US3681598A - Sampling device for mass spectrometric analysis - Google Patents

Sampling device for mass spectrometric analysis Download PDF

Info

Publication number
US3681598A
US3681598A US803635A US3681598DA US3681598A US 3681598 A US3681598 A US 3681598A US 803635 A US803635 A US 803635A US 3681598D A US3681598D A US 3681598DA US 3681598 A US3681598 A US 3681598A
Authority
US
United States
Prior art keywords
sample
tubular member
bore
vacuum source
vaporizing
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 - Lifetime
Application number
US803635A
Inventor
Warren M Thurston
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Atomic Energy of Canada Ltd AECL
Original Assignee
Atomic Energy of Canada Ltd AECL
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Atomic Energy of Canada Ltd AECL filed Critical Atomic Energy of Canada Ltd AECL
Application granted granted Critical
Publication of US3681598A publication Critical patent/US3681598A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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
    • H01J49/04—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
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
    • G03G5/10—Bases for charge-receiving or other layers
    • 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
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N1/00—Sampling; Preparing specimens for investigation
    • G01N1/02—Devices for withdrawing samples
    • G01N1/22—Devices for withdrawing samples in the gaseous state

Definitions

  • the device facilitates the automated analysis of a large [58] Field of Search ..250/4l.9 S, 73/4215, number of samples 4 Claims, 4 Drawing Figures SAMPLING DEVICE FOR MASS SPECTROMETRIC ANALYSIS
  • This invention relates to a sample vaporizing device, and in particular to a sample vaporizing device to facilitate automated mass spectrometric analysis of water for the determination of the deuterium content thereof.
  • the mass spectrometric analysis of samples was performed by introducing a sample into a sealed container, vaporizing the entire sample by heating, introducing the vapor into a spectrometer and subsequently purging the container and spectrometer before the introduction of another sample.
  • a major difficulty in automating mass spectrometric analysis has been the problem of inserting a representative sample in the spectrometer. For analysis the sample must be in the vapor state. Because isotopic fractionation occurs at a liquid-vapor interface or water evaporator, it has been necessary, using normal procedures, to totally evaporate a sample of water before introduction into a spectrometer. The automation of such a procedure would require eleborate equipment.
  • the present device facilitates an automated procedure for analyzing a large number of samples rapidly.
  • the invention consists of an elongated tubular member having an inlet portion with a reduced bore, a central evaporation portion and an outlet portion for connection with a vacuum source and an analyzing device, said central portion having a bore of increasing cross-sectional area from the inlet portion to the outlet portion.
  • the inlet portion will have a bore diameter of less than 60.microns and preferably from 20 to 30 microns.
  • the invention also consists of an apparatus comprising a tubular member having an inlet portion with a reduced bore, a central evaporation portion having a bore increasing cross-sectional area from the inlet portion to an outlet portion, connected to first and second passage means, said first passage means connected to a sample analyzing device and said second passage means connected to a vacuum source, and valve means releasably blocking said second passage.
  • the apparatus includes means to move sample containers successively into position relative to said tubular member, means to move said tubular member in and out of contact with the sample containers, and means to shutoff and open said valve means in accordance with the position of said tubular member.
