US3798973A - Sample method and arrangement for gas chromatograph - Google Patents

Sample method and arrangement for gas chromatograph Download PDF

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Publication number
US3798973A
US3798973A US00271901A US27190172A US3798973A US 3798973 A US3798973 A US 3798973A US 00271901 A US00271901 A US 00271901A US 27190172 A US27190172 A US 27190172A US 3798973 A US3798973 A US 3798973A
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Prior art keywords
plug
flow
stream splitting
stream
volume
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US00271901A
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English (en)
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W Estey
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Applied Biosystems Inc
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Perkin Elmer Corp
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Priority to US00271901A priority Critical patent/US3798973A/en
Priority to DE19732334624 priority patent/DE2334624A1/de
Priority to CA176,152A priority patent/CA1004999A/en
Priority to CH1014273A priority patent/CH588073A5/xx
Priority to AU58012/73A priority patent/AU481254B2/en
Priority to JP48079208A priority patent/JPS4954095A/ja
Priority to GB3354073A priority patent/GB1434987A/en
Priority to IT51455/73A priority patent/IT1011010B/it
Priority to FR7326630A priority patent/FR2192853B3/fr
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Anticipated expiration legal-status Critical
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
    • G01N30/02—Column chromatography
    • G01N30/04—Preparation or injection of sample to be analysed
    • G01N30/06—Preparation
    • G01N30/10—Preparation using a splitter
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
    • G01N30/02—Column chromatography
    • G01N30/26—Conditioning of the fluid carrier; Flow patterns
    • G01N30/28—Control of physical parameters of the fluid carrier
    • G01N30/34—Control of physical parameters of the fluid carrier of fluid composition, e.g. gradient
    • G01N2030/347—Control of physical parameters of the fluid carrier of fluid composition, e.g. gradient mixers

