TGA/FTIR study of the behavior of sodium and potassium citrates in the decomposition of 3R4F tobacco. N2 and air atmospheres

Abstract

Citrates are common burning aids added to tobacco. In this work, the effect of the cation present in the citrate, sodium and potassium, on its thermal and oxidative decomposition was studied. Citrates decompose in three stages, elimination of water, loss of CO2, and decomposition of the remaining material. Under N2 atmosphere, the first stage occurs at lower temperatures for sodium citrate than for potassium citrate. The second one takes place at lower temperatures for potassium citrate, whereas the last stage occurs at similar temperatures for both citrates. Moreover, under air atmosphere, sodium citrate decomposes at temperatures higher than potassium citrate. When mixed with tobacco both additives present similar behavior in inert atmosphere and produce almost no modification of the behavior of tobacco with no additive. Nevertheless, under air atmosphere, the temperature of the process associated with the combustion of tobacco is noticeably reduced and a new process appears at high temperatures.