CN112908830A - Atmospheric pressure photoionization source device for detecting volatile organic compounds in water - Google Patents
Atmospheric pressure photoionization source device for detecting volatile organic compounds in water Download PDFInfo
- Publication number
- CN112908830A CN112908830A CN201911225074.4A CN201911225074A CN112908830A CN 112908830 A CN112908830 A CN 112908830A CN 201911225074 A CN201911225074 A CN 201911225074A CN 112908830 A CN112908830 A CN 112908830A
- Authority
- CN
- China
- Prior art keywords
- electrode
- capillary
- atmospheric pressure
- bottle
- pressure photoionization
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J49/00—Particle spectrometers or separator tubes
- H01J49/02—Details
- H01J49/10—Ion sources; Ion guns
- H01J49/16—Ion sources; Ion guns using surface ionisation, e.g. field-, thermionic- or photo-emission
- H01J49/161—Ion sources; Ion guns using surface ionisation, e.g. field-, thermionic- or photo-emission using photoionisation, e.g. by laser
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J49/00—Particle spectrometers or separator tubes
- H01J49/02—Details
- H01J49/04—Arrangements for introducing or extracting samples to be analysed, e.g. vacuum locks; Arrangements for external adjustment of electron- or ion-optical components
- H01J49/0404—Capillaries used for transferring samples or ions
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J49/00—Particle spectrometers or separator tubes
- H01J49/02—Details
- H01J49/04—Arrangements for introducing or extracting samples to be analysed, e.g. vacuum locks; Arrangements for external adjustment of electron- or ion-optical components
- H01J49/0431—Arrangements for introducing or extracting samples to be analysed, e.g. vacuum locks; Arrangements for external adjustment of electron- or ion-optical components for liquid samples
- H01J49/0445—Arrangements for introducing or extracting samples to be analysed, e.g. vacuum locks; Arrangements for external adjustment of electron- or ion-optical components for liquid samples with means for introducing as a spray, a jet or an aerosol
- H01J49/045—Arrangements for introducing or extracting samples to be analysed, e.g. vacuum locks; Arrangements for external adjustment of electron- or ion-optical components for liquid samples with means for introducing as a spray, a jet or an aerosol with means for using a nebulising gas, i.e. pneumatically assisted
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J49/00—Particle spectrometers or separator tubes
- H01J49/02—Details
- H01J49/06—Electron- or ion-optical arrangements
- H01J49/067—Ion lenses, apertures, skimmers
Landscapes
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- Dispersion Chemistry (AREA)
- Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
Abstract
The invention relates to a mass spectrometer, in particular to an atmospheric pressure photoionization source device for detecting volatile organic compounds in water. The device comprises a dynamic purging bubbling device and an atmospheric pressure photoionization source. The dynamic purging bubbling device mainly comprises a glass small bottle, four capillary tubes, a bubbling bottle outlet and a constant-temperature water bath kettle. The atmospheric pressure photoionization source comprises an ionization source cavity, a vacuum ultraviolet lamp, a repulsion electrode, a focusing electrode, a transmission electrode, a mass spectrum sample introduction metal capillary, a reagent gas sample introduction port, a high-humidity sample introduction port and a supplementary gas introduction port. The high-humidity sample gas purged from the bubbler was all admitted to an atmospheric pressure photoionization source. The invention improves the stability of detection, and the matrix in water has little influence on the detection of the sample; the absorption of photons by neutral molecules and the consumption of reagent ions are reduced; the introduction of the reagent gas can greatly improve the ionization efficiency. The designed atmospheric pressure photoionization source can realize the rapid and high-sensitivity detection of a high-humidity sample.
Description
Technical Field
The invention relates to a mass spectrometer, in particular to an atmospheric pressure photoionization source device for detecting volatile organic compounds in water.
Background
With the development of industry and the growth of population, water pollution has become a prominent worldwide problem. The safety of drinking water, as well as all water resources actually or potentially destined for drinking, need to be assessed to ensure public health. The Minnesota department of health has established standards for drinking water for the health risk limits of 23 VOCs. The united states Environmental Protection Agency (EPA) currently recommends the use of purge trap GC-MS and static or dynamic headspace GC as standard methods for the evaluation of VOCs in water. In the national standard GB/T5750.8-2006 Standard inspection method for Drinking Water-organic index ", an off-line analysis method based on gas chromatography is adopted, and complicated sample pretreatment processes such as headspace balance, solvent extraction and the like are required. Although the method has high accuracy of analysis results, the detection speed is slow, the cost is high, and the rapid online analysis and screening of a large amount of samples to be detected are difficult to realize.