  • the invention also consists of a method of vaporizing a liquid sample for analysis using a vaporizing device comprising a reduced inlet portion, a tapered vaporizing portion and an outlet portion connected with a vacuum source and an analyzing device, comprising the steps of drawing the sample into the vaporizing device with the vacuum source until equilibrium in the tapered evaporation portion has been established, shutting off the vacuum source to allow the vaporized sample to enter the analyzing device, performing the analysis, and applying the vacuum to purge the analyzing device.
  • the method comprises the further step of removing the inlet portion from the sample and moving, a second sample into the position, relative to the vaporizing device, occupied by the first mentioned sample.
  • the vacuum source preferably provides a pressure between 0.01 torr and 7 torr.
  • the meniscus in the evaporation portion is kept below 1 mm in diameter.
  • the above method in particular is for samples of water containing deuterium.
  • FIG. 1 is an enlarged side view of the sample vaporizing device.
  • FIGS. 2 to 4 are schematic views of the apparatus at three stages of operation.
  • the vaporizing device comprises a tubular member 1 having an inlet portion 2 with a reduced'bore 5, a central evaporationportion 3 with a bore 6 of increasing cross-sectional area from the inlet portion 2 to an outlet portion 4.
  • the outlet portion 4 is connected to an analyzing device 10 and a vacuum source 11.
  • the vacuum source is selectively isolated by valve means 12.
  • the operation of the vaporizing device is as follows.
  • the liquid sample is drawn into'the tubular member by v the vacuum pumpthrough the restricted bore 5 into the tapered evaporation portion 3.
  • the sample will rise through the section of increasing cross-sectional area 6 to a level 8 at which the sample is evaporated at a rate equal to the liquid inflow. Thereafter the liquid level will remain constant. 7
  • the apparatus used for automated analysis is shown schematically in FIGS. 2 to 4.
  • the tubular member 1 is connected to a vacuum source 11 and a mass spectrometer, chromatograph, or other analyzing device 10.
  • the vacuum source 11 is selectively isolated from the mass spectrometer l0 and the tubular member 1 by a valve 12.
  • the mass spectrometer 10 may be connected directly to the tubular member 1.
  • the apparatus includes means for moving the tubular member 1 up and down in accordance with the motion of a series of sample containers, e.g., l5 and 16 moved successively into position under the device 1. Means are also provided to shutoff and open the valve 12 in accordance with the motions of the sample containers and the tubular member 1, and required sample pressure in the analyzing device.
  • the tubular member 1 is raisedfrom the sample and the valvel2 isopened.
  • the spectrometer and tubular member 1 are pumped out and vacuum dried.
  • a new sample 16 is moved into position to replace sample 15, and the cycle repeated, orjthe cycle may be repeated using the same samplgas required.
  • the containers may remain stationary and the tubular member moved from one container to another.
  • the preferred inlet bore 5 diameter is to 30 microns. Below this range the inlet becomes increasingly susceptible to clogging.
  • the bore 5 may be increased above the preferred range if the capillary length is increased accordingly.
  • the diameter of the meniscus 8 in the evaporation position 6 is preferably kept at 1mm or less.
  • the upper evaporating layer of the A suitable pressure range at the outlet for the device described above is 0.01 torr to 7-torr.
  • sample is The precision obtainable 1 for a, deuterium.
  • hydrogen concentration-ofl50 X l0" is; 0.lppm, which is equal to 'or better than that attained with manual operation of the same analysis.
  • sample containerlS and l6 may be i made of any material, a'container of a material with which water formsaconvex meniscus is preferable.
  • a method similar to that described may facilitate the. analysis of gas samples, in a pipe or the like.
  • the tubular member'does'no't vaporize the sample but otherwise maintains the same function of dosing the spectrometer.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
  • Sampling And Sample Adjustment (AREA)
  • Electron Tubes For Measurement (AREA)
  • Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)

