CN202974961U - Photoionization detector - Google Patents
Photoionization detector Download PDFInfo
- Publication number
- CN202974961U CN202974961U CN 201220664573 CN201220664573U CN202974961U CN 202974961 U CN202974961 U CN 202974961U CN 201220664573 CN201220664573 CN 201220664573 CN 201220664573 U CN201220664573 U CN 201220664573U CN 202974961 U CN202974961 U CN 202974961U
- Authority
- CN
- China
- Prior art keywords
- ionization chamber
- electrode
- photoionization detector
- polarized
- uviol lamp
- 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.)
- Expired - Fee Related
Links
Images
Landscapes
- Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
Abstract
The utility model discloses a photoionization detector which consists of a polarized electrode, a reception electrode, an ionization chamber, an ultraviolet lamp and a heating device, wherein the ionization chamber is a cavity formed by a cylindrical polarized electrode in an enclosing manner, and a needle-shaped receiving electrode is arranged inside the ionization chamber; a polarized electric field is formed between the receiving electrode and the polarized electrode; the ultraviolet lamp is positioned at one end of the ionization chamber and is coaxial with the ionization chamber; two ends of the ionization chamber are provided with an ionization chamber air inlet and an ionization chamber air outlet; a heating rod and a temperature sensor are arranged on a shell; a sample to be tested enters from the ionization chamber air inlet at constant temperature, ultraviolet light emitted by the ultraviolet lamp directly irradiates the ionization chamber, the sample to be tested is ionized, and ions are moved to the receiving electrode to form an electric signal under the action of the polarized electric field; and an excessive sample flows out from the ionization chamber air outlet. The photoionization detector is high in sensitivity, fast in response, high in stability, simple in structure and small in size and is suitable for a portable instrument, and the positive and negative ions can be detected.
Description
Technical field
The utility model relates to a kind of photoionization detector, a kind of detecting device that adopts the ultraviolet light ionization material and detect.
Background technology
Photoionization detector (photo ionization detector, PID) is a kind of gas chromatography detector commonly used, utilizes the ionising effects of light to realize ionization.Photoionization detector has high sensitivity, the range of linearity wide (concentration range generally at 4 ~ 5 more than the order of magnitude), and selectivity is good, the advantages such as applied range.Compare with traditional detecting device, it also has highly sensitive, and is portable, fast response time, but the advantages such as continuous detecting.Be mainly used in environmental protection, field of petrochemical industry.Detectable material comprises aromatics, alcohols, aldehydes, ketone, amine, halogenated hydrocarbon, sulfo-hydro carbons, unsaturated hydro carbons and carbon-free inorganic gas (ammonia, arsenic, selenium), bromine and iodine class etc.
Its principle of work is that organism to be measured produces under the direct irradiation of ultraviolet light at the uviol lamp that specific ionization energy (as 10.6eV) arranged (UV), generation photoionization reaction, organic molecule is ionized into positive ion and electronics, under the effect of polarized electric field, charged ion moves to collector, and the detected low current signal that produces.Draw the size of test substance concentration by the size that detects the low current signal that ion forms.
According to principle of work, ionization energy is to determine that can optic ionized sensor detect the key factor of certain compound.Enough short at the ionization chamber light path, enough in low situation, measured matter concentration is just linear with the photoionization electric current for sample concentration, and namely the optic ionized sensor signal is directly proportional to test substance concentration.Should make every effort to satisfy for the design of ionization chamber the requirement that detects index and sensitivity.So be limited to the purpose photoionization detector with high sensitivity, the low detection, should have shorter ionization chamber.
Polarized electric field in ionization chamber has vital impact to the sensitivity of photoionization detector equally.Reasonably polarized electric field makes the sample ions that is ionized arrive easily receiving pole and produces electric signal.In the situation that there is no polarized electric field, the sample ions that is ionized also can be received the utmost point and detect under the drive of air-flow, have this process that makes under the condition of polarized electric field to be more prone to, make detectability improve not only one or two the order of magnitude.At present domestic patent is generally formed by two special plate electrodes about the polarized electric field of photoionization detector inside, that is, and and receiving pole of two polarized electrodes, three electrodes.And in this patent wherein a slice polarized electrode and receiving pole shared, therefore namely two electrodes have been realized simplifying the structure the function of three electrodes.
