Tunable Selectivity of an Alkali Aerosol Flame Ionization Detector Towards Organobromine and Organoiodide Species for Gas Chromatography

Abstract

The performance of a halogen selective aerosol alkali flame ionization detector (AFID) is presented. A constant delivery of desolvated alkali salt aerosol is introduced into the detector in the form of dual hydrogen gas flames. The problems of enhancement-source vaporization and contamination, which occur in fixed alkali salt versions, do not occur with the presented aerosol design. Detection limits range from 321 pgI/sec to 450 pgI/sec and 6.7 ngBr/sec to 15 ngBr/sec. Selectivity ratios were 10³ gI/gC and 10² gBr/gC using an 100 ppm potassium chloride as the alkali salt solution.

Key Words:

• gas chromatography
• selective organobromine detection
• selective organoiodide detection
• alkali flame ionization detector