CN2630851Y

CN2630851Y - Gas-phase chromatograph and inductance coupled plasma mass spectrograph/spectrograph combined interface

Info

Publication number: CN2630851Y
Application number: CN 03265180
Authority: CN
Inventors: 张晓辉; 胡克
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-06-06
Filing date: 2003-06-06
Publication date: 2004-08-04
Anticipated expiration: 2013-06-06

Abstract

A coupling interface for gas chromatography and inductively coupled plasma mass spectrometer/spectrometer, includes a housing, a heating and temperature control part and a gas path part, the heating temperature control part includes a heat conduction block, an electrothermal element, a temperature sensor and a temperature controller, the electrothermal element and the temperature sensor are arranged in a hole corresponding to the heat conduction block, the outside of the heat conduction block is coated with a heat preservation layer, the heat conduction block and the temperature controller is positioned in the housing, the panel of the temperature controller is embedded in a corresponding panel hole on one side of the housing; the heating and temperature control part of the utility model can provides a constant high temperature condition for the analyses and carrier gas in the pipes between GC and ICP, analysis can be satisfied. The end A of a three-way valve in the gas path part of the utility model can send the terminal of the GC chromatographic column, and supplemental gas is added in branch port C of the three-way valve through an air compensating pipe, the effluence of the terminal of the GC column and the supplemental gas sent in by the branch port C are transported together to the center tube of the ICP torch, work need of ICP is satisfied. Experiment demonstrates the utility model realizes successfully the connection between GC and ICP-MS, and the signal peak profile detected by the combined device has no significantly broadening or tailing comparing with the peak profile detected by the GC, detection sensitivity is improved remarkably.

Description

Gas chromatograph and icp ms/spectrometer connecting interface

Technical field

The utility model relates to measuring equipment, specifically is a kind of chromatography and icp ms/spectrometer connecting interface.Be mainly used in separation and quantitative measurment to the organism composition.

Background technology

Gas chromatography GC is that a kind of molecular state chemical substance that is widely used is separated and detecting instrument.Its separation function is to realize in chromatographic column, and measuring ability then can be realized by multiple detecting device.The sensitivity and the detectability of these detecting devices are had nothing in common with each other, but generally all can not compare with icp ms (or spectrometer) ICP-MS (or AES) far away, and this situation has limited the analytical applications of GC to a certain extent.

For ICP-MS, input mode generally is by pump the sample to be analyzed of liquid form to be introduced instrument, reaches the torch pipe with aerosol shape after atomizing.At torch mouth of pipe place, the gas of certain proportion and flow velocity, and special energy presentation mode has produced inductively coupled plasma.In plasma, high temperature makes the ion of molecule or solvation become atom or ion, is analyzed and is detected by ICP-MS or other parts (AES) again.But ICP-MS (or AES) generally can only be used for the inorganic samples of analytical solution, and detectability and sensitivity are splendid, but does not separate the function of different molecular, so can not analyze the organic sample of different molecular form.If the two is used in combination, just can bring into play both sides' advantage by joining interface.

Summary of the invention

The purpose of this utility model just provides a kind of GC and ICP-MS (or AES) can being used in combination, with the gas chromatograph and the icp ms/spectrometer connecting interface of performance both sides advantage.

The technical solution of the utility model is: comprise shell, heating temperature control unit and gas circuit assembly, described heating temperature control unit comprises heat-conducting block, heating, temperature sensor and temperature controller, heating and temperature sensor place in the hole of heat-conducting block correspondence, be coated with heat-insulation layer at heat-conducting block, heat-conducting block and temperature controller are loaded in the shell, and the panel of temperature controller is embedded in the shell one side corresponding panel hole; Heating and temperature sensor are connected with the corresponding end of temperature controller respectively; Described gas circuit assembly comprises the threeway of T shape, blowdown pipe, transition conduit, heat pipe, transition conduit is passed described heat-conducting block, the one end passes a side of shell, the other end is connected with a straight end entrance A of threeway, threeway is loaded in the shell, it directly brings out the opposite side that mouthful B passes shell, and a port C of threeway connects an end of blowdown pipe, and the other end of blowdown pipe is connected with the tonifying Qi interface that passes shell; Respectively be with a heat pipe at the two ends of described transition conduit, an end of each heat pipe all is connected with heat-conducting block.

The threeway of described T shape comprises T shape housing, cooperates in the inside of its inlet A and inserts described heat pipe; Transition conduit is made of bimetallic tube, and the inner of transition conduit extends across a port C of threeway, connects the bigger diameter end of a reducer union at the outlet B of threeway; Three port A, B, C in threeway have external thread, and are furnished with pipe nut and O-ring seal.

