C1 gas green conversion method

Abstract

The invention relates to the technical field of green energy, and particularly discloses a C1 gas green conversion method which comprises the following steps: firstly, water and a modifier are mixed to obtain a raw material solution, and the modifier is selected from one or more of a nano material with dielectric property, a conductive polymer and inorganic salt with oxidation-reduction property; secondly, mixed gas containing the C1 gas and the raw material liquid are input into a micro-droplet generation device, the raw material liquid generates micro-droplets under the action of atomized gas containing the C1 gas, the size of the micro-droplets is smaller than or equal to 10 micrometers, the micro-droplets have a strong electric field, water is induced to be homogenized, and hydrogen free radicals (. H) and hydroxyl free radicals (. OH) are generated; the hydrogen radical (. H) and the hydroxyl radical (. OH) are both reacted with a C1 gas comprising one or more of CH4, CO2, and CO to produce a C1 converted product. According to the method disclosed by the invention, the C1 gas is promoted to be continuously converted with (. H) and (. OH) by virtue of a confinement effect of a micro-droplet gas-liquid interface, and a C1 conversion product is continuously generated, so that the method is low in energy consumption, simple in step, high in equilibrium conversion rate and more in selectivity.

Description

Technical Field

[0001] The present invention relates to the technical field of green energy, and in particular to a C1 gas green conversion method. Background Art

[0002] Carbon-one chemistry is an organic chemistry and process that uses compounds containing one carbon atom (such as CH4, CO, CO2) as raw materials to synthesize chemical products or liquid fuels. Carbon-one chemistry can convert carbon-one gas molecules (CH4, CO2, CO) into high-value chemicals. It plays an important role in the conversion and utilization of non-petroleum carbon resources such as natural gas, coal, biomass and CO2, and is a hot topic in chemical research in recent years. The gradual consumption of global fossil resources has brought increasingly severe environmental pollution problems. It is particularly important to seek low-carbon emission and efficient ways to convert C1 molecules (carbon-one molecules) into fuels or high-value-added chemicals. However, due to the large differences in the chemical properties of C1 molecules, such as relatively inert gases such as CH4 and CO2; relatively active gases such as CO, there are certain limitations in terms of equilibrium conversion rate and selectivity. At present, the industrial conversion of carbon-one molecules usually has problems such as high energy consumption, many steps, and complex product separation processes.

[0003] Based on this, it is urgently necessary for technical personnel in this field to provide a green conversion method for C1 gas with low energy consumption, simple steps, simple product separation process, high equilibrium conversion rate and more selectivity. Summary of the invention

[0004] The object of the present invention is to provide a C1 gas green conversion method to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a C1 gas green conversion method, comprising the following steps:

[0006] S1: mixing water and a modifier to obtain a raw material solution; the modifier is one or more of a nanomaterial with dielectric properties, a conductive polymer, and an inorganic salt with redox properties;

[0007] S2: The mixed gas containing C1 gas and the raw material liquid in S1 are input into a micro-droplet generating device, and the raw material liquid generates micro-droplets under the action of the atomizing gas containing C1 gas, wherein the size of the micro-droplets is less than or equal to 10 microns, and the generated micro-droplets have a strong electric field, and the micro-droplets with a strong electric field can induce water to undergo homolysis, generating hydrogen free radicals (·H) and hydroxyl free radicals (·OH);

[0008] S3: The hydrogen radicals (·H) and hydroxyl radicals (·OH) generated at the gas-liquid interface of the microdroplets react with the C1 gas to generate C1 conversion products.

[0009] The reaction equation of the C1 gas is as follows:

[0010]

[0011] Furthermore, in step S1, the inorganic salt includes one or more of chloroauric acid, palladium chloride and chloroauric acid-palladium chloride; the nanomaterial includes one or more of gold nanoparticles (AuNPs), palladium-coated gold nanoparticles (Au@PdNPs), gold-palladium alloy nanoparticles (AuPdalloy) and magnetic nanoparticles; the conductive polymer includes C 60 -(OH)n, one or more of alkalized polyaniline-gold nanoparticle complex and acidified polyaniline-gold nanoparticle complex.

[0012] Furthermore, the concentration of the inorganic salt in the raw material solution is 1-1000 μg / mL; the concentration of the nanomaterial in the raw material solution is 1-800 μg / mL; and the concentration of the conductive polymer in the raw material solution is 1-1000 μg / mL.

[0013] Furthermore, the micro-droplet generating device in S2 includes a pneumatic spray device or an electrospray device, and the pneumatic spray device or the electrospray device is equipped with one or more spray probes.

[0014] Furthermore, the pneumatic spray device is placed in an oil bath heating device, the oil bath temperature of the oil bath heating device is 50-80°C; the electrospray device is provided with a set of high voltages with opposite polarities, the high voltage is 0.5-10kV, and the electrospray device is provided with a rotating electrode, the rotating electrode rotation speed is 1000-10000rpm.

[0015] Furthermore, the spray probe is composed of a sheath gas pipeline and a liquid pipeline. The raw liquid is transported to the micro-droplet device by the liquid pipeline, and the mixed gas containing Cl gas is transported to the micro-droplet device by the sheath gas pipeline, so as to form an inert atmosphere of Cl gas containing micro-droplets. The Cl gas atmosphere containing micro-droplets helps to form a gas-liquid interface confined reaction.

