JP5050592B2 - Pyrolysis gas chromatograph - Google Patents

Description

  The present invention relates to a gas chromatograph for measuring component concentrations in various samples, and more particularly to a pyrolysis gas chromatograph apparatus including a pyrolysis section, a column, and a detection section.

FIG. 6 shows a schematic configuration diagram of a conventional gas chromatograph apparatus. This apparatus detects a carrier gas cylinder 91 for transporting a sample to a detector, a flow rate adjusting unit 92 for adjusting the flow rate of the carrier gas, a thermal decomposition unit 93 for pyrolyzing the sample, a separation unit 94 for separating the sample, and a sample component. A detection unit 95 and an electrometer 96 that converts the detected value into data are provided, and these are connected in order from the upstream by a flow path.
When the sample is liquid, the sample is injected into the carrier gas flow from the sample injection port provided in the thermal decomposition unit 93. The sample is detected by the detection unit 95 and displayed as a pyrogram 97.

As the thermal decomposition unit 93, a heating furnace type, an induction heating type, and a filament type are known. FIG. 7 shows a schematic diagram of a heating furnace type, FIG. 8 shows an induction heating type, and FIG. 9 shows a filament type thermal decomposition part.
In the heating furnace type pyrolysis section shown in FIG. 7, a sample inlet 101 to the column of the gas chromatograph is provided at the lower end of the pipe 105. The pipe 105 is provided with a carrier gas introduction part 104, a thermal desorption / pyrolysis furnace 107, a cooling air inlet 106, and a heating part 102 in order from the top of the figure.
The sample is charged and dropped to the position of the thermal desorption / pyrolysis furnace 107, pyrolyzed by the heating unit 102, and sent to the gas chromatograph via the sample injection unit 101 by the carrier gas.

In the case of the induction heating type shown in FIG. 8, the sample injection unit 112 and the sample injection port 111 to the gas chromatograph are connected by a pipe 113, and an induction coil 114 is wound around the pipe 113 to insulate the heat. Covered with a cover. The pipe 113 is provided with a purge gas inlet 117, a sample holder 116, and a carrier gas introduction part 115.
The sample is wrapped in a ferromagnetic thin film and then placed in a sample tube (not shown). This sample tube is set in the sample holder 116 and induction heating is performed by high frequency. The sample thermally decomposed by the sample holder 116 is sent from the sample inlet 111 to the gas chromatograph by the carrier gas.

In the case of the filament type shown in FIG. 9, the pipe 122 is formed so as to be sandwiched between the heat retaining interfaces 121. A ribbon heater 123 is provided in the pipe 122. The pipe 122 is provided with a carrier gas flow port 124 and a sample injection port 125 for a gas chromatograph.
A sample is applied to the surface of the filament heater 126 and set in the ribbon heater 123. The sample is thermally decomposed by energizing and heating the filament heater 126, and sent to the gas chromatograph by the carrier gas from the carrier gas circulation port.

Super Purification Technology System Volume 1 Analysis Technology Supervision Toshiyuki Hoka Fuji Techno System, 1996, 886-888 Capillary gas chromatography Asakura Publishing, 1997, 85-88 S.A.Liebman and E.J.Levy, Marcel Dekker, Inc., Pyrolysis and GC in Polymer Analysis, CHROMATOGRAPHIC SCIENCE SERIES VOLUME29, (1985) 30-31 Shaelah Reidy, Gordon Lambertus, Jennifer Reece, and Richard Sacks, High-Performance Static-Coated Silicon Microfabricated Coloums for Gas Chromatography, Anal. Chem. 78 (2006) 2623-2630 S. Zimmermann, S. Wischhusen, J. M ・ ller, Micro flame ionization detector and micro flame spectrometer, Sens. Actuators B 63 (2000) 159-166

However, when connecting a pyrolyzer to a gas chromatograph, the piping to be connected becomes complicated as described above, and a dead volume is generated at the connection between the devices. Will fall.
Moreover, since the heat capacity of the thermal decomposition part is large and the decomposition of the sample is an endothermic reaction, a long time is required for analysis. Further, since the sample cannot be instantaneously decomposed, a secondary reaction or recombination of the sample may occur.

