Radiotracer examination of gas-liquid separators used in arsenic speciation by hydride generation — AAS

Abstract

Two types of gas-liquid separators for use in on-line hydride generation AAS have been examined: the “classical” one, in which gas and liquid are separated by gravity and that based on diffusion through a pemeable tube. Results are presented for the determination of arsenic species (arsenite, As(III); arsenate, As(V); monomethylarsonic acid, MMAA; dimethylarsinic acid, DMAA). Yield (of hydride generation and gas-liquid separation) and response time are investigated as functions of the experimental variables. It is concluded that in conjunction with a cold trap, only the “classical” gas-liquid separator is satisfactory.