JP3131273B2 - Sample liquid atomizer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for atomizing a sample liquid optimally used in a high frequency inductively coupled plasma apparatus (ICP).

[0002]

2. Description of the Related Art In recent years, ICP and mass spectrometer (MS)
-MS combined with a laser and emission spectrometer (AES)
And ICP-AES have been put to practical use.

In the ICP, a sample solution is ionized by using plasma. At this time, as a method of introducing the sample solution into the plasma, the sample solution is atomized by using a nebulizer as shown in FIG. There is a method of jetting into plasma.

In FIG. 1, reference numeral 7 denotes a spray chamber, and a sample atomized by a nebulizer 14 opened in the spray chamber 7 is sent from an outlet 8 to a plasma torch (not shown). Droplets generated by, for example, colliding with the wall surface of the spray chamber are drained from the drain port 13. Outer cylinder 1 of nebulizer 14
Is finely squeezed to form an atomizing gas jet 2 at the tip,
The other end of the outer cylinder 1 is closed by a bottom 3. An inner cylinder 4 is disposed substantially concentrically inside the outer cylinder 1, one end of which is placed close to the jet port 2, and the other end of which is fixed to the bottom 3. The inner cylinder 4 is configured to communicate with a sample supply pipe 5 fixed outside the bottom 3, and arbitrary gas is supplied from the atomizing gas introduction pipe 6 through the gas introduction amount adjustment valve 15 to the outer cylinder. The gas is ejected toward the ejection port 2 through a gap S formed between the inner cylinder 1 and the inner cylinder 4. In general, these members are formed using quartz glass having excellent heat resistance.

In such a configuration, a gas introduction amount adjusting valve 15 and an atomizing gas introduction pipe 6 are connected to a gas cylinder (not shown).
When the argon gas introduced through the nozzle is ejected from the ejection port 2 through the gap S of the outer cylinder 1 and the sample liquid is introduced into the inner cylinder 4 from the sample supply pipe 5, the sample liquid is ejected from the ejection port 2.
After being atomized by the argon gas ejected from the nozzle, it is taken out from the outlet 8 and fed into a plasma torch (not shown) to be ionized.

[0006]

In such an apparatus, for example, when the viscosity of the sample liquid introduced into the sample supply pipe 5 of the nebulizer changes, the gas introduction amount is adjusted so as to maintain the optimal atomization state. The valve 15 adjusts the flow rate of the atomizing gas. By adjusting the flow rate of the atomizing gas, the flow rate of the gas introduced into the plasma torch (not shown) changes, and the change in the flow rate changes the temperature of the gas in the plasma. As a result, the measurement sensitivity changes and the reproducibility of the data decreases.

Therefore, the present invention has been made in view of such a problem, and maintains an optimum atomization state while
It is an object of the present invention to provide a sample liquid atomizing device capable of preventing a change in measurement sensitivity.

[0008]

Means for Solving the Problems In order to achieve the above object, the present invention provides a nebulizer for atomizing a sample liquid by a gas ejected from an atomizing gas ejection port, and a spray chamber for accommodating the nebulizer. In a sample liquid atomizer for removing an atomized sample from an outlet provided in the spray chamber, an atomized sample transporting gas for sending the atomized sample toward the outlet is sprayed. An outlet for supplying to the chamber is provided near the atomizing gas outlet of the nebulizer.

[0009]

According to the present invention, an injection port is provided near an atomizing gas injection port of a nebulizer, and an atomized sample transport gas for sending an atomized sample from the injection port toward the output port is supplied to a spray chamber. I am trying to introduce it.

[0010]

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

In FIG. 2, the same components as those in FIG. 1 are denoted by the same reference numerals. In the figure, reference numeral 12 denotes an outermost cylinder provided substantially concentrically on the outer periphery of the outer cylinder 1, one end of which is narrowed narrowly and the ejection port 10 is formed at the tip. In addition, the outermost cylinder 12
Is attached to the outer periphery of the outer cylinder 1 by fusion or the like, and an arbitrary gas sent from the gas introduction pipe 9 passes through a gap S ′ formed between the outer cylinder 1 and the outermost cylinder 12. It is spouted from spout 10.

