Probing Water Diffusion Inside Crystals of AlPO-5 by PFG NMR and IRM for Heat Storage Applications

Diffusion of water in the aluminophosphates AlPO-5 is studied using a combination of pulsed field gradient NMR and IR microimaging. The concentration profiles measured by the latter allowed to visualize the process of water sorption and propagation into the crystals of AlPO-5. The self-diffusion coefficients obtained by NMR were one order of magnitude higher values compared to corrected ones from the IR microimaging study. The concentration profiles allowed to visualize the process of water sorption and propagation into the crystals of AlPO-5. The obtained results are compared with experimental and simulation data for the water/AlPO-5 system for the literature and discussed in the context of its potential use for heat storage applications.