Be tightly connected by connecting leg and two sleeve pipe nuts and O-ring seal between the outlet B of described threeway and the reducer union.

Effect of the present utility model is by analyzing among the requirements importing ICP with the chromatographic column effluent of GC.At first, analyte will reach ICP by chromatographic column, earlier chromatographic column to be passed the GC shell, is connected to the pipe core (being the analyte carrier gas passage) of the torch pipe of ICP.Outside GC and in this section of torch tube hub pipe space, temperature is near room temperature.And the GC chromatographic column is in the high temperature usually, and its effluent also is a high-temperature gas, can cause the cohesion of analyte by above-mentioned room temperature space the time.This interface provides heat for this section space, to keep uniform temperature (this interface is below 290 ℃).Secondly, the flow of ICP pipe core will have hundreds of could satisfy the instrumental analysis requirement to thousands of ml/min usually.And GC column outlet gas flow is generally several ml/min.This interface replenishes the gas gas circuit for the GC effluent provides, the analytical performance that makes two Instrument crosslinkings not the reason analytic system change and be subjected to appreciable impact.

Heating temperature control of the present utility model unit can provide a higher constant temperature for the analyte in the pipeline between the GC to ICP and carrier gas, has satisfied the needs of analyzing.And the end of the threeway A in the gas circuit assembly of the present utility model can be sent into the tail end of GC chromatographic column, and add additional gas to a port C of threeway by blowdown pipe, the additional gas that the effluent of GC post tail end is sent into the C end is transported to ICP torch tube hub pipe, has satisfied the ICP requirements of one's work.Experiment showed, that the utility model successfully realized being connected of GC and ICP-MS, the signal peak shape that the instrument detecting of combination is obtained is compared no obvious broadening or hangover with the detected peak shape of GC, and detection sensitivity greatly improves.

Description of drawings

Fig. 1 is a structure cross-sectional schematic of the present utility model;

Fig. 2 is the A-A cut-open view of Fig. 1;

Fig. 3 is the B-B cut-open view of Fig. 1;

Fig. 4 is the axial cut-open view of the utility model threeway;

Fig. 5 is that the utility model is connected the synoptic diagram of using with GC with ICP-MS;

Fig. 6 is GC and the ICP-MS experiment detection curve that adopts the utility model to connect.

Embodiment

Referring to Fig. 1 one Fig. 3, the utility model comprises shell 1, heating temperature control unit and gas circuit assembly, described heating temperature control unit comprises heat-conducting block 6, heating 8, temperature sensor 5 and temperature controller 10, heating 8 and temperature sensor 5 place in the hole of heat-conducting block 6 correspondences, be coated with heat-insulation layer 3 at heat-conducting block 6, heat-conducting block 6 and temperature controller 10 are loaded in the shell, and the panel of temperature controller 10 is embedded in the shell one side corresponding panel hole; Heating 8 and temperature sensor 5 are connected with the corresponding end of temperature controller 10 respectively; Described gas circuit assembly comprises T shape threeway 4, blowdown pipe 2, transition conduit 13, heat pipe 14, transition conduit 13 is passed described heat-conducting block 6, the one end passes a side of shell 1, the other end is connected with a straight end entrance A of threeway 4, threeway 4 is loaded in the shell 1, it directly brings out the opposite side that mouthful B passes shell 1, and a port C of threeway 4 connects an end of blowdown pipe 2, and the other end of blowdown pipe 2 is connected with the tonifying Qi interface 12 that passes shell 1; Respectively be with a heat pipe 14 at the two ends of described transition conduit 13, an end of each heat pipe 14 all is connected with heat-conducting block 6.

Referring to Fig. 4, described T shape threeway 4 comprises T shape housing 43, and its inlet A internal diameter matches with the external diameter of described heat pipe 14, inserts heat pipe 14 within it; Described transition conduit 13 is made of bimetallic tube 131, the inner of transition conduit 13 extends across a port C of threeway 4, when using, the other end of transition conduit 13 is connected in the GC post case, penetrates GC chromatographic column 132 and make this end concordant substantially with the inner of transition conduit 13 in the axle center hole of transition conduit 13.Transition conduit 13 is as the heat-conducting layer and the protective seam of GC post 132.Be tightly connected by connecting leg 47 and two sleeve pipe nuts 41 and O-ring seal 42 at the outlet B of threeway 4.The bigger diameter end that connects a reducer union 49; Three port A, B, C in threeway have external thread, and are furnished with pipe nut 41 and O-ring seal 42.

