JP3047083B2 - Spray chamber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spray chamber and, more particularly, to a spray chamber which is mounted on a high frequency inductively coupled plasma mass spectrometer to atomize a sample, remove liquid droplets, and supply the atomized sample to the element analyzer. -Regarding the chamber.

[0002]

2. Description of the Related Art A high frequency inductively coupled plasma mass spectrometer generally has a structure as shown in FIG. That is, in FIG. 2, the outer chamber 1b and the outermost chamber 1c of the plasma torch 1 are shown.
Is supplied with an argon gas from an argon gas supply source 3 via a gas controller 2, and a sample in a sample tank 5 is atomized in a spray chamber 4 to remove droplets in an inner chamber 1a. It is carried in by argon gas.

On the other hand, a high-frequency current flows through a high-frequency induction coil 6 wound around the plasma torch 1 by a plasma power supply 10, and a high-frequency magnetic field (not shown) is formed around the coil 6. In this state, when electrons or ions are implanted in the argon gas in the vicinity of the high-frequency magnetic field,
By the action of the high-frequency magnetic field, a high-frequency inductively coupled plasma 7 is instantaneously generated. Further, the inside of the fore-chamber main body 11 sandwiched between the nozzle 8 and the skimmer 9 is, for example, 1 Torr. It has been sucked.

Further, ion lenses 14a and 14b are provided in the center chamber 13, and the inside of the center chamber is controlled by a first oil diffusion pump 15 to, for example, 10 ^-4 Torr. The inside of a rear chamber 17 containing a mass filter (for example, a quadrupole mass filter) 16 is
^-6 Torr. It has been sucked.

In this state, the sample vaporized as described above is introduced into the high-frequency inductively coupled plasma 7 to perform ionization and light emission. The ions in the plasma 7 pass through the nozzle 8, the skimmer 9, and the extraction electrode, and are then focused between the ion lenses 14 a and 14 b, and then pass through the mass filter 16 and the secondary electron multiplier 19. Is detected and guided. The detection signal is sent to the signal processing unit 20 and is calculated and processed, whereby an analysis value of the element to be measured in the sample is obtained.

[0006]

On the other hand, FIG.
FIG. 2 is an enlarged cross-sectional view of the chamber, in which 21 is a nebulizer for introducing Ar gas and a sample solution to atomize the sample solution, 22 is a spray chamber main body, 23 is a table, 24 is a cooling block, and 25a to 25b. Reference numeral 25c denotes a Peltier element for cooling the spray chamber main body 22 to maintain a constant temperature, 26 denotes a drain outlet, 27 denotes a partition plate, and 28 denotes an outlet. According to the conventional spray chamber having such a configuration, the water vapor in the spray chamber is discharged from the drain outlet 26.
However, there is a drawback that water droplets of the aerosol sample are drawn out from the outlet 28 and reach the inner chamber 1a in FIG.

In addition, a heater and a Liebig cooling condenser are provided in the middle of the pipe from the nebulizer to the inner chamber 1a in FIG. 2, and the aerosol sample atomized by the nebulizer is heated by the heater. A spray chamber was also used in which the water contained was completely removed by heating at, and then cooled through a Liebig condenser. According to the spray chamber having such a configuration, the moisture contained in the aerosol sample atomized by the nebulizer is completely removed, thereby improving the detection sensitivity and stability. There were drawbacks.

The present invention has been made in view of such circumstances and the like, and has as its object the use of a low-boiling organic solvent such as methanol and the removal of a trace amount of water vapor to reduce the detection limit of iron and the like. It is to provide a spray chamber suitable for improvement.

[0009]

According to the present invention, there is provided a spray chamber having a nebulizer which is atomized when a sample is introduced, a partition plate provided in a spray chamber body, and a cooling water inside. Is supplied, a first Peltier element disposed between the first cooling block and the lower side of the spray chamber body, and an aerosol sample flowing inside the spray chamber body. A second cooling block that is guided and flows through the inside, and a second Peltier element disposed between the second cooling block and the upper side of the spray chamber body, wherein the second cooling block is formed by the second Peltier element. The above-mentioned problem is solved by cooling to a lower temperature than the spray chamber body.

