GC with FI and PDHI detection for trace impurity analysis in bulk gases: a comparative evaluation

Abstract

Some experimental problems challenge the users when using a GC equipped with FID or PDHID detector in the context of trace level impurity analysis in ultra high purity bulk gases. In this study, a comparative evaluation of GC-FID and GC-PDHID is conducted based on both author’s experiment and literature review in terms of two technical aspects i.e., imitation and capability. Findings shows that both GC-FID and GC-PDHID reflect capability aspect through a pretty detection sensitivity and quantification at trace level of the impurity compounds. Regarding detectability range of compounds, the GC-FID has relatively lower than the GC-FID since the FID responds to only hydrocarbon-type impurity compound, while PDHID can detect almost any compound, except neon. In case of limitation aspect for these two instruments, detectable range of target compounds and operating cost are remarkable. In addition, in context of operating cost and maintenance, however, the FID is relatively inexpensive in comparison to that of PDHID. Besides aforementioned technical aspects, other capabilities and limitations of both FID and PDHID are also evaluated and compared.