In this work different methods of elimination of the organic template remaining in a piece of as-synthesized Si-MCM-41 material have been studied: calcination, and two different extraction processes, with ethanol and with hydrogen peroxide. TGA has been applied in order to analyze and to compare the characteristics of the materials obtained by the three different treatments studied. The textural properties of the samples resulting after the extraction of the template, as well as the resulting hydrothermal stability of the materials, have been evaluated. Finally, the ability of the different samples as tobacco additives in order to reduce tobacco toxicity has been studied. The results show that TGA is an excellent tool for the evaluation of the efficiency of the different treatments applied. It can be concluded that the samples treated with a mixture of HCl/EtOH and with hydrogen peroxide, respectively, are able to be used as tobacco additives. Depending of the experimental conditions for the leaching process, the samples can have hydrothermal stability and activity similar to that of the conventional MCM-41, where the template has been removed by calcination. (C) 2010 Elsevier B.V. All rights reserved.