Nanostructured Natural Zeolite: Surface Area, Meso-pore and Volume Distribution, and Morphology

Abstract

Analysis of meso-porosity, morphology, and textural characteristics of a commercial Indian zeolite was done experimentally using a nitrogen (N₂) adsorption isotherm. Scanning electron microscope (SEM) morphology has been described for the nanostructured Indian zeolite (550-nm particle-size grains; pore width 19–22 nm) as well as its surface area and meso-porosity. The detailed surface area, pore volume, and pore size were determined from the adsorption–desorption isotherms of nitrogen measured volumetrically at 77K. To study the reliable pore-size distribution (PSD) both adsorption and desorption curves were used by fitting the data to several well-known adsorption models: Bruaner–Emmett–Teller (BET) model, Barret, Joyner and Halenda (BJH) model, Dollimore and Heal (D-H) model, Horvath–Kawazoe model, and the density functional theory (DFT) model. The sample did not contain any micropores as evident from BJH cumulative pore volume. Further morphology investigated by field emission scanning electron microscopy has shown the tubular crystals.

Keywords:

• BET model
• BJH model
• D-H model
• DFT and morphology
• HK model
• zeolite