JPH02253139A - Sample introducing method for inductively coupled plasma emission spectrophotometer - Google Patents

Abstract

PURPOSE:To shorten the time required for substitution of a sample and to make an analysis with a small amt. of the sample by introducing the fresh sample into an atomizing chamber, then opening a drain cock to discharge the fresh sample diluted with the already analyzed sample in a sample well. CONSTITUTION:The drain cock 1e is opened while a selector cock 5 is held set in a circulation position after the end of a certain analysis to discharge the sample in the sample well 1d as well as to discharge the sample in the tube from the sample well 1d to the cock 5 and the sample from the cock 5 to a nebulizer 2 into the atomizing chamber 1. The cock 5 is then selected at the introduction position to introduce the fresh sample into the atomizing chamber to substitute the sample in the tube from the sample well to the cock 5, the sample in the tube from the cock 5 to the nebulizer 2 and the sample sticking on the inside wall of the nebulizer 2 as well as the sample sticking on the inside wall of the atomizing chamber 1 with the fresh sample. The cock 1e is thereafter opened to discharge the fresh sample diluted with the already analyzed sample. While the cock 5 is held selected at the introduction position, the fresh sample is introduced and thereafter, the cock is selected at the circulation position and the analysis is started after plasma stabilizes.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to high-frequency inductively coupled plasma emission spectroscopy (I
CP-AES), and particularly relates to a circulating sample introduction method.

[Prior art I I The sample introduction device for CP-AES consists of a nebulizer, a spray chamber, and a torch tube.The nebulizer atomizes the sample, and the spray chamber sorts the sample mist into particles with small particle sizes (
(classification effect) and is introduced into the plasma via the torch tube.

At this time, due to the classification effect in the spray chamber, only about 5% of the sample introduced into the nebulizer is introduced into the plasma through the torch tube, and the remaining 95% is discharged from the spray chamber without being used for analysis. be done. For this reason, analysis required about 20 times as many samples as were actually introduced into the plasma.

Therefore, in order to reuse the discarded sample, a new sample is introduced into the nebulizer from the sample reservoir and the outside (introduction).
An attempt was made to introduce a discarded sample into the nebulizer again (circulating sample introduction) by installing a switch cock to switch between introducing the sample from the sample reservoir into the nebulizer (circulation). ).

Conventionally, when replacing an analysis sample, the following sequence was used (here, when a certain analysis is performed, the switching cock is in circulation, the drain cock is closed, and the analysis is completed). Assume that the state remains the same at the time of

First, open the drain cock with the switching cock still circulating to drain the sample from the sample reservoir.

At this time, if the drain cock is left open for too long, the plasma cannot be maintained, so the drain cock must be closed at the same time as the discharge is completed.

Next, introduce a new sample by introducing the switching cock,
After the introduction is complete, the switching cock is turned on to circulate. [Problem to be solved by the invention] In the conventional sequence mentioned above, the sample that is on the inner wall of the spray chamber and the flow from the sample reservoir to the switching cock are The sample in the tube, the sample in the tube from the sample container to the switching cock, the sample in the tube from the switching cock to the nebulizer, and the sample in the nebulizer remain when replacing the sample. .

Therefore, these samples that have already been analyzed will be replaced with new samples by diluting them little by little, so the replacement will not be completed in the -degree sequence, and the previous sequence will have to be repeated several times. However, there was a problem in that a large number of samples and time were required to replace the sample.

Here, although the sample introduction method is a circulation type for the purpose of performing analysis with a small amount of sample, the fact that a large amount of sample is required is a serious drawback of the conventional method.

The present invention has been made to solve such problems, and an object of the present invention is to provide a sequence in which a new sample is introduced after co-washing the sample in the apparatus.

[Means for Solving the Problems 1] The above object according to the present invention is achieved by the sequence shown in FIG.

Replacement of the analysis sample and analysis are performed according to the following sequence.

In other words, after a certain analysis is completed, first, for an appropriate amount of time,
Open the drain cock while leaving the switching cock in circulation mode.

Next, close the drain cock, switch the switch cock to introduction, and introduce a new sample.

Next, leave the switch cock in the inlet position and open the drain cock.