The inner termination of transition conduit 13 of the present utility model strides across the port C in the threeway, and the normal temperature tonifying Qi of propping up port C from threeway can make it to be easy to transmit around the effluent of living chromatographic column like this, and this is the basis that this interface function realizes.

The reducer union 49 of threeway 4 attenuates follow-up caliber, thereby has strengthened the flow velocity of gas, makes the chromatographic column effluent arrive the torch pipe D of ICP rapidly.The result replenishes the band of gas the chromatogram effluent just arrived the torch pipe about 0.1 second, and can not condense on tube wall or keep, and avoids the signal peak shape that significant broadening or conditions of streaking are arranged.

The tubule of being drawn by reducer union 49 50 is made for resilient inert material, as teflon etc., can prevent the possible chromatographic column effluent and the absorption or the chemical reaction of tube wall.

Referring to Fig. 5, this is the syndeton synoptic diagram of the utility model and GC and ICP-MS.As can be seen from Figure, the utility model inserts the endpiece sealing of the chromatographic column E of GC in the transition conduit 13 of gas circuit assembly when using, and makes the inner concordant of its inner and transition conduit 13.The endpiece B of threeway 4 of the present utility model is tightly connected by the pipe core of described tubule 50 with ICP torch pipe D.The interface 12 of a port C of threeway 4 is connected with the additional source of the gas F of ICP-MS.

Fig. 6 shows and adopts the described system of Fig. 5 to three kinds of organometallicss (triethyl butyl tin, diethyl dibutyl tin and tetrabutyltin, or be called MBT, DBT and TBT) empirical curve that detects, transverse axis is the time among the figure, the longitudinal axis is a signal intensity, and the signal peak of Pai Lieing is represented sample introduction peak G, MBT, DBT and TBT respectively in chronological order.The result shows, compare with detecting with the GC-hydrogen flame detector, use GC/ICP-MS system to detect based on this interface, the relative retention time of three kinds of compounds does not all have obvious change, half-peak breadth (peak width at half place of peak height) value is at 1.6-2.0 between second (with hydrogen flame detector time be 1.5-1.8 second), also do not have significantly to change.Under the condition of hand sampling, carry out when quantitative with the area of signal peak, standard deviation is in 4%, and repeatability is good, can be used for quantitative test fully.General better with the meeting of auto injection effect.

Claims

1, a kind of gas chromatograph and icp ms/spectrometer connecting interface, it is characterized in that: comprise shell (1), heating temperature control unit and gas circuit assembly, described heating temperature control unit comprises heat-conducting block (6), heating (8), temperature sensor (5) and temperature controller (10), heating (8) and temperature sensor (5) place in the corresponding hole of heat-conducting block (6), be coated with heat-insulation layer (3) at heat-conducting block (6), heat-conducting block (6) and temperature controller (10) are loaded in the shell, and the panel of temperature controller (10) is embedded in the shell one side corresponding panel hole; Heating (8) and temperature sensor (5) are connected with the corresponding end of temperature controller (10) respectively; Described gas circuit assembly comprises T shape threeway (4), blowdown pipe (2), transition conduit (13), heat pipe (14), transition conduit (13) is passed described heat-conducting block (6), the one end passes a side of shell (1), the other end is connected with a straight end entrance A of threeway (4), threeway (4) is loaded in the shell (1), it directly brings out the opposite side that mouthful B passes shell (1), a port C of threeway (4) connects an end of blowdown pipe (2), and the other end of blowdown pipe (2) is connected with the tonifying Qi interface (12) that passes shell (1); Respectively be with a heat pipe (14) at the two ends of described transition conduit (13), an end of each heat pipe (14) all is connected with heat-conducting block (6).

2, gas chromatograph according to claim 1 and icp ms/spectrometer connecting interface, it is characterized in that: described T shape threeway (4) comprises T shape housing (43), cooperates in the inside of its inlet A and inserts described heat pipe (14); Transition conduit (13) is made of bimetallic tube (131), and the inner of transition conduit (13) extends across a port C of threeway (4), connects the bigger diameter end of a reducer union (49) at the outlet B of threeway (4); Three port A, B, C in threeway have external thread, and are furnished with pipe nut (41) and O-ring seal (42).

3, gas chromatograph according to claim 1 and icp ms/spectrometer connecting interface is characterized in that: be tightly connected by connecting leg (47) and two sleeve pipe nuts and O-ring seal between the outlet B of described threeway (4) and the reducer union (49).