RESUMO
Identification and characterization of solid samples has been relatively difficult due to the limited separation techniques available. Reported here is the development of a multielemental scanning thermal analysis (MESTA) method that provides a simple, rapid, and sensitive alternative for routine examination of solid samples. A MESTA system heats up a sample in an enclosed quartz tube from ambient to 800 degree C at a constant heating rate and under a given atmosphere. The volatile components in the sample are carried to a high-temperature combustion tube where the C, N, and S are oxidized to their respective oxides and detected by the detectors. The result is the simultaneous C, N, and S thermograms of a sample that can be used as chemical signatures for identification and characterization purposes. Sample heating rate, oxygen content of the carrier gas, and the possible interactions among the ingredients of a sample would all affect the outcome of an analysis. These effects need to be understood for a specific application. The general instrumentation, technique, usefulness, and interpretation of the MESTA are presented with examples. The simplicity and cost-effectiveness of the MESTA make it a promising tool for routine chemical analysis of solid substances.