Definitions

  • ABSTRACT A method for providing enhanced stream splitting is provided by conveying a plug comprising a mixture of a sample material and carrier gas to a stream splitting means and initially dividing a leading portion of the plug during a relatively short interval of time into a measurement component and into a discharge compo- Man-26, 1974 graphic column. The second split ratio is thereby maintained substantially constant for the passage of the remaining and principal portion of the plug past a split station of the stream splitting means.
  • a chromatographic apparatus in accordance with features of the invention comprises a stream splitting means, means providing a flow channel communicating between a first outlet of the stream splitting means and a separating column, and means providing a second flow channel communicating between a second outlet of the stream splitting means and a flow restrictor 'means which is vented to atmosphere.
  • the second flow channel has a relatively small volume for providing that a discharge component of the plug which flows therein after splitting is rapidly vented to atmosphere.
  • the discharge volume is substantially less in magnitude than the volume of the plug.
  • a gas chromatograph as is known, is an analytical instrument which separates a sample material into constituents by conveying a plug comprising a mixture of sample material in a vaporized state and a substantially larger volume of carrier gas through a separating column.
  • the constituents which experience different transit times through the column elute successively in time from the column to provide a quantitative indication of the constituents of the sample.
  • An effluent of the column is coupled to a detection and indicating means which senses the occurrence of generally bell shaped peaks associated with each of the constituents and which provides an indication of their height, area and shape. 7
  • chromatographic column comprises an elongated capillary or open tubular column which is coated on an inner surface thereof with a separating medium.
  • a support material is formed as an open tubular liner within the capillary column, and the separating medium is deposited on the support material.
  • a second type of chromatographic column comprises an elongated tube which is packed with a support material and upon which the separating medium is deposited.
  • the capillary or open tubular column has an operating characteristic which necessitates the introduction ofa relatively smaller plug quantity than can be accommodated by a packed column.
  • the plug volume which can be handled by a capillary column is generally on the order of 1/10 to l/10,000 of the quantity which is applied to a packed column.
  • the corresponding small sample quantity renders the sample impractical to handle.
  • sample volumes within the range of about 0.5 to l microliters are introduced to the instrument at an injection station and form substantially larger plug mixtures with the carrier gas.
  • the plug quantity is then automatically reduced by a stream splitting means prior to entry onto a capillary column.
  • the stream splitting means divides the plug in accordance with a predetermined split ratio into a relatively small quantity measurement component which flows to the column'and into a relatively large quantity discharge component which is conveyed through a discharge volume and flow restriction to atmosphere.
  • the plug of sample material and carrier gas be substantially fully homogenized before stream splitting occurs.
  • non-linearities which can be introduced by the stream splitting means interefere with the separation and reduce its accuracy.
  • full homogenization is not always achieved and attempts have been made to reduce stream splitting non-linearities.
  • linearity occurs when the flow rate of the plug sample mixture remains relatively constant during the passage of the plug past the stream splitting point or junction.
  • the carrier gas exhibits relatively constant velocity or flow rate as it goes through the various flow paths and channels of the inlet system of the chromatograph.
  • One stream splitting arrangement which overcomes this undesirable non-linear affect includes a discharge channel having a volume which is greater than thevolume of the largest plug expected to be handled by the instrument.
  • the use of this relatively large discharge volume assures that the entire plug will have passed the split station before a leading front of the discharge component of the plug reaches the flow restriction and is vented to atmosphere.
  • the flow viscosity of the discharge component of the plug and the downstream pressure is then maintained relatively constant throughout the occurrence of the split. While this arrangement has provided highly useful and advantageous results, it necessitates the use of a relatively large discharge volume thereby undesirably increasing the size of the injection and stream splitting means.
  • the plug mixture for these quantities can have a typical volume of 5 cc.
  • the instrument operator is required to limit the quantity of the plug to a volume which is less than the volume of the discharge channel. This can then limit the sample quantity and carrier flow rates which can be employed. At times this requirement is not fulfilled and the stream splitting ratio is disadvantageously affected.
  • Another object of the invention is to provide an improved injection arrangement for a gas chromatograph.
  • Another object of the invention is to provide an improved stream-splitting means for use with a gas chromatograph which provides a substantially uniform splitting ratio during transit of a plug past a stream splitting station.
  • Another object of the invention is to provide an improved injection and stream-splitting arrangement for an open tubular column having a size adapted which is readily interchangeable with packed column injection and stream splitting means of present day chromatographs.
