Absolute Quantification of Water in Microporous Solids with 1H Magic Angle Spinning NMR and Standard Addition

Zeolites are microporous materials driving industrial scale adsorption, ion exchange, and catalytic processes. Their water content dramatically impacts their properties, but its quantification with Karl Fisher titration or thermal gravimetric analysis is problematic. When standard addition of water is combined with H-1 magic angle spinning (MAS) NMR detection, absolute quantification of water in microporous materials becomes possible. The method was demonstrated on five different, commercially available zeolites.