Determination of Chlorine in Plastics via SrCl by Solid-Sampling High-Resolution Continuum Source Graphite Furnace Molecular Absorption Spectrometry

Abstract

Solid sampling high resolution continuum source molecule absorption spectrometry (SS-HR-CS MAS) was applied for the determination of chlorine in plastic using the strontium monochloride (SrCl) molecule. For this purpose, 10 µL of 20 g L⁻¹ strontium (prepared from Sr(NO₃)₂) solution were pipetted with aqueous Cl standards or 0.05 to 4 mg of slivered plastic samples on a platform and introduced into the furnace. Chlorine was determined with the molecular absorption of SrCl at 635.862 nm using 1100 °C and 2200 °C for the pyrolysis and vaporization temperatures, respectively. Aqueous standards were used for calibration. The accuracy of the method was evaluated using a certified polyethylene reference material. The limit of detection and characteristic mass values of the method were 2.5 ng and 0.4 ng, respectively. The chlorine concentrations in various polyethylene beverage containers were determined.

Keywords:

• Plastic
• solid-sampling high-resolution continuum source graphite furnace molecular absorption spectrometry (SS-HR-CS MAS)
• strontium monochloride