  • Another object of the invention is to provide an improved open tubular column injection and stream splitting arrangement having a relatively small size, yet which provides substantial linearity in stream splitting.
  • Another object of the invention is to provide a sample injection and stream splitting arrangement for open tubular columns which can be fabricated at substantially less cost than present day arrangements.
  • a further object of the invention is to provide an improved injection arrangement which provides enhanced sample-carrier gas mixing and homogenization.
  • a plug comprising a mixture of a sample material and carrier gas is conveyed to a stream splitting means and a leading portion thereof is initially divided during a relatively short interval of time into a measurement component and into a discharge component.
  • the division is automatically altered to a second value according to which the remaining and principal portion of the plug is divided by conveying the discharge component through a relatively small discharge volume and flow restriction to atmosphere.
  • the measurement component of the plug is simultaneously conveyed toward a chromatographic column.
  • the second split ratio is thereby maintained substantially constant for the transit of the remaining and principal portion of the plug past a split station of the stream splitting means.
  • the discharge component of the plug is preferably vented to atmosphere simultaneously with the initial splitting of the plug into measurement and discharge quantities.
  • a practical discharge volume must exhibit finite dimensions, and a relatively short transit time is required for conveying the dishcarge component from the split station to atmosphere.
  • a chromatographic apparatus in accordance with features of the invention comprises a stream splitting means,'means providing a flow channel communicating between a first outlet of the stream splitting means and a separating column, and means providing a second flow channel communicating between a second outlet of the stream splitting means and a' flow restrictor means which-is vented to atmosphere.
  • the second flow channel has a relatively small volume for providing that a discharge component of the plug which flows therein after splitting is rapidly vented to atmosphere.
  • the discharge volume is substantially less in magnitude than the volume of the plug thereby providing a substantially constant flow rate of the plug past the splitting station.
  • mixing of the sample and carrier gas to provide a sample plug of enhanced homogenity is provided by a sample injector having a flow channel formed by a cylindrically shaped body and a plurality of segments of disc shaped stream diverting members supported within the cylinder and extending into the cylindrical flow passage alternatively from different circumferential locations on the inner surface of the cylinder.
  • the carrier stream flowing through the cylinder thereby repeatedly alters its direction of passage and the resulting turbulence enhances mixing of the sample material and flowing carrier stream to provide a plug of enhanced homogenization.
  • FIG. 1 is a schematic diagram in block form illustrating a chromatographic apparatus incorporating features of the present invention
  • FIG. 2 is a more detailed schematic view of a sample injection and stream splitting arrangement of FIG. 1;
  • FIGS. 3a,'3b and 3c are diagrammatic representations illustrating the transit of a plug mixture past a stream splitting station of a prior art arrangement
  • FIGS. 4a, 4b and 4c are diagrammatic representations illustrating the transit of a plug mixture past a stream splitting station and which is useful in describing the operation of the present invention
  • FIG. 5 is a side elevation view, partly in section, illustrating an injector and stream splitting arrangement constructed in accordance with features of the present invention
  • FIG. 6 is a sectional view taken along lines 6-6 of FIG. 5;
  • FIG. 7 is a sectional view taken along lines 7-7 of FIG. 5;
  • FIG. 8 is a sectional view taken-along lines 88 of I FIG. 5;
  • FIG. 9 is an enlarged view of a portion of FIG. 5.
  • the chromatographic instrument illustrated therein includes a source of carrier gas 10.
  • Carrier gas is conveyed by a suitable tubulation 11 from the source 10 to an injector and stream splitting means 12.
  • the injector and stream splitting means 12 is demountably supported by a heated injector block 14 which maintains the injector andstream splitter at a desired temperature.
  • the injector is adapted for receiving, vaporizing, and mixing a sample with the stream of the carrier gas.
  • the sample which typically has a volume on the order of 0.5 to 10 microliters is introduced into the injector means 12 from a syringe 16.
  • the sample thus inserted forms a mixture or plug of vaporized sample material and carrier gas, a measurement portion or component of which is conveyed to an open tubular chromatographic column 18 and a discharge portion or component of which is conveyed to atmosphere through a vent 20.
  • the sample measurement component is transported through the column 18 and is separated into constituents which experience different tranof the injector sit times in the column.
  • An effluent of the column is coupled to a detector 22.
  • the detector 22 which comprises, for example, an ionization detector, senses the occurrence of constituent peaks and provides an electrical indication thereof. This electrical indication is applied to an indicator, as for example, a strip chart recorder, which forms a chromatogram having a series of bell shaped peaks, the areas of which are indicative of the concentration of the associated constituents of the sample.
  • the injector and stream splitting means 12 is schematically illustrated in greater detail in FIG. 2.
