[en] The work presented here consists in a combination of different aspects of Nuclear Magnetic Resonance, focused on providing a reliable tool for the optimization of chemical processes, via the on-line monitoring of catalytic reactions. For that purpose, the following decomposition in the presence of metal containing porous media as a catalyst, was studied as a model reaction: 2H₂O₂(liquid)→ 2H₂O+O₂(gas). The results presented along this work include: the feasibility of using the time dependence of the effective diffusion coefficient in the vicinity of the catalysts to monitor the decomposition with relatively high temporal resolution for several hours; the possibility of making use of the influence of two-site chemical exchange between protons in water and hydrogen peroxide on the transverse relaxation rate, together with p_H, to obtain a quantification of the H₂O₂ concentration during the reaction, in the liquid surrounding the catalyst; the use of the chemical exchange as a source of contrast in NMR Imaging, providing a tool for monitoring the reaction with spatial resolution inside the porous particle. Possible extensions of the results and experiments to different kind of samples and set ups are suggested at the end of the work. (orig.)