JP3177425B2 - Chemiluminescence analyzer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a chemiluminescence analyzer.

[0002]

2. Description of the Related Art In a chemiluminescence analyzer, a sample gas and an ozone gas are introduced into a gas flow path formed in a reaction tank to cause a luminescence reaction, and the light is detected by a photodiode (light detection sensor), thereby obtaining a sample. It is configured to perform gas component analysis.

In such a chemiluminescence analyzer, the collision angle between the sample gas and the ozone gas in the reaction tank and the diameter of the gas flow path are specified in order to increase the sensitivity, and the analysis accuracy is improved. In some cases, the gas flow path leading to the exhaust is formed in a maze so that the sample gas and the ozone gas stay longer in the reaction tank after the collision. For example, Japanese Patent Publication No. 2-11100 discloses an example of such a conventional chemiluminescent cell.

[0004]

However, all of the above-mentioned conventional chemiluminescence analyzers have a relatively small reaction volume, so that the luminescence reaction is not completed before exhaustion, and so-called out-of-system luminescence occurs. There have been problems such as generation of span noise in a high density range and reduction in linearity of measured values.

The present invention has been made in view of such circumstances,
It is an object of the present invention to provide a high-sensitivity chemiluminescence analyzer that eliminates out-of-system light emission, has less occurrence of span noise in a high-concentration range, and has less linearity of measured values.

[0006]

According to the present invention, means for solving the above-mentioned problems are constituted as follows. That is, the confluence of the sample gas introduction path and the ozone gas introduction path is set to a position that coincides with the center position of the sensor on the detector side on the reaction tank, and a labyrinth that expands outward from the junction. The groove at the junction is formed shallower, the groove is formed deeper toward the outer periphery, and a discharge path is connected to the groove at the outer peripheral portion.

[0007] As described above, the junction where the sample gas and the ozone gas react most often coincides with the center point of the sensor and the groove at the junction is made shallow, so that high sensitivity can be obtained. By forming the grooves communicating with each other deeper toward the outer periphery, the reaction volume can be set large, the luminescence reaction of the sample gas and the ozone gas can be completed in the grooves, and the light emission outside the system can be eliminated. Even in the density range, the occurrence of span noise can be suppressed low, and the linearity of measured values can be improved.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the chemiluminescence analyzer of the present invention will be described below in detail with reference to the drawings.
FIG. 1 is a longitudinal sectional view of a chemiluminescence analyzer, and FIG. 2 is a plan view of the reaction tank. In these figures, reference numeral 1 denotes a reaction tank.
11 is a main body (made of a synthetic resin material or the like), 12 is a casing, 2 (21 to 23) are maze-shaped grooves formed on the upper part of the main body 11, 3 is a sample gas introduction path, 4 is an ozone gas introduction path. Reference numeral 5 denotes a junction of the two introduction paths 3 and 4, and reference numeral 6 denotes a discharge path.

The junction 5 is provided such that its center position coincides with the center point of the light receiving surface of a photodiode (sensor) 8 provided in a detector 7 mounted on the reaction tank 1. The groove 2 is formed shallow at its junction 5;
The groove 2 is formed in a rectangular maze shape extending outward from the junction 5 and the groove 2 is formed deeper toward the outer periphery,
The reaction volume is set large.

The above-mentioned groove 2 has a rectangular light receiving surface (10 mm × 10 mm) of the photodiode 8 through an optical window 9 provided in close contact with the upper surface of the main body 11 of the reaction tank 1 via an O-ring 10.
10 mm), and the outer circumference of the groove 2 is set to be slightly smaller than the outer circumference of the light-receiving surface, so that all light emission reactions in the groove 2 can be detected without leakage. In addition,
13 is a Peltier element for cooling the photodiode.

The sample gas introduction path 3 and the ozone gas introduction path 4 are set at a collision angle (for example, 120 °) at which a luminous reaction can be caused most efficiently, and the junction 5 is formed shallowly. Light emitted at the central point of the photodiode 8 can be efficiently detected, and high sensitivity can be obtained.

The gas after the collision reacts to emit light while gradually moving toward the outer periphery of the groove 2 formed in a maze shape, and the outermost peripheral groove 23
Since a sufficient reaction volume is secured from the flow path to the discharge path 6, all the reactions can be completed in the groove 2. Therefore, out-of-system light emission can be prevented, the occurrence of span noise can be reduced even when the concentration of the sample gas is high, and the linearity of the measured value can be ensured. Obtainable.

For example, the size of the light receiving surface is 10 mm × 10 mm
In the rectangular photodiode 8, the main body 1 of the reaction tank 1 is
The depth of the grooves 2 formed in each of the grooves 1 is 0.8
mm, the groove 22 is 1.4 mm, the groove 23 is 2.8 mm,
When the volume (reaction volume) of the groove 2 is 176.6 mm ³ , the sample gas (10 ppm to 10,000 p
pm) 90 ml / min, ozone gas 380 ml / mi
Under the conditions of n and the flow rate of the dilution gas ml / min, generation of span noise was not recognized. In the conventional type having a relatively small reaction volume (50 mm ³ or less), considerable span noise was generated. For reference, FIG. 3A shows the sample gas concentration of the chemiluminescence analyzer of the present invention of 4,790 ppm.
(B) shows the instruction data at the same density in the conventional type.

Incidentally, regarding the luminescence reaction in the reaction tank 1, for example, in the case of a NO meter, NO and O ₃ collide with each other and become excited (NO + O ₃ → NO ₂ ^* + O ₂ ). Emit light when returning to state (NO ₂ ^*
→ NO ₂ + hν), and the light is detected by the photodiode 8. As an analyzer that can utilize such a luminescence reaction, there are a C ₂ H ₄ meter, an O ₃ meter, an H ₂ S meter and the like in addition to the NO meter.

[0015]

As described above, according to the chemiluminescence analyzer of the present invention, the confluence of the sample gas and the ozone gas coincides with the center point of the sensor, and the groove at the confluence is made shallow, so that it is most active. The reaction volume can be detected efficiently and high sensitivity can be obtained.Moreover, since the groove communicating in a maze shape is formed deeper toward the outer periphery, the reaction volume can be set large, and the sample gas and the gas in the groove can be set. Ozone gas emission reaction can be completed, out-of-system light emission is eliminated, span noise is less generated even in a high concentration range, linearity of measured values can be improved, and highly reliable analytical values can be obtained. Can be. Note that the groove of the present invention may be circular in plan view, and its shape is not limited.

[Brief description of the drawings]

FIG. 1 is an AOB longitudinal sectional view showing an example of an embodiment of a chemiluminescence analyzer of the present invention.

FIG. 2 is a plan view of the reaction tank.

FIG. 3 (A) shows instruction data at a sample gas concentration of 4,790 ppm (full scale) of the chemiluminescence analyzer of the present invention, and FIG. 3 (B) shows instruction data of the same concentration of a conventional chemiluminescence analyzer.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Reaction tank, 2 (21-23) ... Groove, 3 ... Sample gas introduction path, 4 ... Ozone gas introduction path, 5 ... Confluence point, 6 ... Discharge path, 7 ... Detector, 8 ... Sensor.

Claims (1)

(57) [Claims] 1. A junction point between a sample gas introduction path and an ozone gas introduction path is set to a position coincident with a center position of a sensor on a detector side on a reaction tank, and outward from the junction point. A chemiluminescence analyzer characterized in that a maze-shaped groove is provided, the groove at the junction is formed shallower, the groove is formed deeper toward the outer circumference, and a discharge path is connected to the groove at the outer circumference.