JP3098606B2 - Heat vaporization introduction method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for measuring a trace metal in a sample using an analyzer such as a high frequency inductively coupled plasma analyzer (hereinafter referred to as ICP-MS). And, in particular, a method for introducing high-temperature metal vapor evaporated in a heating vaporization chamber by mixing fine particles in a carrier gas so as to be efficiently introduced into an ICP-MS or the like. About.

[0002]

2. Description of the Related Art FIG. 2 is a structural explanatory view for explaining a conventional example of a heating vaporization introducing method. In this figure, a cuvette 3 is provided in a heated vaporization chamber 2, and the cuvette 3 is connected to a power supply for a heated vaporization furnace (not shown). When this power supply is turned on, a current flows through the cuvette 3 and heat is generated by Joule heat.

The temperature of the cuvette 3 can be arbitrarily adjusted by controlling the current supplied to the cuvette 3 and the applied voltage. In addition, a depression is provided in the center of the cuvette 3 so that a sample is accommodated in the depression. On the other hand, a carrier gas made of, for example, argon gas is introduced into the heated vaporization chamber 2 from the carrier gas inlet 1. The gas thus introduced is supplied to the heating vaporization chamber 2
Then, it is introduced into the inner chamber 4a of the plasma torch. Such a flow of the carrier gas serves to send the component to be measured from the heated vaporization chamber 2 to an analyzer such as an ICP-MS.

[0004]

However, in the above-mentioned conventional example, high-temperature metal vapor is active, and when the metal vapor comes into contact with the wall surface of the heating vaporization chamber 2 or the inner wall of the sample introduction tube 5, these wall surfaces and The element to be measured is adsorbed on the inner wall. As a result, the connection tube 5
The amount of the element to be measured that reaches the inner chamber 4a of the plasma torch through the passage decreases, and the analysis value of the element to be measured obtained by an analyzer such as an ICP-MS includes a large error. The sensitivity was reduced.

Further, it is considered that a difference occurs in the behavior of the vaporized element to be measured even when the amount of the element to be vaporized in the heating vaporization chamber 2 is large or small. The measurement sensitivity was changed due to the difference in the concentration of the element to be measured, and as a result, the linearity of the analysis value was also deteriorated. The present invention has been made in view of the above-described drawbacks of the conventional example, and has as its object to reduce the amount of the element to be measured adsorbed on the wall surface of the heating vaporization chamber and the inner wall of the connection tube, and to reduce the amount of IC.
It is an object of the present invention to provide a method for introducing heat vaporization, which enables a trace amount of metal element to be accurately analyzed by an analyzer such as a P-MS.

[0006]

SUMMARY OF THE INVENTION The present invention provides an ICP-MS
In a heating vaporization introduction method of vaporizing and introducing a sample into a sample when measuring a trace metal in a sample using an analyzer such as the above, the fine particles are diffused and mixed into a carrier gas in a particle generation chamber, and the fine particles are contained. The carrier gas is introduced into the heated vaporization chamber, and a small amount of high-temperature metal vapor generated by evaporation of the sample in the heated vaporization chamber comes into contact with the fine particles, and the fine particles become nuclei and condense or react to become inert particles. This problem has been solved by a configuration in which the active particles are transported by a carrier gas to the analyzer through the connection tube.

[0007]