Abstract

A device for vaporizing a liquid for analysis, consisting of a tubular member having an inlet with a reduced bore and a tapered evaporation portion, and is connected with a vacuum source and mass spectrometer. The device facilitates the automated analysis of a large number of samples.

Description

United States Patent Thurston [451 Aug. 1, 1972 1541 SAMPLING DEVICE on MASS [56] mam cm T T S ASIALYSIS I UNITED STATES PATENTS [72] Deep 2,922,306 1/1960 Crable 2so/41.9 [73] Assignee: Atomic Energy of Canada Limited, Primary Examiner-James W. Lawrence Ottawa, Ontario, Canada Assistant Examiner-C. E. Church 22 Filed: March 3, 1969 3' 9 [21 Appl. No.2 803,635 v TRA T I I A device for vaporizing a liquid for analysis, consisting 52 us. c1. ..2s0/41.9 s 73/425.6 122/4' tubular member having inlet with a reduced 7 250743 5 bore and a tapered evaporation portion, and is con- [511 Int. Cl j 39/34 B01 d 5/44 nected with a vacuum source and mass spectrometer. The device facilitates the automated analysis of a large [58] Field of Search ..250/4l.9 S, 73/4215, number of samples 4 Claims, 4 Drawing Figures SAMPLING DEVICE FOR MASS SPECTROMETRIC ANALYSIS This invention relates to a sample vaporizing device, and in particular to a sample vaporizing device to facilitate automated mass spectrometric analysis of water for the determination of the deuterium content thereof.
Prior to the present invention the mass spectrometric analysis of samples was performed by introducing a sample into a sealed container, vaporizing the entire sample by heating, introducing the vapor into a spectrometer and subsequently purging the container and spectrometer before the introduction of another sample.
A major difficulty in automating mass spectrometric analysis has been the problem of inserting a representative sample in the spectrometer. For analysis the sample must be in the vapor state. Because isotopic fractionation occurs at a liquid-vapor interface or water evaporator, it has been necessary, using normal procedures, to totally evaporate a sample of water before introduction into a spectrometer. The automation of such a procedure would require eleborate equipment.
In the production of heavy water it is advantageous to analyze a large number of water sources to determine the deuterium content. The present device facilitates an automated procedure for analyzing a large number of samples rapidly.
The invention consists of an elongated tubular member having an inlet portion with a reduced bore, a central evaporation portion and an outlet portion for connection with a vacuum source and an analyzing device, said central portion having a bore of increasing cross-sectional area from the inlet portion to the outlet portion.
For vaporizing water the inlet portion will have a bore diameter of less than 60.microns and preferably from 20 to 30 microns.
The invention also consists of an apparatus comprising a tubular member having an inlet portion with a reduced bore, a central evaporation portion having a bore increasing cross-sectional area from the inlet portion to an outlet portion, connected to first and second passage means, said first passage means connected to a sample analyzing device and said second passage means connected to a vacuum source, and valve means releasably blocking said second passage.
In addition the apparatus includes means to move sample containers successively into position relative to said tubular member, means to move said tubular member in and out of contact with the sample containers, and means to shutoff and open said valve means in accordance with the position of said tubular member.
The invention also consists of a method of vaporizing a liquid sample for analysis using a vaporizing device comprising a reduced inlet portion, a tapered vaporizing portion and an outlet portion connected with a vacuum source and an analyzing device, comprising the steps of drawing the sample into the vaporizing device with the vacuum source until equilibrium in the tapered evaporation portion has been established, shutting off the vacuum source to allow the vaporized sample to enter the analyzing device, performing the analysis, and applying the vacuum to purge the analyzing device.
Preferably the method comprises the further step of removing the inlet portion from the sample and moving, a second sample into the position, relative to the vaporizing device, occupied by the first mentioned sample.
The vacuum source preferably provides a pressure between 0.01 torr and 7 torr.
Preferably the meniscus in the evaporation portion is kept below 1 mm in diameter.
The above method in particular is for samples of water containing deuterium.
The invention will now be described by way of example, with reference to the accompanying drawings in which:
FIG. 1 is an enlarged side view of the sample vaporizing device.
FIGS. 2 to 4 are schematic views of the apparatus at three stages of operation.
Referring to FIG. I, the vaporizing device comprises a tubular member 1 having an inlet portion 2 with a reduced'bore 5, a central evaporationportion 3 with a bore 6 of increasing cross-sectional area from the inlet portion 2 to an outlet portion 4.'
Referring to FIGS. 1 to 4, the outlet portion 4 is connected to an analyzing device 10 and a vacuum source 11. The vacuum source is selectively isolated by valve means 12. I
The operation of the vaporizing device is as follows.