The mass spectrometry has the advantages of high analysis speed, high resolution and sensitivity and strong qualitative capability. Atmospheric pressure ionization techniques such as electrospray ionization, atmospheric pressure chemical ionization, atmospheric pressure photoionization and the like are suitable for rapid and online analysis of organic matter samples. However, mass spectrometry needs to work in a high vacuum environment, a liquid sample cannot directly enter a mass spectrometry cavity for ionization and analysis, and the liquid sample is usually detected after being processed by using static or dynamic headspace, solid phase microextraction and other technologies. However, these methods are complicated and time-consuming to operate.
In 2013, plum sea and the like invented a composite ionization source based on vacuum ultraviolet photoionization and atmospheric pressure ionization (patent application No. 201310687505.5). The vacuum ultraviolet light in the composite ionization source ionizes polar and nonpolar molecules, and the ionizing ionization energy of the atmospheric pressure ionization source is higher than that of a compound of vacuum ultraviolet light photon energy, so that the range of the ionizable compound is widened; in addition, sample molecules which are not ionized in the atmospheric pressure ionization source can be secondarily ionized by vacuum ultraviolet light after entering the cavity of the ionization chamber, so that the ionization efficiency and the detection sensitivity are improved. However, when the invention is used for directly detecting a high-humidity sample, the sensitivity is seriously reduced due to the absorption of photons by water molecules.
In 2016, Panyang et al invented a rapid online atmospheric pressure photoionization mass spectrometry device for active ingredients in complex matrices (patent application No. 201610116956.7). The pretreatment device comprises an ultrasonic atomization mechanism, a volatile solvent introduction mechanism and a heating transmission mechanism. A sample to be tested containing a complex matrix (such as soil, poor milk powder, food containing illegal additives, root, stem and leaf of medicinal plants and the like left in an explosion field) is directly put into an ultrasonic atomization mechanism, is subjected to ultrasonic atomization extraction, is subjected to ultrasonic atomization and heating gasification treatment, is converged with a volatile solvent and then reaches the front end of an atmospheric pressure photoionization source to be ionized, and therefore sensitive, rapid and reliable qualitative and quantitative analysis is achieved. The vacuum ultraviolet lamp is placed in an open manner. Solvent molecules in complex matrices absorb photons from the uv lamp resulting in reduced sensitivity.
In 2017, florists et al invented a device for enriching, sampling and ionizing volatile organic compounds in a liquid sample (patent application No. 201711203622.4). The device includes: a venturi tube, a membrane enrichment sampling tube and an atmospheric pressure ionization source. The Venturi tube comprises a gas transmission tube, a contraction tube, a throat tube and an expansion tube which are coaxially arranged in sequence; the inlet end of the gas delivery pipe is connected with an external high-pressure carrier gas source; the membrane enrichment sampling pipe is a tubular membrane and penetrates through the liquid sampling pipe; a through hole is arranged on the outer wall surface of the throat of the Venturi tube, and the outlet end of the membrane enrichment sampling tube is hermetically connected with the through hole; a mass spectrum sample introduction Skimmer electrode is arranged at the rear end of the outlet of the expansion pipe, and an ionization region of the atmospheric pressure ionization source is arranged in a region between the Venturi tube and the mass spectrum sample introduction Skimmer electrode. The method does not need sample pretreatment, and can realize high-flux, quick and on-line monitoring of the VOCs in the liquid sample. But the complex matrix in the liquid can block the membrane, so the complex matrix liquid sample cannot be directly used for detecting the complex matrix liquid sample.
Therefore, the invention designs an atmospheric pressure photoionization source device for detecting volatile organic compounds in water. After the stable and rapid purging of the bubbling bottle, VOCs in the liquid sample directly enters an atmospheric pressure photoionization source for analysis. The designed atmospheric pressure photoionization source is a soft ionization source, the introduction of reagent gas can improve the ionization efficiency, and the introduction of the focusing electrode can reduce the absorption of water molecules to photons and the consumption of reagent ions, thereby realizing the rapid and high-sensitivity detection of high-humidity samples.
Disclosure of Invention
The invention aims to provide an atmospheric pressure photoionization source device for detecting volatile organic compounds in water. The dynamic purging bubbling device and the atmospheric pressure photoionization source are utilized to realize the rapid and high-sensitivity detection of the volatile organic compounds in water without sample pretreatment. In order to achieve the purpose, the invention adopts the technical scheme that:
an atmospheric pressure photoionization source device for detection of volatile organic compounds in water, comprising: a dynamic purging bubbling device and an atmospheric pressure photoionization source.
