阅读说明：本技术 气相光反应检测装置及其反应检测方法 (Gas phase photoreaction detection device and photoreaction detection method thereof ) 是由 付毅 陈为 冯光辉 李桂花 宋艳芳 董笑 魏伟 孙予罕 于 2019-01-31 设计创作，主要内容包括：本发明提供一种气相光反应检测装置及其检测方法,该装置包括：水蒸气混合装置,用于将反应气与水蒸气混合,形成混合气；光反应装置,用于将混合气光催化转化；反应产物检测装置,用于在线检测所述光催化转化的产物；水蒸气混合装置、光反应装置及反应产物检测装置依次连通。该装置具有操作简便的优点从整个装置的结构来看,结构设计简单,反应方便,操作简单,易于拆卸；从反应产物的检测来看,整个装置对反应速率和过程都有很好的促进作用,整个反应过程中反应气体以均匀、稳定的流量以及均匀稳定的温度进行反应,从而获得精确的光催化转化作用下催化剂的反应速率,对整个光催化转化反应具有重要意义。(The invention provides a gas phase photoreaction detection device and a detection method thereof, wherein the device comprises: the water vapor mixing device is used for mixing the reaction gas with the water vapor to form mixed gas; the light reaction device is used for carrying out photocatalytic conversion on the mixed gas; a reaction product detection device for detecting the product of the photocatalytic conversion on line; the water vapor mixing device, the light reaction device and the reaction product detection device are communicated in sequence. The device has the advantages of simple and convenient operation, and has simple structural design, convenient reaction, simple operation and easy disassembly from the structural point of view of the whole device; from the detection of reaction products, the whole device has good promotion effect on the reaction rate and the reaction process, and the reaction gas reacts at uniform and stable flow and uniform and stable temperature in the whole reaction process, so that the reaction rate of the catalyst under the action of accurate photocatalytic conversion is obtained, and the device has important significance on the whole photocatalytic conversion reaction.)

1. A gas phase photoreaction detection device, characterized in that, the gas phase photoreaction detection device at least comprises:

the water vapor mixing device is used for mixing the reaction gas with the water vapor to form mixed gas;

the light reaction device is used for carrying out photocatalytic conversion on the mixed gas;

a reaction product detection device for detecting the product of the photocatalytic conversion on line;

the water vapor mixing device, the light reaction device and the reaction product detection device are communicated in sequence.

2. The gas-phase photoreaction detection apparatus according to claim 1, wherein: the gas-phase light reaction detection device also comprises a reaction gas bearing device used for bearing and providing the reaction gas, and the reaction gas bearing device, the water vapor mixing device, the light reaction device and the reaction product detection device are communicated in sequence.

3. The gas-phase photoreaction detection apparatus according to claim 2, wherein: the reaction gas bearing device comprises a reaction gas storage unit, a gas volume flowmeter, a one-way valve and a gas guide pipe, wherein the reaction gas storage unit is communicated with the gas volume flowmeter through the gas guide pipe, the gas volume flowmeter is communicated with the one-way valve through the gas guide pipe, and the one-way valve is communicated with the water vapor mixing device through the gas guide pipe.

4. The gas-phase photoreaction detection apparatus according to claim 1 or 2, wherein: the water vapor mixing device comprises a closed water container, a constant-temperature water tank and a gas guide pipe, wherein the closed water container is provided with an inlet and an outlet, reaction gas passes through the gas guide pipe and passes through the closed water container, the inlet of the closed water container enters the closed water container, the outlet of the closed water container is communicated with the light reaction device through the gas guide pipe, and the closed water container is placed in the constant-temperature water tank.

5. The gas-phase photoreaction detection apparatus according to claim 4, wherein: the light reaction device comprises a reactor, a catalyst placing area, a constant-temperature water tank, a gas guide pipe and a light source, wherein the reactor is provided with an inlet and an outlet, the catalyst placing area is arranged inside the reactor, the light source is arranged above the reactor, the outlet of a sealed water container is communicated with the inlet of the reactor through the gas guide pipe, a reaction gas is subjected to photocatalytic conversion, a product is communicated with the outlet of the reactor through the gas guide pipe and a reaction product detection device, and the reactor is arranged in the constant-temperature water tank.