[0016] Furthermore, in step S2, the flow rate of the raw material liquid injected into the liquid pipeline is 5-150 μL / min, and the pressure of the mixed gas input into the sheath gas pipeline is 60-150 psi.

[0017] Furthermore, the mixed gas in S3 includes C1 gas and inert gas, the C1 gas includes one or more of CH4, CO2 and CO, and the inert gas is argon.

[0018] Furthermore, the volume fraction of the C1 gas is 5-40%, and the volume fraction of the inert gas is 60-95%.

[0019] Furthermore, the C1 conversion product in step S3 includes methanol, formaldehyde and formic acid or others.

[0020] Compared with the prior art, the beneficial effects of the present invention are: the green conversion method of C1 gas has low energy consumption, simple steps, simple product separation process, high equilibrium conversion rate of C1 gas and more selectivity. The details are as follows:

[0021] (1) The present invention utilizes a micro-droplet generating device to obtain micro-droplets with a diameter less than or equal to 10 μm. The micro-droplets serve as micro-reactors. Based on the gas-liquid interface effect and the strong electric field effect of the gas-liquid interface, the micro-droplets can spontaneously induce water to undergo a homolytic splitting reaction to generate hydrogen free radicals (·H) with a strong reducing effect and hydroxyl free radicals (·OH) with a strong oxidizing effect. The reduction and oxidation of Cl gas can be achieved at the gas-liquid interface of the micro-droplets. Specifically, the reduction of CO2 and CO and the oxidation of CH4 can be achieved at the gas-liquid interface of the micro-droplets. The method of the present invention has low energy consumption and simple steps.

[0022] (2) The method of the present invention can adjust the thickness of the double electric layer by adding a modifier, effectively stripping the electrons of the generated hydrogen free radicals (·H) and the hydroxyl free radicals (·OH) with strong oxidizing effect, and promoting the distribution of hydrogen free radicals and hydroxyl free radicals on both sides of the double electric layer and accumulating them. The mixed gas containing C1 gas directly contacts the double electric layer of the gas-liquid interface of the micro-droplet, and the highly reactive hydrogen free radicals (·H) and hydroxyl free radicals (·OH) both participate in the reaction with the C1 gas, thereby improving the equilibrium conversion rate of the C1 gas reaction; due to the continuous consumption of hydrogen free radicals (·H) and hydroxyl free radicals (·OH), under the stripping electron effect of the modifier with dielectric properties, more hydrogen free radicals (·H) and hydroxyl free radicals (·OH) are spontaneously generated and participate in the reduction and oxidation reactions of the C1 gas, and finally generate C1 conversion products containing methanol (CH3OH), formaldehyde (HCHO), formic acid (HCOOH) or other products; so that the C1 gas can be continuously converted, and the conversion selectivity is more.

[0023] (3) The green conversion method of C1 gas simultaneously utilizes the reduction characteristics of hydrogen radicals (·H) and the oxidation characteristics of hydroxyl radicals (·OH) to achieve the reduction of CO2 and CO and the oxidation of CH4 at the micro-droplet gas-liquid interface. Compared with the single use of hydrogen radicals (·H) for reduction reaction or the single use of hydroxyl radicals (·OH) for oxidation reaction, the method of the present application simultaneously introduces three C1 gases. These three C1 gases are self-consistent in the closed loop of the redox process, produce good synergistic effects, and promote the improvement of conversion rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present disclosure and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 This is a process diagram of the reaction between C1 gas and micro-droplets to generate C1 conversion products in the embodiment;

[0026] Figure 2 This is a schematic diagram of the structure of a micro-droplet reaction detection device in an embodiment;

[0027] Figure 3 It is a schematic diagram of the structure of the micro-droplet generating device in the embodiment;

[0028] Figure 4 is a mass spectrum of the microdroplet reaction in the embodiment;

[0029] Figure 5 is a mass spectrum of the microdroplet reaction in the embodiment;

[0030] Figure 6 It is the mass spectrum of the micro-droplet reaction in the example.

[0031] Figure numerals: 1 is a liquid pipeline; 2 is a sheath gas pipeline; 3 is a collecting chamber; 4 is a collecting device; 5 is an oil bath heating device; 6 is a delivery pipeline; 7 is a mass spectrometer; 8 is an air outlet pipeline; 9 is a rotating electrode; and 10 is a liquid outlet pipeline. DETAILED DESCRIPTION

[0032] The technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, rather than all the embodiments. The accompanying drawings of the present embodiment are only used as schematic illustrations and are not intended to limit the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention. If the specific conditions are not indicated in the present embodiment, proceed according to the normal conditions or the conditions recommended by the manufacturer. If the manufacturer is not indicated in the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0033] This embodiment adopts Figure 2 and Figure 3 The device shown performs green conversion reaction of C1 gas. Figure 2 and Figure 3 The connection parts in the device shown are all sealed connections. Figure 2It is a structural schematic diagram of a pneumatic spray reaction detection device, which is equipped with a spray probe. In other embodiments, two or more spray probes may be provided. The spray probe includes a liquid pipeline 1 and a sheath gas pipeline 2. The raw liquid is injected from the liquid pipeline 1, and the C1 gas and the inert gas are introduced from the sheath gas pipeline 2. The end of the liquid pipeline 1 extends into the collecting chamber 3 of the collecting device 4. The collecting device 4 is placed in an oil bath heating device 5. The generated C1 conversion product is kept in a gaseous state by the oil bath heating device 5, and then enters the mass spectrometer 7 through a delivery pipeline 6 connected to the collecting chamber 3 for product analysis.

