Stabilization of Extra‐Large‐Pore Zeolite by Boron Substitution for the Production of Commercially Applicable Catalysts

Abstract

Stable extra-large-pore zeolites are desirable for industrial purposes due to their ability to accommodate bulky reactants and diffusion through channels. Although there are several extra-large pore zeolites reported, stable ones are rare. Thus, their stabilization is a feasible strategy for industrial applications. Here, an extra-large-pore zeolite EWT with boron substitution is presented, and the resulting zeolite B-RZM-3 increased the thermal stability from 600 °C in its silica form to 850 °C. The crystal structure, determined by combining continuous rotation electron diffraction (cRED) and powder X-ray diffraction (PXRD), shows that B atoms preferentially substitute the interrupted (HO)T(OT) 3 (Q 3 ) sites and are partially converted into 3-coordination to relax framework deformation upon heating. After Al-reinsertion post-treatment, Al-B-RZM-3 shows higher ethylbenzene selectivity and ethylene conversion rate per mol acid site than commercial ZSM-5 and Beta zeolite in benzene alkylation reaction. Synthesizing extra-large-pore zeolite in borosilicate form is a potential approach to stabilize interrupted zeolites for commercial applications.

Crystalline Zeolite Layers on the Surface of Titanium Alloys in Biomedical Applications: Current Knowledge and Possible Directions of Development

“…These materials consist of tetrahedrons of the general formula MO 4 where M is Al or Si in natural zeolites. In the synthetic ones, M can stand for instance for Ti, Zr, B, or Ge [5][6][7][8][9]. Currently, the Structure Commission of the International Zeolite Association (IZA-SC) has recognized 247 unique types of zeolite network structures [10].…”