  Therefore, an object of the present invention is to provide a pyrolysis gas chromatograph apparatus with improved separation ability.

The present invention reduces the dead volume and reduces the heat capacity by reducing the number of connections between devices.
The pyrolysis gas chromatograph apparatus of the present invention includes a pyrolysis section that pyrolyzes a sample, a column that separates a sample guided from the pyrolysis section, and a detection section that detects sample components separated by the column. In the first embodiment, the pyrolysis section is a substrate in which a heating channel is formed and the sample is pyrolyzed in the heating channel, and the column has a separation channel formed in another substrate and a separation flow is formed. The sample is separated in the channel, and the thermal decomposition part and the column are laminated and integrated, and the heating channel and the separation channel are connected via the joint surface of both substrates.

In the second embodiment, the pyrolysis section, the column, and the detection section are laminated and integrated, and the pyrolysis flow path, the separation flow path, and the detection flow path are connected via the bonding surface of the substrate. It is.

  In order to prevent secondary reaction or recombination of the pyrolyzed sample, or to adjust the temperature of separation, a heating element is further formed on the substrate, and a temperature control unit for heating the column from the outside by the heating element is further provided. In this way, the temperature control unit may be laminated and integrated with the column.

  The flow path formed in each said board | substrate can be formed in a silicon substrate by an etching technique or shaping | molding, for example.

  When the heating temperature for the pyrolysis part and the column is different, a heat insulating material may be provided in a part of the periphery of the pyrolysis part, and the thermal decomposition part may be insulated from the column and the outside air by the heat insulating material.

  The thermal decomposition part can be formed of, for example, silicon, an inorganic silicon compound, a metal, or a composite material composed of two or more thereof. In that case, it can be used as a heating furnace type thermal decomposition section heated by energization by a power supply device connected via a conducting wire.

  The thermal decomposition part can be formed of a magnetic material. In this case, it can be used as a dielectric heating type thermal decomposition section that is heated by being subjected to a dielectric by a power supply device arranged in the vicinity of the magnetic body.

  The pyrolysis gas chromatograph apparatus of this invention can reduce a connection part and can reduce a heat capacity by integrating a pyrolysis part and a column. In addition, in the conventional apparatus, since the connection part between the pyrolysis part and the column cannot be heated, a cooling point is generated, which causes adsorption of the sample and causes a decrease in reproducibility. Thus, the generation of a cooling point can be prevented, and the measurement accuracy can be increased.

  If the pyrolysis section, the column, and the detection section are integrated, the capacity of the connection section is not required, so that the entire apparatus can be reduced in size.

  By integrating the column and the detection unit, the sample separated by the column can be measured immediately, peak tailing and the like are less likely to occur, and the sample can be measured more accurately.

  If a temperature control unit for heating the column is further provided, the sample can be separated at a desired temperature even when the apparatus is downsized. In addition, the pyrolysis step can be set to a temperature different from the separation step in the column.

  If a heat insulating material is provided around the pyrolysis section, the sample can be pyrolyzed while heat insulating from the column and outside air. Moreover, even if the cover has a function of a heat insulating material, it can be insulated from the outside air.

Examples of the present invention will be described below.
FIG. 1 is a schematic exploded perspective view showing an embodiment of a pyrolysis gas chromatograph apparatus.
The heating flow path 13 in the thermal decomposition part 11 is formed by bonding together a substrate 15 on which a groove is formed and a cover plate 16 that covers the groove from above. The cover plate 16 and the substrate 15 are formed with holes 18 and 19 for gas circulation. A heating device 17 for heating the sample is disposed around the heating channel 13.

  A heat insulating material 12 is formed in a region indicated by hatching on the surface of the thermal decomposition portion 11. Further, a heat insulating material is also formed on the back surface of the thermal decomposition portion 11. Examples of the heat insulating material 12 include porous silicon. One embodiment of the thermal decomposition section will be described with reference to FIGS. Further, the liquid sample is injected into the heating flow path 13 from the through hole 18 together with the carrier gas, and is thermally decomposed by the heating device 17.