  • the syringe 16 includes a probe 24 which extends through a septum 26 into a relatively narrow bore tube 28.
  • Carrier gas from the source 10 flows through a channel formed between the bore 28 and a concentrically located tube 29.
  • the carrier gas flows into the bore 28 where it picks up the sample which is ejected by the probe 24.
  • the sample thus deposited in the flowing carrier stream is transported to a mixing chamber where the sample is mixed with the carrier gas to provide a homogenized plug 31.
  • the plug 31 will have a volume which is principally determined by the duration of injection and the carrier gas flow rate.
  • the plug will have a volume of about 5cc.
  • the plug flowing from the mixing chamber 30 flows toward a stream splitting station referenced by the dotted line 32.
  • the plug is divided at the station 32 into a measurement component 33 which flows along a portion of a first channel 34 to the chromatographic column and into a discharge component 35 which flows through a discharge volume 36 to a flow restricting means 38.
  • the effluent of this flow restricting means is vented to atmosphere.
  • Atmospheric conditions for the purposes of this application represents the external environmental conditions under which an analytical instrument operates.
  • the plug 31 is divided at the split station 32 in accordance with a predetermined ratio R.
  • the ratio R will have a value within the range of about 1/10 to about l/I0,000.
  • the ratio R is determined principally by the flow restriction of the column connected to the channel 34, and the flow restriction provided by the flow restricting means 38 connected to channel 36.
  • the split ratio R is disadvantageously subject to variation when the discharge component of a plug is vented to atmosphere before substantially the entire volume of the plug has completed its transit past the splitting station 32. Stated alternatively, the plug is undesirably subjected to a variation in flow rate during its transit at the splitting station.
  • a prior arrangement for avoiding this variation in R is illustrated and described with respect to FIGS. 3a, 3b and 3c.
  • the plug of sample material 31 is represented by the cross-hatched section.
  • FIG. 3a illustrates the location of the plug as it reaches the stream splitting station 32.
  • FIG. 3b illustrates the division of'the plug shortly after a leading from 42 of the plug has passed the station 32.
  • a discharge component 35 of the plug is very rapidly conveyed to atmosphere upon passing the split station 32.
  • the flow rate of the discharge component 35 is immediately altered from an initial value to a second substantially constant value corresponding to the downstream venting of the discharge component.
  • the split ratio R will remain substantially constant throughout the interval while the remainder and principal portion of the plug is in transit past the split station 32. This advantageously provides for an enhanced split operation in that the split ratio R changes immediately from an initial value R to a second vaue R which value remains substantially constant throughout the transit of the remainder and principal portion of the plug past the split station 32.
  • This rapid initial variation in split ratio is accomplished by providing a relatively small discharge volume 36.
  • the discharge volume 36 is substantially less than the volume of the plug. Its small size is limited by the practical requirements for providing a ventingmeans of finite dimensions which is adapted for supporting the flow restriction 38 and does not create greater flow impedance in'conjunction with the restriction 38 than can be tolerated for the desired split ratio.
  • the relatively small discharge volume further contributes significantly to an overall reduction, in size of the injector and stream splitting means thereby rendering it interchangeably mountable withinjector means for packed column and substantially reducing its cost of fabrication.
  • the chromatographic injector station includes the heater block 14 having an integral injector heater and support segment 50.
  • the segment includes a bore extending longitudinally therethrough for receiving an injector assembly.
  • a radially extending bore is formed in the heater block segment 50 for receiving a carrier gas inlet tubulation 52.
  • the injector assembly which is demountably positioned in the segment 50 includes an elongated generally tubular shaped housing 54 having an integrally formed generally rectangular shaped segment 56 positioned at one end of this housing.
  • the rectangular shaped segment 56 supports a flow restricting means and shut-off valve for conveying a discharge portion of a plug to atmosphere.
  • a liner assembly Concentrically positioned in the injector housing 54 is a liner assembly which includes an elongated tubular shaped body 58 extending from an inlet or right hand end of the injector as viewed in FIG. 5 toward a central location within the injector housing 54.
  • the liner assembly further comprises an elongated concentrically'located liner body 60 which-is formed of glass and which includes a generally conically shaped outlet end surface 62- which is seated against a conforming surface of an insert body 64 near one end of the cylindrical body 58.
  • the liner body 60 includes a longitudinally extending bore 65 which extends between an injection station and the insert 64.
  • carrier gas flows through a channel which includes the bore 65 and a bore 66 which is formed in the insert body 64.
  • the conically shaped surface 62 is secured against a conforming surface of the insert 64 by a helical spring 68 which is positioned about the body and contacts a shoulder segment 70 thereof and by an elongated tubular sleeve 72 which is positioned about theliner 60.
  • This assembly inhibits carrier gas from leaking from the tube 52 directly to the bore 66 without sweeping'past the sample injection station.