The dynamic purging bubbling device comprises four capillary tubes, a glass small bottle, a liquid sample, a constant-temperature water bath kettle and a bubbling bottle outlet; and blowing gas is introduced into the four capillary tubes, the liquid sample immerses the bottoms of the capillary tubes, and volatile organic compounds in the liquid sample enter the atmospheric pressure photoionization source cavity through the outlet of the bubbling bottle and the heating device.
The dynamic purging and bubbling device comprises a constant-temperature water bath kettle and a small glass bottle, wherein the small glass bottle is a container with an opening at the upper end, and a sealing cover hermetically connected with the upper opening end of the container is arranged at the upper opening end of the container; placing the small glass bottle in a water bath of a constant-temperature water bath kettle; the glass small bottle is filled with a liquid sample, more than 1 capillary extends into the liquid sample below the liquid level in the glass small bottle from the upper part or the sealing cover, and a bubbling bottle outlet is arranged at the upper part or the sealing cover of the glass small bottle; introducing purge gas into the capillary tube to enter the liquid level of the liquid sample, and allowing volatile organic compounds in the liquid sample to flow out through the outlet of the bubbling bottle;
the atmospheric pressure photoionization source comprises an ionization source cavity and a capillary electrode;
the capillary electrode is a flat plate electrode, and a metal capillary tube penetrating through the flat plate body is arranged in the middle of the flat plate electrode to form the capillary electrode;
the ionization source cavity is a closed container, a flat-plate-shaped repulsion electrode with a through hole in the middle, a flat-plate-shaped focusing electrode with a through hole in the middle and more than 1 flat-plate-shaped transmission electrodes with through holes in the middle are sequentially arranged in parallel on the container from top to bottom at intervals, a through hole is formed in the lower end face of the container below the transmission electrodes, a capillary electrode is arranged at the through hole, the lower surface of the capillary electrode is hermetically connected with the bottom surface of the container or the peripheral edge of the capillary electrode is hermetically connected with the inner wall surface of the through hole in the lower end face of the container, the upper opening end of a metal capillary of the capillary electrode is positioned below the through hole; the repulsion electrode, the focusing electrode, the middle through hole of the transmission electrode and the metal capillary are coaxial;
a vacuum ultraviolet lamp is arranged above the repulsion electrode of the container, and a light outlet of the vacuum ultraviolet lamp faces to the middle through hole of the repulsion electrode;
a reagent gas inlet pipe is arranged on the side wall surface of the container, and the gas outlet of the reagent gas inlet pipe faces to the area between the repulsion electrode and the focusing electrode;
a high-humidity sample inlet pipe is arranged on the side wall surface of the container, and the air outlet of the high-humidity sample inlet pipe faces to the area between the focusing electrode and the transmission electrode; the air inlet of the high-humidity sample inlet pipe is connected with the outlet of the bubbling bottle;
and a supplementary gas inlet pipe is arranged on the side wall surface of the container, and the gas outlet of the supplementary gas inlet pipe faces to the area between the transmission electrode and the capillary electrode.
An electric heating element is arranged on the outer wall surface of the pipeline connecting the air inlet of the high-humidity sample inlet pipe and the outlet of the bubbling bottle.
The purge gas and the make-up gas are both dry nitrogen or air; the reagent gas is acetone, butanone, toluene, anisole, ethanol or chlorobenzene with certain concentration.
The capillary is a metal capillary or a PEEK capillary, the lengths of the capillaries are the same, the outer diameter is 1/16 inch, the inner diameter is 100-500 mu m, and the distance from the bottom of the capillary to the bottom of the glass vial is 1-3 mm.
The glass small bottle consists of a sealing cover and a bottle body, the total volume of the inside of the glass small bottle is 10-30 mL, and the joint of the sealing cover and the bottle body is designed by grinding.
The reagent gas inlet, the high-humidity sample inlet and the supplementary gas inlet are all made of polytetrafluoroethylene.
The liquid sample is immersed at the bottom of the capillary tube, and the volume of the liquid sample is 2-10 mL. The liquid sample can be domestic sewage, experimental sewage, sewage treatment plant wastewater, river water, seawater and the like.
During detection, the small glass bottle is placed in a constant-temperature water bath kettle for heat preservation, and the water temperature in the constant-temperature water bath kettle is kept between room temperature and 90 ℃.