[0034] Figure 3 It is a schematic diagram of the collection structure of the electrospray device, which is equipped with a spray probe. In other embodiments, two or more spray probes can be configured. The spray probe includes a liquid pipeline 1 and a sheath gas pipeline 2. The raw material liquid is injected from the liquid pipeline 1, and the C1 gas and the inert gas are introduced into the collection chamber 3 from the sheath gas pipeline 2. The liquid pipeline 1 extends into the collection chamber 3. A rotating electrode 9 is provided at the inner bottom of the collection chamber 3. A negative high voltage is applied to the liquid pipeline 1 of the spray probe, and a positive high voltage is applied to the rotating electrode 9. The high voltage is any value between 0.5 and 10 kV. The high voltages on the liquid pipeline 1 and the rotating electrode 9 are only opposite in polarity. A gas outlet pipeline 8 is connected to one side of the collection chamber 3 for discharging gas, and a liquid outlet pipeline 10 is connected below the collection chamber 3 for discharging liquid containing C1 conversion products.

[0035] Embodiment 1:

[0036] A C1 gas green conversion method in this embodiment adopts Figure 2 The pneumatic spray reaction detection device shown performs micro-droplet reaction and online mass spectrometry detection, specifically comprising the following steps:

[0037] S1: Mix water and gold-palladium alloy nanoparticles as a modifier to obtain a raw material solution, so that the concentration of gold-palladium alloy nanoparticles in the raw material solution is 1 μg / mL; in other embodiments, the modifier can also be chloroauric acid, palladium chloride, chloroauric acid-palladium chloride, gold nanoparticles (AuNPs), palladium-coated gold nanoparticles (Au@Pd NPs), gold-palladium alloy nanoparticles (AuPd alloy), magnetic nanoparticles, C 60-(OH)n, one or more of alkalized polyaniline-gold nanoparticle complexes and acidified polyaniline-gold nanoparticle complexes; the concentration of the inorganic salt in the raw material solution can be any value in the range of 1-1000 μg / mL; the concentration of the nanomaterial in the raw material solution is any value in the range of 1-800 μg / mL; the concentration of the conductive polymer in the raw material solution is any value in the range of 1-1000 μg / mL, preferably the concentration of the inorganic salt in the raw material solution is 5-50 μg / mL; the concentration of the nanomaterial in the raw material solution is 50-300 μg / mL; the concentration of the conductive polymer in the raw material solution is 40-400 μg / mL;

[0038] S2: A mixed gas of 5% by volume of methane (CH4) and 95% by volume of argon (Ar) and the raw material liquid in S1 are input into a micro-droplet generating device, and the raw material liquid generates micro-droplets under the action of the C1 gas atomizing gas of the mixed gas of 5% by volume of methane (CH4) and 95% by volume of argon (Ar), and the size of the generated micro-droplets of the raw material liquid is controlled to be less than or equal to 10 μm, and the generated micro-droplets have a strong electric field, and the micro-droplets with a strong electric field can induce water to undergo homolysis to generate hydrogen free radicals (·H) and hydroxyl free radicals (· OH), the pressure of the mixed gas input into the micro-droplet generating device from the sheath gas pipeline is 60psi, the flow rate of the raw material liquid injected from the liquid pipeline into the collecting chamber of the pneumatic spray device is 5μL / min, the oil bath temperature is 50°C, and the flight speed of the micro-droplets is 84m / s; in other specific embodiments, the pressure of the mixed gas input into the micro-droplet generating device can be any value in the range of 60-150psi, the flow rate of the raw material liquid injected from the liquid pipeline into the collecting chamber of the pneumatic spray device can be any value in the range of 5-150μL / min, and the oil bath temperature is any value in the range of 50-80°C;

[0039] S3: The hydrogen radicals (·H) and hydroxyl radicals (·OH) generated at the gas-liquid interface of the microdroplets react with the C1 gas CH4 to generate C1 conversion products. The C1 conversion products are detected by mass spectrometry. The results show that the C1 conversion products include formic acid (HCOOH), methanol (CH3OH) and formaldehyde (HCHO) and other substances.

[0040] The C1 conversion product includes one or more of formic acid (HCOOH), methanol (CH3OH) and formaldehyde (HCHO), and the reaction product enters the mass spectrometer for detection.

[0041] The reaction equation of C1 gas in this embodiment is as follows:

[0042]

[0043] Embodiment 2:

[0044] A C1 gas green conversion method in this embodiment adopts Figure 2 The pneumatic spray reaction detection device shown performs micro-droplet reaction and online mass spectrometry detection, specifically comprising the following steps:

