Large Crystals Synthesis of Siliceous Layered Zeolitic PLS‐1 and CDS‐1 Zeolite by Dry Gel Conversion Method

Abstract

The large crystal of siliceous zeolitic layered PLS-1, which is a precursor of CDS-1 zeolite with CDO-type topology, can be successfully prepared by dry-gel conversion (DGC) method from a dry-gel containing layered silicate H-kanemite and tetramethylammonium hydroxide (TMAOH) as an organic structure-directing agent (OSDA), and it allows transform to CDS-1 zeolite by calcination with retaining its large crystal particle. Characterizations of the obtained CDS-1 zeolite reveal the different morphology compared by conventional methods. Its particle is found to be aggregated by an enlarged thickness of layered crystals reflecting a zeolitic precursor of PLS-1. Gradual increases of nitrogen adsorption at around middle pressure and FE-SEM measurements strongly indicate that the obtained particles have many steps and aperture like card-house assembly of layered PLS-1 large crystals.

Synthesis and Catalytic Applications of Advanced Sn‐ and Zr‐Zeolites Materials

“…This feature endows it with great structural diversity. [ 96 ] Generally speaking, silylation agents or metal salts are used to link layer silicates, resulting in targeted 3D interlayer expansion zeolites (Me‐IEZs) ( Figure 10 A ). [ 28 , 97 ] Moreover, the incorporation of metal ions not only expands the pore size but also makes siliceous zeolite functionalized due to the isolated metal ions‐derived Lewis acid sites.…”

“…This feature endows it with great structural diversity. [96] Figure 9. A) Post-synthesizing extra-large-pore Sn-UTL zeolite through structural rearrangement and isomorphous substitution.…”

Advances in the Synthesis of Crystalline Metallosilicate Zeolites via Interlayer Expansion

“…Interlayer-expansion zeolites (IEZs) usually use silylating agents or metal salt to connect layer silicates to novel 3D frameworks [ 35 , 36 , 37 , 38 ], which has led to several new microporous zeolite frameworks, such as ferrierite (FER) from PREFER, the MWW-type framework (MWW) from MCM-22 [ 30 , 38 ], COE-3 (CDO) from RUB-36 [ 39 ], and COE-5 (MFS) from COK-5 [ 40 ]. As the number of microporous zeolite frameworks increases, IEZs are gradually forming an important family of microporous materials [ 41 , 42 , 43 , 44 , 45 , 46 ].…”