The repulsion electrode, the focusing electrode, the transmission electrode and the capillary tube electrode are all round stainless steel electrodes, the outer diameters of the repulsion electrode, the focusing electrode, the transmission electrode and the capillary tube electrode are the same, the repulsion electrode, the focusing electrode, the transmission electrode and the capillary tube electrode are all coaxially arranged with the vacuum ultraviolet lamp, and the spacing distance between the electrodes is 4-10 mm; the repulsion electrode is tightly attached to the edge of the vacuum ultraviolet lamp light window, and the inner diameter of the repulsion electrode is 8 mm; the inner diameter of the focusing electrode is 2-4 mm; the inner diameter of the transmission electrode is 8-20 mm; the focusing electrode divides the ionization source into two parts, namely a reagent ion area (a middle area between the repulsion electrode and the focusing electrode) and a sample area (a middle area between the focusing electrode and the transmission electrode).
The repulsion electrode, the focusing electrode, the transmission electrode and the ground are connected with resistors with the same resistance value. A direct current voltage of 0-3000V is applied to the repulsion electrode; the capillary electrode is applied with a DC voltage of 0-500V.
The metal capillary is fixed in the center of the capillary electrode, the outer diameter is 1/16 inch, the inner diameter is 0.5-1 mm, the length of the metal capillary extending into the ionization cavity is adjustable, and the distance between the capillary electrode and the transmission electrode cannot be exceeded.
The dynamic purging and bubbling device provided by the invention adopts the metal or PEEK capillary tube with smaller aperture to purge the liquid sample, and the purging is more uniform and stable. High-humidity gas containing a volatile organic compound sample blown out of the bubbling bottle directly enters a sample area of an atmospheric pressure photoionization source after being heated, and sample molecules enter mass spectrum detection after fully reacting with reagent ions. The designed atmospheric pressure photoionization source is a soft ionization source, the introduction of reagent gas can improve the ionization efficiency, and the introduction of the focusing electrode can reduce the absorption of water molecules to photons and the consumption of reagent ions, thereby realizing the rapid and high-sensitivity detection of high-humidity samples.
Drawings
Fig. 1 is a schematic structural diagram of an atmospheric pressure photoionization source device for detecting volatile organic compounds in water.
1. A dynamic purging bubbling device; 2. an atmospheric pressure photoionization source; 3. a capillary tube; 4. a glass vial; 5. a liquid sample; 6. a constant-temperature water bath kettle; 7. bubbler outlet (high humidity sample inlet); 8. purging gas; 9. water; 10. a heating device; 11. an ionization source cavity; 12. a reagent gas inlet; 13. a make-up gas inlet; 14. a reagent gas; 15. make-up air; 16. a vacuum ultraviolet lamp; 17. a repulsion electrode; 18. a focusing electrode; 19. a transmission electrode; 20. a capillary electrode; 21. a metal capillary tube; 22. a mass spectrometer; 23. a sealing cover; 24. a bottle body.
Fig. 2 is a mass spectrogram obtained when acetone is used as a reagent gas and trimethylamine and triethylamine in water are detected in an atmospheric pressure photoionization source device for detecting volatile organic compounds in water.
Wherein the dimer hydrogenation peak of acetone ([ D ]2H]+) m/z117.09 is the main reagent ion peak, m/z59.05 is the acetone monomer hydrogenation peak ([ DH)]+) And m/z76.05 is the clustering peak ([ D + H) of acetone monomer and water2O]+) And m/z134.09 is the peak of acetone dimer in water cluster ([ D ]2+H2O]+) The water cluster peak occurs because the humidity of the sample is high. m/z60.08 is the characteristic peak of trimethylamine (hydrogenation peak MH]+) And m/z102.13 is the characteristic peak of triethylamine (hydrogenation peak MH)]+)。
Detailed Description
Embodiment example 1 of the present invention will be further described by way of example with reference to the accompanying drawings
Referring to fig. 1, a schematic structural diagram of an atmospheric pressure photoionization source device for detecting volatile organic compounds in water according to the present invention is shown. The device consists of a dynamic purging bubbling device 1 and an atmospheric pressure photoionization source 2.
The dynamic purging bubbling device 1 comprises four capillary tubes 3, a glass vial 4, a liquid sample 5, a constant-temperature water bath 6 and a bubbling bottle outlet 7; the purge gas 8 is introduced into the four capillary tubes 3, the liquid sample 5 is immersed at the bottom of the capillary tubes 3, and the volatile organic compounds in the liquid sample 5 enter the atmospheric pressure photoionization source cavity 11 through the outlet 7 of the bubbling bottle and the heating device 10.
