JPS59222764A - Gas chromatograph - Google Patents

Abstract

PURPOSE:To separate a plurality of components to be analyzed over a wide b.p. region with good efficiency within a short time, by passing low b.p. components through a column plural times by the change-over manipulation of a change- over valve. CONSTITUTION:When change-over valves 2a, 2b are held under a solid line connection state, a specimen quantitatively collected by a sample valve 1 is fed by carrier gas to reach the first column 3 through the valve 2a and a plurality of components A-D to be analized over a wide b.p. region as shown by the graph I are separated. Subsequently, the gas issued from a detector 4 is fed to the second column 5 through the valve 2b but the components having imperfect separation peaks in the graph I reach the column and, when the valves 2a, 2b are changed over to a broken line connection state before the component having a peak D reaches the valve 2b, the components having peaks A-C are again guided to the first column 3 through the column 5 and the valve 2a while the component having the peak C is perfectly separated as shown by the graphII. By repeating the above mentioned operation, a chromatogram, wherein the peaks of a plurality of components A-D over a wide b.p. region are perfectly separated, is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas chromatograph that collects a predetermined amount of a sample, transports it in a carrier gas, separates it in a separation column, and performs quantitative chromatographic analysis.

In such a gas chromatograph, analyte components in a sample are separated by a separation column, and each analyte component is eluted from the separation column in order of boiling point.

The elution time tended to be significantly longer than the difference in boiling point. For this reason, under normal analysis conditions in which the carrier gas pressure and the temperature of a separation force gym are kept constant, low boiling point components are poorly separated and high boiling point components are separated more than necessary.

The present invention has been made in view of these drawbacks.
The purpose is to provide a gas chromatograph that can efficiently separate multiple analyte components having a wide boiling point range in a short time.

The present invention is characterized by a gas chromatograph that collects a predetermined amount of a sample, transports it with a carrier gas, separates it in a separation column, and quantitatively analyzes it by chromatography. a detector for detecting the physical properties of the gas eluted from the column; a second column for capturing a desired specific component among the components guided from the detector; and a combination of the column, the first column, and the detector. First and second switching pulps are provided in between and connect the second column and the first column and the detector intermittently, and these pulps are switched in conjunction to switch the specific component from the first column to the first column. The column was passed through the column multiple times.

Below, the present invention will be explained in detail using figures. 1st
The figure is an explanatory diagram of the configuration of an embodiment of the present invention. In the figure, 1 is a sample pulp for taking a predetermined amount of the supplied sample and injecting it into the carrier gas line, 2a and 2b are interlocked with each other, and the solid lines in FIG. A switching valve 3 alternately switches between a connected state and a broken line connected state, and 3 is a first column into which a predetermined amount of sample collected from the sample pulp 1 is carried in via the switching valve 2a with a carrier gas, and the sample is separated. ,
4 is a detector for detecting, for example, the thermal conductivity of the gas eluted from the column 3; 5 is led out from the detector 4 and carried in via the 2-switch bower rep 2b, and captures the sample components in the gas; This is the second column.

In the embodiment of the present invention having the above configuration, the switching valves 2a and 2b are initially off, resulting in the solid line connection B in FIG. In this state, the sample valve 1 is turned on and a predetermined amount of the sample is collected. The sample is transported by a carrier gas to the first column 3 via the switching valve 2a,
For example, as shown in FIG. 2(a), a plurality of analyte components A to D having a wide boiling point range present in the sample are separated. The eluted gas from the column 5 reaches the detector 4 where, for example, the thermal conductivity is detected, and it is shown in Figure 2 (a) on a recorder or the like.
The romatogram is shown as follows. Gas led out from the detector 4 is conveyed to the second column 5 via the switching valve 2b. Before the components of the incompletely separated peaks A to C in FIG. 2(a) reach the second column 5 and before the component of peak D reaches the switching valve 2b, the switching valves 2a and 2b are turned on, as shown in FIG. Switch from the solid line connection state to the broken line connection state. Therefore, the components of peak D are vented through the switching valve 2b, and the components of peaks A to C are led back to the first column 5 via the second separation column 5 and the switching valve 2a, as shown in FIG. ), the components of pregnant beak C are completely separated. When the switching valves 2a and 2b are turned off at the same time that this C component starts to be detected by the detector 4, the components of peaks A and B are transferred to the second column 5 by the carrier gas via the first column 5 and the switching valve 2a. be returned. Immediately after the A and B components are transferred to the second column 5 (that is, immediately before the C component enters the second column 5), if the switching valves 2a and 2b are turned on again, the A and B components are turned on again.
, the B component enters the first separation column 3 three times and is completely separated as shown in Figure 2 (c). Therefore, from the detector 4 the result is shown in Figure 2). The detection signal of the romatogram is thus obtained. When this chromatogram signal is passed through a signal processing circuit (not shown) and only the peaks in the shaded area (in Fig. 2) are drawn on a recorder, the peaks of multiple analyte components A-D with wide boiling point regions are completely detected. It will be obtained as a separated chromatogram.

