Solid-state synthesis of mesoporous MFI zeolite from self-bonded silica pellets

In Situ Recrystallization of Mesoporous Carbon–Silica Composite for the Synthesis of Hierarchically Porous Zeolites

“…Compared with SBA-15, MCSI-0.4 samples also showed meso-structures with P6mm symmetry, as seen in the presence of (100), (110), and (200) diffraction peaks, suggesting that the organic carbon source (furfuryl alcohol) was involved in binding the framework of mesoporous materials during the formation of the mesostructured silica-carbon composites. As shown in Figure 3a, the diffraction peaks of MCSI-0.4 were slightly shifted to higher values, which can be attributed to structural shrinkage during carbonization at high temperature (1023 K) [17,18]. Weaker (100), (110), and (200) diffraction peaks of MCSI-0.4 samples, compared to SBA-15, were the result of introducing an organic carbon source, which caused the structural regularity of the meso-structured silica-carbon composites to decrease.…”

Solid transformation synthesis of zeolites from fly ash

“…27 A dispersion system of FA and trace water was formed during the solid transformation synthesis process, in which aluminosilicate and adsorbed water were the adsorbent and the adsorbate, respectively. The solid phase system entropy increased signicantly due to the dispersion of NaOH powder and the generation of surface bonds on the surface of the aluminosilicate, which led to the formation of an electric eld gradient, a potentiometric gradient and a concentration gradient and promoted the self-diffusion of Na + and OH À , [17][18][19] and aluminosilicate could be depolymerized and rearranged by OH À group.…”

“…These values are in accordance with the data found in the literature. 4,19,23,27 The isotherms can be categorized as type I, indicating the existence of microporous materials. Generally the NaA type zeolite products had micropore structures with one broad capillary condensation step at a p/p 0 value of 0.05-0.95, representing the broad pore size distribution normally observed with NaA type zeolites.…”

“…ZSM-5, ZSM-35, NaA, NaX, NaY zeolite, mordenaite and SOD have been successfully synthesized using the solid transformation method in a trace water system and a dry power system from y ash. [17][18][19][20][21][22] However, relatively few data are available on the effect of the synthesis conditions of FA zeolites on the characterization and adsorption performance using the solid transformation system.…”

Synthesis of a multi-branched dandelion-like SAPO-11 by an in situ inoculating seed-induced-steam-assisted conversion method (SISAC) as a highly effective hydroisomerization support

“…An alternative to the conventional hydrothermal synthesis (CHT) method is steam-assisted conversion (SAC), one of the typical dry gel conversion (DGC) methods for zeolite synthesis. This method has recently attracted increasing interest for the synthesis of hierarchical zeolites (HSZs) [19][20][21] and superne zeolites. [22][23][24] Under these conditions, the zeolite precursor mixtures are completely dried before they are converted by steam, and such a quasi-solid-state has proven helpful against phase separation and provides an ideal condition for massive nucleation.…”