The present invention operates as follows. That is, a sample is previously mounted on the cuvette in the heating vaporization chamber, and when the power supply for the heating vaporization chamber is turned on, a current flows through the cuvette and heat is generated by Joule heat. For this reason, the sample mounted on the cuvette is heated and evaporates. A small amount of high-temperature metal vapor generated by evaporation of the sample in this way
The fine particles come into contact with the fine particles introduced into the heating and vaporizing chamber, and the fine particles serve as nuclei to condense or react to become inert particles. The trace amount of inactivated metal is transported from the heated vaporization chamber to the inner chamber of the plasma torch through the connection tube by the carrier gas, and analyzed by an analyzer such as ICP-MS.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a view for explaining an embodiment of the present invention. In the figure, the same symbols as those in FIG. 2 are used with the same meanings, and duplicate explanations are omitted. 6 is a heating vaporization chamber 2
A particle generation chamber 7 is provided separately from the particle generation chamber 7, a particle insertion lid that covers the particle injection port of the particle generation chamber 6, and 8 has a particle diameter of 1 μm or less, such as carbon black or polyimide, generated in the particle generation chamber 6. The take-out port 9 is a capillary tube for guiding the carrier gas into the particle generation chamber 6.

In the embodiment of the present invention as shown in FIG. 1, first, a fine particle input lid 7 is opened, a predetermined amount of fine particles are put into the fine particle generation chamber 6, and then the fine particle input lid 7 is closed. Next, for example, 700 ml / min. From the carrier gas inlet 1 through the capillary tube 9. The carrier gas is supplied into the fine particle generation chamber 6 at a flow rate of?, And the fine particles in the fine particle generation chamber are dispersed. The fine particles dispersed in the fine particle generation chamber 6 in this manner are diffused and mixed with the carrier gas, and then guided to the heated vaporization chamber 2 from the outlet 8.

On the other hand, a sample is previously mounted on the cuvette 3 in the heating and vaporizing chamber 2, and when a power supply for the heating and vaporizing chamber (not shown) is turned on, a current flows through the cuvette 3 and heat is generated by Joule heat. For this reason, the sample mounted on the cuvette 3 is heated and evaporates.

The small amount of high-temperature metal vapor generated by evaporating the sample in this way comes into contact with the fine particles introduced into the heating and vaporizing chamber 2 as described above, and the fine particles become nuclei and condense. It reacts and becomes inert particles. The trace amount of metal that has become inactive in this way is transported by the carrier gas from the heated vaporization chamber 2 to the inner chamber 4a of the plasma torch through the connection tube 5, and analyzed by an analyzer such as an ICP-MS. . The present invention can be variously modified without being limited to the above-described embodiment.

[0012]

According to the present invention as described in detail above, when a trace metal in a sample is measured using an analyzer such as an ICP-MS, heat vaporization is introduced by vaporizing the sample into the analyzer. In the method, fine particles are diffused and mixed into a carrier gas, and the fine particles serve as nuclei to condense or react with a minute amount of high-temperature metal vapor in a heating vaporization chamber to form inert particles. There is an advantage that adsorption to the wall surface of the vaporization chamber and the inner surface of the connection tube can be reduced.

Therefore, according to the present invention, the amount of the element to be measured adsorbed on the wall surface of the heating vaporization chamber or the inner wall of the connection tube is reduced, and even a trace amount of metal element can be accurately analyzed by an analyzer such as ICP-MS. A possible heating vaporization introduction method is realized.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a configuration of an embodiment of the present invention.

FIG. 2 is a diagram illustrating the configuration of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Carrier gas inlet 2 Heated vaporization chamber 3 Cuvette 4 Plasma torch 5 Sample introduction tube 6 Particle generation chamber 7 Particle input lid 8 Outlet 9 Capillary tube

Claims (1)

(57) [Claims] 1. A heating vaporization introducing method for vaporizing and introducing a sample into a sample when measuring a trace metal in the sample using an analyzer such as a high frequency inductively coupled plasma analyzer,
The fine particles are diffused and mixed with the carrier gas in the fine particle generation chamber,
The carrier gas containing the fine particles is guided to a heated vaporization chamber, and a small amount of high-temperature metal vapor generated by evaporating a sample in the heated vaporization chamber comes into contact with the fine particles, and the fine particles become nuclei and condense or react. A method for introducing heat and vaporization, wherein inert particles are formed, and the inert particles are conveyed to the analyzer through a connection tube by the carrier gas.