JPH11153543A - Icp analyzer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lessen power consumed by an electric heater to be used as a heat source on the occasion of performing constant temperature control of an ICP analyzer. SOLUTION: This analyzer is provided with a light emitting unit 4 which excites a sample by a high-frequency plasma flame 6 and emits light, a high-frequency power device 1 which supplies high-frequency power to this light emitting unit 4, and a spectroscope 10. A heat exchanger 9 is provided, and the heat of plasma of the light emitting unit 4 and the heat of the high-frequency power device 1 are transmitted to the spectroscope 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to the qualitative analysis of sample elements.
The present invention relates to an ICP (high frequency inductively coupled plasma) emission spectrometer for performing quantitative measurement and the like and an ICP mass spectrometer.

[0002]

2. Description of the Related Art An example of a conventional ICP emission spectrometer is shown in FIG. In the ICP emission spectrometer, the sample is converted into a solution in the light emitting section 4 and introduced into the high-frequency plasma flame 6 to cause excitation light emission. The emission spectrum is separated by the spectroscope 10,
The elements in the sample are qualitatively and quantitatively measured. This plasma is generated by supplying a high frequency to an argon gas by an inductive coupling method and discharging the same. For this purpose, the high frequency power supplied to the high frequency induction coil 5 is generally 0.8 to 2..
5KW, excitation temperature of generated plasma is 6000-7
It is a high-temperature plasma that reaches 000K. Conventionally, the heat generated by the plasma flame 6 has been exhausted to the outside by the cooling device 21 which is forcibly exhausted by a powerful air cooling fan.

Further, in the high-frequency power supply device 1 for generating a high frequency to be supplied to the high-frequency induction coil 5,
Heat of diodes and transistors used in the power supply,
In addition, there is heat generated from a dummy load resistor that processes a large amount of power in the RF unit. For cooling such heat, conventionally, forced air cooling by a fan or a DC power supply heat exchanger 2 and R
A water-cooling jacket was installed as the F-section heat exchanger 3, and the heat was discharged to the outside of the apparatus by a method such as using a cooling device 22.

On the other hand, a spectroscope 10 for dispersing the emission spectrum emits the sample excitation light by the plasma flame 6 into the entrance slit 1.
3, when the spectroscope 10 is a polychromator, the light is dispersed for each wavelength by the diffraction grating 11, and the spectrum image is formed on a plurality of exit slits 12 provided for each wavelength. The spectral intensity is measured photometrically by the detector. When the spectroscope 10 is a monochromator, the diffraction grating 11 rotates and scans each wavelength sequentially to one exit slit to perform photoelectric photometry. In any spectrometer, the spectrum must be correctly and sharply imaged on the exit slit 12, and whether or not the sharpness is satisfied is directly related to the most important performance of the spectrometer, that is, the resolution. If it is not at the correct position, a wavelength error will occur.

[0005] The spectroscope used for ICP emission analysis has a resolution of 500,000 to 100,000 and a reverse linear dispersion of 2 to 2.
Focal length 75-100c to obtain 0.2nm / mm
m large spectrometer is used, and the opening width of the entrance slit and exit slit is measured at 20 to 50 μm. In order to obtain the above-mentioned performance with such a large spectroscope, the relative positions of the optical elements such as the entrance slit, the diffraction grating, and the exit slit of the spectroscope are stable on temperature change and vibration on the order of μm. It is required that there be. For this purpose, it is not sufficient to install the device in a normal constant temperature chamber, and constant temperature air is circulated around the outer periphery of the spectroscope so that there is no fundamental temperature change. The temperature of the circulating air is adjusted by the temperature adjusting device 14. An electric heater 15 is installed and the temperature is detected by the temperature sensor 16 so that the cost problem and the temperature change can be minimized. Is adjusted so that warm air of a constant temperature is always circulated by the fan 17.

A liquid sample is excited by a high-frequency inductively coupled plasma similar to that of an ICP emission spectrometer, and qualitative and quantitative measurement of the sample element is performed by mass spectrometry utilizing the ionization of the sample element. There is an ICP mass spectrometer. FIG. 4 shows an example of a conventional ICP mass spectrometer. The ionization unit 4I for ionizing a sample and the high-frequency power supply 1 are exactly the same as the ICP emission spectrometer.
The description is omitted because it is exactly the same as the P emission spectrometer. A quadrupole mass analyzer 18 is usually used as a mass spectrometer used in the analysis part. This creates a hyperbolic electric field by applying an electric field with DC and high frequency superimposed on four cylinders,
In order to stabilize this high-frequency electric field, the output high-frequency is rectified by a diode to obtain a monitor feedback signal. The temperature dependence of the operating characteristics of the diode is an important issue, and the diode current at a fixed voltage increases almost exponentially with temperature (the voltage at a fixed current decreases almost linearly with temperature). Therefore, it is necessary to operate the diode at a constant temperature, and similarly to the spectroscope of the ICP emission spectrometer, temperature control using the electric heater 15 is performed to keep the inside of the high-frequency oscillation unit 19 for obtaining a high-frequency signal at a constant temperature. ing. The method of this temperature control is the same as that of the spectroscope of the ICP emission spectroscopy analyzer, and the detailed description is omitted.