The atmospheric pressure photoionization source 2 comprises an ionization source cavity 11, a reagent gas inlet 12, a high-humidity sample inlet (namely a bubbling bottle outlet 7), a supplementary gas inlet 13, a vacuum ultraviolet lamp 16, a repulsion electrode 17, a focusing electrode 18, a transmission electrode 19, a capillary electrode 20 and a metal capillary 21.
The purge gas 8 and the make-up gas 15 are both dry nitrogen; the reagent gas 14 was 1550ppmv acetone.
The four capillaries 3 are PEEK capillaries of the same length with an outer diameter of 1/16 inch and an inner diameter of 250 μm, the bottom of the capillaries 3 being 1mm from the bottom of the glass vial 4.
The glass bottle 4 consists of a sealing cover 23 and a bottle body 24, the total volume of the inside of the glass bottle is 10mL, and the joint part of the sealing cover and the bottle body adopts a ground design.
The liquid sample 5 is immersed in the bottom of the capillary 3 in a volume of 2 mL. Liquid samples are trimethylamine, triethylamine solutions or seawater samples with standard concentrations.
During detection, the small glass bottle is placed in a constant-temperature water bath 6 for heat preservation, and the water temperature in the constant-temperature water bath is kept at 60 ℃ at room temperature.
The repulsion electrode 17, the focusing electrode 18, the transmission electrode 19 and the capillary electrode 20 are all flat annular stainless steel electrodes with the same outer diameter and are coaxially arranged with the vacuum ultraviolet lamp 16, and the spacing distance between the electrodes is 8.5 mm; the repulsion electrode 17 is tightly attached to the edge of the light window of the vacuum ultraviolet lamp 16, and the inner diameter is 8 mm; the inner diameter of the focusing electrode 18 is 3 mm; the inner diameter of the transmission electrode 196 is 8 mm; the focusing electrode divides the ionization source into two parts, namely a reagent ion area (a middle area between the repulsion electrode and the focusing electrode) and a sample area (a middle area between the focusing electrode and the transmission electrode).
The repelling electrode 17, the focusing electrode 18, the transmission electrode 19 and the ground are connected with resistors with the same resistance value, and the resistance value is 2M omega. A 1000V DC voltage is applied to the repulsion electrode 17; a dc voltage of 50V is applied to the capillary electrode 20.
The metal capillary 21 is fixed in the center of the capillary electrode, the outer diameter is 1/16 inch, the inner diameter is 0.5mm, the length extending into the ionization chamber is 8mm, and the total length is 3.8 mm.
A reagent gas inlet 12 is arranged between the repulsion electrode and the focusing electrode, a high-humidity sample inlet 9 is arranged between the focusing electrode and the transmission electrode, and a supplementary gas inlet 13 is arranged between the transmission electrode and the capillary electrode; the material of the pipelines of the reagent gas inlet 12, the high-humidity sample inlet 9 and the supplementary gas inlet 13 is polytetrafluoroethylene with the inner diameter of 4 mm.
Acetone reagent gas enters a reagent ion area and is subjected to photoionization under the irradiation of a vacuum ultraviolet lamp 16, a large amount of generated acetone reagent ions enter a sample area through a focusing 18 small hole, and are subjected to proton transfer reaction with sample molecules, and then enter a mass spectrometer 22 through a metal capillary 21 for analysis.
The operation steps of the present invention are illustrated as follows:
using a 1000 mu L liquid transfer gun to transfer 2mL liquid trimethylamine and triethylamine samples 5 into a glass vial 4, then adding 100 mu L20% (w/w) sodium hydroxide solution into the glass vial 4, rapidly placing the glass vial 4 into a constant temperature water bath kettle at 60 ℃, immediately introducing 300mL/min nitrogen purge gas (8), introducing the trimethylamine and triethylamine in the water into a sample area of an atmospheric pressure photoionization source along with the purge gas, and simultaneously starting collection by a mass spectrometer with the collection time of 80 s. The flow rate of the reagent gas 14 was 100mL/min and the flow rate of the make-up gas 15 was 1200 mL/min. The high humidity sample inlet 7 tubing and ionization source temperature were maintained at 100 ℃. The sample is ionized in the ionization source and then enters the mass spectrometer through the metal capillary 21 for detection. The total time for single sample detection was about 2 min.