[0045] S1: water and the modifier palladium-coated gold nanoparticles are mixed to obtain a raw material solution, and the concentration of the palladium-coated gold nanoparticles in the raw material solution is 175 μg / mL; in other embodiments, the modifier can also be chloroauric acid, palladium chloride, chloroauric acid-palladium chloride, gold nanoparticles (AuNPs), palladium-coated gold nanoparticles (Au@Pd NPs), gold-palladium alloy nanoparticles (AuPdalloy), magnetic nanoparticles, C 60 -(OH)n, one or more of alkalized polyaniline-gold nanoparticle complexes and acidified polyaniline-gold nanoparticle complexes; the concentration of the inorganic salt in the raw material solution can be any value in the range of 1-1000 μg / mL; the concentration of the nanomaterial in the raw material solution is any value in the range of 1-800 μg / mL; the concentration of the conductive polymer in the raw material solution is any value in the range of 1-1000 μg / mL, preferably the concentration of the inorganic salt in the raw material solution is 5-50 μg / mL; the concentration of the nanomaterial in the raw material solution is 50-300 μg / mL; the concentration of the conductive polymer in the raw material solution is 40-400 μg / mL;

[0046] S2: A mixed gas of 5% by volume carbon dioxide (CO2) and 95% by volume argon (Ar) and the raw material liquid in S1 are input into a micro-droplet generating device, and the raw material liquid generates micro-droplets under the action of C1 gas atomizing gas of the mixed gas of 5% by volume carbon dioxide (CO2) and 95% by volume argon (Ar), and the raw material liquid is controlled to generate micro-droplets with a size less than or equal to 10 μm, and the generated micro-droplets have a strong electric field, and the micro-droplets with a strong electric field can induce water to undergo homolysis to generate hydrogen free radicals (·H) and hydroxyl free radicals (·OH), the pressure of the mixed gas input into the micro-droplet generating device from the sheath gas pipeline is 100psi, the flow rate of the raw material liquid injected from the liquid pipeline into the collecting chamber of the pneumatic spray device is 80μL / min, the oil bath temperature is 60°C, and the flight speed of the micro-droplets is 96m / s; in other specific embodiments, the pressure of the mixed gas input into the micro-droplet generating device can be any value in the range of 60-150psi, the flow rate of the raw material liquid injected from the liquid pipeline into the collecting chamber of the pneumatic spray device can be any value in the range of 5-150μL / min, and the oil bath temperature is any value in the range of 50-80°C;

[0047] S3: The hydrogen radicals (·H) and hydroxyl radicals (·OH) generated at the gas-liquid interface of the microdroplets react with the C1 gas CO2 to generate C1 conversion products. The C1 conversion products enter the mass spectrometer for detection. The results show that the C1 conversion products include formic acid (HCOOH), methanol (CH3OH) and formaldehyde (HCHO) and other substances.

[0048] The reaction equation of C1 gas in this embodiment is as follows:

[0049]

[0050] Embodiment 3:

[0051] A C1 gas green conversion method in this embodiment adopts Figure 2 The pneumatic spray reaction detection device shown performs micro-droplet reaction and online mass spectrometry detection, specifically comprising the following steps:

[0052] S1: Mix water and gold nanoparticles as a modifier to obtain a raw material solution, wherein the concentration of gold nanoparticles in the raw material solution is 800 μg / mL; in other embodiments, the modifier may also be chloroauric acid, palladium chloride, chloroauric acid-palladium chloride, gold nanoparticles (AuNPs), palladium-coated gold nanoparticles (Au@PdNPs), gold-palladium alloy nanoparticles (AuPdalloy), magnetic nanoparticles, C 60 -(OH)n, one or more of alkalized polyaniline-gold nanoparticle complexes and acidified polyaniline-gold nanoparticle complexes; the concentration of the inorganic salt in the raw material solution can be any value in the range of 1-1000 μg / mL; the concentration of the nanomaterial in the raw material solution is any value in the range of 1-800 μg / mL; the concentration of the conductive polymer in the raw material solution is any value in the range of 1-1000 μg / mL, preferably the concentration of the inorganic salt in the raw material solution is 5-50 μg / mL; the concentration of the nanomaterial in the raw material solution is 50-300 μg / mL; the concentration of the conductive polymer in the raw material solution is 40-400 μg / mL;

[0053] S2: A mixed gas of 5% by volume carbon monoxide (CO) and 95% by volume argon (Ar) and the raw material liquid in S1 are input into a micro-droplet generating device, and the raw material liquid generates micro-droplets under the action of the C1 gas atomizing gas of the mixed gas of 5% by volume carbon monoxide (CO) and 95% by volume argon (Ar), and the raw material liquid is controlled to generate micro-droplets with a size less than or equal to 10 μm, and the generated micro-droplets have a strong electric field, and the micro-droplets with a strong electric field can induce water to undergo homolysis to generate hydrogen free radicals (·H) and hydroxyl free radicals (·H). OH), the pressure of the mixed gas input into the micro-droplet generating device from the sheath gas pipeline is 150psi, the flow rate of the raw material liquid injected from the liquid pipeline into the collecting chamber of the pneumatic spray device is 150μL / min, the oil bath temperature is 80°C, and the flight speed of the micro-droplets is 105m / s; in other specific embodiments, the pressure of the mixed gas input into the micro-droplet generating device can be any value in the range of 60-150psi, the flow rate of the raw material liquid injected from the liquid pipeline into the collecting chamber of the pneumatic spray device can be any value in the range of 5-150μL / min, and the oil bath temperature is any value in the range of 50-80°C;

[0054] S3: The hydrogen radicals (·H) and hydroxyl radicals (·OH) generated at the gas-liquid interface of the microdroplets react with the C1 gas CO to generate C1 conversion products. The C1 conversion products are detected by mass spectrometry. The results show that the C1 conversion products include formic acid (HCOOH), methanol (CH3OH) and formaldehyde (HCHO) and other substances.