In this configuration, as described above, when the viscosity of the sample liquid becomes high, the measurer operates the first gas introduction amount adjusting valve of the atomization gas introduction pipe 6 so as to obtain an optimal atomization state. By turning 15 in the opening direction, the amount of gas introduced from a gas cylinder (not shown) is increased. Further, the measurer turns the second gas introduction amount adjusting valve 16 of the gas introduction pipe 9 in the closing direction to reduce the amount of gas introduced from a gas cylinder (not shown), thereby reducing the gas introduction amount from the ejection port 10 and the ejection port 2. The total flow rate of the ejected gas is adjusted to be constant.
That is, the amount of gas introduced from the gas introduction pipe 9 for transporting the atomized sample is reduced by the amount of gas introduced by the introduction pipe 6, so that a certain amount of gas is directed toward the outlet 8 of the spray chamber 7. Sent. Conversely, when the viscosity of the sample liquid decreases, the first gas introduction amount adjusting valve 15 is turned in the closing direction,
Since the amount of introduction of the atomizing gas is reduced to achieve the optimal atomization state, in this case, the second gas introduction amount adjusting valve 16 is turned in the opening direction to keep the total gas flow rate constant. It is adjusted to become.

As a result, even when the liquid property of the sample liquid changes, the optimum atomization state can be maintained and the total flow rate of the gas taken out from the outlet of the spray chamber can be kept constant. The flow rate of the gas introduced is also constant. As a result, a temperature change of the gas in the plasma torch can be prevented, so that ionization,
A change in measurement sensitivity can be prevented without changing the degree of excitation. Further, by providing the gas ejection port for atomizing sample transport coaxially around the gas ejection port for atomization as in the above embodiment, the gas for atomizing sample transport is ejected so as to enclose the atomized sample. Therefore, the collision of the atomized sample with the inner wall of the spray chamber is reduced, and the loss of the atomized sample caused by the collision can be reduced.

In the above embodiment, the outer cylinder 1 of the nebulizer is used.
Although the outermost cylinder is provided substantially concentrically around the outer periphery for supplying the gas for transporting the atomized sample, the invention is not limited to this. The gas introduction pipe may be arranged at another position.

In the above embodiment, the gas introduction amount of the gas introduction pipes 6 and 9 is controlled by the first and second gas introduction amount adjusting valves 1.
It is assumed that the gas is adjusted separately in steps 5 and 16 and supplied to the nebulizer. However, the invention is not limited to this. You may make it do.

Further, in the above embodiment, the argon gas is introduced from the gas introduction pipe 9. However, the invention is not limited to this. If another gas having high thermal conductivity is introduced from the gas introduction pipe 9, the sample in the plasma may be introduced. Can be increased, and ionization is further promoted. In addition, gas introduction pipe 9
A gas that causes a chemical reaction with the sample may be introduced and reacted in the spray chamber, and the product may be ionized in the plasma torch, or the temperature of the gas introduced from the gas introduction pipe 9 may be varied. It may be.

In the above embodiment, a coaxial nebulizer has been described. However, the present invention is not limited to this, and a cross-flow nebulizer may be used.

[0018]

As described in detail above, the present invention provides a nebulizer with an atomized sample transporting gas outlet near the atomizing gas outlet to keep the total flow rate of gas sent to the outlet constant. can do. This makes it possible to maintain an optimal atomization state and prevent fluctuations in measurement sensitivity.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a conventional example.

FIG. 2 is an enlarged view of a main part of an apparatus according to an embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 9 gas introduction pipe for atomized sample transport 10 gas injection port for atomized sample transport 11 bottom 12 outermost cylinder 16 second gas introduction amount adjustment valve S 'gap

Claims (1)

(57) [Claims] 1. A nebulizer for atomizing a sample liquid by a gas ejected from an atomizing gas ejection port, and a spray chamber for accommodating the nebulizer, wherein a nebulizer is atomized from an outlet provided in the spray chamber. In the sample liquid atomizing apparatus configured to take out the sample, the atomizing gas jet port of the nebulizer is provided with an jet port for supplying an atomized sample transporting gas for sending the atomized sample toward the outlet to the spray chamber. A sample liquid atomizing device, which is provided in the vicinity of