A preparation method and application of a biochar loaded transition metal catalyst

Abstract

The application provides a preparation method and application of a biochar loaded transition metal catalyst, and comprises the following steps: S1: after cleaning and processing, shiitake mushrooms are ground into powder, and a certain amount of nickel nitrate and sodium thiosulfate are added into deionized water and stirred and uniformly mixed to obtain a premix; S2: the premix obtained in S1 is placed in an oven and dried; S3: the premix treated through S2 is placed in a tube furnace and calcined under the protection of nitrogen to obtain the biochar loaded transition metal catalyst. The biochar skeleton is used as a carrier, the nickel nitrate and the sodium thiosulfate are used as active substances, and the biochar loaded transition metal catalyst is synthesized by using a high-temperature one-step method; the synthesis method is simple and is beneficial to large-scale promotion; the shiitake mushrooms are used as carbon sources, the biomass itself structure is used to load the catalytically active substances, the prepared catalyst has higher activity, and no noble metal is needed in the preparation process, so that the cost is lower.

Description

Technical Field

[0001] This invention belongs to the field of transition metal catalyst preparation technology, specifically relating to a method for preparing and applying a biochar-supported transition metal catalyst. Background Technology

[0002] Deuterium was initially used for military research, such as in the nuclear energy industry and nuclear weapons. However, with the development of technology, deuterium has gradually been used in civilian industries, such as in optical fiber materials and special light sources. Furthermore, deuterium can also be applied to sintering and annealing processes in the semiconductor and solar cell industries, as well as in nuclear fusion reactions, chemistry, and biochemistry. Therefore, research on deuterium preparation technology is of great significance.

[0003] Deuterium preparation technologies mainly include distillation, heavy water electrolysis, and gas chromatography. Among these, liquid hydrogen distillation requires a large amount of energy for the reflux section, resulting in significant energy consumption and unsatisfactory economic benefits. In gas chromatography, H₂-displacement chromatography offers high yields, recovery rates, and concentrations, but the process is relatively complex. Heading chromatography is relatively simple but suitable for preparing deuterium from natural hydrogen. Washing chromatography produces deuterium with lower purity, failing to meet current requirements.

[0004] The preparation of deuterium gas by electrolysis of heavy water mainly uses alkali metal deuterium oxides as electrolytes or solid polymers to electrolyze heavy water. Although the deuterium gas prepared by this technology has a high purity, it still needs further purification, and the energy consumed in the preparation process is also large. Therefore, an electrocatalyst that can produce high-purity deuterium gas using low voltage is needed. Summary of the Invention

[0005] The technical problem this invention aims to solve is to address the shortcomings of the prior art by providing a method for preparing and applying a biochar-supported transition metal catalyst. This method uses shiitake mushrooms as the carbon source and nickel nitrate and sodium thiosulfate as the catalytic active substances, employing a one-step calcination process to synthesize a biochar-supported transition metal catalyst for electrolytic deuteration. The synthesis method provided by this invention is simple to operate and has low cost, making it suitable for large-scale application.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a method for preparing a biochar-supported transition metal catalyst, characterized by comprising the following steps:

[0007] S1: Clean the shiitake mushrooms, grind them into powder, add a certain amount of nickel nitrate and sodium thiosulfate, then add deionized water and stir to mix evenly to obtain a premix.

[0008] S2: Place the premix obtained in S1 in an oven and dry it;

[0009] S3: The premix treated by S2 is placed in a tube furnace and calcined under nitrogen protection to obtain a biochar-supported catalyst.

[0010] Preferably, in S1, the mass ratio of shiitake mushrooms is 40%–80%, the mass ratio of nickel nitrate is 30%–10%, and the mass ratio of shiitake mushrooms is 30%–10%.

[0011] Preferably, in step S1, after cleaning the shiitake mushrooms, the shiitake mushrooms are cut into thin slices with a thickness of 0.3 cm. The shiitake mushroom slices are dried in an oven for 24 hours and then ground into powder. The oven temperature is 60℃~120℃.

