheme, the oxygen source or the air source used in the method will not pollute the surrounding environment, and will not cause health damage to operating workers. Nano-gamma MnO ₂ with good electrocatalytic activity can be synthesized by hydrothermal method, and the economic cost is 2-3 times higher than that of electrodeposited gamma-like MnO ₂ .

Description

Preparation method and application of activated carbon particle electrode loaded with gamma MnO2

technical field

The invention belongs to the field of materials/electrochemical field/new energy field, and specifically relates to a preparation method and application of an activated carbon particle electrode loaded with gamma _MnO2 .

Background technique

Since entering the 21st century, environmental and energy issues are two important issues. The three-dimensional electrode reactor is often used as a treatment device for environmental wastewater. The principle is to use electrochemical oxidation to convert pollutants in wastewater into intermediate products, and finally into CO ₂ and H ₂ O. Among them, the activated carbon granular electrode is an important part of the three-dimensional electrode reactor (as described in Chinese patent CN02114740.X), and its electrocatalytic activity directly affects the efficiency of the three-dimensional electrode reactor for treating environmental wastewater. The better the catalytic activity of activated carbon, the higher the efficiency of the reactor in treating wastewater and the less energy consumption.

Gamma MnO ₂ is a safe, inexpensive and environmentally friendly electrocatalytic material. Compared with alpha MnO ₂ , beta MnO ₂ and theta MnO ₂ , it has higher voltage conversion rate, that is, higher electrocatalytic activity. Therefore, gamma _MnO2 is commonly used in the field of batteries. Gamma MnO ₂ is divided into three categories: natural MnO ₂ , chemically synthesized MnO ₂ (as described in published Chinese patent CN201610405132.1) and electrodeposited MnO ₂ . Among them, _MnO2 obtained by electrodeposition is easy to control, has high density, and has the highest electrocatalytic activity among the three. Although nano-gamma MnO ₂ with good electrocatalytic activity can be synthesized by hydrothermal method, the conditions are strict, high temperature and high pressure are required, and the economic cost is 2-3 times higher than that of electrodeposition-like gamma MnO ₂ times.

Contents of the invention

In view of this, _the present invention has deficiencies in the prior art, and provides a kind of preparation method of the activated carbon particle electrode of loaded gamma _MnO , the prepared activated carbon particle electrode of the loaded gamma MnO of it has good electrocatalytic activity , in a three-dimensional electrode reactor, the wastewater treatment efficiency is improved.

In order to achieve the above object, the present invention adopts the following technical scheme: a preparation method of gamma _MnO activated carbon particle electrode, the preparation method needs to use a stabilized power supply, an electrolytic cell, an anode electrode plate, a cathode electrode plate, a gas Uniform distribution plate and water bath device, described method comprises the steps:

Step 1: Fill activated carbon particles between the anode electrode plate and the cathode electrode plate, and at the same time, add the mixed solution of MnSO ₄ solution and H ₂ SO ₄ solution into the electrolytic cell as the electrolyte;

Step 2. Carry out electrodeposition reaction: switch on the circuit with a certain voltage or current density, pass in a certain concentration of oxygen, and evenly disperse to the gap between the activated carbon particles through the gas uniform distribution plate;

Step 3: The electrolytic cell is in a water bath heating state, and electrodeposition is performed for a period of time;

Step 4: After the electrodeposition is completed, take out the activated carbon particles, rinse them with water, remove the unreacted MnSO ₄ solution and H ₂ SO ₄ solution on the surface of the activated carbon particles, and dry them at a suitable temperature for a period of time to obtain the loaded gamma MnO ₂ activated carbon particle electrodes.

Further, the ratio of the MnSO ₄ solution and the H ₂ SO ₄ solution in the step 1 is: the concentration of the MnSO ₄ solution is 100-120 g/L, and the concentration of the H ₂ SO ₄ is 20-40 g/L.

Further, the activated carbon particles are coconut shells and/or fruit shells; the activated carbon particles are block particles or columnar particles; the particle size of the block particles is 2-4mm; the particle size of the columnar particles is 2mm, 4mm and 6mm; the raw material of activated carbon particles is one or a combination of coconut shell and fruit shell.

Further, the material of the anode electrode plate is: Ti/RuO ₂ electrode plate or Pt electrode plate; the material of the cathode electrode plate is: stainless steel electrode plate, glass carbon electrode plate, Cu electrode plate or graphite electrode plate.