Generally use under the environment higher than room temperature in order to eliminate fast sample residual light ionization detector.But photoionization detector is also more responsive to temperature, and in general temperature raises, and the light intensity decreasing of uviol lamp, the light transmission rate of small wavelength also descend rapidly, make detectability increase.The change temperature is also larger on the baseline impact of photoionization detector, and rising temperature baseline raises.Special heating unit and temperature controller coupling can make photoionization detector be operated under a certain stationary temperature condition in this patent for this reason.
The utility model content
The purpose of this utility model is to provide highly sensitive, and response is rapid, good stability, and simple in structure, volume is little, a kind of photoionization detector that negative ions can detect.
For achieving the above object, the technical solution of the utility model is: a kind of photoionization detector comprises polarized electrode, receiving electrode, ionization chamber, uviol lamp;
Polarized electrode is cylindrical shape, and the central axis in the cylindrical shape polarized electrode is provided with a needle electrode, and as receiving electrode, the inner cylindrical chamber of polarized electrode consists of ionization chamber; Receiving electrode is coaxial with polarized electrode, is positioned on the central shaft of ionization chamber; The polarized electrode outside is enclosed with a housing;
Uviol lamp is arranged at ionization chamber one end, the ultraviolet light light path that uviol lamp sends and the spigot shaft coaxle of ionization chamber, and UV-irradiation is on the central shaft of ionization chamber;
Be provided with the ionization chamber gas outlet in the sidewall near the polarized electrode of uviol lamp, be provided with the ionization chamber air intake opening on away from the sidewall of the polarized electrode of uviol lamp or away from the housing of uviol lamp.
Be provided with heating rod and temperature sensor in the housing near the ionization chamber position; They are used for controlling the working temperature of photoionization detector.
Uviol lamp is connected with housing by hold-down nut, is provided with the O-ring seal for the sealing ionization chamber between the wall outside the uviol lamp light-emitting window and housing.
Polarized electrode is cylindrical shape, and the internal diameter of cylinder is 2.5-5mm, and length is 2-5mm, thereby guarantees the enough little dead space that reduces of ionization chamber.
The diameter of receiving electrode is little, generally at 0.1-0.5mm, reduces the background signal that uviol lamp produces its irradiation; Between the syringe needle of receiving electrode and uviol lamp exiting surface, distance is about 0.5mm; The receiving electrode surface gold-plating.
Polarized electrode is with polarizing voltage, and receiving electrode is connected with the signal amplifier signal; Polarized electrode band positive polarization voltage during detection of positive ions, polarized electrode band negative polarization voltage when detecting negative ion.
Uviol lamp is that fenestrate lamp is also or for windowless lamp; It is the direct current lamp or is AC Lamp.
The maximum heating temperature of photoionization detector does not surpass 350 degree.
Air intake opening and gas outlet communicate with ionization chamber, are the micropore of aperture 0.1-2mm; Be the impact of less air-flow on detecting device, the work maximum airflow does not surpass 500ml/min.
The utility model photoionization detector is used very extensive, and the detecting device that both can be used as gas chromatography uses, and detects various organic compounds; Also can be used as the detecting device of the hazardous chemical of environmental protection industry (epi), be applicable in portable instrument.This photoionization detector is highly sensitive, and response is rapid, good stability, and negative ions can detect, and the detectability concentration that detects the organic compounds such as acetone, benzene is the ppb level.
Description of drawings
Below in conjunction with accompanying drawing, the utility model is described in further detail:
The structural representation of Fig. 1 the utility model photoionization detector.
Fig. 2 the utility model photoionization detector is surveyed the signal of 50ppb acetone.
