Slurry analysis by multichannel arc/spark emission spectrometry using a monosegmented system: Determination of aluminium in sediments

This work proposes a new approach for sediment analysis in which the sample is introduced as a slurry in an arc/spark emission spectrometer using a monosegmented system. The spectrometer has been modified to employ a 1024 photodiode-array detector capable of collecting intensities in a 18.7 nm wide wavelength window. Sediment slurries were prepared with 8.5–50 mg of the samples, grounded to a particle size less than 38 μm, transferred to a 50 mL volumetric flask in which 1 mL of conc. HNO₃ and 300 μL of 10% m/v La (as La₂O₃; used as internal standard) were added. The slurry (25 μL) was introduced into the monosegmented system and transported by an air stream to a graphite rod in the existing arc/spark source. About 40 samples can be analyzed per hour. Results for reference materials show acceptable accuracy and precision for the proposed method. © 2000 John Wiley & Sons, Inc. Lab Robotics and Automation 12:46–52, 2000