[0055] The reaction equation of C1 gas is as follows:

[0056]

[0057] Embodiment 4:

[0058] A C1 gas green conversion method in this embodiment adopts Figure 3 The micro-droplet device-electrospray device is used to react, and the C1 compound generated by the reaction of the C1 gas and the micro-droplets is collected and detected, which specifically includes the following steps:

[0059] S1: Mix water with the modifiers chloroauric acid, chloroauric acid-palladium chloride, and C 60-(OH)n are mixed to prepare raw material solutions a, b and c with concentrations of 1, 500 and 1000 μg / mL respectively, and water and modifier magnetic nanoparticles ferroferric oxide and alkalized polyaniline-gold nanoparticle complex are mixed to prepare raw material solution d with a concentration of 200 μg / mL, wherein the concentration of magnetic nanoparticles ferroferric oxide is 80 μg / mL, and the concentration of alkalized polyaniline-gold nanoparticle complex is 120 μg / mL; in other embodiments, the modifier can also be chloroauric acid, palladium chloride, chloroauric acid-palladium chloride, gold nanoparticles, palladium-coated gold nanoparticles, gold-palladium alloy nanoparticles, magnetic nanoparticles, C 60 -(OH)n, one or more of alkalized polyaniline-gold nanoparticle complexes and acidified polyaniline-gold nanoparticle complexes; the concentration of the inorganic salt in the raw material solution can be any value in the range of 1-1000 μg / mL; the concentration of the nanomaterial in the raw material solution is any value in the range of 1-800 μg / mL; the concentration of the conductive polymer in the raw material solution is any value in the range of 1-1000 μg / mL, preferably the concentration of the inorganic salt in the raw material solution is 5-50 μg / mL; the concentration of the nanomaterial in the raw material solution is 50-300 μg / mL; the concentration of the conductive polymer in the raw material solution is 40-400 μg / mL;

[0060] S2: The raw material liquid a described in S1 is introduced into the electrospray device from the liquid pipeline, and the liquid pipeline 1 and the sheath gas pipeline 2 form a double-layer sleeve, and the end of the double-layer sleeve extends into the collection chamber 3; the raw material liquid is introduced into the sheath gas pipeline 2 of the micro-droplet generating device by introducing a mixed gas of C1 gas of a certain volume ratio of CO2, CH4 and CO (the specific ratio of the mixed gas is referred to Table 1) and a certain volume fraction of argon (Ar) into the micro-droplet generating device, and micro-droplets are generated under the action of the atomizing gas. The spray end of the spray probe is applied with a bias voltage of -0.5 kV, the rotating electrode 9 is applied with a bias voltage of +0.5 kV, and the rotating speed of the rotating electrode 9 is 1000 rpm, the raw material liquid generates microdroplets with a size less than or equal to 10 μm, the generated microdroplets have a strong electric field, and the microdroplets with a strong electric field can induce water to undergo homolysis to generate hydrogen radicals (·H) and hydroxyl radicals (·OH), and the flight speed of the microdroplets is 94 m / s; in other specific embodiments, the pressure of the mixed gas input to the microdroplet generating device can be any value in the range of 60-150 psi; the raw material liquid input flow rate is any value in the range of 5-150 μL / min, the applied bias voltage is any value in the range of 0.5-10 kV, and the rotating electrode speed is any value in the range of 1000-10000 rpm.

[0061] S3: Hydrogen radicals (·H) and hydroxyl radicals (·OH) generated at the gas-liquid interface of the microdroplets react with the C1 gas. After 60 minutes of electrospraying, the collected solution is detected by headspace-gas chromatography.

[0062] The raw material liquids b, c and d were subjected to the experiment according to the above steps S2 and S3, wherein in step S2, the injection flow rate of the raw material liquid b was 5 μL / min, the injection flow rate of the raw material liquid c was 100 μL / min, and the injection flow rate of the raw material liquid d was 150 μL / min; the spray probe containing the raw material liquid b was applied with a bias voltage of -3.5 kV, the rotating electrode 9 was applied with a bias voltage of +3.5 kV, and the rotation speed of the rotating electrode 9 was 4500 rpm; the spray probe containing the raw material liquid c was applied with a bias voltage of -7 kV, and the rotating electrode 9 was applied with a bias voltage of +7 k V, the rotation speed of the rotating electrode 9 is 7500rpm, the spray probe containing the raw material liquid d is applied with a bias voltage of -10kV, the bias voltage applied to the rotating electrode 9 is +10kV, and the rotation speed of the rotating electrode 9 is 10000rpm; the pressure of the mixed gas input into the micro-droplet generating device containing the raw material liquid b is 60psi, the pressure of the mixed gas input into the micro-droplet generating device containing the raw material liquid c is 100psi, and the pressure of the mixed gas input into the micro-droplet generating device containing the raw material liquid d is 150psi. For specific compositions and products, see Table 1 below.

