Single-point magnetic resonance imaging study of water adsorption in pellets of zeolite 4A

The water uptake process in commercial type particles of zeolite 4A has bee n studied using a single-point MRI method. True proton density, T-1, T-2, a nd T-2* relaxation times were obtained with submillimetric resolution, over coming the restrictions of short T-2* signals, The molecular mobility in no nequilibrium conditions has been characterized by relaxation time mapping. A clear reduction of the water sorption rate was observed by comparing MRI profiles of a loosely packed bed and gravimetric measurements of spread par ticles from the same sieved zeolite batch. (C) 1999 academic Press.