Understanding PID Analyzers In Detail

Understanding PID Analyzers In Detail The full form of PID is photoionization detector.

PID analyzers are gas chromatographs with a photoionization detector which is basically used for multi-gas analysis. Volatile organic compounds are best detected by the photoionization technique.

The sensitivity quotient is very high in this technique and is able to provide both manual and automatic analysis. The molecules of the sample are broken into positively charges ions by high-energy photons which belong to the vacuum ultraviolet range.

Subsequently, an electric current is produced which gives output to the detector.

The amount of current depends upon the concentration of the substance. The PID analyzers were introduced in the application of gas chromatography in 1976.

Salient Features of PID Analyzers The main features of these instruments are that they have low maintenance time and perform at lengths; it has less moving parts and has electronics which have high durability, and there have high reliability and stability factor and have ability to operate under ambient air pressures.

The biggest benefit of the usage of gas chromatography with PID analyzers is that the matrix effect is at its minimum as the analyte goes into the detector without compounds that have the ability to interfere with the results. We have to keep in mind that when we are working in environments or conditions with high humidity or when methane or methane-like compounds are present the signal produced by PID will be quenched. The ion current is drastically reduced as ionization energies are absorbed by water and methane as they absorb photons emitted by the UV lamps. Resultantly energetic photons for ionizing the analyte are reduced. The main thing to remember is that the sample gas is not burned or changed as gas ions recombine to form the original vapor. As an individual organic compound has its own threshold energy of light it is easy to use to sense by PID. Noble gas and a window material with a photon energy source are the main components of the PID lamps which are used to create photo ions.

Argon, Krypton, Helium, and Xenon are mainly used. Lamps with high output, longest life are mainly advisable and give response to a maximum number of compounds.

A device which supports it thoroughly Another very important device used in gas chromatography is the GC Zero Air generator. We have to first understand of the concept of Zero gas and its necessity. As a layman, you can say that is sterilized, clean, pollutant-free, humidity-free air. As there are technically less than 0.05ppm of hydrocarbons in the Zero air. Also, compounds or gases generally present in the normal air like Sulphur dioxide, carbon dioxide, and carbon monoxide are also absent in zero air.

As the hydrocarbons and other impurities are drastically reduced in zero air and thus the detectors are able to give the best results with better baseline stability and background noise levels are also reduced.

You can get zero air also in cylinders but is preferable to get an onsite GC Zero air generator due to points mentioned in subsequent lines. Delivery costs are nil, cylinder rental charges are non-existent. You are sure of purity on zero gas produced onsite and your investment is returned within one year of purchase.

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