Determination of phosphorus in raw materials for ceramics: comparison between X-ray fluorescence spectrometry and inductively coupled plasma-atomic emission spectrometry

This paper compares methods for phosphorus determination in refractory sili coaluminous materials based on inductively coupled plasma-atomic emission s pectrometry (ICP-AES) and X-ray fluorescence (XRF) spectrometry. Chemical i nterferences were studied by using several calibration standards and standa rd additions. The Limits of detection obtained by XRF spectrometry (0.03 an d 0.06 mg P2O5 per gram of sample) are clearly advantageous as compared wit h those obtained by ICP-AES (0.2 mg g(-1)). Phosphorus can successfully be determined by XRF spectrometry with either pressed sample pellets or dilute d sample beads. Matrix effects were minimised by using a certified bauxite as a standard, but several less-similar materials could be used, such as si derurgic slag, chamotte and even dolomite for low P2O5 content samples. The linear calibration range is larger (up to 100 mg g(-1)) when analysis is c arried out by ICP-AES, using the 213.628 nm line. Repeatability is similar with both methods, but XRF spectrometry is preferred on the grounds of the better sensitivity achieved, and the simpler sample preparation requirement s. (C) 2001 Elsevier Science B.V. All rights reserved.