[0012] Preferably, in step S2, the premix is ​​placed in an oven and baked for 12 hours at a temperature of 80°C.

[0013] Preferably, in S3, the initial operating temperature of the tubular furnace is 50°C, and the temperature is increased at 3°C / min. The maximum operating temperature is 500-800°C, preferably 600°C. After maintaining the maximum temperature for 1 hour, the temperature is gradually reduced to room temperature.

[0014] This invention provides the application of the biochar-supported transition metal catalyst obtained by the preparation method described above in the electrolysis of heavy water to produce deuterium.

[0015] The present invention relates to the application of the biochar-supported transition metal catalyst prepared in the electrolysis of heavy water to produce deuterium. The electrolysis device used for the electrolysis of heavy water is a diaphragmless electrolyzer, and a three-electrode system is used for the electrochemical reaction. The prepared biochar-supported transition metal catalyst is used as the working electrode, the platinum sheet electrode is used as the counter electrode, and the silver / silver chloride electrode is used as the reference.

[0016] Preferably, the prepared biochar-supported transition metal catalyst is mixed with Nafion solution and anhydrous ethanol. The mass fraction of Nafion solution is 5%, the volume ratio of Nafion solution to anhydrous ethanol is 1:5 to 10, and the mass ratio of biochar-supported transition metal catalyst to the sum of the volumes of Nafion solution and anhydrous ethanol is 5 to 10:100. The mass unit is mg, and the volume unit is μL.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] 1. The biochar-supported transition metal catalyst prepared by this invention uses a biochar framework as a support and nickel nitrate and sodium thiosulfate as active materials. It is synthesized in a one-step high-temperature method to produce deuterium by electrolysis. The synthesis method is simple and conducive to large-scale promotion.

[0019] 2. This invention uses shiitake mushrooms as a carbon source and utilizes the biomass' own structure to load catalytically active substances, resulting in a catalyst with higher activity. The preparation process does not require the use of precious metals, thus reducing costs and achieving higher economic benefits.

[0020] The present invention will be further described in detail below with reference to the embodiments. Attached Figure Description

[0021] Figure 1 This is a comparison chart of the rates of deuterium preparation in Examples 1-5 of the present invention.

[0022] Figure 2 The current density test diagram is shown when the biochar-supported transition metal catalyst prepared in this invention is used as the working electrode. Detailed Implementation

[0023] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described in detail below. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0024] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0025] Example 1

[0026] This invention provides a method for preparing a biochar-supported transition metal catalyst. Fresh shiitake mushrooms are cleaned and cut into thin slices with a thickness of 0.3 cm. The mushroom slices are dried in an oven at 80°C for 24 hours and then ground into powder. The dried mushroom slices are then ground into powder. 0.4 g of mushroom powder, 0.3 g of nickel nitrate, and 0.3 g of sodium thiosulfate are added to 3 ml of deionized water and mixed thoroughly to obtain a premix.

[0027] The premix was placed in an oven and baked for 12 hours at a temperature of 80°C.

[0028] The baked premix was placed in a tube furnace and calcined under nitrogen protection. The initial operating temperature of the tube furnace was 50℃, and the temperature was increased at 3℃ / min. The maximum operating temperature was 500℃. After being held at 500℃ for 1 hour, the temperature was gradually reduced to room temperature to obtain a biochar-supported transition metal catalyst.

[0029] 10 mg of the prepared biochar-supported transition metal catalyst was added to a mixture of 10 μL Nafion solution and 90 μL anhydrous ethanol to prepare a catalyst solution. This solution was then coated onto the surface of carbon cloth and dried using an infrared lamp. A three-electrode system was selected for the electrolytic cell. The generated catalytic electrode was used as the working electrode, the platinum sheet electrode as the counter electrode, and the silver / silver chloride electrode as the reference electrode. This assembled electrolytic system could produce 10.2 ml of deuterium gas per hour.

