Sodium NMR relaxation in mesoporous systems

Abstract We explore the NMR relaxation of 23 Na nuclei in brine confined in mesoporous controlled porous glass. Bi-exponential decays characteristic of the relaxation of the quadrupole sodium nuclei under confinements can be clearly identified and contrasted with the mono-exponential decays observed for motional narrowed bulk brine solutions. The concentration dependence of either of the bi-exponential relaxation times of confined 23 Na nuclei, shows a trend opposite to that in bulk solutions. The understanding of this behavior could be fundamental for inferring sodium dynamics in bound water for oilfield formation evaluation and other applications such as monitoring the quality of building materials.