A flame ionization detector for gas chromatography

✍ Scribed by A.E. Thompson

• Publisher: Elsevier Science
• Year: 1959
• Tongue: English
• Weight: 685 KB
• Volume: 2
• Category: Article
• ISSN: 1873-3778
• DOI: 10.1016/s0021-9673(01)86275-0

✦ Synopsis

This paper describes a modiiied form of the single jet flame ionization detector of MCWILLIAM ANI) DEW~\II~. The difference between the modified and the original form of the apparatus lies mainly in the electrical circuit of the amplilier. With the ampli-' fying circuits described below the modified form of the detector has cshibited good base line stability and high sensitivity.

The realizable sensitivity of a detector for gas cllroma.tograplly depends upon the acceptable signal to noise ratio as presented on the recorder chart, therefore the base line drift and noise level of detecting and measuring apparatus should be as low as possible. It is convenient to consider separately the two main parts of a flame ionization detector, the combustion chamber (detector) and electronic amplifier, A reliable detector is simple to design and construct but a suitable amplifier is more of a problem, as it requires to have a very high input resistance, low output resistance, low noise level, and a. high degree of linearity between input and output if peal; areas are to be measured.

The amplifiers to be described have all these features, several llavc been constructed, the measured noise level of one 'i's stated, and a gas chromatogram using this with a flame detector is shown.