[0063] The reaction equation of C1 gas is as follows:

[0064]

[0065] Table 1 Conversion rate of C1 gas in different raw liquids and mixed gases

[0066]

[0067]

[0068] It can be seen from the detection results of this embodiment that the micro-droplets, as micro-reactors, can promote the reduction of CO2 and CO and the oxidation of CH4 by Cl gas at the gas-liquid interface of the micro-droplets. The method of this embodiment can adjust the thickness of the double electric layer by adding a modifier, effectively stripping the electrons of the generated hydrogen radicals (·H) and the strongly oxidizing hydroxyl radicals (·OH), promoting the distribution of hydrogen radicals and hydroxyl radicals on both sides of the double electric layer and accumulating them. The mixed gas containing C1 gas directly contacts the double electric layer of the gas-liquid interface of the micro-droplet, and the highly reactive hydrogen radicals (·H) and hydroxyl radicals (·OH) participate in the reaction with the C1 gas, thereby improving the equilibrium conversion rate of the C1 gas reaction; due to the continuous consumption of hydrogen radicals (·H) and hydroxyl radicals (·OH), under the action of the stripping electron effect of the modifier with dielectric properties, more hydrogen radicals (·H) and hydroxyl radicals (·OH) are spontaneously generated, and participate in the reduction and oxidation reactions of the C1 gas, and finally generate C1 conversion products containing methanol (CH3OH), formaldehyde (HCHO), formic acid (HCOOH) or other products; the C1 gas can be continuously converted, and the C1 gas conversion selectivity is more.

[0069] Comparative Example 1:

[0070] A C1 gas green conversion method in this comparative example adopts Figure 2 The pneumatic spray reaction detection device shown performs micro-droplet reaction and online mass spectrometry detection, including the following steps:

[0071] S1: injecting pure water as raw material liquid into the micro-droplet generation device;

[0072] S2: A mixed gas of 5% by volume of methane (CH4) and 95% by volume of argon (Ar) is input into the micro-droplet generation device from the sheath gas pipeline. The pressure of the mixed gas input into the micro-droplet generation device is 60 psi. The flow rate of the raw material liquid injected from the liquid pipeline into the collection chamber of the pneumatic spray device is 5 μL / min. The oil bath temperature is 50°C.

[0073] S3: Online mass spectrometry detection of C1 gas CH4 reaction to detect C1 reaction products.

[0074] The raw material liquid and the product in Example 1 and Comparative Example 1 were tested. Figure 4 , attached Figure 4 is the mass spectrum of the raw material liquid and pure water obtained under CH4-Ar gas atmosphere, in which Figure 4 The upper part is the mass spectrum of pure water, and the lower part is the mass spectrum of the raw material solution in Example 1. Figure 4 It can be seen that after in-situ and real-time detection of online mass spectrometry, in the mass spectrum, the mass peaks of m / z 16, 30, 32 and 46 are methane (CH4), formaldehyde (HCHO), methanol (CH3OH) and formic acid (HCOOH), respectively. Under the condition of micro-droplet reaction in pure water, methanol (CH3OH), formaldehyde (HCHO) and formic acid (HCOOH) are almost not generated. In the mass spectrum of the micro-droplet reaction of the raw material solution containing 1μg / mL AuPd alloyNPs in Example 1, the relative abundance of the mass peaks of m / z 32, 30 and 46 is significantly enhanced, which are 68%, 21% and 20%, respectively. This result shows that the micro-droplet reaction of the raw material solution containing 1μg / mL AuPd alloyNPs can significantly regulate the amount of methanol (CH3OH), formaldehyde (HCHO) and formic acid (HCOOH) generated by methane (CH4) in the micro-droplet reaction. Since there is no continuous contact between methane (CH4) and individual microdroplets, the induced reaction has discontinuous characteristics. In view of this, in the limited flight distance of the microdroplet reaction, combined with the flight speed of the microdroplet, methane (CH4) and the AuPd alloy NPs microdroplets containing 1μg / mL will undergo an oxidation reaction mediated by hydroxyl radicals (·OH) at the gas-liquid interface, accompanied by the production of different C1 chemical products.

[0075] Comparative Example 2

[0076] A C1 gas green conversion method in this comparative example adopts Figure 2 The pneumatic spray reaction detection device shown performs micro-droplet reaction and online mass spectrometry detection, including the following steps:

[0077] S1: injecting pure water as raw material liquid into the micro-droplet generation device;

[0078] S2: A mixed gas of 5% by volume carbon dioxide (CO2) and 95% by volume argon (Ar) is input into the micro-droplet generating device from the sheath gas pipeline. The pressure of the mixed gas input into the micro-droplet generating device is 100 psi. The flow rate of the raw material liquid injected from the liquid pipeline into the collecting chamber of the pneumatic spray device is 80 μL / min. The oil bath temperature is 60°C.

[0079] S3: Online mass spectrometry detection of C1 gas CO2 reaction to detect C1 reaction products.