FIG. 2 is a mass spectrum obtained by detecting trimethylamine and triethylamine in water when acetone is used as a reagent gas.
Claims (9)
1. An atmospheric pressure photoionization source device for detection of volatile organic compounds in water, comprising: dynamic purging bubbling device (1), atmospheric pressure photoionization source (2), its characterized in that:
the dynamic purging bubbling device (1) comprises four capillary tubes (3), a glass small bottle (4), a liquid sample (5), a constant-temperature water bath kettle (6) and a bubbling bottle outlet (7); introducing purge gas (8) into four capillary tubes (3), immersing the liquid sample (5) at the bottom of the capillary tubes (3), and allowing volatile organic compounds in the liquid sample (5) to enter an atmospheric pressure photoionization source cavity (11) through a bubbling bottle outlet (7) and a heating device (10);
the dynamic purging and bubbling device (1) comprises a constant-temperature water bath kettle (6) and a small glass bottle (4), wherein the small glass bottle (4) is a container with an opening at the upper end, and a sealing cover hermetically connected with the upper opening end of the container is arranged at the upper opening end of the container; the glass small bottle (4) is arranged in the water bath of the constant temperature water bath kettle (6); the glass small bottle (4) is filled with a liquid sample (5), more than 1 capillary tube (3) extends into the liquid level of the liquid sample in the glass small bottle (4) from the upper part or the sealing cover, and a bubbling bottle outlet (7) is arranged at the upper part or the sealing cover of the glass small bottle (4); introducing a purge gas (8) into the capillary tube (3) to enter the liquid level of the liquid sample, and allowing volatile organic compounds in the liquid sample (5) to flow out through the outlet (7) of the bubbling bottle;
the atmospheric pressure photoionization source (2) comprises an ionization source cavity (11) and a capillary electrode (20);
the capillary electrode (20) is a flat plate electrode, and a metal capillary (21) penetrating through a flat plate body is arranged in the middle of the flat plate electrode to form the capillary electrode (20);
the ionization source cavity (11) is a closed container, a flat-plate-shaped repulsion electrode (17) with a through hole in the middle, a flat-plate-shaped focusing electrode (18) with a through hole in the middle and more than 1 flat-plate-shaped transmission electrode (19) with a through hole in the middle are sequentially arranged on the container from top to bottom at intervals and in parallel, a through hole is formed in the lower end face of the container below the transmission electrode (19), a capillary electrode (20) is arranged at the through hole, the lower surface of the capillary electrode (20) is hermetically connected with the bottom face of the container or the peripheral edge of the capillary electrode (20) is hermetically connected with the inner wall face of the through hole in the lower end face of the container, the upper opening end of a metal capillary (21) of the capillary electrode (20) is positioned below the; the repulsion electrode (17), the focusing electrode (18), the transmission electrode (19) and the metal capillary (21) are coaxial;
a vacuum ultraviolet lamp (16) is arranged above the repulsion electrode (17) of the container, and the light outlet of the vacuum ultraviolet lamp faces to the middle through hole of the repulsion electrode (17);
a reagent gas inlet pipe (12) is arranged on the side wall surface of the container, and the gas outlet of the reagent gas inlet pipe (12) faces to the area between the repulsion electrode (17) and the focusing electrode (18);
a high-humidity sample inlet pipe is arranged on the side wall surface of the container, and the air outlet of the high-humidity sample inlet pipe faces to the area between the focusing electrode (18) and the transmission electrode (19); the air inlet of the high-humidity sample inlet pipe is connected with the outlet (7) of the bubbling bottle;
a supplementary gas inlet pipe (13) is arranged on the side wall surface of the container, and the gas outlet of the supplementary gas inlet pipe (13) faces to the area between the transmission electrode (19) and the capillary electrode (20).
2. The atmospheric pressure photoionization source device for detection of volatile organic compounds in water according to claim 1, wherein:
an electric heating element (10) is arranged on the outer wall surface of the pipeline connecting the air inlet of the high-humidity sample inlet pipe and the outlet (7) of the bubbling bottle.
3. The atmospheric pressure photoionization source device for detection of volatile organic compounds in water according to claim 1, wherein:
the purge gas (8) and the make-up gas (15) are both dry nitrogen or air; the reagent gas (14) is one or more than two of acetone, butanone, toluene, anisole, ethanol or chlorobenzene with certain concentration;
after entering a reagent ion area, reagent gas is irradiated by a vacuum ultraviolet lamp (16) to carry out photoionization, a large number of generated reagent ions enter a sample area through a focusing (18) small hole, and are subjected to charge transfer or proton transfer reaction with sample molecules, and then enter a mass spectrometer (22) through a metal capillary (21) for analysis.