  • the assembly of the liner body 60, the sleeve 72, and the cylindrical body 58 extend through a tubular shaped member 74 to a probe entry or injection station.
  • the member 74 is fitted and brazed into a bore formed in the ring 56.
  • An enlarged threaded outer surface 78 is formed near one end of the member 74 and a septum cap 79 engages this threaded surface.
  • a probe penetrable cylindrically shaped septum 80 formed of rubber, for example, and an optionally used disc shaped septum shield 81 formed, for example, of Teflon are positioned within the cap 79.
  • the Teflon disc bears against one end of the sleeve 72 thereby exerting a force on the spring which seats the liner 60 against the insert 64.
  • the septum 80 provides a probe penetrable seal through which the syringe needle or probe 24 (H6. 2) is introduced.
  • the probe which is initially introduced through a bore 84 in the cap 79, through the septum 80, through the shield 81 and through a bore 86 in the sleeve 72, extends into the bore 65 of the liner 60.
  • Carrier gas flows to this injector assembly through the tubulation 52 and a bore 88 formed in the injector housing 54.
  • the gas flows from the bore 88 to a concentrically located ring shaped channel formed between an inner surface of the housing 54 and an outer surface of the body 58.
  • Carrier gas then flows through and from this ring shaped channel via a plurality of apertures 90 formed in the body 58 to a ring shaped channel extending between the inner surface of the body 58 and an outer surface of the sleeve 72 toward the spring 68.
  • a ring shaped flow channel extends between an outer surface of the liner 60 and an inner surface of the sleeve 72.
  • the mixing chamber 100 is formed with a relatively wide cross-sectional area and a relatively short length in comparison with present day arrangements employed with open tubular columns.
  • baffle members 102 which are positioned within the housing 54.
  • These baffle members 102 comprise segments of discs which are secured to a rod 103 and extend from opposite sides of the inner surface of the injector housing 54. They have a segmented disc shape which conforms to a portion of the inner circumference of the housing 54 and a flat 105.
  • a flow passage 106 is provided between the flat of each member 102 and the inner surface of the housing 54.
  • the flats 105 of adjacent members are alternately oppositely positioned. The direction of travel of the plug and carrier stream is thereby repeatedly altered by this baffle assembly and the transit time of the plug is thereby increased. An enhanced mixing and homogenization of the plug is thus provided.
  • the flowing carrier gas stream and plug which exit from the mixing chamber pass through a ring shaped spacer body 107, similar to 100, into a stream splitting member 108 having an outer diameter thereof which extends within the bore of the injector housing 54 and which is secured thereto by brazing, for example.
  • the splitting member 108 has integrally formed therein a conically shaped bore 110 and a cylindrically shaped bore.
  • a thin walled injector tube assembly 112 extends through the cylindrical bore toward the conical bore 110.
  • the tube 112 includes a conically shaped tip 116 having an inlet orifice 118.
  • the tube 112 further in-.
  • a conventional swage lock means 119 secures the tube 112 within the split body 108.
  • Carrier gas and the measurement component which flow in the tube 112 enter this tube through the origice 118 of the conical segment 116.
  • a transverse plane, provided by the section lines 66 at the orifice, represents a stream split station equivalent to the split station 32 of FIGS. 2-4.
  • the measuring plug component and carrier gas which flow through the orifice 1 18 is conveyed through the tube 112 and through a tubulation 120 and a column coupling means 122 to an open tubular separating column.
  • the discharge component of the plug is conveyed about the outer surface of the cone shaped member 116 and through a thin-walled tubulation 132 which is fitted into a radially extending bore 133 in the member 108.
  • a recess 134 (P16. 7) is formed in and extends longitudinally through the wall of the housing 54. This recess is adapted for receiving and positioning the tubulation 132.
  • the tubulation 132 extends along the length of the housing 54 within the recess 134 and extends into a bore 135 which communicates with an open space 136 formed in the rectangular shaped segment 56 of the injector housing 54.
  • a cylindrically shaped flow restrictor support block 140 is positioned in the space 136 which is formed at an angle with respect to the axis of the injector and the rectangular shaped segment 56.
  • This block which is brazed to the segment 56 includes an internal bore 142 threaded along a portion of its'length for receiving and engaging a flow restrictor 144.
  • the flow restrictor is generally cylindrically shaped and includes a longitudinal bore extending therethrough of predetermined dimensions for establishing a desired flow impedance to the discharge component of the carrier gas and plug.
  • the flow restrictor is threaded about an outside surface thereof and engages the internally threaded segment of the bore 142.
  • the discharge component of the plug flows successively through the tubulation 132, and the bore 135, space 136, bore 142 and the bore of flow restrictor 144.
  • a vent control is provided for alternatively providing a substantially unobstructed flow passage between the outlet of the restrictor 144 and atmosphere or for establishing a bleed vent for conserving carrier gas when a sample analysis is not in progress.
  • the ventcontrol includes a tubular shaped vent port body 150 having internal threads which engage external threads formed on an outer surface of the block 140.
  • An ring 152 provides a gas-tight seal at this union.
  • a valve block 154 is fitted about the port body 150 at one end thereof and a gas-tight seal is provided therebetween by an 0 ring 156.