6. The gas-phase photoreaction detection apparatus according to claim 5, wherein: and a catalyst coating is arranged on part of or all of the surface of the catalyst placing area.

7. The gas-phase photoreaction detection apparatus according to claim 1, wherein: the reaction product detection device comprises a gas chromatograph.

8. A gas phase photoreaction detection method, wherein the methane gas phase photoreaction detection apparatus according to any one of claims 1 to 7 is used, comprising the steps of:

1) introducing reaction gas into the water vapor mixing device, and mixing the reaction gas with water vapor to obtain mixed gas;

2) introducing the mixed gas into the light reaction device, and carrying out catalytic conversion on the mixed gas under the conditions of illumination and a catalyst to obtain a product of catalytic conversion;

3) and introducing the product into the reaction product detection device, and detecting the product.

9. The gas-phase photoreaction detection method according to claim 8, further comprising at least one of the following technical features:

1) in step 1), the reaction gas comprises carbon dioxide or methane;

2) in the step 1), the volume concentration of the reaction gas is between 95.0% and 100%;

3) in the step 1), the flow rate of the reaction gas is between 0.1m L/min and 200m L/min;

4) in the step 1), the temperature of water in the water vapor mixing device is between 10 and 90 ℃;

5) in the step 1), the water is placed in the closed water container, the closed water container is placed in the constant-temperature water tank, and the temperature of the constant-temperature water tank is between 10 ℃ and 90 ℃;

6) in the step 2), the light source for illumination comprises a xenon lamp light source, a sunlight light source or an L ED lamp light source;

7) in the step 2), the illumination time of the illumination is between 10min and 30 h;

8) in the step 2), the catalyst is placed in the catalyst placing area, the catalyst placing area is arranged in the reactor, the reactor is placed in the constant-temperature water tank, and the temperature of the constant-temperature water tank is between 10 ℃ and 90 ℃.

Technical Field

The invention relates to the field of chemical processes and devices, in particular to a gas-phase photoreaction detection device and a gas-phase photoreaction detection method.

Background

At present, the problems of environmental problems, energy shortage and the like are difficult to solve, more and more researches are focused on reasonable and effective utilization of energy, and the great investment on clean energy makes environment-friendly fuels attract much attention, such as natural gas which is one of three fossil fuels and combustible ice which is continuously developed at present. However, methane is a recognized greenhouse gas as a main component of natural gas and combustible ice, and in addition, the problem of methane transportation has not been well solved. Therefore, how to catalytically convert methane into chemicals with high energy density values has become a focus of research. Carbon dioxide is the most important greenhouse gas, and the global warming and ecological problems caused by the carbon dioxide are serious challenges for sustainable development of human beings.

For methane, conventional conversions have a number of disadvantages, such as: harsh reaction conditions (high temperature and high pressure are required), low conversion rate of methane and easy peroxidation of reaction, so that CO in the product is easily oxidized₂Higher ratio, C₂And the selectivity of the product is low. Therefore, people turn their eyes to photocatalytic conversion of methane. In the case of carbon dioxide, in practical application, because carbon dioxide is a typical linear molecule, the chemical structure is extremely stable and difficult to activate, and the conversion and utilization thereof require harsh reaction conditions, the conversion amount of the traditional catalyst is very small. However, the main research focus still lies in the thermal catalysis aspect, and relatively few researches are conducted on the photocatalysis aspect.

Therefore, it is necessary to provide a gas phase photoreaction detection apparatus and a reaction detection method thereof, which are designed with a simple apparatus structure, are convenient to operate, and can realize accurate control of the photocatalytic reaction process, and timely, efficient and accurate detection of reaction products, thereby accurately measuring the performance of the catalyst.

Disclosure of Invention

In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a gas phase photoreaction detection apparatus and a reaction detection method thereof, wherein the gas phase photoreaction detection apparatus has a simple structure design, is convenient to react, is easy to operate and disassemble, and can detect a reaction product timely, efficiently and accurately.

To achieve the above and other related objects, the present invention provides a gas phase photoreaction detection apparatus, which at least comprises:

the water vapor mixing device is used for mixing the reaction gas with the water vapor to form mixed gas;

the light reaction device is used for carrying out photocatalytic conversion on the mixed gas;

a reaction product detection device for detecting the product of the photocatalytic conversion on line;

the water vapor mixing device, the light reaction device and the reaction product detection device are communicated in sequence.

Optionally, the gas-phase photoreaction detection device further comprises a reaction gas carrying device for carrying and providing the reaction gas, and the reaction gas carrying device, the water vapor mixing device, the photoreaction device and the reaction product detection device are sequentially communicated.

Further, the reaction gas bearing device comprises a reaction gas storage unit, a gas volume flowmeter, a one-way valve and a gas conduit, wherein the reaction gas storage unit is communicated with the gas volume flowmeter through the gas conduit, the gas volume flowmeter is communicated with the one-way valve through the gas conduit, and the one-way valve is communicated with the water vapor mixing device through the gas conduit.

Optionally, the water vapor mixing device includes a sealed water container, a constant temperature water tank, and a gas conduit, the sealed water container is provided with an inlet and an outlet, the reaction gas passes through the gas conduit and enters the sealed water container through the inlet of the sealed water container, the outlet of the sealed water container is communicated with the photoreaction device through the gas conduit, and the sealed water container is placed in the constant temperature water tank.

Further, the light reaction device comprises a reactor, a catalyst placing area, a constant-temperature water tank, a gas guide pipe and a light source, wherein the reactor is provided with an inlet and an outlet, the catalyst placing area is arranged in the reactor, the light source is arranged above the reactor, the outlet of the sealed water container is communicated with the inlet of the reactor through the gas guide pipe, a product after the photocatalytic conversion of reaction gas is communicated with the outlet of the reactor and the gas guide pipe, and the reactor is arranged in the constant-temperature water tank.

Further, part of or all of the surface of the catalyst placing area is provided with a catalyst coating.

Optionally, the reaction product detection means comprises a gas chromatograph.

The invention also provides a gas phase photoreaction detection method, which adopts any one of the methane gas phase photoreaction detection devices, and comprises the following steps:

1) introducing reaction gas into the water vapor mixing device, and mixing the reaction gas with water vapor to obtain mixed gas;

2) introducing the mixed gas into the light reaction device, and carrying out catalytic conversion on the mixed gas under the conditions of illumination and a catalyst to obtain a product of catalytic conversion;

3) and introducing the product into the reaction product detection device, and detecting the product.

Optionally, at least one of the following technical features is also included:

1) in step 1), the reaction gas comprises carbon dioxide or methane;

2) in the step 1), the volume concentration of the reaction gas is between 95.0% and 100%;

3) in the step 1), the flow rate of the reaction gas is between 0.1m L/min and 200m L/min;

4) in the step 1), the temperature of water in the water vapor mixing device is between 10 and 90 ℃;

5) in the step 1), the water is placed in the closed water container, the closed water container is placed in the constant-temperature water tank, and the temperature of the constant-temperature water tank is between 10 ℃ and 90 ℃;

6) in the step 2), the light source for illumination comprises a xenon lamp light source, a sunlight light source or an L ED lamp light source;

7) in the step 2), the illumination time of the illumination is between 10min and 30 h;

8) in the step 2), the catalyst is placed in the catalyst placing area, the catalyst placing area is arranged in the reactor, the reactor is placed in the constant-temperature water tank, and the temperature of the constant-temperature water tank is between 10 ℃ and 90 ℃.

As described above, the gas phase photoreaction detection device and the reaction detection method thereof have the advantages of simple and convenient operation, and the whole device has simple structure design, convenient reaction, simple operation and easy disassembly; from the detection of reaction products, the whole device has good promotion effect on the reaction rate and the reaction process, and the reaction gas reacts at uniform and stable flow and uniform and stable temperature in the whole reaction process, so that the reaction rate of the catalyst under the action of accurate photocatalytic conversion is obtained, and the device has important significance on the whole photocatalytic conversion reaction.

Drawings

FIG. 1 is a schematic view of a gas phase photoreaction detection apparatus according to the present invention.

FIG. 2 is a flow chart of the detection method of the gas phase photoreaction detection apparatus of the present invention.

Description of the element reference numerals

1 reaction gas bearing device

11 reaction gas storage unit

12 gas volume flowmeter

13 one-way valve

2 steam mixing device

21 closed water container

211 inlet port

212 outlet port

22 constant temperature water tank

3 light reaction device

31 reactor

311 inlet

312 outlet

32 catalyst placement zone

33 constant temperature water tank

34 light source

4 reactant detection device

S1-S3

Detailed Description

The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention.

Please refer to fig. 1 and fig. 2. It should be noted that the drawings provided in the present embodiment are only for illustrating the basic idea of the present invention, and the drawings only show the components related to the present invention rather than being drawn according to the number, shape and size of the components in actual implementation, and the type, quantity and proportion of each component in actual implementation may be changed arbitrarily, and the layout of the components may be more complicated.

As shown in fig. 1, the present invention provides a gas phase photoreaction detection apparatus, which at least comprises:

the water vapor mixing device 2 is used for mixing the reaction gas with the water vapor to form mixed gas;

the light reaction device 3 is used for carrying out photocatalytic conversion on the mixed gas;

a reaction product detection device 4 for detecting the product of the photocatalytic conversion on line;

the water vapor mixing device 2, the light reaction device 3 and the reaction product detection device 4 are communicated in sequence.

According to the gas-phase photoreaction detection device, the water vapor mixing device 2, the photoreaction device 3 and the reaction product detection device 4 are communicated in sequence, so that the products of photocatalytic conversion can be efficiently and accurately detected in time; in addition, the detection device is simple in structural design, can conveniently realize a photocatalytic conversion process, is simple to operate and is easy to disassemble.

As shown in fig. 1, as an example, the gas phase photoreaction detection apparatus further includes a reaction gas carrier 1 for carrying and providing the reaction gas, and the reaction gas carrier 1, the water vapor mixing device 2, the photoreaction apparatus 3, and the reaction product detection apparatus 4 are sequentially communicated. As a preferable example of this example, the reaction gas bearing device 1 includes a reaction gas storage unit 11, a gas volume flow meter 12, a check valve 13, and a gas conduit, the reaction gas storage unit 11 communicates with the gas volume flow meter 12 through the gas conduit, the gas volume flow meter 12 communicates with the check valve 13 through the gas conduit, and the check valve 13 communicates with the water vapor mixing device 2 through the gas conduit. The gas volume flow meter 12 can make the reaction gas in the reaction gas storage unit 11 flow into the water vapor mixing device 2 uniformly and stably at a certain flow rate. The one-way valve 13 can effectively control the flow direction of the reaction gas, and prevent the reaction gas from flowing back to the reaction gas storage unit 11 to cause pollution.

As shown in fig. 1, the water vapor mixing device 2 includes a sealed water container 21, a constant temperature water tank 22, and a gas conduit, wherein the sealed water container 21 is provided with an inlet 211 and an outlet 212, the reaction gas passes through the gas conduit and enters the sealed water container 21 through the inlet 211 of the sealed water container 21, the outlet 212 of the sealed water container 21 is communicated with the photoreaction device 3 through the gas conduit, and the sealed water container 21 is placed in the constant temperature water tank 22. The constant-temperature water tank 22 can ensure that the reaction gas is dissolved and mixed with the water vapor in the water container 21 under the environment of uniform and stable temperature (the temperature is basically consistent with the temperature of the constant-temperature water tank 22) to form the mixed gas with uniform and stable temperature.

