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Sulfur-centered phenyl, n-butyl, p-tolyl, and benzyl sulfoniums and sulfides were tested as organic structure-directing agents (SDAs) for the synthesis of crystalline microporous aluminophosphates (AlPOs) over various ranges of gel compositions, hydrothermal treatment temperatures, and crystallization times. Among the investigated compounds, triphenylsulfonium gave single-phase products of ATS-type AlPO and silicoaluminophosphate. Other sulfoniums yielded only non-porous, dense crystalline AlPOs. On the other hand, diaryl sulfides gave a tiny amount of AFI-type AlPO amid tridymite and amorphous phases. Based on the results, it was found to be reasonable that weakly basic sulfide could hardly act as a zeotype SDA due to the low protonation to sulfonium at the present synthesis pH.

Zeolite-templated synthesis of ordered microporous carbons was performed with Ca2+ ion-exchanged Y and beta zeolites, where the conventionally used carbon source gases (e.g., ethylene and propylene) were replaced by various organic solvents, such as methanol, ethanol, isopropanol, acetone, tetrahydrofuran, and diisopropyl ether. The oxygen-containing solvents were fed to the zeolites as carried by N2 gas through a bubbler. Mass spectrometric analyses of the carbonization stream indicated that isopropanol, acetone, tetrahydrofuran, and diisopropyl ether were converted largely to propylene and H2O vapor, while ethanol and methanol to ethylene. The simultaneous generation of H2O and the olefins, without using high-pressure gas cylinders, can be merit in the Ca2+ ion-catalyzed synthesis of zeolite-templated carbons (ZTCs). The approach in this work provides a facile way to produce high quality ZTCs exhibiting excellent micropore orders and high specific capacitances in supercapacitor applications.

Zeolite Y is widely used as an industrial catalyst for catalytic cracking of heavy feedstocks to lighter olefins. However, incorporation of uniform mesoporosity in zeolite Y without compromising the microporous characteristics is required to improve the catalyst efficiency and minimize catalyst deactivation. Here, we report a facile synthesis method for mesoporous zeolite Y (MPY sg ) using seed gel and amphiphilic organosilane, that results in mesoporous zeolite showing a narrow mesopore size distribution (3–4 nm) with high external surface area (110 m 2 g -1 ) and high micropore surface area (654 m 2 g -1 ). During the crystallization of MPY sg , the organosilane acted as a mesopore-generating agent, and the seed gel provided secondary nuclei that created a uniform mesoporous structure in the zeolite Y nanocrystals. Analysis of aluminosilicate precursors collected during the crystallization revealed that the crystallization process starts with a long nucleation period, followed by rapid crystal growth. Due to the highly accessible strong acid sites present on its external surface, MPY sg shows catalytic activity in the decalin cracking reaction higher than that of conventional microporous zeolite Y.