  • the port body 150 includes an internal conically shaped end segment which converges to a bore 158 communicating with a bore 160 in the valve block 154.
  • the valve block which is annular shaped, includes a sliding valve member 162.
  • This valve member is adapted to be positioned in a valve bleed position, as illustrated in FIG. 5, or in a vent position.
  • the bore 160 communicates with a bore 164 l in the slide body.
  • a cylindrical bore 166 of enlarged cross-section is .formed in the slide body 162 and a body of sintered material 168 is positioned therein.
  • the carrier gas and discharge plug component flow from the restrictor 144, through the bores 158, 160 and 164 and through the sintered material 168 to atmosphere.
  • the sintered material establishes a flow impedance creating a back pressure which reduces the carrier flow and conserves the carrier gas when a sample analysis is not in progress.
  • the instrument operator actuates the slide 162 by pressing it in a generally upward direction thereby longitudinally translating the slide member and transferring a bore 170 and an outlet venting tube 172 into communication with the bore 160 and the valve body 154.
  • the discharge component of carrier gas and the plug which flow from the restrictor 144 thereby flow through a relatively unobstructed flow passage to atmosphere.
  • the injector and'stream splitting assembly are secured in the heater block 14 by a clamp 145 which engages the rectangular segment 56 of the housing 54 and which is screw mounted to the heater block segment 50.
  • the assembly is thereby readily demountable by decoupling the column flow cover 122 and by removing the clamp 145.
  • the discharge component of the plug is conveyed to atmosphere almost immediately after passing the splitting station 32 by providing a relatively small discharge volume.
  • the discharge volume comprises the volume between the outlet port 133 and the split station, the volume of the port 133, the volume of the tubulation 132, the volume of 'the port 135 and the space 136 leading to the flow restrictor 144.
  • an injection and stream splitting means for an open tubular chromatographic column which is relatively smaller than present day arrangements.
  • an interval of time, T during which the carrier gas and the sample which is injected into the carrier gas stream are mixed is significant because of the necessity of obtaining a homogeneous mixture prior to splitting.
  • the mixing chamber of FIG. 5 provides a mixing time interval comparable with present day mixing chambers while still providing a relatively compact structural arrangement. This is accomplished by providing a relatively short mixing chamber length of relatively wide cross-section and by providing the flow diverting and turbulence disc members 102.
  • the discharge volume has a magnitude which at a predetermined carrier flow rate and within a range of split ratios, provides for the transit of a leading front 43 of the plug discharge component through the discharge volume in an interval of time equal to about 1 percent of the time required for the plug to traverse the split station and generally not exceeding about 2 h percent of this interval of time.
  • a particular injector and stream splitting arrangement not deemed limiting inany respect includes a mixing chamber having a length of about 5.49 centimeters, a diameter of about 0.952 centimeters and a discharge volume principally composed of the elongated tube 132 having a length of about 10.8 centimeters and a diameter of about 0.0635 centimeters.
  • a mixing chamber having a mixing chamber and discharge volume of these approximate dimensions, two samples were injected into the system.
  • a first sample comprises a standard test mixture of C., to C straight chain hydrocarbons with -a boiling point range of from about' 93.5 to about 159C.
  • Sample sizes ranging in size from 0.5 to 10.0 microliters and a range of split ratios from 1:16 to 1:418 were employed and were separated on a 300 foot by 0.01 inch inside diameter wall coated column AP-L at split ratios of 1:74 to 1:418 as well as a 50 foot long 0.02 inch inside diameter support coated column AP-L with a split ratio of 1:16. Relatively good reproducible quantitative results were obtained.
  • a second sample comprises a mixture of C to C straight chain hydrocarbons having a boiling point range of about 144C. to a vapor pressure of 40 MM at 282C. A gas chromatographic column oven was programmed during the, examination of this sample.
  • a sample injection arrangement for a gas chromato-graph having an open tubular separating. column comprising:
  • a stream splitting body positioned atone end of said housing member and having an inlet aperture extending into a frustro-conically shaped bore;
  • said stream splitting body including a thin-walled conically shaped body positioned near a narrow portion of said frustro-conically shaped bore and forming with said frustro-conically shaped bore a stream splitting station;
  • said flow impedance means having an outlet aperture exposed to atmospheric conditions.
  • tubular housing has a longitudinal axis, a recess formed in said body and extending in a direction substantially parallel to saidaxis, and said elongated body is positioned in said recess.
  • the apparatus of claim 1 including means positioned within said tubular housing for mixing the sample and carrier gas, said means comprising a plurality of disc segments extending in a generally radial direction within said housing from different circumferential locations within said housing and positioned at different longitudinal sections in said housing.
  • a flow-channel is provided for conveying a sample quantity and carrier gas to said mixing chamber and said disc segments are positioned circumferentially within said housing for causing a carrier gas stream flowing therethrough to repeatedly alter the direction of flow.