[0030] Example 2

[0031] This invention provides a method for preparing a biochar-supported transition metal catalyst. Fresh shiitake mushrooms are cleaned and cut into thin slices with a thickness of 0.3 cm. The mushroom slices are dried in an oven at 90°C for 24 hours and then ground into powder. The dried mushroom slices are then ground into powder. 0.6 g of mushroom powder, 0.15 g of nickel nitrate, and 0.25 g of sodium thiosulfate are added to 3 ml of deionized water and mixed thoroughly to obtain a premix.

[0032] The premix was placed in an oven and baked for 12 hours at a temperature of 80°C.

[0033] The baked premix was placed in a tube furnace and calcined under nitrogen protection. The initial operating temperature of the tube furnace was 50℃, and the temperature was increased at 3℃ / min. The maximum operating temperature was 600℃. After being held at 600℃ for 1 hour, the temperature was gradually reduced to room temperature to obtain a biochar-supported transition metal catalyst.

[0034] 10 mg of the prepared biochar-supported transition metal catalyst was added to a mixture of 8 μL Nafion solution and 70 μL anhydrous ethanol to prepare a catalyst solution. This solution was then coated onto the surface of carbon cloth and dried using an infrared lamp. A three-electrode system was selected for the electrolytic cell. The generated catalytic electrode was used as the working electrode, the platinum sheet electrode as the counter electrode, and the silver / silver chloride electrode as the reference electrode. This assembled electrolytic system could produce 12.6 ml of deuterium gas per hour.

[0035] Example 3

[0036] This invention provides a method for preparing a biochar-supported transition metal catalyst. Fresh shiitake mushrooms are cleaned and cut into thin slices with a thickness of 0.3 cm. The shiitake mushroom slices are dried in an oven at 80°C for 24 hours and then ground into powder. The dried shiitake mushroom slices are then ground into powder. 0.6 g of shiitake mushroom powder, 0.1 g of nickel nitrate, and 0.3 g of sodium thiosulfate are added to 3 ml of deionized water and stirred until homogeneous to obtain a premix.

[0037] The premix was placed in an oven and baked for 12 hours at a temperature of 80°C.

[0038] The baked premix was placed in a tube furnace and calcined under nitrogen protection. The initial operating temperature of the tube furnace was 50℃, and the temperature was increased at 3℃ / min. The maximum operating temperature was 600℃. After being held at 600℃ for 1 hour, the temperature was gradually reduced to room temperature to obtain a biochar-supported transition metal catalyst.

[0039] 10 mg of the prepared biochar-supported transition metal catalyst was added to a mixture of 10 μL Nafion solution and 90 μL anhydrous ethanol to prepare a catalyst solution. This solution was then coated onto the surface of carbon cloth and dried using an infrared lamp. A three-electrode system was selected for the electrolytic cell. The generated catalytic electrode was used as the working electrode, the platinum sheet electrode as the counter electrode, and the silver / silver chloride electrode as the reference electrode. This assembled electrolytic system could produce 13.8 ml of deuterium gas per hour.

[0040] Example 4

[0041] This invention provides a method for preparing a biochar-supported transition metal catalyst. Fresh shiitake mushrooms are cleaned and cut into thin slices with a thickness of 0.3 cm. The mushroom slices are dried in an oven at 80°C for 24 hours and then ground into powder. The dried mushroom slices are then ground into powder. 0.7 g of mushroom powder, 0.2 g of nickel nitrate, and 0.1 g of sodium thiosulfate are added to 3 ml of deionized water and mixed thoroughly to obtain a premix.

[0042] The premix was placed in an oven and baked for 12 hours at a temperature of 80°C.

[0043] The baked premix was placed in a tube furnace and calcined under nitrogen protection. The initial operating temperature of the tube furnace was 50℃, and the temperature was increased at 3℃ / min. The maximum operating temperature was 700℃. After being held at 700℃ for 1 hour, the temperature was gradually reduced to room temperature to obtain a biochar-supported transition metal catalyst.

[0044] Eight mg of the prepared biochar-supported transition metal catalyst was added to a mixture of 10 μL Nafion solution and 80 μL anhydrous ethanol to prepare a catalyst solution. This solution was then coated onto the surface of carbon cloth and dried using an infrared lamp. A three-electrode system was selected for the electrolytic cell. The generated catalytic electrode was used as the working electrode, the platinum sheet electrode as the counter electrode, and the silver / silver chloride electrode as the reference electrode. This assembled electrolytic system could produce 11.3 ml of deuterium gas per hour.