As shown in fig. 1, the photo-reaction device 3 includes, as an example, a reactor 31, a catalyst placing area 32, a constant temperature water tank 33, a gas conduit and a light source 34, the reactor 31 is provided with an inlet 311 and an outlet 312, the catalyst placing area 32 is disposed inside the reactor 31, the light source 34 is disposed vertically above the reactor 31, the outlet 211 of the closed water container 21 is communicated with the inlet 311 of the reactor 31 through the gas conduit, the product of the photocatalytic conversion of the reactant gas is communicated with the reactant detection device 4 through the outlet 312 of the reactor 31 and the gas conduit, and the reactor 31 is placed in the constant temperature water tank 33. The mixed gas is subjected to photocatalytic conversion in the photoreaction device 3, then the concentration of the product of the photocatalytic conversion is detected on line by the reaction product detection device 4, and finally the total reaction rate of the catalyst is obtained through calculation, however, the light source 34 shining into the reactor 31 causes the temperature in the reactor 31 to rise, which affects the catalytic performance of the catalyst, so that the total reaction rate of the catalyst obtained by the reaction product detecting means 4 is a result of the combined action of light and temperature, so that the corresponding relation between the illumination and the catalyst reaction rate cannot be obtained, and the influence of the illumination on the temperature rise of the reactor 31 is different along with the illumination intensity, the illumination time, the volume of the reactor and other factors, and thus the temperature rise value is also different, resulting in failure to obtain an accurate correspondence between the catalyst reaction rate and the illumination. By placing the reactor 31 in the constant temperature water tank 33, the temperature of the reactor 31 is ensured to be consistent in the whole photocatalytic conversion process, that is, when the light source 34 irradiates the reactor 31 to cause temperature increase, the temperature of the reactor 31 can be reduced under the action of the constant temperature water tank 33, so as to ensure that the reactor 31 is at a uniform and stable temperature, thereby eliminating the influence of the temperature change of the reactor 31 on the catalyst reaction rate, and obtaining an accurate corresponding relation between the catalyst reaction rate and the irradiation. As a preferred example of the present example, part or all of the surface of the catalyst placement area 32 is provided with a catalyst coating layer.

As an example, the reaction product detection means 4 comprises a gas chromatograph.

As shown in fig. 1 and fig. 2, the present invention further provides a gas phase photoreaction detection method, wherein the detection method employs the above-mentioned gas phase photoreaction detection apparatus for detection, and the performance and parameters of the detection apparatus refer to the foregoing examples, which are not repeated herein, and only the detection method is described. The detection method comprises the following steps:

s1, introducing reaction gas into the water vapor mixing device 2, and mixing the reaction gas with water vapor to obtain mixed gas;

s2, introducing the mixed gas into the light reaction device 3, and carrying out catalytic conversion on the mixed gas under the conditions of illumination and a catalyst to obtain a product of catalytic conversion;

and S3, introducing the product into the reaction product detection device 4, and detecting the product.

As an example, the detection method further comprises at least one of the following technical features:

1) in step S1, the reaction gas includes carbon dioxide or methane;

2) in step S1, the volume concentration of the reaction gas is between 95.0% and 100%;

3) in step S1, the flow rate of the reactant gas is between 0.1m L/min and 200m L/min, preferably, the flow rate of the reactant gas may be between 0.1m L0/min and 1m L1/min, 1m L2/min and 2m L3/min, 2m L4/min and 5m L5/min, 5m L/min and 10m L/min, 10m L/min and 100m L/min, 100m L/min and 180m L/min, and 180m L/min and 200m L/min;

4) in step S1, the temperature of the water in the water vapor mixing device is between 10 ℃ and 90 ℃, preferably, the temperature of the water in the water vapor mixing device can be between 10 ℃ and 20 ℃, between 20 ℃ and 30 ℃, between 30 ℃ and 40 ℃, or between 40 ℃ and 90 ℃;

5) in step S1, the water is placed in the sealed container of water, the sealed container of water is placed in the constant temperature water tank, the temperature of the constant temperature water tank 22 is between 10 ℃ and 90 ℃, preferably, the temperature of the constant temperature water tank 22 may be between 10 ℃ and 20 ℃, 20 ℃ to 30 ℃, 30 ℃ to 40 ℃, or 40 ℃ to 90 ℃;

6) in step S2, the light source for illumination includes a xenon lamp light source, a sunlight light source or a L ED lamp light source;

7) in step S2, the illumination time of the illumination is between 10min and 30h, preferably, the illumination time of the illumination may be between 10min and 3h, 3h and 10h, 10h and 15h, and 15min and 30 h;

8) in step S2, the catalyst is placed in the catalyst placement area, the catalyst placement area is disposed in the reactor, the reactor is placed in the constant-temperature water tank 33, the temperature of the constant-temperature water tank 33 is between 10 ℃ and 90 ℃, and preferably, the temperature of the constant-temperature water tank may be between 10 ℃ and 20 ℃, between 20 ℃ and 30 ℃, between 30 ℃ and 40 ℃, or between 40 ℃ and 90 ℃.

The gas phase photoreaction detection apparatus and the detection method thereof according to the present invention will be further described with reference to specific examples.