Shinichi Shimizu

Synthesis of Giant Zeolite Crystals by a Bulk-Material Dissolution Technique

Using a quartz glass tube as a bulk silica source under aqueous hydrothermal conditions afforded giant crystals of MFI zeolite about 3 mm in size (see photo). Similar procedures were successfully applied to bulk aluminosilicate ceramics to synthesize large crystals of other zeolites, such as ANA, JBW, CAN, and SOD.

Synthesis of giant zeolite crystals by a bulk material dissolution technique

Using a quartz glass tube as a bulk silica source under aqueous hydrothermal conditions afforded giant crystals of MFI zeolite about 3 mm in size (see photo). Similar procedures were successfully applied to bulk aluminosilicate ceramics to synthesize large crystals of other zeolites, such as ANA, JBW, CAN, and SOD.

Catalytic activity of a zeolite disc synthesized through solid-state reactions

Abstract ZSM-5 zeolite in a disc-shaped form was synthesized by a new method in which reactions occurred in the solid state. The proton form of the zeolite was prepared by ion exchange of the sodium ions of the disc-shaped pellet in hydrochloric acid solution. The catalyst prepared was characterized by SEM, thermogravimetry, nitrogen adsorption and ammonia TPD. High p -xylene selectivity was observed for the new disc-shaped ZSM-5 zeolite catalyst in the alkylation of toluene with methanol. This catalytic feature was attributed to the inherent character of the zeolite, since its structure consisted of inter-grown individual HZSM-5 crystals forming secondary mesopores which promote the high gas permeability of the zeolite disc.

Direct Conversion of Bulk Materials into MFI Zeolites by a Bulk‐Material Dissolution Technique

Publisher Summary This chapter discusses the direct conversion of bulk-materials into MFI Zeolites by a bulk-material dissolution technique. By using a novel synthetic technique, dynamic bulk-material dissolution (DBMD), succeeded in converting glass bulk materials by replacing the glassy part to MFI zeolite crystals from the surface to the inside. A thoroughly converted zeolitic tube and partially converted zeolitic fibers and fabric are prepared with this technique. Seed crystals accelerated crystallization and improved both the coverage and uniformity of the crystals.

Alkylation of toluene with methanol over zeolitedisc catalyst synthesized via solid-state reactions

ZSM-5 zeolite disc was synthesized by a new method in which reactions occurred in the solid state. The hydrogen form of the zeolite was prepared by ion-exchange of the sodium ions of the disc-shaped pellet for hydrogen ions in hydrochloric acid solution. The catalyst thus prepared was characterized by SEM, thermogravimetry, nitrogen adsorption and ammonia TPD. High para-xylene selectivity was observed for the new, disc-shaped ZSM-5 zeolite catalyst in the alkylation of toluene with methanol. This feature was attributed to the inherent character of the catalyst, since its structure consisted of intergrown individual HZSM-5 crystals forming secondary mesopores. This structural arrangement led to a substantial decrease in the outer surface between the adjacent crystals, the probability of secondary reactions therefore being suppressed.

Alkylation of toluene with methanol over a zeolite disc synthesized through solid state reactions

Outstandingpara-xylene selectivity in the alkylation of toluene with methanol was observed for a new, disc-shaped ZSM-5 zeolite catalyst synthesized by solid state reactions.