Why does the direct reading spectrometer need to be equipped with an argon gas purifier?

Direct-reading spectrometer needs to be equipped with argon gas purifier and spectrometer needs a power supply regulator for the same reason, if you can guarantee that the voltage is 220V, you can not use the regulator, you can guarantee that the purity of argon can reach 5 9 and there is no need to equip with argon purifier.

In addition to ensuring the stability of the output argon purity, the argon gas purifier can also purify pure argon to high purity argon, saving production costs for users.

When the direct reading spectrometer excites the spectrum, it needs to be carried out in an argon atmosphere, so the air in the excitation room should be exhausted during the pre-washing process. During the precombustion and integration time, the evaporated metal vapor should be discharged from the instrument through the exit channel to obtain stable spectral line intensity and the most economical argon consumption. Therefore, the argon supply system is required to provide stable argon pressure and flow rate. To reduce the air on the argon pipe and metal vapor on the lens pollution.

The spark table is connected with the metal support and the spectroscopic chamber through an insulating plate, and a condenser is arranged between the spark table and the spectroscopic chamber, which is the boundary between the spectroscopic chamber and the electrode support, thereby not only enhancing the illumination of the incident slit, but also preventing air and argon from leaking into the spectroscopic chamber.

The main function of argon is to drive away the air in the spark chamber when the sample is excited, and reduce the absorption of the air to the spectral lines in the ultraviolet region. The main reason is that oxygen and water vapor in the air have strong absorption bands in the far ultraviolet region, which have a great impact on the analysis results, and are not conducive to the stability of excitation, forming or strengthening the diffusion discharge, and producing white spots when excited.

Argon not only ensures that the excitation lines are not absorbed by oxygen, but also participates in the discharge to some extent. The atomic weight of argon is larger than that of nitrogen, which accounts for 78% of air, so the energy given to the excited sample particles at the time of impact is also large, directly increasing the intensity of the spectral lines.

In addition, the alloying elements in the sample may react chemically with the components in the air at high temperatures to form molecular compounds, which will cause interference to the atomic spectrum we need. Therefore, it is necessary to require the purity of argon to reach more than 99.999%.

The pressure and flow rate of argon also have a certain effect on the quality of the analysis, which determines the impact ability of argon on the discharge surface. This excitation ability must be appropriate and too low to wash away the oxygen generated during the excitation of the specimen and the oxides it forms, which agglomerate on the electrode surface and thereby inhibit the continued excitation of the specimen. The best condition is when the impact power of the argon gas is sufficient to wash away the oxygen and the agglomerate on the electrode, and at the same time does not cause the spark to jump.

Therefore, the argon pressure and flow rate must be appropriate. The stability of argon spark is conditional, which is related to the stability of argon flow and pressure, and is also affected by the purity of argon.

For direct-reading spectrometers, if the purity of argon does not meet the requirements, it can lead to diffusion discharge during spectral excitation, reduce the intensity, cause no erosion on the surface, and present white spots at the excitation, which ultimately leads to inaccurate analytical data, especially for the analysis of non-metallic elements such as When C, P, S, Si and some high alloy castings, aluminum, cast iron, the effect of argon quality on the data is more obvious.

In summary, ordinary canned argon can not meet the analytical requirements of the spectrometer, only higher purity, stable pressure gas source can be achieved, and the appearance of argon gas purifier completely fills this technical requirement.