4. The atmospheric pressure photoionization source device for detection of volatile organic compounds in water according to claim 1, wherein:
the capillary (3) is a metal capillary or a PEEK capillary, more than 1 capillary has the same length, the outer diameter is 1/16 inch, and the inner diameter is 100-500 mu m; the distance between the outlet at the bottom of the capillary tube (3) and the bottom of the glass small bottle (4) is 1-3 mm.
5. The atmospheric pressure photoionization source device for detection of volatile organic compounds in water according to claim 1, wherein:
the glass small bottle (4) consists of a sealing cover (23) and a bottle body (24), the total internal volume is 10-30 mL, and the joint of the sealing cover (23) and the bottle body (24) adopts a ground design;
the material of the pipelines of the reagent gas inlet (12), the high-humidity sample inlet (9) and the supplementary gas inlet (13) is polytetrafluoroethylene.
6. The atmospheric pressure photoionization source device for detection of volatile organic compounds in water according to claim 1, wherein:
the liquid sample (5) in the glass vial (4) is immersed at the bottom of the capillary tube (3), and the volume of the liquid sample is 2-10 mL; the liquid sample can be one or more than two of domestic sewage, experimental sewage, sewage treatment plant wastewater, river water, seawater and the like;
during detection, the small glass bottle is placed in a constant-temperature water bath (6) for heat preservation, and the temperature of water (9) in the constant-temperature water bath (6) is kept between room temperature and 90 ℃.
7. The atmospheric pressure photoionization source device for detection of volatile organic compounds in water according to claim 1, wherein:
the repulsion electrode (17), the focusing electrode (18), the transmission electrode (19) and the capillary tube electrode (20) are all round stainless steel electrodes, the outer diameters of the electrodes are the same, the electrodes and the vacuum ultraviolet lamp (16) are coaxially arranged, and the distance between the electrodes is 4-10 mm; the repulsion electrode (17) is tightly attached to the edge of the light window of the vacuum ultraviolet lamp (16), and the inner diameter is 8 mm; the inner diameter of the focusing electrode (18) is 2-4 mm; the inner diameter of the transmission electrode (19) is 8-20 mm; the focus electrode (18) divides the ionization source into two parts, namely a reagent ion area (an area between the repulsion electrode (17) and the focus electrode (18)) and a sample area (an area between the focus electrode (18) and the transmission electrode (19)).
8. The atmospheric pressure photoionization source device for detection of volatile organic compounds in water according to claim 1, wherein:
resistors with the same resistance are connected between the repulsion electrode (17), the focusing electrode (18), the transmission electrode (19) and the ground, and a direct current voltage of 0-3000V is applied to the repulsion electrode (17); a DC voltage of 0-500V is applied to the capillary electrode (20).
9. The atmospheric pressure photoionization source device for detection of volatile organic compounds in water according to claim 1, wherein:
the metal capillary (21) is fixed in the center of the capillary electrode, the outer diameter is 1/16 inch, the inner diameter is 0.5-1 mm, the length of the metal capillary extending into the ionization cavity is adjustable, but the distance between the capillary electrode (20) and the transmission electrode (19) cannot be exceeded.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911225074.4A CN112908830B (en) | 2019-12-04 | 2019-12-04 | Atmospheric pressure photoionization source device for detecting volatile organic compounds in water |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911225074.4A CN112908830B (en) | 2019-12-04 | 2019-12-04 | Atmospheric pressure photoionization source device for detecting volatile organic compounds in water |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112908830A true CN112908830A (en) | 2021-06-04 |
| CN112908830B CN112908830B (en) | 2022-05-06 |
Family
ID=76104784
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911225074.4A Active CN112908830B (en) | 2019-12-04 | 2019-12-04 | Atmospheric pressure photoionization source device for detecting volatile organic compounds in water |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112908830B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080048107A1 (en) * | 2006-08-22 | 2008-02-28 | Mcewen Charles Nehemiah | Ion source for a mass spectrometer |
