Determination of Al in Oxalic Acid by Laser Ablation Coupled With Inductively Coupled Plasma Mass Spectrometry

Oxalic acid is an important reagent in industrial production. The content of metal impurities in oxalic acid affects the quality of the product. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is a widely accepted method for direct sampling of solid materials for trace elemental analysis. In this work, a matrix match external calibration was used to quantify Al in oxalic acid by LA-ICPMS. Laser ablation instrument conditions were evaluated in order to achieve the best intensity. Calibration in the range of 50-2000 ng·g⁻¹ was used. By using the optimized parameters, limit of detection was 3.41 ng·g⁻¹. The accuracy evaluated by comparison with results obtained from solution analysis by ICP-MS after sample decomposition by microwave digestion was relatively good. (paper)