title: Widening Synthesis Bottlenecks: Realization of Ultrafast and Continuous-Flow Synthesis of High-Silica Zeolite SSZ-13 for NOx Removal.
abstract: Characteristics of zeolite formation, such as being kinetically slow and thermodynamically metastable, are the main bottlenecks that obstruct a fast zeolite synthesis. We present an ultrafast route, the first of its kind, to synthesize high-silica zeolite SSZ-13 in 10 min, instead of the several days usually required. Fast heating in a tubular reactor helps avoid thermal lag, and the synergistic effect of addition of a SSZ-13 seed, choice of the proper aluminum source, and employment of high temperature prompted the crystallization. Thanks to the ultra-short period of synthesis, we established a continuous-flow preparation of SSZ-13. The fast-synthesized SSZ-13, after copper-ion exchange, exhibits outstanding performance in the ammonia selective catalytic reduction (NH3 -SCR) of nitrogen oxides (NOx ), showing it to be a superior catalyst for NOx removal. Our results indicate that the formation of high-silica zeolites can be extremely fast if bottlenecks are effectively widened.
authors: Department of Chemical System Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan).
authors: Zhendong
authors: Z
authors: Liu
authors: Toru
authors: T
authors: Wakihara
authors: Kazunori
authors: K
authors: Oshima
authors: Daisuke
authors: D
authors: Nishioka
authors: Yuusuke
authors: Y
authors: Hotta
authors: Shanmugam P
authors: SP
authors: Elangovan
authors: Yutaka
authors: Y
authors: Yanaba
authors: Takeshi
authors: T
authors: Yoshikawa
authors: Watcharop
authors: W
authors: Chaikittisilp
authors: Takeshi
authors: T
authors: Matsuo
authors: Takahiko
authors: T
authors: Takewaki
authors: Tatsuya
authors: T
authors: Okubo
keywords: NOx removal; crystal growth; heterogeneous catalysis; seeded growth; zeolites