Method for green preparation of water gas by utilizing silicon dioxide piezoelectric catalysis CO2 reduction
By modifying silica piezoelectric catalysts and Fe element doping, the high energy consumption and high pollution problems of traditional water gas preparation are solved, and low-energy and environmentally friendly water gas preparation and carbon dioxide absorption are achieved. The catalyst is easy to obtain and suitable for large-scale production.
Patent Information
- Application Number
- CN202511134415.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-14
- Publication Date
- 2025-10-17
AI Technical Summary
Traditional water gas preparation technology has problems of high energy consumption and high pollution, and the piezoelectric properties of traditional piezoelectric catalysts need to be further improved to improve catalytic efficiency.
Silica is used as a catalyst and modified by Fe element doping. CO2 is reduced to H2 and CO in combination with piezoelectric catalysis. Iron-doped silica is prepared by mechanochemical method to improve the piezoelectric performance and realize green preparation of water gas.
It realizes the low-energy and environmentally friendly water gas preparation while absorbing carbon dioxide. The catalyst is widely available and inexpensive, making it suitable for large-scale preparation.
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Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of piezoelectric catalytic carbon reduction, and particularly relates to a green preparation method of water gas by using piezoelectric catalysis of silicon dioxide to reduce CO2. BACKGROUND
[0002] Water gas is a combustible mixed gas composed of carbon monoxide (CO) and hydrogen (H2), which is usually generated by the reaction of coal or coke with water vapor at high temperature, and has high chemical reactivity. As an important intermediate product of clean conversion of coal, water gas is widely used in the preparation of basic chemical raw materials such as ammonia, methanol, olefins, and liquid fuels, and is also a key raw gas in the processes of coal hydrogen production and gasification power generation, playing an important role in ensuring energy security and promoting efficient use of coal resources. At present, the industrial preparation of water gas mainly includes three technical routes: fixed bed gasification, fluidized bed gasification and coal water slurry gasification. The fixed bed gasification process is simple in structure and stable in operation, and is suitable for small and medium scale production; the fluidized bed gasification has high reaction intensity and is suitable for a wide range of coal, and is suitable for medium scale modernization device; and the coal water slurry gasification uses coal water mixture as raw material, which can realize continuous and automatic operation, and the gas composition is stable, which is suitable for large coal chemical projects. Among them, the coal water slurry gasification technology is currently the most widely used, because it has strong process flexibility, good raw material adaptability, and can realize efficient heat utilization and process control, especially suitable for the demand of large chemical enterprises for stable gas source and high automation level, and has become the mainstream choice of modern coal gasification device.
[0003] At present, the preparation of water gas in industry usually adopts intermittent fixed bed gasification process, which reacts coal or coke with water vapor at high temperature to generate water gas. Since the reaction is a strong endothermic process, air is periodically introduced to burn coal to supplement heat, forming an operation mode of alternating blast and steam. Although this method is simple in process and wide in raw materials, it also has many disadvantages: high energy consumption, low thermal efficiency, strong reaction intermittency, difficult to realize continuous and stable operation, and also accompanied by a large amount of emission of pollutants such as carbon dioxide, nitrogen oxides, sulfides and tar, which brings great environmental pressure. With the promotion of the "double carbon" goal, the traditional water gas preparation process needs to be transformed and upgraded to green, efficient and clean direction as soon as possible.
[0004] Piezoelectric catalysis is a new green catalytic technology emerging in recent years, which can convert various natural energy (such as tidal energy, wind energy, etc.) into storable chemical energy through piezoelectric effect, and has the advantages of high catalytic efficiency, simple operation, green and environmental protection. However, how to improve the piezoelectric performance of traditional piezoelectric catalysts and improve the catalytic efficiency is still a problem to be solved. SUMMARY
[0005] In order to overcome the above-mentioned deficiencies of the prior art, the present application provides a green preparation of water gas by using silicon dioxide piezoelectric catalysis of CO2 reduction, the present application selects one of the most abundant substances in nature, namely silicon dioxide, as a catalyst, reduces CO2 to H2 and CO through piezoelectric catalysis, and further improves the piezoelectric performance through Fe element doping modification to improve the piezoelectric catalysis efficiency, and realizes the absorption of CO2 and the preparation of water gas, and solves the problems of high energy consumption and high pollution in the traditional water gas preparation technology.