[0010]

The present invention operates as follows. That is, the spray chamber body is cooled by the first cooling block and the first Peltier element, the second cooling block is cooled by the second Peltier element, and the second cooling block is cooled to a lower temperature than the spray chamber body. ing. In this state,
After the sample solution introduced into the nebulizer is atomized into an aerosol sample, the sample solution flows through the inside of the partition plate provided in the spray chamber body so as to be turned back on the inner wall of the spray chamber body. Here, the water vapor of the aerosol sample is cooled on the outer wall surface of the spray chamber body and discharged from the drain outlet. For example, only the aerosol sample having a reduced water content to a vapor pressure of 0 ° C.
The water is guided into the cooling block, and the water content is reduced to a vapor pressure of, for example, -15 ° C.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view showing the structure of an embodiment of the present invention.
The same symbols as those in FIG. 3 are used with the same meanings, and redundant description is omitted here. 30 is a second cooling block, 2
9 is a Peltier element composed of elements 29a to 29c, and 31 is an outlet provided in the second cooling block 28.

In the embodiment of the present invention having such a configuration, the first cooling block 24 and the first Peltier device 25
Thereby, the inner wall surface of the spray chamber main body 22 is cooled to, for example, 0 ° C. Also, the second Peltier element 29
Thereby, the inside of the second cooling block 30 is cooled to, for example, −15 ° C.

In this state, the sample solution introduced into the nebulizer 21 is atomized into an aerosol sample, and then passes through the inside of the partition plate 27 provided in the spray chamber main body 22 to form the spray chamber main body. The fluid flows so as to be folded back by hitting the inner wall 22 (the portion opposite to the portion where the nebulizer 21 is mounted). Here, the water vapor of the aerosol sample is cooled by the outer wall tube of the spray chamber main body 22 and discharged from the drain outlet 25. For example, only the aerosol sample whose water content has been reduced to a vapor pressure of 0 ° C. in FIG. Is guided into the second cooling block 30 as shown by the arrow.

The aerosol sample guided into the second cooling block 30 in this manner is cooled to, for example, −15 ° C. by the second Peltier element 29, and thus, for example, −15 ° C. The water content decreases to the vapor pressure of C. Thereafter, only the aerosol sample having a reduced water content to a vapor pressure of, for example, −15 ° C. is led from the outlet 31 to the inner chamber 1 a in FIG. The present invention can be variously modified without being limited to the above-described embodiment. The operation of the elemental analyzer equipped with the embodiment of the present invention is the same as that of the conventional example described with reference to FIG.

[0015]

According to the present invention as described in detail above, the inside of the second cooling block can be kept at a lower temperature than the inside of the spray chamber main body. There is an advantage that a low-boiling organic solvent such as methanol, which has been difficult to use because of its stability, can be used.

In addition, it is extremely important to remove water vapor from the aerosol sample during laser abrasion, heat vaporization, etc. According to the present invention, a trace amount of water vapor is removed to detect iron and the like. Can be easily improved. Therefore, according to the present invention, a spray which is suitable for use of a low-boiling organic solvent such as methanol, and which is suitable for removing a small amount of water vapor and improving the detection limit of iron and the like.
The chamber is realized.

[Brief description of the drawings]

FIG. 1 is a configuration sectional view of an embodiment of the present invention.

FIG. 2 is a diagram illustrating a general configuration of a high-frequency inductively coupled plasma mass spectrometer.

FIG. 3 is a configuration sectional view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plasma torch 2 Gas controller 3 Argon gas supply source 4 Spray chamber 6 High frequency induction coil 7 High frequency inductive coupling plasma 8 Nozzle 9 Skimmer 16 Mass filter 17 Rear chamber 20 Signal processing unit 21 Nebulizer 22 Spray Chamber body 24 Cooling block 25a to 25c Peltier element 25 Drain outlet 27 Outlet

Claims (1)

(57) [Claims] 1. A spray chamber which is mounted on an elemental analyzer using high frequency inductively coupled plasma to atomize a sample, removes droplets and supplies the sample to the elementary analyzer. A nebulizer, a partition plate provided in the spray chamber body, a first cooling block into which cooling water is supplied, a first cooling block and a lower side of the spray chamber body. The first placed between
A Peltier element, a second cooling block into which the aerosol sample flowing through the inside of the spray chamber body flows and flows in the internal flow path, and the second cooling block and the spray
A second Peltier element disposed between the chamber and the upper side of the main body, wherein the second cooling block is cooled to a lower temperature than the spray chamber main body by the second Peltier element. Spray chamber.