[0080] The raw material liquid and the product in Example 2 and Comparative Example 2 were tested. Figure 5 , attached Figure 5 The mass spectra of the raw material liquid and pure water obtained under CO2-Ar atmosphere, Figure 5 The upper part is the mass spectrum of pure water, and the lower part is the mass spectrum of the raw material solution in Example 2. Figure 5It can be seen that after in-situ and real-time detection of online mass spectrometry, in the mass spectrum, the mass peaks of m / z 44, 30, 32 and 46 are carbon dioxide (CO2), formaldehyde (HCHO), methanol (CH3OH) and formic acid (HCOOH), respectively. Under pure water conditions, the relative abundance of carbon dioxide is 100%, while the relative abundances of methanol, formaldehyde and formic acid are all less than 1%. This result shows that under pure water conditions, methanol (CH3OH), formaldehyde (HCHO) and formic acid (HCOOH) are almost not generated. In the mass spectrum of the micro-droplet reaction containing 175μg / mL raw material solution, the relative abundance of the mass peaks of m / z 32, 30 and 46 is significantly enhanced, which are 61%, 19% and 49% respectively. The results show that the microdroplet reaction of the raw material solution containing 175μg / mL AuPdalloyNPs can significantly regulate the amount of methanol (CH3OH), formaldehyde (HCHO) and formic acid (HCOO) generated by carbon dioxide (CO2) in the microdroplet reaction. Since carbon dioxide (CO2) has discontinuous contact with individual microdroplets, the induced reaction has discontinuous characteristics. In view of this, in the limited flight distance of the microdroplet reaction, combined with the flight speed of the microdroplet, carbon dioxide (CO2) and the microdroplets containing 175μg / mL AuPd alloy NPs will undergo a reduction reaction mediated by hydrogen free radicals (·H) at the gas-liquid interface, first generating formic acid (HCOOH), and then further reducing to generate different C1 conversion products such as formaldehyde (HCHO) and methanol (CH3OH).

[0081] Comparative Example 3

[0082] A C1 gas green conversion method in this comparative example adopts Figure 2 The pneumatic spray reaction detection device shown performs micro-droplet reaction and online mass spectrometry detection, including the following steps:

[0083] S1: injecting pure water as raw material liquid into the micro-droplet generation device;

[0084] S2: A mixed gas of 5% by volume carbon monoxide (CO) and 95% by volume argon (Ar) is input into the micro-droplet generation device from the sheath gas pipeline. The pressure of the mixed gas input into the micro-droplet generation device is 150 psi. The flow rate of the raw material liquid injected from the liquid pipeline into the collection chamber of the pneumatic spray device is 150 μL / min. The oil bath temperature is 80°C.

[0085] S3: Online mass spectrometry detection of C1 gas CO reaction to detect C1 reaction products.

[0086] The raw material liquid and the product in Example 3 and Comparative Example 3 were tested. Figure 6 , attached Figure 6is the mass spectrum of the raw material liquid and pure water obtained under CO-Ar gas atmosphere, Figure 6 The upper part is the mass spectrum of pure water, and the lower part is the mass spectrum of the raw material solution in Example 3. Figure 6 It can be seen that after in-situ and real-time detection of online mass spectrometry, in the mass spectrum, the mass peaks of m / z 18, 28, 30, 32 and 46 are water (H2O), carbon monoxide (CO), formaldehyde (HCHO), methanol (CH3OH) and formic acid (HCOOH), respectively. Under pure water conditions, the relative abundance of carbon monoxide is 100%, while the relative abundance of water is 8%, while the relative abundances of methanol, formaldehyde and formic acid are all less than 2%. This result shows that methanol, formaldehyde and formic acid are almost not generated under the conditions of pure water solution microdroplets. In the mass spectrum of the microdroplet reaction containing 800μg / mL AuNPs raw material solution, the relative abundance of mass peaks of m / z 32, 30 and 46 is significantly enhanced, which are 46%, 58% and 23%, respectively. The results show that the reaction of the Au NPs aqueous solution containing 800 μg / mL can significantly regulate the amount of methanol (CH3OH), formaldehyde (HCHO) and formic acid (HCOOH) generated by carbon monoxide (CO) in the microdroplet reaction. Since carbon monoxide (CO) is in discontinuous contact with a single microdroplet, the induced reaction has discontinuous characteristics. In view of this, in the limited flight distance of the microdroplet reaction, combined with the flight speed of the microdroplet, carbon monoxide (CO) and the AuNPs microdroplet containing 800 μg / mL will first undergo a reduction reaction mediated by hydrogen radicals (·H) at the gas-liquid interface to generate formaldehyde (HCHO), followed by further reduction of hydrogen radicals (·H) to generate methanol (CH3OH) and further oxidation of hydroxyl radicals (·OH) to generate formic acid (HCOOH) and other C1 conversion products.

[0087] A green conversion method of C1 gas in this embodiment can obtain different concentrations of C1 chemical substances and other substances by adjusting different C1 gas compositions. The results show that as the concentration of AuPd alloy increases, the concentration of C1 chemical substances tends to increase overall. In the system, the concentration of methane directly affects the concentration of formic acid, while the concentration of carbon dioxide controls the concentration of methanol as a whole. In the composite gas composed of three C1 gases, the main products are methanol, formaldehyde and formic acid. With 1μg / mL AuPd alloy aqueous solution droplet reaction, the methane conversion rate is 87%, the selectivity of conversion to formic acid is 87%, the conversion rate of carbon dioxide is 78%, and the selectivity of conversion to methanol is 91%. The method of this embodiment has strong applicability, is convenient for realizing the conversion of C1 gas from the perspectives of green, environmental protection, and high efficiency, is economical and practical, and can provide a systematic and powerful solution for achieving the "dual carbon" goal.

