JPS63124937A - Method for stabilizing liquid level in icp emission analysis - Google Patents

Abstract

PURPOSE:To smoothly discharge a waste liquid and to stably maintain the liquid level in a chamber by dropping a surfactant to a drain part of at least a sub-tank at the time of an analysis. CONSTITUTION:A soln. sample is atomized by a nebulizer 4 and is sprayed into the chamber 2 at the time of the ICP (high frequency inductively coupled plasma) emission analysis. The atomized sample is subjected to the uniformization of particles and stabilization of gaseous flow in the chamber 2 and is then introduced into a plasma torch 6. On the other hand, the excess sample sticks to the inside wall of the chamber 2, drops along the wall surface and is stored from a drain part 2a into the sub-tank 10. The surfactant is adsorbed to the inside walls of the sub-tank 10 and a waste liquid pipe 14 and part thereof is diffused into the waste liquid when the surfactant is dropped from a storage tank 16 by slightly opening a valve 18 at the time of the analysis. As a result, the waste liquid is gradually discharged from the sub-tank 10 according to the amt. to flow into the drain part 2a. The liquid level in the chamber 2 is thus stabilized and the plasma torch is stabilized as well.

Description

Detailed Description of the Invention (a) Industrial Application Field The present invention relates to a method for stabilizing a liquid level stored in a chamber constituting a spray chamber in ICP (high frequency inductively coupled plasma) emission spectroscopy. .

(b) Prior art and its problems In general, in ICP emission spectrometry, a sample is atomized with a nebulizer and introduced into a chamber, where the atomized sample, which is homogeneous and stabilized, is guided to a plasma torch to emit plasma. Qualitative and quantitative analysis of elements contained in a sample is performed by spectroscopy of plasma light from the sample and measuring its light intensity.

In such lCP emission analysis, in order to stabilize the atmosphere and plasma within the chamber, it is necessary to maintain a constant volume within the chamber during analysis. Therefore,
Conventionally, as shown in Fig. 3, an inverted V-shaped sub-tank d is connected to the drain section of chamber a via a waste liquid pipe C, and this sub-tank d is installed at a predetermined height with respect to chamber a. While draining the excess liquid from the sub-tank d, the liquid level Q in the chamber a is always kept constant.

In addition, e is an air vent part of the sub-tank d, and f is a nebulizer for sample atomization.

Incidentally, since the sample to be analyzed is dissolved with various chemicals such as hydrochloric acid, sulfuric acid, and fluoric acid, chemically resistant materials such as Teflon are used for the waste liquid pipe C and the sub-tank d. However, such chemically resistant materials generally have poor hydrophilicity. Therefore, the waste liquid stored from the waste liquid pipe C to the sub-tank d is not gradually discharged from the sub-tank d, but when the accumulated amount of waste liquid exceeds a certain value, it becomes a lump g and flows out at once. Then, due to this influence, the liquid level σ in the chamber a fluctuates, and the fluctuation is transmitted to the plasma torch, causing fluctuations in the photometric intensity. As a result, problems such as inability to perform analysis with high accuracy have occurred.

The present invention has been made in view of the above circumstances, and is intended to maintain a stable liquid level in a chamber during analysis in ICP emission spectrometry, so that highly accurate analysis can be performed at all times. The purpose is to

(C) Means for Solving the Problems In order to achieve the above object, the present invention maintains a constant height of the liquid level stored in this chamber from the chamber constituting the spray chamber in 102 emission analysis. The surfactant is dripped into at least the drain portion of the sub-tank of a series of discharge paths leading to the waste liquid tank via the sub-tank provided for this purpose.

(D) Embodiment FIG. 1 is a block diagram showing an ICP emission differential device section for applying the method of the present invention. In the same figure, l is 1
02 Emission spectrometer, 2 is a chamber that constitutes a spray chamber, 4
6 is a plasma torch, and 8 is a high-frequency coil. Reference numeral 10 denotes an inverted V-shaped glass sub-tank, with an air vent part 10a provided at its upper part, and one end 10b of its lower part connected to a drain part 2a of the chamber 2 via a waste liquid pipe 12 made of Teflon. In addition, the other end 10c is connected to a waste liquid tank (not shown) via a waste liquid pipe 14 made of Teflon, and by installing this sub-tank lO at a predetermined height with respect to the chamber 2, the inside of the chamber 2 is The liquid level is kept constant.

16 is a storage tank in which a surfactant containing sodium alkylbenzenesulfonate 11 and the like is stored, and a dripping pipe 20 is connected from this storage tank 16 to a sub-tank l via an on-off valve I8.
It is inserted into the air vent part 10a of O.

Next, a liquid level stabilization method of the present invention using the above-mentioned device will be explained.

During ICP emission analysis, a solution sample is atomized by a nebulizer 4 and sprayed into the chamber 2 . The atomized sample is guided to the plasma torch 6 after the particles are made uniform and the airflow is stabilized within the chamber 2 .

On the other hand, the surplus sample in the chamber 2 adheres to the inner wall of the chamber 2, falls along the wall surface, and is stored in the sub-tank 10 from the drain part 2a of the chamber 2. When the accumulated amount increases, the waste liquid pipe 14 is
The liquid is discharged through the waste liquid tank (not shown).

In this case, conventionally, the sub-tank 10 and the waste liquid pipe 12.14
Because of its poor hydrophilicity, the waste liquid was not gradually discharged from the subtank IO, and when the accumulated amount of waste liquid exceeded a certain value, it flowed out all at once. Therefore, in the present invention, the valve 18 is slightly opened during analysis, and the storage tank 1 is
The surfactant is dropped into the sub-tank 10 from step 6.

This surfactant is adsorbed on the inner walls of the sub-tank 10 and the waste liquid pipe 14, and a portion of the surfactant is diffused into the waste liquid. Therefore, the surface tension of the waste liquid flowing through the subtank IO and the waste liquid pipe 14 is reduced. As a result, the waste liquid will be gradually discharged from the sub-tank IO according to the amount flowing into the drain part 2a of the chamber 2, and the liquid level in the chamber 2 will be stabilized without fluctuation, and as a result, the plasma The torch will also be stabilized.

In the above embodiment, the surfactant was dripped from the air vent part 10a of the sub-tank 10, but as shown in FIG. A surfactant may be dropped onto the drain portion 10c.

(B) Effects As described above, according to the present invention, in ICP emission spectroscopy, surfactant is dripped at least into the drain part of the sub-tank during analysis, so that waste liquid is smoothly discharged and always remains in the chamber. The liquid level of the liquid will be kept stable, resulting in excellent effects such as being able to perform highly accurate analysis.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the present invention, and FIG. 3 shows a conventional example, and each of FIGS. 1 to 3 is a configuration diagram showing a part of an ICP emission spectrometer. 1... ICP emission spectrometer, 2... Chamber, lO
...Subtank, I2.14...Waste liquid pipe, 16...
Reservoir.

Claims (1)

[Claims] (1) At least in the drain section of the sub-tank in a series of discharge passages from the chamber that constitutes the spray chamber to the waste liquid tank via the sub-tank provided to maintain a constant level of the liquid level stored in this chamber. A method for stabilizing a liquid level in ICP emission spectroscopy, which comprises dropping a surfactant onto a liquid.