Embodiment
The photoionization detector structure as shown in Figure 1, comprise polarized electrode 10, accept electrode 1, ionization chamber 2, uviol lamp 7(to be to have the optical window uviol lamp as example), the heating arrangement that forms of housing 12 and heating rod 3 and temperature sensor 8.
Receiving electrode 1 syringe needle and uviol lamp optical window 11 distances are about 0.5mm and are benefit.During normal operation, polarized electrode 10 is with polarizing voltage, and receiving electrode 1 is connected with amplifier signal.Polarized electrode 10 band positive polarization voltages during detection of positive ions, polarized electrode 10 band negative polarization voltages when detecting negative ion.
Be provided with ionization chamber gas outlet 4 in the sidewall near the polarized electrode 10 of uviol lamp 7, be provided with ionization chamber air intake opening 9 on away from the sidewall of the polarized electrode 10 of uviol lamp 7 or away from the housing 12 of uviol lamp 7.
Be provided with heating rod 3 and temperature sensor 8 in housing 12 near ionization chamber 2 positions; They are used for controlling the working temperature of photoionization detector.
The principle of work of this photoionization detector is: photoionization detector at a certain temperature, detected sample enters ionization chamber 2 from ionization chamber air intake opening 9 and be ionized into negative ions under the UV-irradiation that uviol lamp 7 sends.The detection of positive ions signal is that 10 polarity with voltage of polarized electrode are different from the difference of negative ion signal, and the voltage of positive ion polarizations electrode 10 is positive polarization voltage.The voltage of negative ion polarizations electrode 10 is negative polarization voltage.As: detect the negative ion signal, polarized electrode 10 is with negative polarization voltage, form polarized electric field like this between polarized electrode 10 and receiving electrode 1, negative ions is under the effect of polarized electric field, positive ion moves on polarized electrode 10 rapidly, negative ion moves to receiving electrode 1, and finally they are all beaten on electrode, forms little electric current.Photoionization detector signal after the little electric current that produces on receiving electrode 1 amplifies through amplifier.The unnecessary sample that there is no ionization 4 flows out from the ionization chamber gas outlet under the drive of carrier gas.
This photoionization detector is applied on quick gas chromatography, sees Fig. 2.The photoionization detector temperature is 60 ℃, the negative ion signal of the 50ppb acetone of surveying.Signal response is rapid, and symmetry is good.
Claims (9)
1. a photoionization detector, comprise polarized electrode, receiving electrode, ionization chamber, uviol lamp; It is characterized in that:
Polarized electrode is cylindrical shape, and the central axis in the cylindrical shape polarized electrode is provided with a needle electrode, and as receiving electrode, the inner cylindrical chamber of polarized electrode consists of ionization chamber; Receiving electrode is coaxial with polarized electrode, is positioned on the central shaft of ionization chamber; The polarized electrode outside is enclosed with a housing;
Uviol lamp is arranged at ionization chamber one end, the ultraviolet light light path that uviol lamp sends and the spigot shaft coaxle of ionization chamber, and UV-irradiation is on the central shaft of ionization chamber;
Be provided with the ionization chamber gas outlet in the sidewall near the polarized electrode of uviol lamp, be provided with the ionization chamber air intake opening on away from the sidewall of the polarized electrode of uviol lamp or away from the housing of uviol lamp.
2. photoionization detector as claimed in claim 1 is characterized in that:
Be provided with heating rod and temperature sensor in the housing near the ionization chamber position.
3. photoionization detector as claimed in claim 1 is characterized in that:
Uviol lamp is connected with housing by hold-down nut, is provided with the O-ring seal for the sealing ionization chamber between the wall outside the uviol lamp light-emitting window and housing.
4. photoionization detector as claimed in claim 1 is characterized in that:
Polarized electrode is cylindrical shape, and the internal diameter of cylinder is 2.5-5mm, and length is 2-5mm.