[0006] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is:
[0007] The present application provides a green preparation of water gas by using silicon dioxide piezoelectric catalysis of CO2 reduction, the method comprising the following steps:
[0008] Silicon dioxide piezoelectric catalyst and ultrapure water are added to the reactor, CO2 gas is introduced to replace the air in the reactor chamber, and mechanical force is continuously applied to promote the reaction.
[0009] Further, the silicon dioxide piezoelectric catalyst is crystalline silicon dioxide, which includes single crystal silicon dioxide, polycrystalline silicon dioxide and iron-doped silicon dioxide.
[0010] Further, the preparation method of the iron-doped silicon dioxide is as follows: the silicon dioxide is put into a stainless steel ball mill jar, stainless steel ball milling beads and anhydrous ethanol are put in, and the planetary jar ball mill is put into the planetary jar ball mill, and after ball milling, the iron-doped silicon dioxide is obtained after cleaning and drying.
[0011] Further, the ball milling speed is 350 rpm, and the ball milling time is 24 h.
[0012] Further, the mass of silicon dioxide in the stainless steel ball mill jar is 1-5 g, the diameter of the stainless steel ball milling beads is 5 mm, the number of the stainless steel ball milling beads is 20-50, and the volume of the anhydrous ethanol is 10-50 mL.
[0013] Further, the CO2 gas inlet pressure is 1 bar-10 bar.
[0014] Further, the mass ratio of the silicon dioxide piezoelectric catalyst to the ultrapure water is 1:1-1:50.
[0015] Further, the mechanical force is applied in the form of ultrasonic, ball milling or stirring.
[0016] The second aspect of the present application provides a reactor for the above-mentioned method for green preparation of water gas by silica piezoelectric catalytic reduction of CO2, which is an ultrasonic piezoelectric catalytic reactor, a ball milling piezoelectric catalytic reactor or a stirring reactor, the reaction cavity of the ultrasonic piezoelectric catalytic reactor adopts a whole sealing structure, is provided with a pressure monitoring valve, the top cover is provided with two gas valves for input of CO2 gas and output of water gas respectively, and an ultrasonic rod is reserved in a hole of the top cover to realize ultrasonic effect.
[0017] Further, the reaction cavity of the ball milling piezoelectric catalytic reactor adopts a whole sealing structure, is provided with a pressure monitoring valve, the top cover is provided with two gas valves for input of CO2 gas and output of water gas respectively, and ball milling beads are placed in the cavity, and the ball milling process is realized by transversely placing and rotating the drum type cavity.
[0018] Further, the reaction cavity of the stirring piezoelectric catalytic reactor adopts a whole sealing structure, is provided with a pressure monitoring valve, the top cover is provided with two gas valves for input of CO2 gas and output of water gas respectively, and blades and a motor are installed at the bottom of the reaction cavity for controlling rotation of the blades and stirring.
[0019] Compared with the prior art, the present application has the following advantages:
[0020] The present application provides a method for green preparation of water gas by silica piezoelectric catalytic reduction of CO2, which selects silica, one of the most abundant substances in nature, as a catalyst, reduces CO2 to H2 and CO through piezoelectric catalysis, and further improves the piezoelectric performance and piezoelectric catalytic efficiency by doping and modifying the Fe element, realizes absorption of CO2 and preparation of water gas, and solves the problems of high energy consumption and high pollution in traditional water gas preparation technology. Specifically, the present application has the following advantages:
[0021] (1) The catalyst of the present application is widely available, low in price and easy to obtain;
[0022] (2) The present application further improves the piezoelectric performance and piezoelectric catalytic efficiency by preparing iron-doped silica through a simple mechanical-chemical method of stainless steel ball milling beads;
[0023] (3) The process of the present application is simple and low in energy consumption, and is suitable for large-scale preparation;
[0024] (4) The water gas preparation process of the present application is green and environmentally friendly, and realizes efficient absorption of CO2 while synthesizing water gas. BRIEF DESCRIPTION OF DRAWINGS
[0025] Figure 1 The ultrasonic piezoelectric catalytic reactor in Example 1, Example 2 and Example 3 is shown in the schematic diagram;
[0026] Figure 2 Schematic diagram of ball-milling piezocatalytic reactor in Example 4;
[0027] Figure 3 Schematic diagram of stirring piezocatalytic reactor in Example 5;
[0028] Figure 4 XRD patterns of polycrystalline silicon dioxide (p-SiO2) in Example 2, Example 5, monocrystalline silicon dioxide (m-SiO2) in Example 1, Example 4, and iron-doped silicon dioxide (Fe-SiO2) in Example 3;
[0029] Figure 5 Quantitative analysis results of water gas prepared in Examples 1-5. DETAILED DESCRIPTION
[0030] The specific embodiments of the present application are described below. It should be noted that the description of these embodiments is intended to help understand the present application, but does not constitute a limitation on the present application. In addition, the technical features involved in each of the embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.