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US00271901A 1972-07-14 1972-07-14 Sample method and arrangement for gas chromatograph Expired - Lifetime US3798973A (en)

Priority Applications (9)

Application Number Priority Date Filing Date Title
US00271901A US3798973A (en) 1972-07-14 1972-07-14 Sample method and arrangement for gas chromatograph
DE19732334624 DE2334624A1 (de) 1972-07-14 1973-07-07 Verfahren und vorrichtung zur probenaufgabe bei gaschromatographen
CH1014273A CH588073A5 (US07321065-20080122-C00160.png) 1972-07-14 1973-07-11
CA176,152A CA1004999A (en) 1972-07-14 1973-07-11 Sample method and arrangement for gas chromatograph
AU58012/73A AU481254B2 (en) 1973-07-12 Imrpoved sample injection method and arragement for gas chromatography
JP48079208A JPS4954095A (US07321065-20080122-C00160.png) 1972-07-14 1973-07-13
GB3354073A GB1434987A (en) 1972-07-14 1973-07-13 Sample method and arrangement for gas chromatograph
IT51455/73A IT1011010B (it) 1972-07-14 1973-07-13 Metodo e sistema di apparecchiature per l iniezione di campioni da ana lizzare in colonne gascromatogra fiche
FR7326630A FR2192853B3 (US07321065-20080122-C00160.png) 1972-07-14 1973-07-13

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JP (1) JPS4954095A (US07321065-20080122-C00160.png)
CA (1) CA1004999A (US07321065-20080122-C00160.png)
CH (1) CH588073A5 (US07321065-20080122-C00160.png)
DE (1) DE2334624A1 (US07321065-20080122-C00160.png)
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GB (1) GB1434987A (US07321065-20080122-C00160.png)
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Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4367645A (en) * 1980-12-03 1983-01-11 Kinetics Technology International Corporation Hot gas sampling
US4766760A (en) * 1987-11-03 1988-08-30 Vsesojuzny Nauchno-Issledovatelsky I Konstruktorsky Istitute Khromatografii Method of chromatographic analysis of a mixture of liquid substances and a gas chromatograph for carrying out the method
US4842825A (en) * 1986-06-19 1989-06-27 Ruska Laboratories, Inc. Apparatus for determining chemical structure
US4895032A (en) * 1984-09-26 1990-01-23 Studiengesellschaft Kohle Mbh Process and device for split and splitless sampling onto capillary columns using the syringe
US5119669A (en) * 1990-07-31 1992-06-09 Restek Corporation Sleeve units for inlet splitters of capillary gas chromatographs
US5205845A (en) * 1990-09-28 1993-04-27 The Regents Of The University Of Michigan Mechanical gas chromatography injection valves and column multiplexing techniques
US5281256A (en) * 1990-09-28 1994-01-25 Regents Of The University Of Michigan Gas chromatography system with column bifurcation and tunable selectivity
US5288310A (en) * 1992-09-30 1994-02-22 The Regents Of The University Of Michigan Adsorbent trap for gas chromatography
US5467635A (en) * 1994-12-12 1995-11-21 Shimadzu Corporation Gas chromatograph
ES2103224A1 (es) * 1994-05-18 1997-09-01 Univ Cordoba Analizador automatico para el tratamiento previo de muestras liquidas.
US5741960A (en) * 1994-05-27 1998-04-21 Daniel Industries, Inc. Probe chromatograph apparatus and method
US6301952B1 (en) * 1998-12-30 2001-10-16 Varian, Inc. Gas chromatographic device
US20100122564A1 (en) * 2008-11-18 2010-05-20 Eric Crosson Liquid sample evaporator for vapor analysis