Next, close the drain cock, introduce a new sample with the cut cock still in the introduction position, and then set the cut cock to circulation.

A sample introduction method for a high-frequency inductively coupled plasma emission spectrometer, characterized in that the analysis sample is exchanged and analyzed according to a sequence in which analysis is started after a time required for the signal to stabilize.

[Effect] The sequence of the present invention has the following function.

After a certain analysis is completed, opening the drain cock while leaving the switch cock in circulation mode is to drain the sample in the sample reservoir to the outside of the spray chamber, and drain the sample in the tube from the sample reservoir to the switch cock. This is because it is discharged into the spray chamber.

Next, close the drain cock because plasma cannot be maintained if the drain cock is left open for a long time.

Next, a new sample is introduced by switching the switching cock: the sample in the tube from the sample container to the switching cock, the sample in the tube from the switching cock to the nebulizer, and the sample in the nebulizer. This is to replace the sample adhering to the inner wall of the spray chamber with a new sample.

Furthermore, the reason for opening the drain cock with the switch cock still in place is to drain the sample from the sample reservoir without guiding it into the tube from the sample reservoir to the switch cock (at this point, The sample reservoir contains a new sample diluted with the sample already analyzed).

As described above, the samples on the inner wall of the spray chamber, the sample reservoir, and each tube are almost replaced with new samples.

Finally, the reason for keeping the switch cock in place is to introduce the amount of new sample needed for the next analysis.

The reason for starting the analysis after waiting for a while after the introduction of a new sample is to wait for the signal to stabilize.

By using the above sequence, when introducing a new sample, the amount of the sample that has already been analyzed remaining in the sample introduction device can be reduced to an almost negligible level.
Substitutability is improved, and by using the sequence of the present invention, substitution can be completed by repeating the sequence - times,
The time and sample required for replacement can be significantly reduced.

Also, if the time required for each operation is determined in advance,
Sample introduction can be achieved with a single switch using a timer, microprocessor, etc.

Additionally, the process from sample introduction to the start and end of analysis can be automated.

[Example 1 Hereinafter, the present invention will be explained in detail based on the drawings.

Figure 1 is an example of the sequence of the present invention, Figure 2 is a block diagram of the sample introduction device used in the present invention, and Figure 3 is an explanatory diagram showing the state of the sample in each part of the introduction device considered in the present invention. It is. The sequence will be explained below.

Here, the explanation starts from the point at which a certain analysis is completed. At this time, the switching cock is in circulation mode and the drain cock is closed.

First, drain the VD of the sample reservoir to the outside, and
In order to discharge the sample T3 in the tube from to the switching cock 5 and the sample T2 in the nebulizer 2 from the switching cock 5 into the spray chamber, the drain cock 1e is
Open for seconds.

Next, switch the switch cock 5 to the introduction mode, and continue for 2 minutes.
Introduce a new sample 6 and press the switching cock 5 from the sample container.
The sample Tl in the tube from the switching cock 5 to the nebulizer and the sample T2 attached to the inner wall of the nebulizer 2 and the sample Vc attached to the inner wall of the spray chamber l are replaced with new samples.

After that, open the drain cock e for 10 seconds and
Eject a new sample mixed with 2 and Vc.

Next, the switching cock 5 is kept switched to introduction, and a new sample to be analyzed next is introduced for 1 minute, and then switched to circulation.

Finally, wait 1 minute until the plasma stabilizes and start the analysis.

In the above example, 14 cc for 1 analysis and 0 for sample replacement.
．． Using a 7 cc sample, a total of 2.1 cc of sample could be analyzed for 30 minutes.

This is the amount of genus % of the conventional sample.

FIG. 4 shows how samples are replaced by the conventional sequence and the sequence of the present invention. After introducing a blank sample, when introducing a standard solution of Cdlppm, and when Cdlppm standard solution was introduced,
This is the state of sample replacement when a blank sample is introduced after introducing an lppm standard solution. According to the present invention, in both cases, the replacement is completed in almost one replacement,
It can be seen that the substitutability was improved.

[Effects of the Invention] According to the present invention, the substitution can be completed by repeating the sequence once, and the time required for the substitution can be significantly shortened, and analysis can be performed over a long period of time with an extremely small amount of sample.