The liquid sample is drawn into'the tubular member by v the vacuum pumpthrough the restricted bore 5 into the tapered evaporation portion 3. The sample will rise through the section of increasing cross-sectional area 6 to a level 8 at which the sample is evaporated at a rate equal to the liquid inflow. Thereafter the liquid level will remain constant. 7
-At the surface where evaporation is taking place, in the case of water containing deuterium, a shallow isotopic gradient will be formed because of the ,difference in vapor pressures of water and deuterium. The first portion of the sample evaporated will be depicted in deuterium and hence the surface layer of liquid will be enriched in deuterium. Shortly thereafter isotopic equilibrium is set up in which the deuterium concentration of the vapor leaving the slightly enriched surface is equal to'the deuterium concentration of the liquid entering the sample tube. The equilibrium time for the apparatus used was less than 2 seconds. The vapor produced during this time is discarded.
The apparatus used for automated analysis is shown schematically in FIGS. 2 to 4. The tubular member 1 is connected to a vacuum source 11 and a mass spectrometer, chromatograph, or other analyzing device 10. The vacuum source 11 is selectively isolated from the mass spectrometer l0 and the tubular member 1 by a valve 12. The mass spectrometer 10 may be connected directly to the tubular member 1. The apparatusincludes means for moving the tubular member 1 up and down in accordance with the motion of a series of sample containers, e.g., l5 and 16 moved successively into position under the device 1. Means are also provided to shutoff and open the valve 12 in accordance with the motions of the sample containers and the tubular member 1, and required sample pressure in the analyzing device. v
The operation of the apparatus will now be described with reference to FIGS. 2 to 4.
. disrupted causing spurious results.
' discarded.
1 In FIG. 3 equilibriumohas beenfes tablished the valve l2 is close'd and the spectrometer is being-dosed with the sample. The analysis as required is then performed.
- In FIG. 4 the analysis has been completed, thetubular member 1 is raisedfrom the sample and the valvel2 isopened. The spectrometer and tubular member 1 are pumped out and vacuum dried. A new sample 16 is moved into position to replace sample 15, and the cycle repeated, orjthe cycle may be repeated using the same samplgas required. Alternatively the containers may remain stationary and the tubular member moved from one container to another.
a The manner in which the tubular member was made willnow be described. Almm bore glass capillary was pre-collapsed while heating with a flame. The bore was reduced until almost invisible, approximately 0.1mm, while maintaining the outside of the capillary at the same diameter. The capillary was then pulled to several feet to reduce the bore further and broken off at the point which has the desired bore.
Suitable dimensions for the tubular member were obtained by trial and error. The preferred inlet bore 5 diameter is to 30 microns. Below this range the inlet becomes increasingly susceptible to clogging.-
- The bore 5 may be increased above the preferred range if the capillary length is increased accordingly.
However, the increase in length increases the equilibrium time as it increases the time required for the sample a to be drawn up the additional length of tube.
The diameter of the meniscus 8 in the evaporation position 6 is preferably kept at 1mm or less. Above l'mm the upper evaporating layer of the A suitable pressure range at the outlet for the device described above is 0.01 torr to 7-torr.
sample is The precision obtainable 1 for a, deuterium. to
hydrogen concentration-ofl50 X l0" is; 0.lppm, which is equal to 'or better than that attained with manual operation of the same analysis.
1 Although the sample containerlS and l6 may be i made of any material, a'container of a material with which water formsaconvex meniscus is preferable. An
example of such a material is rxr'vlytetrat'louroethylene. Any foreign particles-which enterthe container will tend to move to the outside and reduce .the possibility of clogging the tubular memberinlet 5 when drawing the sample.
A method similar to that described may facilitate the. analysis of gas samples, in a pipe or the like. In this case the tubular member'does'no't vaporize the sample but otherwise maintains the same function of dosing the spectrometer.
it is to be understood limited to the analysis of water. The present method I may be usedtoprovide vaporized samples of a variety of liquids. Such other liquids would necessitate establishing suitable operating conditions, i.e. tubular member dimensions and vacuum level. v
at-isclaimedi .-An apparatus or vaporizing liquid-samples-comprising a tubular member having an inlet portion with a I reduced bore, a central evaporation portion having a bore of increasing cross-sectional area from the inlet portion to an outlet portion, said outlet portion con-: nected to first and secondpassage means, said first" passage means connected to a sample analyzing device and said second passage means connected to a vacuum source, and valve means releasably blocking said second passage.
2. The apparatus of claim 1 wherein said vacuum source provides a pressure between 0.01 torr and 7 tOlT.
v 3. The apparatus of claim 2 wherein the meniscus in the evaporation portion is kept below 1 mm in diame- 4. The apparatus of claim 3 for vaporizing water samples containing deuterium. I
v a a: a: a
that this invention is notto be I