| CN103854952A (en) * | 2012-11-30 | 2014-06-11 | 中国科学院大连化学物理研究所 | Mass spectrum vacuum ultraviolet ionization source based on optical-window-free gas discharge lamp |
| US20150069254A1 (en) * | 2012-05-17 | 2015-03-12 | Georgia Tech Research Corporation | Sample analyzing system |
| CN105632870A (en) * | 2014-10-28 | 2016-06-01 | 中国科学院大连化学物理研究所 | Atmospheric pressure chemical ionization source for mass spectrum |
| CN106876243A (en) * | 2015-12-11 | 2017-06-20 | 中国科学院大连化学物理研究所 | One kind aids in low pressure vacuum ultraviolet light ionization source for mass spectrographic reagent molecule |
| CN108593756A (en) * | 2018-07-02 | 2018-09-28 | 中国科学技术大学 | The device for fast detecting of trace steroids in a kind of water body |
-
2019
- 2019-12-04 CN CN201911225074.4A patent/CN112908830B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080048107A1 (en) * | 2006-08-22 | 2008-02-28 | Mcewen Charles Nehemiah | Ion source for a mass spectrometer |
| US20150069254A1 (en) * | 2012-05-17 | 2015-03-12 | Georgia Tech Research Corporation | Sample analyzing system |
| CN103854952A (en) * | 2012-11-30 | 2014-06-11 | 中国科学院大连化学物理研究所 | Mass spectrum vacuum ultraviolet ionization source based on optical-window-free gas discharge lamp |
| CN105632870A (en) * | 2014-10-28 | 2016-06-01 | 中国科学院大连化学物理研究所 | Atmospheric pressure chemical ionization source for mass spectrum |
| CN106876243A (en) * | 2015-12-11 | 2017-06-20 | 中国科学院大连化学物理研究所 | One kind aids in low pressure vacuum ultraviolet light ionization source for mass spectrographic reagent molecule |
| CN108593756A (en) * | 2018-07-02 | 2018-09-28 | 中国科学技术大学 | The device for fast detecting of trace steroids in a kind of water body |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112908830B (en) | 2022-05-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN201993338U (en) | Sweeping type film inlet-cushion chamber device with fast online enrichment of mass spectra | |
| CN109755097A (en) | A kind of quadrupole mass spectrometer and its application method | |
| CN106373855B (en) | The mass spectrometric apparatus of organic pollution in a kind of quick analysis gas or liquid | |
| CN108051496A (en) | The method detected in real time using Excited state proton trans fer mass spectrograph progress water body Taste and odor compounds | |
| CN102103124A (en) | Method for quickly analyzing organic pollutant in liquid on line by using micro mass spectrometer | |
| Wu et al. | An in-source helical membrane inlet single photon ionization time-of-flight mass spectrometer for automatic monitoring of trace VOCs in water | |
| CN108593756B (en) | Quick detection device of trace steroid in water | |
| Wu et al. | Rapid and highly sensitive measurement of trimethylamine in seawater using dynamic purge-release and dopant-assisted atmospheric pressure photoionization mass spectrometry | |
| CN107561180A (en) | A kind of method that volatile organic matter in water is detected based on counter-infiltration | |
| CN112908830B (en) | Atmospheric pressure photoionization source device for detecting volatile organic compounds in water | |
| CN113834884A (en) | Ozone layer consumables on-line monitoring system | |
| CN113607800A (en) | Rapid mass spectrometry detection device and detection method for detecting rubber content in plant | |
| CN112908829B (en) | Source-inner membrane sample injection radio frequency enhanced chemical ionization source | |
| Shoemaker et al. | Determination of polar volatile organic compounds in water by membrane permeate and trap GC-MS | |
| CN108088891A (en) | A kind of ion mobility spectrometry and operating method for being disposed vertically VUV radio-frequency lamps | |
| CN111239277B (en) | Method and kit for determining N-dimethyl nitrosamine in water and application | |
| CN113607852B (en) | Method for measuring turpentine in soil | |
| Xie et al. | A novel method for the detection of MTBE: ion mobility spectrometry coupled to multi capillary column | |
| CN213875525U (en) | Ion mobility spectrometry's pre-enrichment device | |
| CN114002306A (en) | Membrane sample injection structure for extracting volatile organic compounds in water through bubble enrichment | |
| Hashimoto et al. | An automated purge and trap gas chromatography‐mass spectrometry system for the sensitive shipboard analysis of volatile organic compounds in seawater | |
| CN205280680U (en) | Survey system of trace alkyl mercury | |
| CN113390998A (en) | Method for detecting N-nitrosodimethylamine in drinking water | |
| CN111521523A (en) | Method for rapidly detecting migration of chemical substances in protective coating to wading pipe | |
| CN111060632A (en) | Method for detecting tetraethyl lead in water |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |