Separation of Arsenic and Lead by Electrolysis for Total Reflection X-Ray Fluorescence Analysis

Abstract

In total reflection X-ray fluorescence (TXRF) analysis of trace amounts of arsenic in the presence of lead in environmental water, spectrum interference between the As Kα line (10.54 keV) and Pb Lα line (10.55 keV) is an important issue. In this note, a method was reported for the separation of these elements by electrolysis. Lead was not detected from the electrolyzed solution after the electrolysis of a solution containing 0.1 mg/L of lead. When a solution containing 0.1 mg/L of arsenic (III) and 0.1 mg/L of lead and a solution containing 0.1 mg/L of arsenic (V) and 0.1 mg/L of lead were electrolyzed, lead species were more easily removed than the arsenic species from the solutions, and almost all of the arsenic species remained in the electrolyzed solutions. The utility of electrolysis for decreasing the concentration of lead in solution samples makes it feasible as a method for accurate determination of arsenic concentration by TXRF analysis.