Small photoionization detector and detection method thereof

Abstract

The invention relates to a small photoionization detector and a detection method thereof. The detector comprises a vacuum ultraviolet lamp and a detection cavity installed on the right side of the vacuum ultraviolet lamp. The detection cavity comprises an insulating supporting cavity with an opening in the left end, and at least one traction electrode ring, an oscillating electrode I, an oscillating electrode II and a collecting electrode plate which are sequentially arranged on the insulating supporting cavity from left to right; the collecting electrode plate is connected with a current amplifier, and the current amplifier is connected with a controller; an opening in the left end of the insulating supporting cavity is an ultraviolet light incident port, and the collecting electrode plate is mounted at the right end of the insulating supporting cavity; and a gas inlet and a gas outlet are formed in the peripheral wall of the insulating support cavity. The defects in the prior art canbe overcome, qualitative judgment of the to-be-detected object is achieved, and the quantitative detection accuracy of the photoionization detection technology is improved.

Description

technical field [0001] The invention relates to the technical field of on-site analysis and detection instruments, in particular to a small photoionization detector and a detection method thereof. Background technique [0002] Existing photoionization detectors can achieve highly sensitive detection of leakage / environmental pollutants (analyte) such as VOCs, but since the photoionization detector will ionize components that are less than the ionization energy of its light source, therefore, Existing photoionization detectors can only detect the total amount of substances whose ionization energy is lower than the photon energy emitted by the light source, and cannot realize the qualitative judgment of the analyte. At the same time, due to the different ionization efficiencies of different components, when the composition ratio of the analyte is different, the concentration represented by the detection value of the same photoionization detector is not the same. Therefore, the...

AI Technical Summary

Problems solved by technology

Therefore, the existing photoionization detectors can neither achieve qualitative analysis of components, but also have certain shortcomings in quantitative aspects.

In addition, there are also attempts to combine photoionization technology with other detection technologies to achieve qualitative and quantitative analysis, but this is mainly limited to laboratory testing with large-scale equipment, and these application methods only use photoionization technology as a complex analysis system. part, unable to take advantage of its features such as miniaturization and rapid on-site application

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