  In the column 21, the separation channel 27 is formed between the substrates 25 and 23 by bonding the substrate 23 to the substrate 25 in which the grooves are finely processed. The substrate 23 is formed with holes 28 and 29 through which the sample flows. The separation channel 27 is formed in a spiral shape, for example. The sample pyrolyzed by the pyrolyzing unit 11 is introduced from the through hole 28 through the hole 19 of the pyrolyzing unit 11 and separated in the separation channel 27. One embodiment of the column is illustrated in FIG.

The detection unit 31 is formed by joining a cover plate 37 serving as a cover to a substrate 35 on which a groove serving as a detection flow path 33 is finely processed. The cover plate 37 has holes 30, 32, and 34 for gas distribution. Measuring devices such as an input amplifier, an attenuator, and a recorder are connected to the detection unit 31. It is preferable that the detection unit 31 can also be temperature-controlled from the outside. These configurations will be described later.
The detection unit 31 is an FID (hydrogen flame ionization detector), and a sample is ionized by hydrogen flame in the detection flow path 33 by the gas introduced from the holes 32 and 34, and then detected by the measurement device. One embodiment of the detection unit 31 will be described with reference to FIG.
As described above, the substrate 15 and the substrate 35 are laminated and integrated on the substrate 23, whereby one end of the separation channel 27 is connected to the thermal decomposition unit 21 and the other end is connected to the detection unit 31.

  Reference numeral 41 denotes a temperature control unit that adjusts the temperature of the column 21 from the outside, and is laminated and integrated with the column 21. This temperature control part 41 can be formed of a substrate, and the space of the column 21 is formed as a concave part. A heating element 43 is provided in the temperature control unit 41, and the heating element 43 can be heated by the power supply device 45. As the heating element 43, a heating furnace type, an induction heating type, a filament type, or the like used for the thermal decomposition unit 11 can be used.

In this embodiment, the pyrolyzing unit 11, the column 21, the detecting unit 31, and the temperature adjusting unit 41 are integrated by stacking the respective substrates, and a jig 51 serving as a lid is provided at the top. The jig 51 is provided with a carrier gas introduction port 53, an air introduction port 55, an H ₂ introduction port 57 and a gas discharge port 54 used for hydrogen flame ionization detection.
The heating flow path 13, the separation flow path 27, and the detection flow path 33 are connected via a surface in contact with the substrate. As a result, a dead volume due to the connection portion does not occur.
Moreover, since the column 21 is accommodated in the temperature control part 41 and the thermal decomposition part 11 and the detection part 31 can be arranged side by side, an apparatus becomes compact.

Next, the operation of this embodiment will be described.
As a sample, for example, 1 μg of ink (mixture of raw material and solvent) is put into the hole 18 and fixed with a jig 51. The carrier gas is flowed from the carrier gas inlet 53 at 1 mL / min, and the temperature of the column 21 is set to 50 ° C., and the temperature of the detector 31 is set to 250 ° C.

When an electric current is passed through the thermal decomposition unit 11 to 250 ° C., the solvent in the ink volatilizes instantaneously, and a chromatogram of the solvent is obtained on the display device (not shown) connected to the detection unit 31.
Next, after the pyrolysis gas chromatograph apparatus is cooled, the jig 51 of the pyrolysis section 11 is opened and TMAH (tetramethylammonium hydroxide) as a derivatization reagent is added a little, and then the jig 51 is fixed. The temperature of the thermal decomposition part 11 is made 500 degreeC, and a raw material is decomposed | disassembled. The decomposed sample is heated to 290 ° C. at a heating rate of 8 ° C./min, and kept at a constant temperature for 5 minutes to analyze the sample. A pyrogram of the pyrolysis product is obtained on the display unit connected to the detection unit 31.

Next, an example of the manufacturing process of the thermal decomposition part will be described.
FIG. 2 is a schematic view of a filament-type pyrolysis section. The manufacturing process of a board | substrate is shown in order of (A)-(H). (I) is a top view of the substrate, (J) is a bottom view of the substrate, and (K) is a top view of the cover plate that covers the substrate.
(A) Both surfaces of the silicon substrate 15 are thermally oxidized to form silicon oxide films 61 on the substrate surface.
(B) The silicon oxide film 61 is patterned by photolithography and etching techniques to form a silicon oxide film pattern 62.
(C) Anodization is performed on both surfaces of the silicon substrate 15 using the pattern 62 as a mask to form porous silicon 63. The porous silicon 63 is used as a heat insulating material.