[0045] Example 5

[0046] This invention provides a method for preparing a biochar-supported transition metal catalyst. Fresh shiitake mushrooms are cleaned and cut into thin slices with a thickness of 0.3 cm. The mushroom slices are dried in an oven at 80°C for 24 hours and then ground into powder. The dried mushroom slices are then ground into powder. 0.8 g of mushroom powder, 0.1 g of nickel nitrate, and 0.1 g of sodium thiosulfate are added to 3 ml of deionized water and mixed thoroughly to obtain a premix.

[0047] The premix was placed in an oven and baked for 12 hours at a temperature of 80°C.

[0048] The baked premix was placed in a tube furnace and calcined under nitrogen protection. The initial operating temperature of the tube furnace was 50℃, and the temperature was increased at 3℃ / min. The maximum operating temperature was 800℃. After being held at 800℃ for 1 hour, the temperature was gradually reduced to room temperature to obtain a biochar-supported transition metal catalyst.

[0049] 10 mg of the prepared biochar-supported transition metal catalyst was added to a mixture of 10 μL Nafion solution and 90 μL anhydrous ethanol to prepare a catalyst solution. This solution was then coated onto the surface of carbon cloth and dried using an infrared lamp. A three-electrode system was selected for the electrolytic cell. The generated catalytic electrode was used as the working electrode, the platinum sheet electrode as the counter electrode, and the silver / silver chloride electrode as the reference electrode. This assembled electrolytic system could produce 8.2 ml of deuterium gas per hour.

[0050] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Any simple modifications, alterations, and equivalent changes made to the above embodiments based on the inventive essence shall still fall within the protection scope of the present invention.

Claims

1. A method for preparing a biochar-supported transition metal catalyst, characterized in that, Includes the following steps: S1: Clean the shiitake mushrooms, then cut them into thin slices with a thickness of 0.3cm. Dry the shiitake mushroom slices in an oven for 24 hours and then grind them into powder. The oven temperature is 60℃~120℃. Then grind the dried shiitake mushroom slices into powder, and add a certain amount of nickel nitrate and sodium thiosulfate. The mass ratio of shiitake mushrooms is 40%~80%, the mass ratio of nickel nitrate is 30%~10%, and the mass ratio of sodium thiosulfate is 30%~10%. Then add deionized water and stir to mix evenly to obtain a premix. S2: Place the premix obtained in S1 in an oven and bake for 12 hours at a temperature of 80°C. S3: The premix treated by S2 was placed in a tube furnace and calcined under nitrogen protection. The initial operating temperature of the tube furnace was 50℃, and the temperature was increased at 3℃ / min. The maximum operating temperature was 500~800℃. After holding at the maximum temperature for 1 hour, the temperature was gradually reduced to room temperature, and finally the biochar-supported transition metal catalyst was obtained.

2. The application of the biochar-supported transition metal catalyst obtained by the preparation method according to claim 1 in the electrolysis of heavy water to produce deuterium gas, characterized in that, The electrolysis device used for electrolysis of heavy water is a diaphragmless electrolytic cell, which uses a three-electrode system to carry out the electrochemical reaction. The prepared biochar-supported transition metal catalyst was added to a mixed solution of Nafion solution and anhydrous ethanol to prepare a catalyst solution. The solution was then coated onto the surface of the carbon cloth and dried with an infrared lamp to obtain a catalytic electrode. A platinum sheet electrode was used as the counter electrode and a silver / silver chloride electrode was used as the reference electrode. The mass fraction of the Nafion solution is 5%, the volume ratio of Nafion solution to anhydrous ethanol is 1:5~10, the mass ratio of the biochar-supported transition metal catalyst to the sum of the volumes of Nafion solution and anhydrous ethanol is 5~10:100, the mass unit is mg, and the volume unit is μL.

Images