Glycerol molecules in nano channels of NaY and USY zeolites

Abstract

Rich nano channels of zeolites give themselves excellent adsorption capacity, which have been widely used in environmental protection and catalysis. The adsorption process and existential form of the molecules in the nano channels are affected by the spatial confinement and regularity of the nanoporous channels. In this work, the adsorption of glycerol molecules in NaY and USY zeolites nano channels were studied. The results showed that adsorption quantity of glycerol molecules in nano channels and formation of glycerol molecular clusters were significantly affected by the static adsorption time. Due to the spatial confinement of the nanoporous channel, the H⋯O bond length and the HO⋯O angle were reduced. TEM scanning results indicated that the size of glycerol molecular cluster in nano channel was smaller than that of the bulk ones outside nano channel. 1H NMR results suggested that the spin motion of the hydroxyl hydrogen bond was enhanced. Computer simulation results showed that intermolecular hydrogen bonds were formed between the glycerol molecular cluster and oxygen atoms on the channel wall. This work may show new light on the study of molecular immobilization in spatial confinement.