(D) Next, a resist is applied, and a resist pattern 67 is formed using a photomask.
(E) The heating flow path 13 is formed by etching using the resist pattern 67 as a mask.
(F) The resist pattern 67 is removed, and a metal thin film to be the electrode 69 is formed in the heating channel 13 by sputtering.
(G) The substrate 15 and the cover plate 73 are previously formed with through holes 19 and 18 for circulating the sample in the flow path, and the cover plate 73 is joined to the substrate 15 on which the electrode 69 is manufactured.
(H) The electrode 69 is connected to the power supply device 17 so that the heating channel 13 can be heated by heat from the filament.

  FIG. 3 is a schematic view of a pyrolysis section of a dielectric heating type. The manufacturing process of a board | substrate is shown in order of (A)-(G). (H) is a top view of the substrate, (I) is a bottom view of the substrate, and (J) is a top view of the cover plate that covers the substrate. Steps (A) to (E), (I), and (J) are the same as those in the embodiment shown in FIG.

In the step (F), the magnetic thin film 70 is formed in the heating channel 13 by sputtering as a material to be dielectrically heated.
(G) On the substrate 15 and the cover plate 73, through holes 19 and 18 for circulating the sample through the heating channel 13 are formed in advance, and the cover plate 73 is placed on the substrate 15 on which the magnetic thin film 70 is formed. .
In the top view shown in (H), the magnetic thin film 70 is formed at a position to be the heating flow path 13. Note that Non-Patent Document 3 shows implementation conditions when heating using a ferromagnetic material such as the magnetic thin film 70.

Next, an example of the column manufacturing process will be described.
FIG. 4 is a schematic view of a column, showing manufacturing steps in the order of (A) to (G).
(A) to (B) A silicon oxide film 75 is formed on the surface of the substrate 25 by thermally oxidizing the surface of the silicon substrate 25.
(C) A silicon oxide film pattern 77 is formed by photolithography and etching techniques.
(D) Etching is performed using the pattern 77 as a mask to form a groove to be the separation channel 27.
(E) The separation channel 27 is formed by bonding the substrate 23 serving as a cover to the substrate 25 in which the grooves are formed.

(F) An inactive surface treatment is applied to the inner surface of the separation channel 27 so that the flowing sample gas does not adsorb.
(G) In order for the separation channel 27 to function as a column, a liquid phase coating 79 is applied to the inner surface of the channel 27.
An example of a column formed by finely processing a groove in a substrate as described above is shown in Non-Patent Document 4.

Next, an example of the manufacturing process of the detection unit will be described.
FIG. 5 is a schematic diagram of the detection unit, showing the manufacturing process in the order of (A) to (G). (H) is a top view of the cover plate, (I) is a top view of the substrate, (J) is a cross-sectional view of the quartz tube bonded to the top surface of the cover plate, and (K) is a cross-section in which a thin film is formed in the quartz tube. The figure is shown. Further, (L) is a perspective view in which a measuring device is connected to the detection unit 31.
Steps (A) to (D) in this embodiment are the same as steps (A) to (D) in the embodiment of FIG. 4, but in the step (D), the flow path shape to be the detection flow path 33 is changed. As shown in (I), the shape was divided into two forks. One end of the detection flow path 33 is an electrode 38.

In the step (E), the cover plate 37 in which the through hole 30, the air introduction hole 32, and the H ₂ introduction hole 34 are formed is joined to the substrate 35.
(F) A thin film electrode 79 is formed on the electrode 38 of the detection flow path 33. Next, a thin film electrode 83 as shown in (K) is formed inside the quartz tube 81 shown in (J).
In the step (G), the quartz tube shown in (K) is joined to the surface of the cover plate 37.