[0031] The experimental methods in the following examples are all conventional methods unless otherwise specified. The test materials used in the following examples are all commercially available unless otherwise specified.
[0032] Example 1: Preparation of water gas by ultrasonic piezocatalytic reduction of carbon dioxide using monocrystalline silicon dioxide
[0033] (1) Monocrystalline silicon dioxide (m-SiO2) purchased was selected as the piezocatalyst. The monocrystalline silicon dioxide was crushed and washed with acetone, ethanol, and ultrapure water, and then dried to obtain monocrystalline silicon dioxide powder.
[0034] (2) Ultrasonic was selected to apply mechanical force to the catalyst, and piezocatalytic reaction was carried out in an ultrasonic piezocatalytic reactor. The reaction cavity of the ultrasonic piezocatalytic reactor adopts a whole sealing structure, is provided with a pressure monitoring valve, and the top cover is provided with two gas valves for inputting CO2 gas and outputting water gas, respectively. In addition, an ultrasonic rod is installed in a reserved hole to realize ultrasonic action. The schematic diagram of the ultrasonic piezocatalytic reactor is shown in Figure 1 .
[0035] (3) Monocrystalline silicon dioxide powder and ultrapure water with a mass ratio of 1:50 were added into the ultrasonic piezocatalytic reactor, 1.5 bar of CO2 gas was introduced to replace the air in the cavity, and ultrasonic (power 400 W, frequency 20 kHz) was continuously applied to promote the reaction. The gas produced in the reaction was collected by a gas bag, and the composition was analyzed by a gas chromatograph.
[0036] Example 2: Preparation of water gas by ultrasonic piezocatalytic reduction of carbon dioxide with polycrystalline silicon dioxide
[0037] (1) Polycrystalline silicon dioxide (p-SiO2) was selected as the piezocatalyst and was washed with acetone, ethanol, and ultrapure water and dried to obtain polycrystalline silicon dioxide powder.
[0038] (2) Ultrasonic waves were selected to apply mechanical force to the catalyst, and piezocatalytic reaction was carried out in an ultrasonic piezocatalytic reactor. The reaction cavity of the ultrasonic piezocatalytic reactor was of a whole closed structure, was equipped with a pressure monitoring valve, and the top cover was provided with two gas valves for inputting CO2 gas and outputting water gas, respectively. In addition, a hole was reserved for installing an ultrasonic rod to realize ultrasonic action. The schematic diagram of the ultrasonic piezocatalytic reactor is shown in Figure 1 .
[0039] (3) Polycrystalline silicon dioxide powder and ultrapure water with a mass ratio of 1:50 were added into the ultrasonic piezocatalytic reactor, 1.5 bar of CO2 gas was introduced to replace the air in the cavity, and ultrasonic waves (power 400 W, frequency 20 kHz) were continuously applied to promote the reaction. The gas produced in the reaction was collected by a gas bag, and gas chromatography was used for component analysis.
[0040] Example 3: Preparation of water gas by ultrasonic piezocatalytic reduction of carbon dioxide with iron-doped silicon dioxide
[0041] (1) The purchased single-crystal silicon dioxide was crushed and washed with acetone, ethanol, and ultrapure water and dried to obtain single-crystal silicon dioxide powder. The single-crystal silicon dioxide was doped by a mechanical-chemical method. 5 g of single-crystal silicon dioxide powder was placed in a stainless steel ball mill jar, 20 stainless steel ball milling beads with a diameter of 5 mm and 20 mL of anhydrous ethanol were added, and the ball mill jar was sealed and placed in a planetary jar mill. The ball milling speed was set to 350 rpm, and the ball milling time was 24 h. The appearance of the obtained iron-doped silicon dioxide (Fe-SiO2) was gray, and it was further washed and dried to obtain iron-doped silicon dioxide powder.