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3708504A1 (de) * 1987-03-16 1988-09-29 Siemens Ag Einrichtung zur stroemungsteilung bei der gaschromatographischen analyse
DE19703452A1 (de) * 1996-02-29 1997-09-04 Hewlett Packard Co System zum schnittstellenmäßigen Verbinden von Probenvorbereitungsgeräten mit einem Chromatograph
EP2626697B1 (en) * 2012-02-07 2018-10-31 King Saud University Liquid chromatography device

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB971678A (en) * 1962-03-05 1964-09-30 Perkin Elmer Corp Gas chromatography injector

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB971678A (en) * 1962-03-05 1964-09-30 Perkin Elmer Corp Gas chromatography injector

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4367645A (en) * 1980-12-03 1983-01-11 Kinetics Technology International Corporation Hot gas sampling
US4895032A (en) * 1984-09-26 1990-01-23 Studiengesellschaft Kohle Mbh Process and device for split and splitless sampling onto capillary columns using the syringe
US4972729A (en) * 1984-09-26 1990-11-27 Studiengesellschaft Kohle Mbh Device for split and splitless sampling onto capillary columns using a syringe
US4842825A (en) * 1986-06-19 1989-06-27 Ruska Laboratories, Inc. Apparatus for determining chemical structure
US4766760A (en) * 1987-11-03 1988-08-30 Vsesojuzny Nauchno-Issledovatelsky I Konstruktorsky Istitute Khromatografii Method of chromatographic analysis of a mixture of liquid substances and a gas chromatograph for carrying out the method
US5119669A (en) * 1990-07-31 1992-06-09 Restek Corporation Sleeve units for inlet splitters of capillary gas chromatographs
US5205845A (en) * 1990-09-28 1993-04-27 The Regents Of The University Of Michigan Mechanical gas chromatography injection valves and column multiplexing techniques
US5281256A (en) * 1990-09-28 1994-01-25 Regents Of The University Of Michigan Gas chromatography system with column bifurcation and tunable selectivity
US5288310A (en) * 1992-09-30 1994-02-22 The Regents Of The University Of Michigan Adsorbent trap for gas chromatography
ES2103224A1 (es) * 1994-05-18 1997-09-01 Univ Cordoba Analizador automatico para el tratamiento previo de muestras liquidas.
US5741960A (en) * 1994-05-27 1998-04-21 Daniel Industries, Inc. Probe chromatograph apparatus and method
US5467635A (en) * 1994-12-12 1995-11-21 Shimadzu Corporation Gas chromatograph
US6301952B1 (en) * 1998-12-30 2001-10-16 Varian, Inc. Gas chromatographic device
US20100122564A1 (en) * 2008-11-18 2010-05-20 Eric Crosson Liquid sample evaporator for vapor analysis
US8181544B2 (en) * 2008-11-18 2012-05-22 Picarro, Inc. Liquid sample evaporator for vapor analysis

Also Published As

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FR2192853B3 (US07321065-20080122-C00160.png) 1976-07-02
CH588073A5 (US07321065-20080122-C00160.png) 1977-05-31
IT1011010B (it) 1977-01-20
JPS4954095A (US07321065-20080122-C00160.png) 1974-05-25
AU5801273A (en) 1975-01-16
CA1004999A (en) 1977-02-08
GB1434987A (en) 1976-05-12
FR2192853A1 (US07321065-20080122-C00160.png) 1974-02-15
DE2334624A1 (de) 1974-01-24

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