Gas-phase monoethanolamine concentration on-line detection device and gas-phase monoethanolamine concentration on-line detection method

Abstract

The invention belongs to the technical field of gas analysis and detection, and particularly relates to a gas-phase monoethanolamine concentration online detection device and method.The gas-phase monoethanolamine concentration online detection device utilizes a catalytic luminescent material and a matched photoelectric technology and comprises a pretreatment gas circuit module, an optical sensing module, a weak luminescence detection module, a data collecting and processing module and an intelligent management module; the online detection of the gas-phase monoethanolamine concentration is effectively realized. The method has the advantages of high accuracy, high sensitivity, high response speed, high stability and the like, and is high in practicability.

Description

Technical Field

[0001] The invention relates to the technical field of gas analysis and detection, and in particular to an online detection device and method for gas-phase monoethanolamine concentration. Background Art

[0002] Monoethanolamine (C2H7NO), also known as single ethanolamine, primary ethanolamine, etc., referred to as MEA, is a colorless viscous liquid with an ammonia smell at room temperature. It is soluble in water, and the solution is strongly alkaline. It can be miscible with water, ethanol and acetone. It is mainly used as a chemical reagent, pesticide, medicine, solvent, dye intermediate, rubber accelerator, corrosion inhibitor, surfactant, emulsifier, etc. It is an important fine chemical product and also an important chemical absorbent in the amine capture system.

[0003] N-bromosuccinimide (C4H4BrNO2), referred to as NBS, is a commonly used reagent in organic reactions. Its traditional application is the bromination of allylic hydrogen, benzylic hydrogen and carbonyl α-position hydrogen. In recent years, research has found that NBS can also be used as a catalyst, oxidant and many other aspects. Tin oxide (SnO2) is an important semiconductor sensor material. It is often doped and used in optoelectronic devices. The heterojunction effect between it and oxides can be used to improve the sensitivity of monomer oxide materials. It is a gas-sensitive material with high selectivity for organic amine volatile gases.

[0004] Organic amines have gradually become one of the research hotspots in the field of atmospheric environmental science. For the detection method of monoethanolamine, the most commonly used is derivatization gas chromatography analysis. The detection instrument is expensive, and the sample needs to be derivatized before analysis. The operation process is cumbersome, time-consuming, and prone to side reactions, and it is impossible to achieve online continuous measurement. The current domestic industry standard uses acid-base titration analysis. Although this method is simple, it has a large error. Therefore, it is necessary to establish a simple and accurate online detection method for monoethanolamine concentration. Summary of the invention

[0005] The purpose of the present invention is to provide an online detection device and method for gas phase monoethanolamine concentration to solve the problems raised in the above background technology. The present invention achieves the above purpose through the following technical solutions.

[0006] The invention provides an online detection device for gas-phase monoethanolamine concentration, which mainly comprises a pre-treatment gas circuit module, an optical sensing module, a weak luminescence detection module, a data acquisition and processing module and an intelligent management module which are connected in sequence; the pre-treatment gas circuit module comprises a sample gas flow controller, a carrier gas flow controller and a gas mixing chamber, and the sample gas flow controller and the carrier gas flow controller are arranged in parallel; the optical sensing module comprises a catalytic luminescence sensor and a light chamber component; the weak luminescence detection module comprises a filter and a photon counting detector which are arranged in sequence along a light beam propagation direction; the data acquisition and processing module collects and processes a light pulse number signal output by the photon counting detector, and then performs human-computer interaction and operation decision-making through the intelligent management module.

[0007] Furthermore, the catalytic luminescence sensor comprises a UV-grade quartz reactor with an inlet and an outlet and a ceramic electric heating tube coated with catalytic luminescence material; the optical chamber assembly comprises a light-shielding and heat-insulating box body and a light-guiding pipeline wrapped outside the UV-grade quartz reactor.

[0008] Furthermore, the photon counting detector includes a driven photomultiplier tube, a photoelectric amplifier, a signal discriminator, a pulse shaper and a photon pulse counter, and the detection wavelength range is 230-870nm.

[0009] Furthermore, the filter is an interference filter, and its characteristic central wavelength is 420-440nm.

