JPH0237537B2 - KAGAKUHATSU KOBUNSEKIKEI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a chemiluminescence spectrometer that reacts a sample gas and a reagent gas to produce chemiluminescence, thereby measuring a component to be measured in the sample gas.

Conventional analyzers of this type, as shown in Figure 1,
A sample gas inlet 2, a reagent gas inlet 3, and a gas outlet 4 are provided on the tube wall of a reaction tube 1 having a circular cross section.
A photodetector 5 is provided adjacent to the reaction tube 1, and sample gas and reagent gas are introduced through the sample gas inlet 2 and reagent gas inlet 3 to cause a reaction, and then the gas is discharged through the gas outlet 4. The chemiluminescence during the reaction is detected by a photodetector 5 to measure the component to be measured in the sample gas.

That is, a method is used in which light is emitted at a predetermined location and the amount of light emitted is detected.

It is an object of the present invention to make it possible to easily eliminate the interference effects caused by interference components and to measure multiple components by considering a new viewpoint that has not been considered in the past.

That is, the chemiluminescence has the property that the luminescence timing differs depending on the reactant, and the present invention was made by focusing on this property of chemiluminescence, and the reaction tube is formed into an elongated shape along the gas flow path. The present invention is characterized in that the disturbing influence of interference components is removed and multi-component measurements are performed due to differences in light emission positions.

Embodiments of the present invention will be described below based on the drawings.

In FIG. 2, reference numeral 11 denotes a reaction tube (made of glass, for example) of a chemiluminescence analyzer, which has a sample gas inlet 12 and a reagent gas inlet 13 at one end, and a gas outlet 14 at the other end. And this reaction tube 1
1 has an elongated shape (for example, length l=250 mm) along the gas flow path.
15 is a photodetector that scans along the gas flow path of the reaction tube 11. Therefore, when the sample gas is introduced through the sample gas inlet 12 and the reagent gas is introduced through the reagent gas inlet 13, and the gas is discharged from the gas outlet 14, the components in the sample gas and the reagent gas are mixed in the reaction tube 11. The components react with each other to emit chemiluminescence, which is detected by the photodetector 15.

By the way, as mentioned above, chemiluminescence has different luminescence timing depending on the reactant, so those with an early luminescence time are, for example, at position b in Figure 1, and those with a late luminescence time are, for example, at position b in Figure 1. Light is emitted at position a, and detected by the photodetector 15 at that position.

Therefore, for example, if the luminescence timing of the component A to be measured is late and the luminescence timing of the interference component B is early, the interference effect of the interference component B can be suppressed by detecting the luminescence at the a position with the photodetector 15. , it will be understood that the concentration of the component A to be measured can be measured without being affected.

Also, of course, if it is in position b, component B
can be measured.

Figure 3 is a graph of experimental data showing that there are differences in luminescence timing depending on the type of reactant. In the figure, the horizontal axis represents the position of the reaction tube (length 250 mm), and the vertical axis represents the light emission The outputs of the detectors are shown respectively, where A shows the light emission due to hydrogen sulfide (H ₂ S) in the sample gas, and B shows the light emission due to nitric oxide (NO) in the sample gas. The flow rate of the sample gas is 400c.c./min, and the flow rate of the reagent gas (in this case ozone gas) is 340c.c./min.
It was set as min.

As you can see from this graph, by using a 250 mm reaction tube and detecting the light emission at a position 20 mm from one end (the side where the sample gas and reagent gas inlets are located) with a photodetector, it is possible to eliminate the need for a filter. H ₂ S can also be measured without interference from NO.

Note that the slowness of the light emission timing varies depending on the flow rate of the gas in the reaction tube 11, so the flow rate of the gas in the reaction tube 11 is adjusted as appropriate depending on the component to be measured and the type of interference component. (e.g. reduce the pressure and increase the flow rate).

Further, as can be easily inferred from the above embodiments, the present invention can also be implemented as a multi-component meter. That is, not only component A but also component B can be measured. Next, FIGS. 4A and 4B show a second embodiment of the present invention. In this embodiment, the reaction tube 11 is formed into a substantially annular shape, and a reflecting mirror 17 that rotates around an axis 16 is provided at the center of the annular reaction tube 11. The feature is that scanning is performed by

Next, FIGS. 5A and 5B show a third embodiment of the present invention. In this embodiment, a reaction tube 11 and a photodetector 1 are formed in an annular shape, similar to those in FIG.
A chipper 19 having a window 18 partially opened is provided between the chip 5 and the chip 5, and scanning is performed by rotating the chipper 19.

In each of the above embodiments, the measurement accuracy can be further improved by further providing an optical filter in the photodetector 15.

Next, in the embodiment shown in FIG. A plurality of optical filters 20 in between,
A disc body 23 with 21 and 22 is provided,
The rotation of the reflecting mirror 17 and the rotation of the disk body 23 are synchronized, so that multiple components (three components in this illustrated example) can be measured with high precision.

It goes without saying that the optical filters 20, 21, and 22 are arranged according to the chemiluminescence (peak) position of each component to be measured.

The present invention has the above-mentioned configuration, and the reaction tube is made into an elongated shape along the gas flow path, and the interfering influence of interference components is removed or multi-component measurement is performed by the difference in the light emission position caused by the difference in the light emission timing. Even if the emission wavelength spectra of the component to be measured and the interference component are close to each other, it is possible to eliminate the interference effects of the interference component, and furthermore, a multi-component meter can be realized with a very simple configuration. There is an effect.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing a conventional example, Fig. 2 is an explanatory diagram showing an embodiment of the present invention, Fig. 3 is a graph showing that the timing of chemiluminescence differs depending on the substance, and Fig. 4 A and B are A plan view and a partially cutaway front view showing another embodiment of the present invention, FIGS. FIG. 7 is a partially cutaway front view and a plan view of essential parts showing still another embodiment of the present invention. 11...Reaction tube, 12...Sample gas inlet, 13
...Reagent gas inlet, 14...Gas outlet.

Claims (1)

[Claims] 1. A sample gas inlet and a reagent gas inlet are provided at one end of the reaction tube, and a gas outlet is provided at the other end, and the reaction tube is formed into an elongated shape along the gas flow path,
A chemiluminescence analyzer configured to detect the amount of luminescence at a predetermined distance from one end of a reaction tube.