Unusual adsorption mechanism for carboxylic acid gases by polyamine-intercalated α-zirconium phosphate

Abstract

The adsorption mechanism of gaseous carboxylic acid by diethylenetriamine- or pentaethylenehexamine-intercalated α-zirconium phosphate was examined in detail using XRD and solid-state 13C and 31P NMR. The adsorption of acetic acid, propanoic acid, and butyric acid resulted in the co-intercalation of the carboxylic acid molecules into polyamine-intercalated α-zirconium phosphate to expand their interlayer distance by 0.64–0.97 nm. In the case of formic acid, its adsorption induced the rearrangement of the polyamine molecules within the interlayer space.