5. photoionization detector as claimed in claim 1 is characterized in that:
The diameter of receiving electrode is little, is 0.1-0.5mm; Between the syringe needle of receiving electrode and uviol lamp exiting surface, distance is 0.5mm; The receiving electrode surface gold-plating.
6. photoionization detector as claimed in claim 1 is characterized in that:
Polarized electrode is with polarizing voltage, and receiving electrode is connected with the signal amplifier signal; Polarized electrode band positive polarization voltage during detection of positive ions, polarized electrode band negative polarization voltage when detecting negative ion.
7. photoionization detector as claimed in claim 1 is characterized in that:
Uviol lamp is that fenestrate lamp is also or for windowless lamp; It is the direct current lamp or is AC Lamp.
8. photoionization detector as claimed in claim 1 is characterized in that:
The maximum heating temperature of photoionization detector does not surpass 350 degree.
9. photoionization detector as claimed in claim 1 is characterized in that:
Air intake opening and gas outlet communicate with ionization chamber, are the micropore of aperture 0.1-2mm; Be the impact of less air-flow on detecting device, the work maximum airflow does not surpass 500ml/min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220664573 CN202974961U (en) | 2012-12-05 | 2012-12-05 | Photoionization detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220664573 CN202974961U (en) | 2012-12-05 | 2012-12-05 | Photoionization detector |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202974961U true CN202974961U (en) | 2013-06-05 |
Family
ID=48516020
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201220664573 Expired - Fee Related CN202974961U (en) | 2012-12-05 | 2012-12-05 | Photoionization detector |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN202974961U (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104535643A (en) * | 2014-12-16 | 2015-04-22 | 中国科学院长春光学精密机械与物理研究所 | Ion generating and extracting device and control method thereof |
| CN104597477A (en) * | 2013-10-31 | 2015-05-06 | 中国科学院大连化学物理研究所 | Photoelectronic imaging device for researching anion system |
| CN105158325A (en) * | 2015-07-30 | 2015-12-16 | 安徽中杰信息科技有限公司 | Photoionization detector |
| CN108614029A (en) * | 2018-05-12 | 2018-10-02 | 重庆邮电大学 | High-sensitivity miniature optic ionized sensor |
| CN109884165A (en) * | 2019-03-11 | 2019-06-14 | 重庆邮电大学 | Photoionization detector ionisation chamber and photoionization detector |
| CN110441385A (en) * | 2019-08-14 | 2019-11-12 | 中国电子科技集团公司第四十九研究所 | Miniature ionization chamber and miniature ultraviolet source integral piece for miniature optical ionization gas sensor |
| CN110554126A (en) * | 2019-10-21 | 2019-12-10 | 江苏天瑞仪器股份有限公司 | electron capture detector and gas phase device |
| CN111983008A (en) * | 2019-05-23 | 2020-11-24 | 中国科学院合肥物质科学研究院 | Small photoionization detector and detection method thereof |
| CN114534982A (en) * | 2020-11-26 | 2022-05-27 | 中国科学院大连化学物理研究所 | Auxiliary photoionization source for in-situ ultrasonic atomization reagent |
-
2012
- 2012-12-05 CN CN 201220664573 patent/CN202974961U/en not_active Expired - Fee Related
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104597477A (en) * | 2013-10-31 | 2015-05-06 | 中国科学院大连化学物理研究所 | Photoelectronic imaging device for researching anion system |
| CN104597477B (en) * | 2013-10-31 | 2017-06-30 | 中国科学院大连化学物理研究所 | A kind of photoelectronic imaging device for studying anion system |
| CN104535643B (en) * | 2014-12-16 | 2017-04-05 | 中国科学院长春光学精密机械与物理研究所 | There is ejector and its control method in a kind of ion |
| CN104535643A (en) * | 2014-12-16 | 2015-04-22 | 中国科学院长春光学精密机械与物理研究所 | Ion generating and extracting device and control method thereof |