Further, the distance between the anode electrode plate and the cathode electrode plate is 3-10 cm.

Further, the heating temperature of the water bath in the step 3 is 70-80°C, the electrodeposition time is 1-2h, and the gas introduced is one or two of high-purity oxygen and air.

Further, the voltage of the electrodeposition reaction in the step 2 is 10-20V, or the current density is 50-100mA/cm ² .

Further, the water used for washing the activated carbon particles in step 4 is deionized water, distilled water or ultrapure water.

Further, the drying temperature in step 4 is: 100-120°C; the drying time is: 24-48h.

An activated carbon particle electrode loaded with gamma _MnO2 prepared by the above method is applied to fill the cathode and anode chambers of a three-dimensional electrode reactor, and acts as a particle electrode to increase electrocatalytic activity and improve wastewater treatment efficiency.

The beneficial effects of the present invention are: due to the above-mentioned technical scheme, the present invention has the following characteristics:

(1) The use of oxygen source or air source will not pollute the surrounding environment, nor will it cause health damage to the operators, and the exhaust gas obtained can be collected and used again for electrodeposition. The invention realizes resource utilization of remaining oxygen by utilizing the vented oxygen generated when nitrogen and argon are produced by air separation devices in petrochemical, chemical, steel, electric power and other industries.

(2) Nano-gamma MnO ₂ with good electrocatalytic activity can be synthesized by hydrothermal method, but the conditions are strict, high temperature and high pressure are required, and the economic cost is _2- 3 times.

Description of drawings

Fig. 1 is a schematic diagram of the preparation device of the activated carbon particle electrode loaded with gamma _MnO2 of the present invention.

Figure 2 shows the removal rate of wastewater TOC by a three-dimensional electrode reactor using gamma- _MnO2 -loaded activated carbon granular electrodes.

Figure 3 is the removal rate of wastewater chromaticity by the three-dimensional electrode reactor using the activated carbon particle electrode loaded with gamma _MnO2 .

In the picture:

1. Stabilized power supply, 2. Electrolyzer,

3. Anode electrode plate, 4. Cathode electrode plate,

5. Gas uniform distribution plate, 6. Water bath device,

7. Activated carbon particles.

Detailed ways

Embodiments of the invention are described in detail below, examples of which are illustrated in the accompanying drawings, in which throughout

The same or similar reference numerals denote the same or similar elements or elements having the same or similar functions. The embodiments described below by referring to the figures are exemplary only for explaining the present invention and should not be construed as limiting the present invention.

These and other aspects of embodiments of the invention will become apparent with reference to the following description and drawings. in these descriptions

In the drawings and drawings, some specific implementation manners in the embodiments of the present invention are specifically disclosed to represent some ways of implementing the principles of the embodiments of the present invention, but it should be understood that the scope of the embodiments of the present invention is not limited thereto. On the contrary, the embodiments of the present invention include all changes, modifications and equivalents coming within the spirit and scope of the appended claims.

As shown in Figure 1, a kind of preparation method of the activated carbon granular electrode of the present invention load gamma _MnO , described preparation method needs to use stabilized voltage power supply, electrolyzer, anode electrode plate, cathode electrode plate, gas evenly distributed plate and water bath device, the method includes the steps of:

Step 1: Fill activated carbon particles between the anode electrode plate and the cathode electrode plate, and at the same time, add the mixed solution of MnSO ₄ solution and H ₂ SO ₄ solution into the electrolytic cell as the electrolyte;

Step 2. Carry out electrodeposition reaction: switch on the circuit with a certain voltage or current density, pass in a certain concentration of oxygen, and evenly disperse to the gap between the activated carbon particles through the gas uniform distribution plate;

Step 3: The electrolytic cell is in a water bath heating state, and electrodeposition is performed for a period of time;

Step 4: After the electrodeposition is completed, take out the activated carbon particles, rinse them with water, remove the unreacted MnSO ₄ solution and H ₂ SO ₄ solution on the surface of the activated carbon particles, and dry them at a suitable temperature for a period of time to obtain the loaded gamma MnO ₂ activated carbon particle electrodes.

The ratio of the MnSO ₄ solution and the H ₂ SO ₄ solution in the step 1 is: the concentration of the MnSO ₄ solution is 100-120 g/L, and the concentration of the H ₂ SO ₄ is 20-40 g/L.

The activated carbon particles are coconut shells and/or fruit shells; the activated carbon particles are block particles or columnar particles; the particle diameter of the block particles is 2-4mm; the particle diameter of the column particles is 2mm, 4mm and 6mm; the raw material of activated carbon particles is one or a combination of coconut shell and fruit shell.

The material of the anode electrode plate is: Ti/RuO ₂ electrode plate or Pt electrode plate; the material of the cathode electrode plate is: stainless steel electrode plate, glass carbon electrode plate, Cu electrode plate or graphite electrode plate.

The distance between the anode electrode plate and the cathode electrode plate is 3-10 cm.

The heating temperature of the water bath in the step 3 is 70-80° C., the electrodeposition time is 1-2 h, and the gas introduced is one or two of high-purity oxygen and air.

The voltage of the electrodeposition reaction in the step 2 is 10-20V, or the current density is 50-100mA/cm ² .

The water used for flushing the activated carbon particles in step 4 is deionized water, distilled water or ultrapure water.

Further, the drying temperature in step 4 is: 100-120°C; the drying time is: 24-48h.

An activated carbon particle electrode loaded with gamma _MnO2 prepared by the above method is applied to fill the cathode and anode chambers of a three-dimensional electrode reactor, and acts as a particle electrode to increase electrocatalytic activity and improve wastewater treatment efficiency.

Example 1

A kind of preparation method of the activated carbon granular electrode of load _gamma MnO , comprises the steps:

1) Activated carbon particles are filled between the anode electrode plate and the cathode electrode plate, and the distance between the plates is 8cm. At the same time, add 80g/L MnSO ₄ solution and 20g/L H ₂ SO ₄ solution into the electrolytic cell, wherein the activated carbon is a block particle, the raw material is coconut shell, and the particle size is 2-4mm;

2) Electrodeposition reaction is carried out, that is, the circuit is connected, the voltage is 10V, high-purity oxygen is introduced, and the gas uniform distribution plate is evenly dispersed to the gap between the activated carbon particles; the electrolytic cell is placed in a water bath at 80 ° C, and the electrodeposition is 1h;

3) After the electrodeposition is completed, take out the activated carbon particles, rinse them with deionized water, remove the unreacted MnSO ₄ solution and H ₂ SO ₄ solution on the surface of the activated carbon particles, and dry them at 120°C for 24 hours to obtain gamma-loaded MnO ₂ activated carbon particle electrodes.

Example 2

A kind of preparation method of the activated carbon granular electrode of load _gamma MnO , comprises the steps:

1) Activated carbon particles are filled between the anode electrode plate and the cathode electrode plate, and the distance between the plates is 8cm. At the same time, add 80g/L MnSO ₄ solution and 20g/L H ₂ SO ₄ solution into the electrolytic cell, wherein the activated carbon is a block particle, the raw material is coconut shell, and the particle size is 2-4mm;

2) Electrodeposition reaction is carried out, that is, the circuit is connected, the voltage is 15V, high-purity oxygen is introduced, and the gas uniform distribution plate is evenly dispersed to the gap between the activated carbon particles; the electrolytic cell is in a water bath at 80 ° C, and the electrodeposition is 1h;

3) After the electrodeposition is completed, take out the activated carbon particles, rinse them with deionized water, remove the unreacted MnSO ₄ solution and H ₂ SO ₄ solution on the surface of the activated carbon particles, and dry them at 120°C for 24 hours to obtain gamma-loaded MnO ₂ activated carbon particle electrodes.

Example 3

A kind of preparation method of the activated carbon granular electrode of load _gamma MnO , comprises the steps:

1) Activated carbon particles are filled between the anode electrode plate and the cathode electrode plate, and the distance between the plates is 8cm. At the same time, add 80g/L MnSO ₄ solution and 20g/L H ₂ SO ₄ solution into the electrolytic cell, wherein the activated carbon is a block particle, the raw material is coconut shell, and the particle size is 2-4mm;

2) Electrodeposition reaction is carried out, that is, the circuit is connected, the voltage is 20V, high-purity oxygen is introduced, and the gas uniform distribution plate is evenly dispersed to the gap between the activated carbon particles; the electrolytic cell is placed in a water bath at 80°C, and the electrodeposition is 1h;

3) After the electrodeposition is completed, take out the activated carbon particles, rinse them with deionized water, remove the unreacted MnSO ₄ solution and H ₂ SO ₄ solution on the surface of the activated carbon particles, and dry them at 120°C for 24 hours to obtain gamma-loaded MnO ₂ activated carbon particle electrodes.

comparative example

Use unloaded gamma _MnO2 activated carbon block particles, raw material is coconut shell, particle size 2-4mm;

Comparison of treatment effects of three-dimensional electrode reactor on rhodamine B simulated dye wastewater. Among them, the concentration of rhodamine B is 100mg/L, the treatment capacity is 500mL, the electrolyte is Na ₂ SO ₄ 2g/L, the hydraulic retention time is 20min, the electrolysis voltage is 5V, the distance between the plates is 3cm, and the amount of activated carbon particle electrode is 80g (adsorption saturation has been reached), Electrolysis time 3h. The electrocatalytic activity of the gamma MnO ₂ activated carbon particle electrode was characterized by the removal rate of the wastewater TOC and chromaticity, as shown in Figure 2 and Figure 3 below.

It can be seen from the above figure that the preparation method and application of an activated carbon particle electrode loaded with gamma MnO ₂ according to the present invention greatly improves the electrocatalytic activity of the activated carbon particle electrode by loading gamma MnO ₂ . In the electrode reactor, the wastewater treatment efficiency is improved.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the technical scope of the present invention. Therefore, any minor modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention are valid. Still belong to the scope of the technical solution of the present invention.

Claims (10)

1. one kind load gamma MnO₂Active carbon particle electrode preparation method, it is characterised in that the preparation method needs to make Use regulated power supply（1）, electrolytic cell（2）, anode electrode plate（3）, cathode electrode plate（4）, even gas distribution plate（5）And water bath device （6）, the described method includes have the following steps：

Step 1：By active carbon particle（7）It is filled in anode electrode plate（3）And cathode electrode plate（4）Between, meanwhile, electrolytic cell （2）Middle addition MnSO₄Solution and H₂SO₄The mixed solution of solution is electrolyte；

Step 2. carries out electrodeposit reaction:Circuit is connected with certain voltage or current density, is passed through certain density oxygen, is led to Cross even gas distribution plate（5）Evenly spread to active carbon particle（7）Gap；

Step 3：Electrolytic cell（2）In heating water bath state, electro-deposition is carried out for a period of time；

Step 4：After electro-deposition, active carbon particle is taken out（7）, rinsed with water, remove active carbon particle（7）Surface unreacted Complete MnSO₄Solution and H₂SO₄Solution, and dry a period of time at a suitable temperature, that is, obtain load gamma MnO₂Activity Charcoal mosaic electrode.

2. preparation method according to claim 1, it is characterised in that MnSO in the step 1₄Solution and H₂SO₄Solution is matched somebody with somebody Than for：MnSO₄The concentration of solution is 100-120g/L, H₂SO₄Concentration be 20-40g/L.

3. preparation method according to claim 1, it is characterised in that the active carbon particle（7）For coconut husk and/or fruit Shell；The active carbon particle（7）For blocky-shaped particle or cylindrical particle；The particle diameter of the blocky-shaped particle is 2-4mm；The column The particle diameter of grain is 2mm, 4mm and 6mm；The raw material of active carbon particle for coconut husk and shell a kind of or both composition.

4. preparation method according to claim 1, it is characterised in that the anode electrode plate（3）Material is：Ti/RuO₂Electricity Pole plate or Pt electrode plates；The cathode electrode plate（4）Material is：Stainless steel electrode plate, glassy carbon electrode plate, Cu electrode plates or stone Electrode ink plate.

5. load gamma MnO according to claim 1₂Active carbon particle electrode preparation method, it is characterised in that institute State anode electrode plate（3）With the cathode electrode plate（4）Between spacing be 3-10cm.

6. preparation method according to claim 1, it is characterised in that the water bath heating temperature in the step 3 is 70-80 DEG C, electrodeposition time 1-2h, the gas being passed through is high purity oxygen gas, one or two kinds of in air.

7. preparation method according to claim 1, it is characterised in that the voltage of electrodeposit reaction is 10- in the step 2 20V, or current density are 50-100mA/cm²。

8. preparation method according to claim 1, it is characterised in that rinsed in the step 4 used in active carbon particle Water is deionized water, distilled water or ultra-pure water.

9. preparation method according to claim 1, it is characterised in that drying temperature is in the step 4：100-120℃； Drying time is：24-48h.

A kind of 10. load gamma MnO being prepared such as any one of claim 1-9₂Active carbon particle application of electrode in filling To 3 D electrode reactor the anode chamber and the cathode chamber, mosaic electrode is served as, increases electro catalytic activity, improves waste water treatment efficiency.