FIG. 3 is a configuration explanatory diagram illustrating another embodiment of the present invention. In the figure, the same symbols as in FIG. 1 are used with the same meanings, and redundant explanation will be omitted here.

Further, 6 is a third separation column that captures sample components in the gas derived from the detector 4, and 7 is a switching valve 2a, 2b.
8 is a blind plug that blocks one flow path of the switching valve 70, and 9a and 9b are capillaries each having a predetermined fluid resistance value. Column 101d: This is a timing column disposed between the capillary column 9b and the switching valve 2b to prevent air, etc. from diffusing and entering from the vent.

In the embodiment having the configuration shown in FIG. 3, as shown in FIG.
, C, E, and F are present in a plurality of samples. That is, in FIG. 3, a predetermined amount of sample collected by the sample pulp 1 is transported by a carrier gas, reaches the first separation column 3, and undergoes separation as shown in FIG. 4. Of the analyte components A-F that have undergone such separation, the total separation peak A,
The component D is exhausted through the following path: detector 4 → third column, long ram 6 → switching valve 7 → capillary column 9a → pen detector 4. In addition, the components of B, C, E, and F due to the incompletely separated pea separation state are as follows: Detector 4 → 3rd column 6 Switch valve → Switch pulp 7 → Switch pulp 2b → 2nd column
Column 5 → is extremely switched pulp 2a → first column 3
→Detector 4→6th force 4. It flows through the flow path shown in Figure 1: ram 6→switching pulp 7→capillary column 9a→bench. Therefore, the incompletely separated peak peak signal shown in FIG. 1 can be obtained. Embodiments of the present invention as detailed above and others
1...According to the example of Since it has a structure in which it passes through, it has the advantage that multiple analyte components having a wide boiling point range can be efficiently separated in a short time. Also,
Since the number of times a sample is passed through the same separation column can be changed depending on the analyte component in the sample, it is possible to use a column with a fixed length and eliminate the need for relative column lengths. There are some advantages to doing so. Furthermore, since the configuration allows confirmation of each analyte component in the first column 3,
, 2b (or 7) can be switched accurately.

A simple explanation is a diagram explaining the configuration of an embodiment of the present invention, FIG. 2 is a Durham diagram showing the separation state etc. in each separation column, FIG. 3 is a diagram showing 117 of another embodiment of the present invention, and FIG. 2 is a chromatogram showing the state in separation column 3.

Sample valve 7', 2a, 2b, 7...Switching knob,...Column, 4...Detector, 8...Blind plug,
9a.

Pirari column, 10...timing column.

Claims (1)

[Scope of Claims] (Li) A gas chromatograph in which a predetermined amount of a sample containing a component to be analyzed is collected and separated by transporting it to a separation column using a carrier gas, and the component is quantitatively analyzed by chromatography, in which the component is separated. a first column, a detector for detecting the physical properties of the gas eluted from the column 4, a second column for capturing a desired specific component among the components guided from the detector; The first and second switching valves are provided between the first column and the detector to intermittently connect the second column and the first column and the detector, and these valves are switched in conjunction with each other. (2) The gas chromatograph according to claim 1, wherein the physical property is thermal conductivity.