MODELING OF THE EVAPORATION BEHAVIOR OF PARTICULATE MATERIAL FOR SLURRY NEBULIZATION INDUCTIVELY-COUPLED PLASMA-ATOMIC EMISSION-SPECTROMETRY

This paper is an electronic publication in Spectrochimica Acta Electro nica (SAE), the electronic section of Spectrochimica Acta, Part B (SAB ). This hardcopy text, comprising the main body and an appendix, is ac companied by a disk with programs, data files and a brief manual. The main body discusses purpose, design principle and usage of the compute r software for modelling the evaporation behaviour of particles in ind uctively coupled plasma atomic emission spectrometry (ICP-AES). Comput er software has been developed in FORTRAN 77 language in order to simu late the evaporation behaviour of particles of refractory materials su ch as encountered in the analysis of advanced ceramic powders by slurr y nebulization inductively coupled argon plasma atomic spectrometry. T he program simulates the evaporation of single particles in the induct ively coupled plasma and also enable it to calculate on the base of a given particle size distribution the evaporation behaviour of all the particles contained in a sample. In a so-called ''intensity concept'', the intensity is calculated as a function of the observation height i n order to determine recovery rates for slurries compared with aqueous solutions. This yields a quick insight whether a calibration with aqu eous solutions can be used for analysis of slurries of a given powder by slurry nebulization ICP-AES and also is a help in determining the o ptimal parameters for analyses of powders by means of slurry nebulizat ion ICP-AES.Applications for the evaporation of Al2O3 and SiC powders document the usefulness of the model for the case of a 1.5 kW argon IC P of which the temperature at 8 mm above the load coil has been determ ined to be 6100 K. The model predicts the maximum particle size for SI C and Al2O3 that can be transported (10-15 mu m) and evaporated for a given efficiency under given experimental conditions. For both Al2O3 a nd SiC, two ceramic powders of different grain size were investigated. The median particle sizes cover the range typical of ceramic powders. Investigations were made for SiC A 10 (median particle size 2.2 mu m) , SiC F1200 (4.3 mu m) and Al2O3 AKP 30 (<1.9 mu m) and Al2O3 Cilas 71 5 (3.0 mu m), respectively, in which particles with diameters of up to 23 mu m still are found. (C) 1997 Elsevier Science B.V. (C) 1997 Else vier Science B.V.