Flow injection thermal analysis mass spectrometry: Application to studies of carbon gasification reactions

Flow injection combined with thermal analysis-mass spectrometry is a useful technique for studying gasification reactions. It provides a rapid, powerful method of separating the variables of a particular reaction, such as reactant concentration, reactant composition and temperature, studying their influence on the reaction products and differential thermal analysis. The present work illustrates the technique using the following examples: (1) the reaction of NO with carbon, and (2) the reaction of NH3 and NO over carbon. In both cases, >99% isotopically pure C-13 was used, so that N-2 and CO, and also N2O and CO2 could be mass-resolved. The results also illustrate the application of the technique to the study of the effect of oxygen concentration and gasification temperature on the formation of N2O and N-2 during the NO-carbon reaction. The results show that the N2O:N-2 ratio increases with oxygen concentration while the N2O concentration decreases with increasing temperature. (C) 1997 Elsevier Science Ltd. All rights reserved.