Influence of the Si/Al Framework Ratio on the Microporosity of Dealuminated Mordenite as Determined from N₂Adsorption

Abstract

Dealuminated mordenites depicting SiO 2 /Al 2 O 3 molar ratios in the range 10-206 were analyzed through adsorption methods. The Type I-IV hybrid shape of the N 2 adsorption isotherms at 76 K on dealuminated mordenites indicated rather high micropore contents, though some amount of mesopores of slit-like geometry was also present. Micropore volumes and sizes were measured through a S , t, and DA-plots, as well as by the NLDFT approach. Results indicated that mordenite dealumination caused micropore opening and widening as well as the emergence of further slit-like mesopores; even though a slight structural collapse toward creation of mesopore zones occurred at high dealumination extents.

Investigation of Thermal and Structural Properties of Nitric, Hydrochloric and Sulphuric Acid-Treated Zeolite

“…SiO2/ Al2O3 ratio of Z sample increased from 5.6 to 9.8, 9.7 and 8.8 in the Z-N, Z-H and Z-S samples, respectively, indicating the removal of the significant amount of aluminum from the zeolite structure. Similar changes were obtained in the literature before [7,9,12,22].…”

“…In order to investigate the influence of 1 M HCl, 1 M H2SO4 and 1 M HNO3 treatments on the crystal structure of zeolite, the XRD patterns of all the samples (Z, Z-N, Z-S and Z-H) are given in Figure 1. [6,7,11]. This could be attributed to partial dealumination and the partial collapse of the zeolite structure (Figure 1).…”

Influence of acid and heavy metal cation exchange treatments on methane adsorption properties of mordenite

“…11,42 Moreover, a decrease in the compensating cation content (Ca, Na, and Mg) is observed. On the other hand, the removal of potassium with HCl solution is at a low rate due to the significant amount of potassium originating from K-feldspar, which is insoluble in HCl solution.…”

Plasmon resonance of gold nanoparticles supported on Y-zeolite in the presence of various co-cations

“…In line with the regular nanometer-scale internal voids, zeolites possess less regular meso-scale porosity [52]. Few-atomic clusters may be located both in the regular crystalline cavities as well as outside of them.…”