## 1 Introduction
[25] found that the CAS-1 calsilicate removes among 30-60% of TSNAs from the smoke, whereas materials such as NaA zeolite being very effective in removing nitrosamines from air streams, hardly reduced 11% of TSNAs from tobacco smoke. They explained such results being because the fiber morphology of the calsilicate favors the collision of the particulate matter. [PERSON] et al. [26] highlighted the ability of SBA-15 and NaY zeolite for removing the particulate matter and TSNAs, observing a certain selectivity of the SBA-15 due, again, to its fiber-like morphology. These authors also used other zeolitic catalysts in their acid and sodic forms, as well as MCM-41, for reducing TSNAs in Burley tobaccos. They also studied the decomposition of the TSNAs adsorbed on the catalysts. This study observed that the aluminosilicates were more uniformly distributed on tobacco strands due to their low apparent density. They found a 19% and 30% reduction of TPM and 22% and 35% TSNAs when using MCM-41 and SBA-15, respectively. However, they developed their study by adding 10 \(\upmu\)L of a solution with 5 mg of nitrosamine in 5 mL of methanol to 5 mg of catalyst, previously activated. Once the methanol is evaporated, the resulting concentration of nitrosamine is around 0.33 wt%. This seems a very high catalyst concentration, very far from a possible real application. Moreover, the product may result in a heterogeneous mixture, since not all the catalyst may be wet by the solution. The products were analyzedonly by GC/MS at an inert atmosphere. The experiments reported by these authors, on the decomposition of the NNN adsorbed on these catalysts, are very interesting and constitute a valuable reference for our work. According to [27; 28; 29], the NNN pyrolysis starts by the breaking of N-NO bond, and the intermediate formed reacts through two pathways. The first is the dehydrogenation to give 3-(4,5-dihydro-3H-pyrrole-2-yl) pyridine, and the second is the methylation of the nitrogen atom of the pyridine ring to give 3-(N-methylpyrrolidine-2-yl) pyridine, that can be aromatized to produce 3-(N-methylpyrrol-2-yl) pyridine. The main product is 3-(4,5-dihydro-3H-pyrrole-2-yl) pyridine, that further decomposes to 3-vinylpyridine and 3-pyridinecarbonitrile through the breaking of the C-N and C-C bonds of the five atoms ring. In the presence of zeolites and aluminosilicates of the SBA-15 and MCM-41 type, cyanopyridine was not obtained, but quinoline and isoquinoline were observed. This indicates that the pyrrole ring has not been cracked, but has been rearranged to a more stable structure involving a benzene ring on the quinoline. According to these authors, the decomposition products are not as carcinogenic as the NNN. On another hand, they observed that the catalysts were strongly adhered to the tobacco leaf and did not pass to the smoke. In our group, we have studied the use of aluminosilicates to reduce the toxicity of tobacco. We have also studied the effect of these catalysts on the products derived from the pyrolysis and combustion of the highly toxic compounds present in tobacco smoke. These analyses have been carried out as a function of temperature. Recently, we have studied the effect of such catalysts on different tobacco additives and nicotine [30; 31; 32; 33; 34]. Thus, the objective of the present work, is to study the decomposition of N-nitrosonomic (NNN) in TG/FTIR at a slow heating rate, as well as the fast pyrolysis at different temperatures in an EGA pyrolysis equipment connected in line with a GC/MS. In this way, it is intend to evaluate the nature of the compounds generated when this nitrosamine is heated under inert and oxidizing atmospheres (He and air), emulating the processes of combustion and pyrolysis present in smoking.