| CN105158325A (en) * | 2015-07-30 | 2015-12-16 | 安徽中杰信息科技有限公司 | Photoionization detector |
| CN108614029B (en) * | 2018-05-12 | 2024-05-28 | 重庆邮电大学 | High-sensitivity miniature photoionization sensor |
| CN108614029A (en) * | 2018-05-12 | 2018-10-02 | 重庆邮电大学 | High-sensitivity miniature optic ionized sensor |
| CN109884165A (en) * | 2019-03-11 | 2019-06-14 | 重庆邮电大学 | Photoionization detector ionisation chamber and photoionization detector |
| CN109884165B (en) * | 2019-03-11 | 2024-05-28 | 重庆邮电大学 | Ionization chamber of photoionization detector and photoionization detector |
| CN111983008A (en) * | 2019-05-23 | 2020-11-24 | 中国科学院合肥物质科学研究院 | Small photoionization detector and detection method thereof |
| CN110441385A (en) * | 2019-08-14 | 2019-11-12 | 中国电子科技集团公司第四十九研究所 | Miniature ionization chamber and miniature ultraviolet source integral piece for miniature optical ionization gas sensor |
| CN110554126A (en) * | 2019-10-21 | 2019-12-10 | 江苏天瑞仪器股份有限公司 | electron capture detector and gas phase device |
| CN114534982A (en) * | 2020-11-26 | 2022-05-27 | 中国科学院大连化学物理研究所 | Auxiliary photoionization source for in-situ ultrasonic atomization reagent |
| CN114534982B (en) * | 2020-11-26 | 2023-03-14 | 中国科学院大连化学物理研究所 | Auxiliary photoionization source for in-situ ultrasonic atomization reagent |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN202974961U (en) | Photoionization detector | |
| CN202003947U (en) | Mass spectrum sample introduction device capable of switching between capillary sample introduction and membrane sample introduction | |
| CN102128890B (en) | High-sensitivity testing method capable of simultaneously implementing measurement of multiple negative ions | |
| CN102866224B (en) | Gas chromatographic detection method for determining carbon-containing compound based on carbon atomic emission spectroscopy | |
| CN203895411U (en) | Film gathering and sampling device of mass spectrometer | |
| CN206420776U (en) | Gas concentration monitors sensing device | |
| CN104713945A (en) | Method for detecting explosive peroxide TATP | |
| CN102565019A (en) | Mini-type portable type TNT (2,4,6-trinitrotoluene) explosive detector | |
| CN201514403U (en) | Helium photoionization gas chromatography detector | |
| CN103776818A (en) | Glow discharge-based plasma generator and spectrum detection system formed by same | |
| CN204028089U (en) | Environment foul gas detector | |
| CN103811265A (en) | Doping agent auxiliary ionization source and application thereof in ion mobility spectrometry | |
| CN203658269U (en) | Plasma exciting spectrum detection system based on glow discharge | |
| CN108088891A (en) | A kind of ion mobility spectrometry and operating method for being disposed vertically VUV radio-frequency lamps | |
| CN105319284A (en) | Gas-chromatography ion-mobility-spectrometry combined use method | |
| CN103776893B (en) | A kind of dielectric barrier discharge ionization source ionic migration spectrometer | |
| CN105632865B (en) | A kind of on-radiation transference tube | |
| CN204514858U (en) | A kind of NMHC gas detecting instrument | |
| CN112834603B (en) | Combined efficient thermal desorption device | |
| CN103854954A (en) | Thermal desorption membrane inlet high field asymmetry waveform ion migration spectrometer | |
| CN205194655U (en) | Corona discharge ionization trigger device | |
| CN104251856A (en) | Peroxide gas sensor and preparation method thereof, and peroxide gas detection method | |
| CN203300594U (en) | Microwave plasma normal pressure desorption ion source and ion source device constituted thereby | |
| CN104677438B (en) | A kind of Ion transfer type gas flowmeter | |
| CN105158325A (en) | Photoionization detector |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20130605 Termination date: 20181205 |