[0010] The present invention also provides an online detection method for gas phase monoethanolamine concentration, using the above online detection device, the detection method includes the following steps: Step 1: The gas phase sample to be tested and the carrier are controlled by the sample gas flow controller and the carrier gas flow controller, enter the gas mixing chamber at set flow rates and are fully mixed, and then enter the UV grade quartz reactor; Step 2: The mixed gas and catalytic luminescent material are fully contacted in a UV-grade quartz reactor and heated by a ceramic electric heating tube to react. , the generated photon signal hγ passes through the light guide and filter in turn and is received by the photon counting detector; Step 3: The photomultiplier tube with driver uses the external photoelectric effect to convert the received photon signal hγ into a discrete electric pulse signal, amplifies the electric pulse signal in the photoelectric amplifier, and then selects the effective signal through the signal discriminator, separates it from the noise pulse, and sends it to the photon pulse counter for counting after the signal is trimmed by the pulse shaper; Step 4: The photon pulse counter transmits the photon counting signal to the data acquisition and processing module, and calculates the concentration of monoethanolamine gas in the sample to be tested in real time through the photon counting signal; During the online detection process, online human-computer interaction is realized through the intelligent management module, including status monitoring and fault diagnosis, intelligent sound and light warning, and intelligent calibration functions.

[0011] Furthermore, in step 4, the calculation formula for the concentration of monoethanolamine gas in the sample to be tested is lgC=klgI+b, where C is the concentration of monoethanolamine (mg / m 3 ), I is the photon counting signal, where k and b are linear coefficients, which are first determined by standard sample analysis and calibration.

[0012] Furthermore, the catalytic luminescent material is N-bromosuccinimide (C4H4BrNO2), or a composite material of N-bromosuccinimide (C4H4BrNO2) and tin dioxide (SnO2).

[0013] Further preferably, the molar ratio of the composite material of N-bromosuccinimide (C4H4BrNO2) and tin dioxide (SnO2) is 1:1-4:1.

[0014] Furthermore, the heating temperature of the ceramic electric heating tube is 200-300°C.

[0015] Furthermore, the carrier gas is air with a flow rate of 0-200 SCCM, and the flow rate of the gas phase sample to be measured is 0-100 SCCM.

[0016] The present invention has at least the following beneficial effects: The present invention provides an online detection device and method for gas-phase monoethanolamine concentration, which utilizes catalytic luminescent materials and supporting photoelectric technology to effectively realize continuous online detection of gas-phase monoethanolamine concentration. The method has the advantages of high accuracy, high sensitivity, fast response speed, strong stability, etc., and is highly practical.

[0017] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solution of the present invention, the drawings of the embodiments are briefly introduced below.

[0019] Figure 1 The present invention is a schematic structural diagram of an online detection device for gas-phase monoethanolamine concentration according to an embodiment of the present invention.

[0020] In the figure: 1-pretreatment gas path module, 2-optical sensing module, 3-weak luminescence detection module, 4-data acquisition and processing module, 5-intelligent management module.

[0021] Figure 2Schematic diagram of the structure of the pretreatment gas circuit module in the embodiment.

[0022] In the figure: 6-sample gas flow controller, 7-carrier gas flow controller, 8-mixing chamber.

[0023] Figure 3 Schematic diagram of the structure of the optical sensor module in the embodiment.

[0024] In the figure: 9-catalytic luminescence sensor, 10-light chamber assembly, 13-UV grade quartz reactor, 14-catalytic luminescence material, 15-ceramic electric heating tube, 16-light-shielding insulation box, 17-light guiding pipeline.

[0025] Figure 4 Schematic diagram of the structure of the photon technology detector in the embodiment.

[0026] In the figure: 18 - photomultiplier tube with driver, 19 - photoelectric amplifier, 20 - signal discriminator, 21 - pulse shaper and 22 - photon pulse counter. Implementation

[0027] The technical scheme in this embodiment will be described clearly and completely below in conjunction with the drawings in this embodiment. Obviously, the described embodiments are only partial embodiments, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. The principles and features of the present invention are described below in conjunction with the drawings, and the examples are only used to explain the present invention and are not used to limit the scope of the present invention. Example

[0028] A gas phase monoethanolamine concentration online detection device reference attachment Figure 1-4 , mainly comprising a pre-treatment gas path module (1), an optical sensing module (2), a weak luminescence detection module (3), a data acquisition and processing module (4), and an intelligent management module (5) which are connected in sequence.