[0007]

The conventional ICP emission spectrometer and ICP mass spectrometer are constructed as described above. However, in order to control the temperature of the spectroscope 10 and the high-frequency oscillator 19 at a constant temperature, a conventional method is used. The temperature is controlled so as to be a constant value higher than the room temperature of, for example, 38 ° C. in the former case and 42 ° C. in the latter case. For this reason, an electric heater 15 of about 200 W is installed, and a relatively large heater power is required. There was a problem to do.

[0008] The present invention has been made in view of such circumstances, and an electric heater 15 used for temperature control is provided.
It is an object of the present invention to provide an ICP analyzer which can be operated with low power.

[0009]

In order to achieve the above object, an ICP analyzer according to the present invention comprises a light emitting section for exciting a sample with a high frequency plasma flame to emit light, and a high frequency power supply for supplying high frequency power to the light emitting section. In an ICP emission spectrometer equipped with a power supply device and a spectroscope for splitting light from the light emitting unit, a heat exchanger for sending the heat of the plasma of the light emitting unit or the heat of the high frequency power supply device to the spectrometer is provided. Things.
Furthermore, an ionization unit that excites and ionizes the sample with a high-frequency plasma flame, a high-frequency power supply that supplies high-frequency power to the ionization unit, and a mass spectrometer that separates and detects ions from the ionization unit are provided. The ICP mass spectrometer is an analyzer provided with a heat exchanger for sending the heat of the plasma of the ionization unit or the heat of the high-frequency power supply to the high-frequency oscillation unit of the mass spectrometer.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the ICP analyzer of the present invention is shown in FIG.
The CP mass spectrometer will be described with reference to FIG.

In FIG. 1, reference numeral 1 denotes a high-frequency power supply for supplying high-frequency power to a high-frequency induction coil 5. The DC power supply unit heat exchanger 2 and the RF unit heat exchanger 3 are installed in the DC power supply unit and the RF unit serving as internal heat generation sources, respectively. Reference numeral 4 denotes a light emitting unit for performing sample excitation emission by plasma. A light emitting unit 4 includes a plasma flame 6 for exciting a sample, a high-frequency induction coil 5 for generating plasma, and a heat exchanger 7 above the plasma flame 6. Reference numeral 10 denotes a spectroscope for measuring the spectral intensity by dispersing the emission spectrum of the sample.
3. There is a diffraction grating 11, an exit slit 12, and an electric heater 15, a temperature sensor 16, and a fan 17 outside the spectroscope 10, which are controlled by a temperature controller 14. Further, the heat exchanger 9 is placed near the electric heater 15. The heat exchangers 2, 3, 7, and 9 form one closed loop with a pipe 20. The pipe 20 is filled with water as a heat medium, and a pump 8 is connected on the way.

Next, the constant temperature control operation of FIG. 1 will be described.
DC power source and R which are heat sources in the high-frequency power supply 1
The heat generated from the F section is absorbed by the DC power supply section heat exchanger 2 and the RF heat exchanger 3, and further, the heat of the plasma flame 6 is absorbed by the heat exchanger 7 in the light emitting section 4, and the temperature of the pipe 20 becomes high. The reflux water in the inside is changed by the pressure of the pump 8 into the spectroscope 10.
The heat is radiated in the heat exchanger 9 installed on the outer periphery of the heat exchanger. This heat is dissipated not only by the heat of the electric heater 15 as in the conventional method but also by the heat exchanger 9 because the heat exchanger 9 is installed near the electric heater 15 which is the original heat source of the temperature control device 14. The heat of the electric heater 15 and the heat of the electric heater 15 merge and return to the outer periphery of the spectroscope 10, and the temperature control device 14 adjusts the voltage of the electric heater 15 by the operation of the temperature sensor 16 to
Is kept at a constant temperature.

FIG. 2 shows an example of an ICP mass spectrometer. In FIG. 2, reference numeral 1 denotes a high-frequency power supply for supplying high-frequency power to a high-frequency induction coil 5, and includes a DC power supply heat exchanger 2 and an RF heat exchanger 3 in a DC power supply unit and an RF unit serving as internal heat sources. Is installed. Reference numeral 4I denotes an ionization section for performing sample excitation ionization by plasma, in which a plasma flame 6 for exciting a sample, a high-frequency induction coil 5 for generating plasma, and a heat exchanger 7 above the plasma flame 6 are provided. 1
Reference numeral 8 denotes a quadrupole mass analyzer, which mass-separates these ions in which the elements in the sample are ionized to measure a mass spectrum. A high-frequency oscillator 19 for supplying a high-frequency electric field to the quadrupole mass analyzer 18 There is. Inside, an electric heater 15, a temperature sensor 16, and a fan 17 are installed, and the temperature is controlled by a temperature controller 14. Further, the heat exchanger 9 is placed near the electric heater 15. The heat exchangers 2, 3, 7, and 9 form one closed loop with a pipe 20. The pipe 20 is filled with water as a heat medium, and a pump 8 is connected on the way.