[0042] (2) Ultrasonic waves were selected to apply mechanical force to the catalyst, and piezocatalytic reaction was carried out in an ultrasonic piezocatalytic reactor. The reaction cavity of the ultrasonic piezocatalytic reactor was of a whole closed structure, was equipped with a pressure monitoring valve, and the top cover was provided with two gas valves for inputting CO2 gas and outputting water gas, respectively. In addition, a hole was reserved for installing an ultrasonic rod to realize ultrasonic action. The schematic diagram of the ultrasonic piezocatalytic reactor is shown in Figure 1 .
[0043] (3) The ultrasonic piezocatalytic reactor was filled with iron-doped silicon dioxide powder and ultrapure water at a mass ratio of 1:50, 1.5 bar of CO2 gas was introduced to replace the air in the chamber, and ultrasonic waves (power 400 W, frequency 20 kHz) were continuously applied to promote the reaction. The gas produced by the reaction was collected by a gas bag, and the composition was analyzed by gas chromatography.
[0044] Example 4: Single-crystal silicon dioxide ball-milling piezocatalytic reduction of carbon dioxide to produce water gas
[0045] (1) Single-crystal silicon dioxide (m-SiO2) purchased was selected as the piezocatalyst, and the single-crystal silicon dioxide was crushed and washed with acetone, ethanol, and ultrapure water before drying to obtain single-crystal silicon dioxide powder.
[0046] (2) Ball-milling was selected to apply mechanical force to the catalyst, and the piezocatalytic reaction was carried out in a ball-milling piezocatalytic reactor. The reaction chamber of the ball-milling piezocatalytic reactor has a whole-closed structure, is equipped with a pressure monitoring valve, and has two gas valves on the top cover for the input of CO2 gas and the output of water gas. Ball beads are placed inside the chamber, and the ball-milling process is realized by placing the drum-type chamber horizontally and rotating it. The schematic diagram of the ball-milling piezocatalytic reactor is shown in Figure 2 .
[0047] (3) The ball-milling piezocatalytic reactor was filled with single-crystal silicon dioxide powder and ultrapure water at a mass ratio of 1:5, 1.5 bar of CO2 gas was introduced to replace the air in the chamber, and continuous ball-milling (speed 300 rpm, time 24 h) was applied to promote the reaction. The gas produced by the reaction was collected by a gas bag, and the composition was analyzed by gas chromatography.
[0048] Example 5: Polycrystalline silicon dioxide stirring piezocatalytic reduction of carbon dioxide to produce water gas
[0049] (1) Polycrystalline silicon dioxide (p-SiO2) purchased was selected as the piezocatalyst, and the polycrystalline silicon dioxide powder was washed with acetone, ethanol, and ultrapure water before drying to obtain polycrystalline silicon dioxide powder.
[0050] (2) Stirring was selected to apply mechanical force to the catalyst, and the piezocatalytic reaction was carried out in a stirring piezocatalytic reactor. The reaction chamber of the stirring piezocatalytic reactor has a whole-closed structure, is equipped with a pressure monitoring valve, and has two gas valves on the top cover for the input of CO2 gas and the output of water gas. The reaction chamber is installed with blades and a motor at the bottom for controlling the rotation of the blades and stirring. The schematic diagram of the stirring piezocatalytic reactor is shown in Figure 3 .
[0051] (3) Polycrystalline silicon dioxide powder and ultrapure water with a mass ratio of 1:20 were added into the stirring piezoelectric catalytic reactor, 1.5 bar CO2 gas was introduced to replace the air in the chamber, and continuous stirring (rotation speed 6000 rpm, time 4 h) was performed to promote the reaction. The gas produced by the reaction was collected by a gas bag, and the composition was analyzed by a gas chromatograph.
[0052] The XRD patterns of the single-crystal silicon dioxide, polycrystalline silicon dioxide and iron-doped silicon dioxide in the above examples are shown in Figure 4 Figure 4 It can be seen that the main phase composition of the three is silicon dioxide, and the single-crystal and polycrystalline silicon dioxide have no other impurity components, while the iron-doped silicon dioxide has an XRD characteristic peak of elemental iron at 44°, indicating the successful doping of iron elements.
[0053] The water gas quantitative analysis results prepared in Example 15 are shown in Figure 5 Figure 5 It can be seen that the SiO2 piezoelectric catalysis can successfully convert CO2 absorption into water gas (H2, CO, CH4), realizing the green preparation of water gas; and the doped Fe silicon dioxide has higher performance due to the increased lattice distortion.
[0054] The embodiments of the present application are described in detail above, but the present application is not limited to the described embodiments. For those skilled in the art, various changes, modifications, replacements and variations of the embodiments can be made without departing from the principles and spirits of the present application, and still fall within the protection scope of the present application.
Claims
1. A green method for preparing water gas by using silicon dioxide piezoelectric catalysis to reduce CO2, characterized in that: The method comprises the following steps: Silica piezoelectric catalyst and ultrapure water were added to the reactor, CO2 gas was introduced to replace the air in the reactor chamber, and mechanical force was continuously applied to promote the reaction.
2. The green method for preparing water gas by using silicon dioxide piezoelectric catalysis to reduce CO2 according to claim 1, characterized in that: The silicon dioxide piezoelectric catalyst is crystalline silicon dioxide, and the crystalline silicon dioxide includes single crystal silicon dioxide, polycrystalline silicon dioxide and iron-doped silicon dioxide.
3. The green method for preparing water gas by using silicon dioxide piezoelectric catalysis to reduce CO2 according to claim 2, characterized in that: The preparation method of the iron-doped silica comprises the following steps: placing silica into a stainless steel ball milling jar, adding stainless steel ball milling beads and anhydrous ethanol, placing the silica into a planetary jar ball mill, and washing and drying the resulting jar after ball milling to obtain the iron-doped silica.
4. The green method for preparing water gas by using silicon dioxide piezoelectric catalysis to reduce CO2 according to claim 3, characterized in that: The mass of the silicon dioxide in the stainless steel ball milling jar is 1 to 5 g, the diameter of the stainless steel ball milling beads is 5 mm, the number of the stainless steel ball milling beads is 20 to 50, and the volume of the anhydrous ethanol is 10 to 50 mL.
5. The green method for preparing water gas by using silicon dioxide piezoelectric catalysis to reduce CO2 according to claim 1, characterized in that: The CO2 gas introduction pressure is 1 bar to 10 bar.
6. The green method for preparing water gas by using silicon dioxide piezoelectric catalysis to reduce CO2 according to claim 1, characterized in that: The mass ratio of the silicon dioxide piezoelectric catalyst to ultrapure water is 1:1-1:
50.
7. The green method for preparing water gas by using silicon dioxide piezoelectric catalysis to reduce CO2 according to claim 1, characterized in that: The mechanical force is applied in the form of ultrasound, ball milling or stirring.
8. A reactor for the green water gas production method using silicon dioxide piezoelectric catalytic CO2 reduction according to any one of claims 1 to 7, characterized in that: The reactor is an ultrasonic piezoelectric catalytic reactor, a ball milling piezoelectric catalytic reactor or a stirring piezoelectric catalytic reactor. The reaction chamber of the ultrasonic piezoelectric catalytic reactor adopts an integrally closed structure and is equipped with a pressure monitoring valve. The top cover is provided with two gas valves, which are respectively used for the input of CO2 gas and the output of water gas. A hole is also reserved for installing an ultrasonic rod to realize ultrasonic action.
9. The reactor for the green water gas production method using silicon dioxide piezoelectric catalytic CO2 reduction according to claim 8, characterized in that: The reaction chamber of the ball milling piezoelectric catalytic reactor adopts an integrally sealed structure and is equipped with a pressure monitoring valve. The top cover is provided with two gas valves, one for inputting CO2 gas and the other for outputting water gas. Ball milling beads are placed inside the chamber, and the ball milling process is achieved by placing the drum-type chamber horizontally and rotating it.
10. The reactor for the green water gas production method using silicon dioxide piezoelectric catalytic CO2 reduction according to claim 8, characterized in that: The reaction chamber of the stirred piezoelectric catalytic reactor adopts an integrally closed structure and is equipped with a pressure monitoring valve. The top cover is provided with two gas valves for inputting CO2 gas and outputting water gas respectively. Blades and a motor are installed at the bottom of the reaction chamber to control the rotation of the blades and perform stirring.