Slurry atomization using hydrogen-modified inductively coupled plasmas

Abstract

The use of molecular gas addition as a volatilization aid in slurry nebulization inductively coupled plasma atomic emission spectrometry (ICP-AES) has been investigated using a combination of rigorous optimization strategies and spectrochemical measurements. The addition of hydrogen resulted in an improvement in accuracy, which corresponded to the elimination of atomization interferences observed during the analysis of a highly refractory material by slurry nebulization ICP-AES. This ability to decompose refractory particles correlated with higher rotational plasma temperatures. This increase in temperature from 2200 to 3900 K was attributed to increased energy transfer from the toroidal to the annular region of the ICP as a consequence of the higher thermal conductivity of hydrogen compared with argon. This process appears to be self-limiting and a mechanism is proposed to account for this behaviour.