Abstract

On-line coupling of capillary GC with ICP-MS using the recently commercialized high-temperature interface was developed for the investigation of speciation of arsenic in gas condensates. Arsenic was present as a number of species, the two most abundant species being identified by retention time matching with standards such as triphenylarsine (Ph₃As) and triethylarsine (Et₃As). The calibration graph, obtained for Ph₃As, was linear up to 100 ng mL⁻¹ and the detection limit was 0.05 pg (as As). The arsenic speciation was found to undergo a slight evolution as a function of sample storage time. Spiking with standards was found to change the equilibrium in the system.