(L) is a perspective view of a state in which a measuring device is connected to the detection unit 31, and the electrode 38 is connected to the ground via a conducting wire, and the quartz tube 81 is connected to the input amplifier 84 via the conducting wire. An attenuator 85 and a recorder 86 (measuring device) are sequentially connected to the input amplifier 84.
An example of a detector formed by finely processing a groove on a substrate as described above is shown in Non-Patent Document 5.

In the embodiment of FIG. 1 described above, the pyrolysis unit 11, the column 21, the detection unit 31, and the temperature control unit 41 are stacked and integrated, but the present invention has only two of these stacked. In this case, for example, the case where only the thermal decomposition section 11 and the column 21 are stacked is included.

In the above-described embodiment, the column 21 is stacked on the temperature control unit 41, the pyrolysis unit 11 and the detection unit 31 are arranged side by side, and the jig 51 is further stacked thereon. Is not limited to this. For example, the pyrolysis unit 11 may be provided on one side of the column 21 and the detection unit 31 may be provided on the opposite side.
Further, the flow path shape of the column 21 is not limited to the spiral shape, and the detection unit 31 is not limited to the FID.

  The present invention can be used for gas chromatographs for measuring the concentration of components in various samples.

It is a general | schematic exploded perspective view which shows one Example of a pyrolysis gas chromatograph apparatus. It is the schematic of a filament-type thermal decomposition part. The manufacturing process of a board | substrate is shown in order of (A)-(H). (I) is a top view of the substrate, (J) is a bottom view of the substrate, and (K) is a top view of the cover plate that covers the substrate. It is the schematic of a thermal decomposition part of a dielectric heating type. The manufacturing process of a board | substrate is shown in order of (A)-(G). (H) is a top view of the substrate, (I) is a bottom view of the substrate, and (J) is a top view of the cover plate that covers the substrate. It is the schematic of a column, and has shown the manufacturing process in order of (A)-(G). It is the schematic of a detection part, and has shown the manufacturing process in order of (A)-(G). (H) is a top view of the cover plate, (I) is a top view of the substrate, (J) is a cross-sectional view of the quartz tube bonded to the top surface of the cover plate, and (K) is a cross-sectional view in which a thin film is formed in the quartz tube. Show. (L) is a perspective view in which a measuring device is connected to the detection unit 31. The schematic block diagram of the conventional gas chromatograph apparatus is shown. The schematic of the thermal decomposition part of the conventional heating furnace type | mold is shown. The schematic of the conventional induction heating type | mold thermal decomposition part is shown. 1 shows a schematic diagram of a conventional filament type.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Thermal decomposition part 12 Heat insulating material 13 Heating flow path 15 Board | substrate 16 Cover plate 17 Heating device 21 Column 23, 25 Board | substrate 27 Separation flow path 29 Through-hole 31 Detection part 33 Detection flow path 35, 37 Board | substrate 41 Temperature control part 43 Heating body 45 Power supply

Claims (4)

In a pyrolysis gas chromatograph apparatus comprising a pyrolysis section for pyrolyzing a sample, a column for separating a sample derived from the pyrolysis section, and a detection section for detecting a sample component separated by the column,
The thermal decomposition part is a substrate in which a heating channel is formed and the sample is pyrolyzed in the heating channel,
In the column, a separation channel is formed on another substrate, and the sample is separated in the separation channel.
The pyrolysis gas chromatograph apparatus, wherein the pyrolysis section and the column are laminated and integrated, and the heating flow path and the separation flow path are connected via a joint surface of both substrates. The detection section further detects a sample in the detection flow path in which a detection flow path is formed on another substrate,
The pyrolysis gas chromatograph according to claim 1, wherein the column and the detection unit are stacked and integrated, and the separation channel and the detection channel are connected via a joint surface between both substrates. 3. The heat according to claim 1, further comprising a temperature control unit that forms a heating element on the substrate and heats the column from the outside by the heating element, and the temperature control unit is laminated and integrated with the column. Decomposition gas chromatograph. The thermal decomposition according to any one of claims 1 to 3 , wherein a thermal insulation material is provided in a part of the periphery of the thermal decomposition unit, and the thermal decomposition unit is thermally insulated from the column and outside air by the thermal insulation material. Gas chromatograph device.

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