[Brief explanation of drawings]

Figure 1 is an example of the sequence of the present invention, Figure 2 is an example of the apparatus used in the present invention, Figure 3 is an explanatory diagram when considering sample replacement in the example of the present invention, and Figure 4 is an explanatory diagram when considering sample replacement in the example of the present invention. The figure shows the substitutability between the embodiment of the present invention and the conventional embodiment, and FIG. 5 shows an embodiment of the conventional sequence. ■ ・ ・ la ・ lb ・ 1 c ・ d le ・ 2 ・ ・ 3 ・ ・ a ・・Spray chamber・・Connection section・・Nebulizer connection section・・Discharge port・・Sample reservoir・Drain cock・Nebulizer・・Torch tube・Sample introduction part, nebulizer connection member, switching cock and above

Claims (8)

[Claims] (1) A nebulizer that atomizes the sample, a spray chamber that sorts the particle size of the sample mist, a torch tube that introduces the sample mist sorted in the spray chamber into the plasma, and is installed at the bottom of the spray chamber. A drain cock is provided at the bottom of the sample reservoir and is formed to allow the sample to be stored and discharged. In a sample introduction device for a high-frequency inductively coupled plasma emission spectrometer, which is configured with a switching cock configured to allow the sample to be transferred or The drain cock is closed, and after a certain analysis is completed, the sample in the sample reservoir is discharged to the outside of the sample reservoir, and the sample in the tube from the sample reservoir to the switching cock is sprayed. Open the drain cock for the appropriate amount of time necessary to drain into the room, close the drain cock, and drain the sample in the tube from the sample container to the switching cock and the sample in the tubing from the switching cock to the nebulizer. , press the switch cock to transfer the new sample to the nebulizer for an appropriate amount of time necessary for the sample in the nebulizer and the sample adhering to the inner wall of the spray chamber to be replaced with the new sample to be analyzed next. Introduce a new sample into the nebulizer by switching to Introduce new sample into the nebulizer, hold the switch cock to introduce new sample into the nebulizer, and turn off the drain cock for the appropriate amount of time necessary to drain the sample from the sample reservoir. Open the drain cock, close the drain cock, and then open the new sample by holding the switch cock to introduce the new sample into the nebulizer for the appropriate amount of time necessary to introduce the required amount of sample to perform the analysis. The exchange and analysis of the analytical sample are performed according to the following sequence: the switching cock is switched to introduce the sample from the sample reservoir into the nebulizer, and after the time required for the signal to stabilize, the analysis is started. Characteristic sample introduction method for high-frequency inductively coupled plasma emission spectrometer. (2) The above-mentioned "appropriate time required to discharge the sample in the sample reservoir to the outside of the sample reservoir and discharge the sample in the tube from the sample reservoir to the switching cock into the spray chamber" is,
The sample introduction method for a high frequency inductively coupled plasma emission spectrometer according to claim 1, wherein the time is 3 seconds to 15 seconds. (3) The sample in the tube from the sample container to the switching cock, the sample in the tube from the switching cock to the nebulizer, and the sample in the nebulizer,
3. Appropriate time required for the sample adhering to the inner wall of the spray chamber to be replaced with a new sample to be analyzed next.
The method of introducing a sample for a high frequency inductively coupled plasma optical emission spectrometer according to claim 1, wherein the time is from 0 seconds to 5 minutes. (4) The high-frequency inductive coupling according to claim (1), wherein the "appropriate time for introducing the amount of sample necessary for the next analysis" is from 30 seconds to 5 minutes. Sample introduction method for plasma emission spectrometer. (5) The “time required for the signal to stabilize” is 3
The method of introducing a sample for a high frequency inductively coupled plasma optical emission spectrometer according to claim 1, wherein the time is from 0 seconds to 5 minutes. (6) The sample introduction method for a high frequency inductively coupled plasma optical emission spectrometer according to claim (1), wherein the sequence is operated by one or more timers. (7) Claim (7) characterized in that the sequence is operated by one or more microprocessors.
1) The method for introducing a sample into a high frequency inductively coupled plasma optical emission spectrometer as described above. (8) The sample introduction method for a high-frequency inductively coupled plasma emission spectrometer according to claim (1), wherein the sequence is operated by one or more personal computers.