Effects of acid anions, major metallic elements, and chlorides on Li detection by DFWM in graphite furnace

Abstract

In trace Li analysis with degenerate four-wave mixing (DFWM) method, acid anions and major metallic elements are dominant interferences in Li-containing samples. To better use DFWM technique to analyze trace Li in actual samples, we study their effects on Li DFWM signal intensity. It is found that K, Cs, and Ni can enhance the Li DFWM signal, SO 2-4 , PO 3-4 , Cl-, and Ca can cause significant suppression, and NO 3-, Mg, Ba, Sr, and Na almost have no effects. Finally, we use H 3 BO 3 to eliminate the depressive effects of chlorides on Li DFWM signal. The result is also of reference in other trace elements analysis with DFWM.