[0029] The pretreatment gas path module (1) comprises a sample gas flow controller (6), a carrier gas flow controller (7) and a gas mixing chamber (8), wherein the sample gas flow controller (6) and the carrier gas flow controller (7) are arranged in parallel.

[0030] The optical sensing module (2) comprises a catalytic luminescence sensor (9) and a light chamber assembly (10); the catalytic luminescence sensor (9) comprises a UV-grade quartz reactor (13) having an inlet and an outlet and a ceramic electric heating tube (15) coated with a catalytic luminescence material (14); the light chamber assembly (10) comprises a light-shielding and heat-insulating box body (16) and a light-guiding pipeline (17) wrapped around the outside of the UV-grade quartz reactor (13).

[0031] The weak luminescence detection module (3) comprises a filter (11) and a photon counting detector (12), which are arranged in sequence along the propagation direction of the light beam; the photon counting detector (12) comprises a driven photomultiplier tube (18), a photoelectric amplifier (19), a signal discriminator (20), a pulse shaper (21) and a photon pulse counter (22), and the detection wavelength range is 230-870nm; the filter (11) is an interference filter, and its characteristic central wavelength is 420-440nm.

[0032] The data collection and processing module (4) collects and processes the light pulse number signal output by the photon counting detector (12), and then performs human-computer interaction and operation decision-making through the intelligent management module (5).

[0033] In the embodiment, the online detection method using the above-mentioned gas phase monoethanolamine concentration online detection device mainly includes the following steps: Step 1: The gas phase sample to be tested and the carrier gas are controlled by the sample gas flow controller (6) and the carrier gas flow controller (7), enter the gas mixing chamber (8) at set flow rates, are fully mixed, and then enter the UV-grade quartz reactor (13), thereby achieving the purpose of precise flow control and mixing; It is worth noting that the carrier gas is air with a flow rate of 0-200 SCCM, and the flow rate of the gas phase sample to be measured is 0-100 SCCM; Step 2: The mixed gas and the catalytic luminescent material (14) are fully contacted in a UV-grade quartz reactor (13) and heated by a ceramic electric heating tube (15) at a heating temperature of 200-300°C to carry out the reaction. The generated photon signal hγ passes through the light guide pipe (17) and the filter (11) in turn, and is received by the photon counting detector (12), thereby completing the purpose of catalyzing the light reflection reaction and generating photons; It is noteworthy that the catalytic luminescent material (14) is N-bromosuccinimide (C4H4BrNO2) or a composite material of N-bromosuccinimide (C4H4BrNO2) and tin dioxide (SnO2), and the molar ratio of the composite material is 1:1-4:1.

[0034] Step 3: The driven photomultiplier tube (18) uses the external photoelectric effect to convert the received photon signal hγ into an electric pulse discrete signal, and then amplifies the electric pulse signal in the photoelectric amplifier (19). Then, the effective signal is screened out by the signal discriminator (20), and the effective signal is separated from the noise pulse. After the signal is trimmed by the pulse shaper (21), it is sent to the photon pulse counter (22) for counting, thereby completing the purpose of photoelectric conversion and counting; Step 4: The photon pulse counter (22) transmits the photon counting signal to the data acquisition and processing module (4), and calculates the concentration of monoethanolamine gas in the sample to be tested in real time through the photon counting signal. The calculation formula is: lgC=klgI+b, where C is the monoethanolamine concentration (mg / m 3 ), I is the photon counting signal, k and b are linear coefficients; It is worth noting that the linear coefficients k and b in the formula are first determined by standard sample analysis and calibration; During the online detection process, the intelligent management module (5) realizes online human-computer interaction, including but not limited to functions such as status monitoring and fault diagnosis, intelligent sound and light warning, and intelligent calibration.

[0035] The following examples use the above-mentioned gas phase monoethanolamine concentration online detection device for online detection. Example 1

[0036] The gas sample to be tested has a controlled flow rate of 60 SCCM, and the air has a controlled flow rate of 100 SCCM. After entering the gas mixing chamber and being fully mixed, it enters the UV-grade quartz reactor and is heated to 200°C by a ceramic electric heating tube. Under the catalytic action of the catalytic luminescent material N-bromosuccinimide (C4H4BrNO2), the photon signal hγ generated by the reaction passes through the light guide and the 420nm interference filter in turn.

[0037] When the concentration is 50.0 mg / m 3 The gas phase monoethanolamine standard sample was passed into the detection device provided in the embodiment, and the number of photons collected was 16280; when the concentration was 9.8 mg / m 3 The gas phase monoethanolamine standard sample was introduced into the detection device provided by the present invention, and the number of photons collected was 2356.

[0038] According to the above data, the calculation formula is: lgC = klgI + b (1), (where C is the concentration of monoethanolamine (mg / m 3 ), I is the photon counting signal, k and b are linear coefficients), k=0.8431, b=-1.8519 are calculated, and the calculation formula is: lgC=0.8431lgI-1.8519 (2).

[0039] When the number of photons detected by the photon counting detector is 3579, the data acquisition and processing module calculates the concentration of monoethanolamine gas in the sample to be tested as 13.941 mg / m 3 . Comparative Example 1

[0040] The same concentration of sample gas (gas phase monoethanolamine containing gas phase sodium hydroxide) was tested by direct acid-base titration analysis. Since the inorganic base components mixed in monoethanolamine could not be detected, the test result showed that the concentration of monoethanolamine was 19.44 mg / m 3 The detection time is 2 minutes; the two-step potentiometric titration analysis method is used for detection (dilute hydrochloric acid potentiometric titration of sodium hydroxide, high concentration hydrochloric acid titration of total alkali), and the detection result shows that the concentration of monoethanolamine is 13.23 mg / m 3 , the concentration of sodium hydroxide is 6.21 mg / m 3 , the detection time is 5 minutes; using the online detection method of the gas phase monoethanolamine concentration online detection device of the present invention, the monoethanolamine concentration is 13.23mg / m 3 , the detection time is less than 15 seconds. Example 2

[0041] The gas phase sample to be tested is controlled to have a flow rate of 60 SCCM, and the air is controlled to have a flow rate of 100 SCCM. After entering the gas mixing chamber and being fully mixed, it enters a UV-grade quartz reactor and is heated to 200°C by a ceramic electric heating tube. Under the catalytic action of a composite material having a molar ratio of 1:1 between N-bromosuccinimide (C4H4BrNO2) and tin dioxide (SnO2), the photon signal hγ generated by the reaction passes through a light-guiding pipeline and a 420 nm interference filter in turn. This method is used to detect the concentration of monoethanolamine gas in the sample to be tested, and the application effect is the same as that of Example 1. Example 3

[0042] The gas sample to be tested is controlled to have a flow rate of 40 SCCM, and the air is controlled to have a flow rate of 80 SCCM. After entering the gas mixing chamber for full mixing, it enters the UV-grade quartz reactor and is heated to 250°C by a ceramic electric heating tube. Under the catalytic action of the catalytic luminescent material, N-bromosuccinimide (C4H4BrNO2), the photon signal hγ generated by the reaction passes through the light-guiding pipeline and the 430nm interference filter in turn. This method is used to detect the concentration of monoethanolamine gas in the sample to be tested. Example 4

[0043] The gas phase sample to be tested is controlled to have a flow rate of 40 SCCM, and the air is controlled to have a flow rate of 80 SCCM. After entering the gas mixing chamber for thorough mixing, the gas enters a UV-grade quartz reactor and is heated to 250°C by a ceramic electric heating tube. Under the catalytic action of a composite material having a molar ratio of 2:1 of N-bromosuccinimide (C4H4BrNO2) and tin dioxide (SnO2), the photon signal hγ generated by the reaction passes through a light-guiding pipeline and a 430 nm interference filter in turn. This method is used to detect the concentration of monoethanolamine gas in the sample to be tested, and the application effect is the same as that of Example 3. Example 5

[0044] The gas sample to be tested is controlled to have a flow rate of 80 SCCM, and the air is controlled to have a flow rate of 170 SCCM. After entering the gas mixing chamber for full mixing, it enters the UV-grade quartz reactor and is heated to 275°C by a ceramic electric heating tube. Under the catalytic action of the catalytic luminescent material N-bromosuccinimide (C4H4BrNO2), the photon signal hγ generated by the reaction passes through the light-guiding pipeline and the 440nm interference filter in turn. This method is used to detect the concentration of monoethanolamine gas in the sample to be tested. Example 6

[0045] The gas phase sample to be tested is controlled to have a flow rate of 80 SCCM, and the air is controlled to have a flow rate of 170 SCCM. After entering the gas mixing chamber for thorough mixing, the gas enters a UV-grade quartz reactor and is heated to 275°C by a ceramic electric heating tube. Under the catalytic action of a composite material having a molar ratio of 3:1 of N-bromosuccinimide (C4H4BrNO2) and tin dioxide (SnO2), the photon signal hγ generated by the reaction passes through a light-guiding pipeline and a 440 nm interference filter in turn. This method is used to detect the concentration of monoethanolamine gas in the sample to be tested, and the application effect is the same as that of Example 5. Example 7

[0046] The gas phase sample to be tested is controlled to have a flow rate of 80 SCCM, and the air is controlled to have a flow rate of 170 SCCM. After entering the gas mixing chamber for thorough mixing, the gas enters a UV-grade quartz reactor and is heated to 275°C by a ceramic electric heating tube. Under the catalytic action of a composite material having a molar ratio of 4:1 of N-bromosuccinimide (C4H4BrNO2) and tin dioxide (SnO2), the photon signal hγ generated by the reaction passes through a light-guiding pipeline and a 440 nm interference filter in turn. This method is used to detect the concentration of monoethanolamine gas in the sample to be tested, and the application effect is the same as that of Example 5. Example 8

[0047] The gas phase sample to be tested is controlled to have a flow rate of 70 SCCM, and the air is controlled to have a flow rate of 150 SCCM. After entering the gas mixing chamber for full mixing, it enters the UV-grade quartz reactor and is heated to 300°C by a ceramic electric heating tube. Under the catalytic action of a composite material whose catalytic material is N-bromosuccinimide (C4H4BrNO2) and tin dioxide (SnO2) with a molar ratio of 3:1, the photon signal hγ generated by the reaction passes through the light guide and the 420nm interference filter in turn. This method is used to detect the concentration of monoethanolamine gas in the sample to be tested. Example 9

[0048] The gas phase sample to be tested is controlled to have a flow rate of 70 SCCM, and the air is controlled to have a flow rate of 150 SCCM. After entering the gas mixing chamber for thorough mixing, it enters a UV-grade quartz reactor and is heated to 300°C by a ceramic electric heating tube. Under the catalytic action of a composite material having a molar ratio of 3:1 of N-bromosuccinimide (C4H4BrNO2) and tin dioxide (SnO2), the photon signal hγ generated by the reaction passes through a light-guiding pipeline and a 430 nm interference filter in turn. This method is used to detect the concentration of monoethanolamine gas in the sample to be tested, and the application effect is the same as that of Example 8. Example 10

[0049] The gas phase sample to be tested is controlled to have a flow rate of 70 SCCM, and the air is controlled to have a flow rate of 150 SCCM. After entering the gas mixing chamber and being fully mixed, it enters a UV-grade quartz reactor and is heated to 300°C by a ceramic electric heating tube. Under the catalytic action of a composite material having a molar ratio of 3:1 of N-bromosuccinimide (C4H4BrNO2) and tin dioxide (SnO2), the photon signal hγ generated by the reaction passes through a light-guiding pipeline and a 440 nm interference filter in turn. This method is used to detect the concentration of monoethanolamine gas in the sample to be tested, and the application effect is the same as that of Example 8.

[0050] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

[0051] Parts of the present invention that are not described in detail are well known to those skilled in the art.

Claims

1. A gas phase monoethanolamine concentration online detection device, characterized in that: It comprises a pre-treatment gas circuit module, an optical sensing module, a weak luminescence detection module, a data acquisition and processing module and an intelligent management module which are connected in sequence; the pre-treatment gas circuit module comprises a sample gas flow controller, a carrier gas flow controller and a gas mixing chamber, and the sample gas flow controller and the carrier gas flow controller are arranged in parallel; the optical sensing module comprises a catalytic luminescence sensor and a light chamber component; the weak luminescence detection module comprises a filter and a photon counting detector which are arranged in sequence along the propagation direction of the light beam; the data acquisition and processing module collects and processes the light pulse number signal output by the photon counting detector, and then performs human-computer interaction and operation decision-making through the intelligent management module.

2. The device for online detection of gas phase monoethanolamine concentration as claimed in claim 1, characterized in that: The catalytic luminescence sensor comprises a UV-grade quartz reactor with an inlet and an outlet and a ceramic electric heating tube coated with catalytic luminescence material; the optical chamber assembly comprises a light-shielding and heat-insulating box body and a light-guiding pipeline wrapped outside the UV-grade quartz reactor.

3. The device for online detection of gas phase monoethanolamine concentration as claimed in claim 1, characterized in that: The photon counting detector comprises a driven photomultiplier tube, a photoelectric amplifier, a signal discriminator, a pulse shaper and a photon pulse counter, and the detection wavelength range is 230-870nm.

4. The device for online detection of gas phase monoethanolamine concentration as claimed in claim 1, characterized in that: The filter is an interference filter, and its characteristic central wavelength is 420-440nm.

5. An online detection method using the online detection device for gas-phase monoethanolamine concentration according to any one of claims 1 to 4, characterized in that: The detection method comprises the following: Step 1: The gas phase sample to be tested and the carrier are controlled by the sample gas flow controller and the carrier gas flow controller, enter the gas mixing chamber at set flow rates and are fully mixed, and then enter the UV grade quartz reactor; Step 2: The mixed gas and the catalytic luminescent material are fully contacted in a UV-grade quartz reactor and heated by a ceramic electric heating tube for reaction. The generated photon signal passes through the light guide and filter in turn and is received by the photon counting detector; Step 3: The photomultiplier tube with driver uses the external photoelectric effect to convert the received photon signal hγ into a discrete electric pulse signal, amplifies the electric pulse signal in the photoelectric amplifier, and then selects the effective signal through the signal discriminator, separates it from the noise pulse, and sends it to the photon pulse counter for counting after the signal is trimmed by the pulse shaper; Step 4: The photon pulse counter transmits the photon counting signal to the data acquisition and processing module, and calculates the concentration of monoethanolamine gas in the sample to be tested in real time through the photon counting signal; During the online detection process, online human-computer interaction is realized through the intelligent management module, including status monitoring and fault diagnosis, intelligent sound and light warning, and intelligent calibration functions.

6. The online detection method according to claim 5, characterized in that: In step 4, the calculation formula for the concentration of monoethanolamine gas in the sample to be tested is lgC=klgI+b, where C is the concentration of monoethanolamine (mg / m 3 ), I is the photon counting signal, where k and b are linear coefficients, which are first determined by standard sample analysis and calibration.

7. The online detection method according to claim 5, characterized in that: The catalytic luminescent material is N-bromosuccinimide (C4H4BrNO2), or a composite material of N-bromosuccinimide (C4H4BrNO2) and tin dioxide (SnO2).

8. The online detection method according to claim 7, characterized in that: The molar ratio of the composite material of N-bromosuccinimide (C4H4BrNO2) and tin dioxide (SnO2) is 1:1-4:

1.

9. The online detection method according to claim 5, characterized in that: The heating temperature of the ceramic electric heating tube is 200-300°C.

10. The online detection method according to claim 5, characterized in that: The carrier gas is air with a flow rate of 0-200 SCCM, and the flow rate of the gas phase sample to be measured is 0-100 SCCM.

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