Claims (4)

1. An apparatus for vaporizing liquid samples comprising a tubular member having an inlet portion with a reduced bore, a central evaporation portion having a bore of increasing crosssectional area from the inlet portion to an outlet portion, said outlet portion connected to first and second passage means, said first passage means connected to a sample analyzing device and said second passage means connected to a vacuum source, and valve means releasably blocking said second passage.
2. The apparatus of claim 1 wherein said vacuum source provides a pressure between 0.01 torr and 7 torr.
3. The apparatus of claim 2 wherein the meniscus in the evaporation portion is kept below 1 mm in diameter.
4. The apparatus of claim 3 for vaporizing water samples containing deuterium.
US803635A 1969-03-03 1969-03-03 Sampling device for mass spectrometric analysis Expired - Lifetime US3681598A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US80363569A 1969-03-03 1969-03-03

Publications (1)

Publication Number Publication Date
US3681598A true US3681598A (en) 1972-08-01

Family

ID=25187071

Family Applications (1)

Application Number Title Priority Date Filing Date
US803635A Expired - Lifetime US3681598A (en) 1969-03-03 1969-03-03 Sampling device for mass spectrometric analysis

Country Status (5)

Country Link
US (1) US3681598A (en)
JP (1) JPS4941585B1 (en)
FR (1) FR2037150B1 (en)
GB (1) GB1293472A (en)
NL (1) NL142781B (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5517026A (en) * 1995-01-20 1996-05-14 The United States Of America As Represented By The Secretary Of The Army On-the-move surface sampling head for a mass spectrometer
DE102006030310B3 (en) * 2006-06-30 2008-02-07 Technotrans Ag Method for analyzing a liquid from a liquid stream or supply, and device for carrying out this method
US20160056029A1 (en) * 2014-08-22 2016-02-25 Bayspec, Inc. Apparatus and Methods for an Atmospheric Sampling Inlet for a Portable Mass Spectrometer
CN112595562A (en) * 2020-12-11 2021-04-02 中国科学院工程热物理研究所 Mass spectrum homothermal in-situ sampling interface capable of being flexibly arranged and mass spectrum homothermal in-situ sampling method

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5517026A (en) * 1995-01-20 1996-05-14 The United States Of America As Represented By The Secretary Of The Army On-the-move surface sampling head for a mass spectrometer
DE102006030310B3 (en) * 2006-06-30 2008-02-07 Technotrans Ag Method for analyzing a liquid from a liquid stream or supply, and device for carrying out this method
US20160056029A1 (en) * 2014-08-22 2016-02-25 Bayspec, Inc. Apparatus and Methods for an Atmospheric Sampling Inlet for a Portable Mass Spectrometer
CN112595562A (en) * 2020-12-11 2021-04-02 中国科学院工程热物理研究所 Mass spectrum homothermal in-situ sampling interface capable of being flexibly arranged and mass spectrum homothermal in-situ sampling method
CN112595562B (en) * 2020-12-11 2022-12-06 中国科学院工程热物理研究所 Mass spectrum homothermal in-situ sampling interface capable of being flexibly arranged and mass spectrum homothermal in-situ sampling method

Also Published As

Publication number Publication date
DE2009961A1 (en) 1970-10-15
GB1293472A (en) 1972-10-18
FR2037150B1 (en) 1975-12-26
JPS4941585B1 (en) 1974-11-09
DE2009961B2 (en) 1972-09-07
NL142781B (en) 1974-07-15
NL7002502A (en) 1970-09-07
FR2037150A1 (en) 1970-12-31

Similar Documents

Publication Publication Date Title
Fitzgerald et al. Subnanogram determination of mercury by two-stage gold amalgamation and gas phase detection applied to atmospheric analysis
US5457316A (en) Method and apparatus for the detection and identification of trace gases
US4962042A (en) Method for on-column injection gas chromatography
JP7072134B2 (en) Sample pre-concentration system and method for use in gas chromatography
US9933398B2 (en) Device and method for extracting compounds contained in a liquid sample with a view to analysing them
US5235843A (en) Method and apparatus for analyzing volatile chemical components in a liquid
CN111295585A (en) High performance sub-ambient temperature multi-capillary chromatography column preconcentration system for volatile chemical analysis by gas chromatography
Bauer et al. Recovery of submilligram quantities of carbon dioxide from gas streams by molecular sieve for subsequent determination of isotopic carbon-13 and carbon-14 natural abundances
KR20130143062A (en) Analysis of molecular contamination in vacuum environments
Szpunar et al. Speciation of mercury by ICP-MS after on-line capillary cryofocussing and ambient temperature multicapillary gas chromatography
JPH04274728A (en) Method and apparatus for preliminary enrichment for analyzing minute amount of component in gas
US3681598A (en) Sampling device for mass spectrometric analysis
US3735565A (en) Enrichment of chromatograph output
US5827944A (en) Sample screening and preparation within a collection vessel
Grob et al. Direct coupling of capillary columns to a mass spectrometer. Technique allowing rapid column interchange
CN110873753B (en) Enrichment method for separating gas-phase free propofol in whole blood sample
CN106950303A (en) The assay method of benzene homologues in biological specimen blood
IE44010B1 (en) Method and apparatus for examining the infrared spectrum of small quantities of materials in the vapour phase
CA3107338A1 (en) System for introducing particle-containing samples to an analytical instrument and methods of use
Björklund et al. Large volume injection GC‐MS in electron capture negative ion mode utilizing isotopic dilution for the determination of polybrominated diphenyl ethers in air
US6152989A (en) Method and apparatus for concentrating solution
JPH0247549A (en) Analyzing apparatus of trace gas component
JPH03197834A (en) Method for measuring evaporation of organic solvent and pretreating device for measurement of evaporation
US3731466A (en) Continuous flow multiple trap for low temperature reduced pressure gas chromatography
RU2794235C1 (en) Device for analysis with additional concentration of the composition of the equilibrium vapor phase