[0088] This embodiment uses a micro-droplet generation device to carry out the conversion reaction of C1 gas. The micro-droplets are used as microreactors. Due to the "confinement" effect caused by the boundary size, they are endowed with special physical and chemical properties, such as large specific surface area, fast reaction speed, special redox ability, and strong electric field at the gas-liquid interface. The strong electric field at the gas-liquid interface of the micro-droplets can induce spontaneous water homolysis reaction to generate hydrogen free radicals (·H) and hydroxyl free radicals (·OH). The highly active and short-half-life hydrogen free radicals (·H) and hydroxyl free radicals (·OH) generated at the gas-liquid interface trigger a free radical chain reaction, which promotes the reduction of CO2 and CO and the oxidation of CH4 by C1 gas at the gas-liquid interface of the micro-droplets. The method of this embodiment can adjust the thickness of the double electric layer by adding a modifier, effectively stripping the electrons of the generated hydrogen free radicals (·H) and the hydroxyl free radicals (·OH) with strong oxidizing effect, and promoting the distribution of hydrogen free radicals and hydroxyl free radicals on both sides of the double electric layer and accumulation. The mixed gas containing C1 gas directly contacts the double electric layer of the gas-liquid interface of the micro-droplet, and the highly reactive hydrogen radicals (·H) and hydroxyl radicals (·OH) participate in the reaction with the C1 gas, thereby improving the equilibrium conversion rate of the C1 gas reaction; due to the continuous consumption of hydrogen radicals (·H) and hydroxyl radicals (·OH), under the action of the stripping electron effect of the modifier with dielectric properties, more hydrogen radicals (·H) and hydroxyl radicals (·OH) are spontaneously generated, and participate in the reduction and oxidation reactions of the C1 gas, and finally generate C1 conversion products containing methanol (CH3OH), formaldehyde (HCHO), formic acid (HCOOH) or other products; so that the C1 gas can be continuously converted with more conversion selectivity.

[0089] In summary, the green conversion method of C1 gas in this embodiment has low energy consumption, simple steps, high equilibrium conversion rate and more selectivity.

[0090] The embodiments described above are only a part of the embodiments disclosed by the present invention, rather than all the embodiments. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present invention is defined by the attached claims rather than the above description, so it is intended to include all changes within the meaning and scope of the equivalent elements of the claims in the present invention. Any figure mark in the claims should not be regarded as limiting the claims involved.

Claims

1. A C1 gas green conversion method, characterized in that: The steps include: S1: mixing water and a modifier to obtain a raw material solution; the modifier is one or more of a nanomaterial with dielectric properties, a conductive polymer, and an inorganic salt with redox properties; S2: Inputting the mixed gas containing C1 gas and the raw material liquid in S1 into a micro-droplet generating device, the raw material liquid generates micro-droplets under the action of the atomizing gas containing C1 gas, the size of the micro-droplets is less than or equal to 10 microns, and the micro-droplets induce water to undergo homolysis to generate hydrogen free radicals (·H) and hydroxyl free radicals (·OH); S3: The hydrogen radicals (·H) and hydroxyl radicals (·OH) generated at the gas-liquid interface of the microdroplets react with the C1 gas to generate C1 conversion products.

2. A C1 gas green conversion method according to claim 1, characterized in that: In step S1, the inorganic salt includes one or more of chloroauric acid, palladium chloride and chloroauric acid-palladium chloride; the nanomaterial includes one or more of gold nanoparticles, palladium-coated gold nanoparticles, gold-palladium alloy nanoparticles and magnetic nanoparticles; the conductive polymer includes C 60 -(OH)n, one or more of alkalized polyaniline-gold nanoparticle complex and acidified polyaniline-gold nanoparticle complex.

3. A C1 gas green conversion method according to claim 2, characterized in that: The concentration of the inorganic salt in the raw material solution is 1-1000 μg / mL; the concentration of the nano material in the raw material solution is 1-800 μg / mL; and the concentration of the conductive polymer in the raw material solution is 1-1000 μg / mL.

4. A C1 gas green conversion method according to claim 1, characterized in that: The micro-droplet generating device in S2 comprises a pneumatic spray device or an electrospray device, and the pneumatic spray device or the electrospray device is equipped with one or more spray probes.

5. A C1 gas green conversion method according to claim 4, characterized in that: The pneumatic spray device is placed in an oil bath heating device, the oil bath temperature of the oil bath heating device is 50-80°C; the electrospray device is provided with a set of high voltages with opposite polarities, the high voltage is 0.5-10kV, and the electrospray device is provided with a rotating electrode, the rotating speed of the rotating electrode is 1000-10000rpm.

6. A C1 gas green conversion method according to claim 4, characterized in that: The spray probe is composed of a sheath gas pipeline and a liquid pipeline. The raw liquid is transported to the micro-droplet device through the liquid pipeline, and the mixed gas containing Cl gas is transported to the micro-droplet device through the sheath gas pipeline.

7. A C1 gas green conversion method according to claim 6, characterized in that: In step S2, the flow rate of the raw material liquid injected into the liquid pipeline is 5-150 μL / min, and the pressure of the mixed gas input into the sheath gas pipeline is 60-150 psi.

8. A C1 gas green conversion method according to claim 1, characterized in that: The mixed gas in S3 includes C1 gas and inert gas, the C1 gas includes one or more of CH4, CO2 and CO, and the inert gas is argon.

9. A C1 gas green conversion method according to claim 8, characterized in that: The volume fraction of the C1 gas is 5-40%, and the volume fraction of the inert gas is 60-95%.

10. A C1 gas green conversion method according to claim 1, characterized in that: The C1 conversion products in step S3 include methanol, formaldehyde and formic acid.

Images