JPS60231142A - Icp quantometer - Google Patents

Abstract

PURPOSE:To attain to reduce the operation cost of an ICP quantometer, by making it possible to supply low purity argon gas when argon supplied to a plasma torch may be low purity. CONSTITUTION:Selection valves C1, C2 are opened and closed by the order from a computer 5 so as to be made contrary to each other. High and low purity argon gas bombs 6, 7 are connected to a gas controller 4 through the selection valves C1, C2. For example, when lighting operation is started, the computer 5 opens the valve C1 at first to supply high purity argon gas to a plasma torch 1 and a high frequency circuit not shown in the drawing is controlled to light plasma. When the plasma is lighted, an optical sensor 8 issues a signal. The computer 5 closes the valve C1 upon the reception of said signal and opens the valve C2 with the closing of the valve C1 to change over argon gas supplied to the plasma torch 1 from high purity to low purity. This operation is performed because the light of high purity argon is easily lighted at the time of the lighting of a plasma flame.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a high frequency inductively coupled plasma (CP) emission spectrometer.

■Conventional technology: A CP emission spectrometer supplies argon gas to a plasma torch, forms a plasma flame through electromagnetic induction due to high frequency waves, and the high temperature of this plasma flame atomizes the sample introduced into the plasma flame, causing it to emit light. It separates that light into spectra.

Conventionally, high-purity argon gas was exclusively supplied to the plasma torch of an ICp emission spectrometer, but since ICp emission spectroscopy consumes a large amount of argon gas, it is difficult to operate the analyzer when using expensive high-purity argon gas. The cost was much higher than that of other types of analyzers.

On the other hand, it is desirable that the argon gas connected to the plasma torch in ICP analysis be of high purity, but in some cases, relatively low purity argon gas is often sufficient, and even in such cases, high purity argon gas is required. The use of gas is economically wasteful.

The present invention aims to reduce the operating costs of the industrial CP emission spectrometer by making it possible to supply low-purity argon gas when the argon supplied to the plasma torch does not need to be of low purity. 2. Configuration The ICp emission spectrometer of the present invention connects a high-purity argon gas container and a non-high-purity argon gas container to a plasma torch through a selective pulp, and freely connects argon gas of high and low purity to the plasma torch. Embodiment 0 The drawings, which have been made available, show essential parts of an embodiment of the present invention. 1 is a plasma torch with a triple-tube structure, in which the carrier gas is supplied to the center tube, and the plasma gas is supplied to the next tube.
The plasma flame is primarily formed by this gas. The outermost tube is supplied with cooling gas. All of these gases are the same argon gas, and their names represent their functions in the plasma torch. The carrier gas is supplied to the sample atomizer 2, which suctions the sample solution in the container 3 through the atomizing action of the rice and atomizes it into the sample atomizer. It is carried by the central pipe of the torch. The flow rates of the three types of gases mentioned above have appropriate values depending on the dimensions of the plasma torch, the high frequency input, and the type of sample, so they are controlled by the gas controller 4 to the appropriate flow rates. The gas controller 4 has flow rate control valves v1. ■2. v3 and its driver M11M2,
M3 and flow sensor 81. S2, 83 and more, the outputs of these flow rate sensors are taken into the control computer 5,
The values are compared with the set values, and the drivers M1-M3 are operated by control signals from the computer 5.

C1 and C2 are selection valves whose opening and closing are mutually contradictory, and whose opening and closing are controlled by commands from the computer 5. 6. '7 is an argon gas cylinder, 6 is height 14
Degree 7 is filled with low purity argon gas. These gas cylinders are connected to the gas controller 4 via selection valves CI and C2.

An example of an operation program for the switching pulps C1 and C2 is as follows. With the plasma torch lighting program,
When the lighting operation is started, the computer 5 first opens the pulp C1, supplies high purity argon gas to the plasma torch 1, and controls a high frequency circuit (not shown) to light the plasma.

When the plasma is turned on, plasma light enters the optical sensor j and a signal is output from the optical sensor 8. When the computer 5 receives this signal, it closes the pulp C1 and opens C2 accordingly, thereby increasing the plasma. The gas supplied to the torch 1 is switched from high purity argon to low purity argon. This is done because it is easier to use high-purity argon when lighting a plasma flame.

The effect of what is referred to as high purity argon gas is 99.9.
995% or higher, and low purity refers to 99.995% or higher, but this does not mean that it has to be this pure; This is because the plasma flame is maintained at purity 9.
It is possible even at around 9.9%. Low-purity argon is about 30% cheaper than high-purity argon, so if high purity is not required, using low-purity argon as much as possible can significantly reduce the operating costs of the ICp analyzer. can.

[Brief explanation of the drawing]

The drawing is a block diagram showing the main parts of an apparatus according to an embodiment of the present invention. 1... Plasma torch, 2... Sample atomizer, 3...
・Sample container, 4... Gas controller, S1-S3・
...Flow rate sensor, 5...Control computer, 6...
High purity argon gas cylinder, 7...Low purity argon gas cylinder, C1, C2...Switching valve, 8...Photo sensor. Agent Patent Attorney Kosuke Karu

Claims (1)

[Claims] Connect a high-purity argon gas container and a non-high-purity argon gas container to a plasma torch through the selected pulp,
A CP emission spectrometer comprising a control device that operates a selected pulp according to a given program and switches the purity of argon gas supplied to a plasma torch.