Next, the constant temperature control operation of FIG. 2 will be described.
DC power source and R which are heat sources in the high-frequency power supply 1
The heat generated from the F section is absorbed by the DC power supply section heat exchanger 2 and the RF heat exchanger 3, and the heat of the plasma flame 6 is absorbed by the heat exchanger 7 in the ionization section 4 </ b> I, so that the pipe 20 is heated to a high temperature. The reflux water inside is radiated by the pressure of the pump 8 in the heat exchanger 9 installed in the high-frequency oscillator 19. This heat is released by the heat exchanger 9 from the original temperature control device 1.
4, the heat of the heat exchanger 9 and the heat of the electric heater 15 are combined together with the heat of the electric heater 15 as in the conventional method. The inside of the high-frequency oscillator 19 is refluxed, and the temperature controller 16 adjusts the voltage of the electric heater 15 by the operation of the temperature sensor 16 to maintain the inside of the high-frequency oscillator 19 at a constant temperature.

In the present invention, the reflux of water is used as a medium for heat exchange, but a heat pipe can be used for transferring heat. The heat pipe encloses a medium, which is called a working fluid, which is easily changed into a gas phase and a liquid phase, in a closed pipe, and has one end placed in the heat exchangers 2, 3 and 7, which are heat source sections, and the other end placed in a heat radiating section. The medium that evaporates in the heat source section and becomes a vapor stream by being placed in a certain heat exchanger 9 is condensed in the heat radiating section and returns to the heat source section as a liquid stream. To repeat the heat exchange action. According to the method using this heat pipe, an excellent heat transfer effect can be expected,
In addition, there is an advantage that no power such as the pump 8 is required to carry the heat transfer element (since the capillary pressure of a porous substance called a wick is used to reflux the liquid from the condensation section to the evaporation section). .

In the above embodiment, the heat generated from the high-frequency power supply device and the heat generated from the plasma flame are used, but a sufficient effect can be obtained by using only one of them.

[0017]

The ICP analyzer of the present invention is constructed as described above, and does not discard heat generated from the DC power supply or RF part of the high-frequency power supply and heat generated from the plasma flame to the outside. Since the spectroscope and the high-frequency oscillation section are taken into a part of the heat source for controlling the temperature at a constant temperature, the power consumption of the electric heater, which is the heat source for control, can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing one embodiment of an ICP emission spectrometer of the present invention.

FIG. 2 is a diagram showing one embodiment of an ICP mass spectrometer of the present invention.

FIG. 3 is a view showing one embodiment of a conventional ICP emission spectrometer.

FIG. 4 is a diagram showing one embodiment of a conventional ICP mass spectrometer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... High frequency power supply device 2 ... DC power supply part heat exchanger 3 ... RF part heat exchanger 4 ... Light emitting part 4I ... Ionization part 5 ... High frequency induction coil 6 ... Plasma flame 7 ... Heat exchanger 8 ... Pump 9 ... Heat exchanger DESCRIPTION OF SYMBOLS 10 ... Spectroscope 11 ... Diffraction grating 12 ... Emission slit 13 ... Ingress slit 14 ... Temperature control device 15 ... Electric heater 16 ... Temperature sensor 17 ... Fan 18 ... Quadrupole mass analyzer 19 ... High frequency oscillation part 20 ... Piping 21 ... Cooling Device 22 ... Cooling device

Claims (2)

[Claims] 1. An ICP light emitting device comprising: a light emitting unit for exciting a sample with a high frequency plasma flame to emit light; a high frequency power supply device for supplying high frequency power to the light emitting unit; and a spectroscope for dispersing light from the light emitting unit. An ICP emission spectroscopy apparatus, further comprising a heat exchanger for sending the heat of the plasma of the light emitting section or the heat of the high frequency power supply to the spectroscopic section. 2. An ionization section for exciting and ionizing a sample with a high-frequency plasma flame, a high-frequency power supply for supplying high-frequency power to the ionization section, and a mass spectrometer for separating and detecting mass of ions from the ionization section. IC equipped with
In the P mass spectrometer, the heat of the plasma in the ionization section,
Alternatively, an ICP mass spectrometer is provided with a heat exchanger that sends heat of the high frequency power supply to a high frequency oscillator of the mass spectrometer.