コンノ ヒロキ
Konno Hiroki
今野 大輝 所属 東邦大学 理学部 生命圏環境科学科 職種 准教授 |
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論文種別 | 原著 |
言語種別 | |
査読の有無 | 査読あり |
表題 | Selective synthesis for light olefins from acetone over ZSM-5 zeolites with nano- and macro-crystal sizes |
掲載誌名 | 正式名:Applied Catalysis A: General ISSNコード:0926-860X |
巻・号・頁 | 403(1-2),183-191頁 |
著者・共著者 | Teruoki Tago,Hiroki Konno,Mariko Sakamoto,Yuta Nakasaka,Takao Masuda |
発行年月 | 2011/08/22 |
概要 | Production of light olefins such as ethylene, propylene and isobutylene from acetone was examined over ZSM-5 zeolites. These light olefins are produced from acetone over the acid sites of the zeolite via a series of consecutive reactions where olefins such as ethylene and propylene are obtained by cracking of isobutylene produced from aldol condensation products of acetone. Macro- and nano-sized ZSM-5 zeolites were prepared by conventional hydrothermal and emulsion methods, respectively, and the ZSM-5 zeolites with nearly the same acidity and BET surface area were obtained regardless of the crystal sizes. From SEM observations, the crystal sizes of the zeolites were approximately 2000 nm and 30-40 nm. These zeolites with different crystal sizes were applied to light olefins synthesis from acetone, and the effect of crystal size on catalytic activity and stability was investigated. As compared with the macro-seized zeolite, the nano-sized zeolite exhibited a high activity over a long lifetime. However, because the nano-sized zeolite possesses a large external surface area, undesirable reactions to form aromatics from the produced light olefins occurred on the acid sites located near the external surface. To inhibit aromatics formation, selective deactivation of the acid sites located near the outer surface of the zeolite was achieved via the catalytic cracking of silane (CCS) method using diphenyl silane (DP-silane). The CCS method was effective in deactivating the acid sites located near the external surface of the ZSM-5 zeolite. Moreover, the nano-size zeolite after the CCS treatment using DP-silane exhibited high olefins and low aromatics yields under high acetone conversion conditions. © 2011 Elsevier B.V. All rights reserved. |
DOI | 10.1016/j.apcata.2011.06.029 |