JPH10307121A - Mass specfrometer for gas chromatograph - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a structure and to reduce manufacturing costs by connecting an ionization container and a column for separating samples and at the same time connecting a capillary for interdicting a reaction gas halfway to a column edge part, mixing the sample with the reaction gas and introducing the mixture into the ionization container. SOLUTION: An ionization container 2 for introducing a sample gas being separated by a gas chromatograph is provided in a vacuum container 1, and a column edge part 3a of a capillary column 3 is connected to a hole 2a of the ionization container 2. Further, a capillary 5 for introducing a reaction gas to the ionization container 2 is connected to the column edge part 3a. Then, the ionization container 2 merges the capillary 5 halfway to the column edge part 3a of the capillary column 3 from a gas chromatograph and simultaneously introduces a sample that is separated from the capillary column 3 and the reaction gas into the ionization container 2. Then, a sample molecule is ionized by collision in an electron flow in the mixed gas state between the separated sample and the reaction gas, which is recorded and analyzed as a mass spectrum.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a mass spectrometer for a gas chromatograph, and more particularly to a mass spectrometer for a gas chromatograph in which an ionization container for chemical ionization in a vacuum container is improved.

[0002]

2. Description of the Related Art A mass spectrometer is used as a gas chromatograph detector for performing qualitative / quantitative analysis from a mass spectrum of a sample component. In a mass spectrometer using the chemical ionization method, a sample separated by a gas chromatograph and a reaction gas are introduced into a vacuum vessel, and the reaction gas is bombarded with an electron flow to ionize the sample molecules. Record and analyze as a spectrum. As shown in FIG. 3, such a gas chromatograph mass spectrometer has a configuration in which an ionization container 12 serving as an ion source, a lens 13, a mass filter 14, a detector 15, and the like are arranged in a vacuum container 11. I have.

[0003] The ionization vessel 12 serving as the ion source includes:
As shown in FIG. 2, it is placed in a high vacuum vessel 11 of about 10 ^-5 to 10 ^-6 torr, and the internal pressure is set to 1 by the reaction gas.
0 ^-1 a container is about to 10 ^-2 torr, the sample separated by capillary column 3 of the gas chromatograph to the ionization chamber 12 is introduced from its end 3a, connecting the capillary 16 to a different position The structure is such that a reaction gas is introduced from outside the vacuum vessel 11.

[0004]

As described above, the ionization container 12 of the mass spectrometer has a hole 11a and a hole 12a in the vacuum container 11 and the ionization container 12 in the vacuum container 11 for connecting the thin tube 16, respectively. It will be drilled.
As described above, since the vacuum vessel 11 and the ionization vessel 12 require a relatively high degree of vacuum, great care must be taken in connecting the piping, and processing and maintenance are complicated. In addition, the cost is high due to the complicated structure.

SUMMARY OF THE INVENTION The present invention has been made to address the above-mentioned problems, and provides a mass spectrometer for a gas chromatograph which has a relatively simple structure, can be easily maintained, and can be manufactured at a reduced cost. It is an object.

[0006]

That is, in order to solve the above-mentioned problems, the present invention arranges an ionization container (2) in a vacuum container (1) and reacts with a sample in the ionization container (2). In a gas chromatograph mass spectrometer to which a gas is introduced, the ionization vessel (2) is connected to an end (3a) of a sample separation column, and a reaction gas is provided in the middle of the column end (3a). A thin tube (5) for introduction is connected, and a sample and a reaction gas are mixed and introduced into the ionization container (2).

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a configuration around an ionization container in a vacuum container constituting a mass spectrometer for a gas chromatograph of the present invention. In the vacuum vessel 1, an ionization vessel 2 for introducing a sample gas separated by gas chromatography is arranged. The ionization vessel 2 is provided with a hole 2a, and the hole 2a has a column end 3 of a capillary column 3 of a gas chromatograph.
a is connected. Further, a thin tube 5 for introducing a reaction gas, for example, methane, isobutane, ammonia or the like into the ionization vessel 2 is connected to the column end 3a. In this case, for example, the capillary column 3, the column end 3a and the thin tube 5 may be connected by using a connector 4 having a three-way passage, or the merging conduit may be a conduit forming a three-junction.

That is, in the ionization vessel 2 in the vacuum vessel 1 of the gas chromatograph mass spectrometer, a thin tube 5 for introducing a reaction gas is merged in the middle of the column end 3a of the capillary column from the gas chromatograph. The separated sample and the reaction gas are simultaneously introduced into the ionization container 2. Then, the introduced sample molecules are ionized by bombardment with an electron flow in a mixed gas state of the separated sample and the reaction gas, and the ionized sample molecules are recorded as a mass spectrum and analyzed.

As described above, the narrow tube 5 for introducing the reaction gas is merged into the ionization container 2 in the vacuum container 1 in the middle of the column end 3a of the capillary column. As shown, a hole 11a for passing a conduit 16 for a reaction gas through the vacuum vessel 11 and a vessel 12 in the vacuum vessel 11 and a hole 12a for introducing a reaction gas into the vessel 12 are provided.
It is not necessary to provide. Usually, since the inside of the vacuum vessel 11 and the vessel 12 is set to a high vacuum state, the fitting between the vacuum vessel 11 and the pipe 16 and the joining between the vessel 12 and the pipe 16 require close attention, According to the structure of the present invention, it is not necessary to drill these holes 11a and 12a.

The ionization of the sample is performed by the ionization vessel 2
The reaction is performed after mixing the sample gas and the reaction gas with each other, so that the sample gas and the reaction gas may be separately introduced into the ionization container 12 as in the related art, or the sample gas and the reaction gas may be mixed as in the present invention. There is no difference in the ionization reaction itself even if mixed and then introduced into the ionization vessel 2. Accordingly, the vacuum vessel 1 of the mass spectrometer of the present invention and the ionization vessel 2 in the vacuum vessel 1 do not require two holes for the reaction gas pipe, so that the number of processing steps can be reduced. In addition, maintenance becomes easier.

[0011]

As described in detail above, according to the gas chromatograph mass spectrometer of the present invention, it is possible to reduce the number of holes required to form a vacuum vessel and a vessel serving as an ionization chamber in the vacuum vessel. The structure becomes simple and maintenance becomes easy. Further, since the number of processing steps can be reduced, the cost can also be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration around an ionization container in a vacuum container constituting a gas chromatograph mass spectrometer of the present invention.

FIG. 2 is a diagram showing a configuration around a ionization container in a vacuum container constituting a conventional gas chromatograph mass spectrometer.

FIG. 3 is a diagram showing an outline of a configuration of a gas chromatograph mass spectrometer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vacuum container 2 Ionization container 3 Capillary column 3a Column end 4 Connector 5 Thin tube

Claims (1)

[Claims] 1. A gas chromatograph mass spectrometer in which an ionization container is disposed in a vacuum container and a sample and a reaction gas are introduced into the ionization container, wherein the ionization container and an end of a sample separation column are provided. A mass spectrometer for a gas chromatograph, wherein a thin tube for introducing a reaction gas is connected in the middle of the column end, and a sample and a reaction gas are mixed and introduced into the container. .