Highly Dispersed Copper Species within SBA-15 Introduced by the Hydrophobic Core of a Surfactant Micelle as a Carrier and Their Enhanced Catalytic Activity for Cyclohexane Oxidation
详细信息 查看全文
- 作者：Jinlou Gu ; Ying Huang ; S. P. Elangovan ; Yongsheng Li ; Wenru Zhao ; Iijima Toshio ; Yasuo Yamazaki ; Jianlin Shi
- 刊名：Journal of Physical Chemistry C
- 出版年：2011
- 出版时间：November 3, 2011
- 年：2011
- 卷：115
- 期：43
- 页码：21211-21217
- 全文大小：912K
- 年卷期：v.115,no.43(November 3, 2011)
- ISSN：1932-7455
文摘
Highly dispersed copper species were successfully coated onto the inner surface of the rodlike mesoporous SBA-15 silica by a newly developed strategy. The hydrophobic core of the surfactant micelle in the as-synthesized SBA-15 was effectively employed as a carrier for the hydrophobic precursors of copper acetyl acetonate (Cu(acac)2) during hydrothermal treatment (HT) before surfactant removal, and the copper-derivated catalysis centers within SBA-15 were strategically generated on pyrolysis. Characterizations of the synthesized samples by a series of techniques such as X-ray diffraction (XRD), transmission electron microscopy (TEM), Brunauer鈥揈mmett鈥揟eller (BET), electron paramagnetic resonance (EPR), temperature-programmed reduction (TPR), UV鈥搗is, X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma atomic emission spectroscopy (ICP鈥揂ES) manifested that about 0.19鈥?.85 wt % copper was directly introduced and dispersed into the inner surface of the SBA-15 pore network. While there were few studies, if any, to utilize synthetic copper catalysts for the selective oxidation of cyclohexane oxidation, it was found that currently synthesized Cu-SBA-15 demonstrated very interesting catalytic properties for this industrially important reaction. Under the optimized reaction condition at an oxygen pressure of 1 MPa and a temperature of 120 掳C for 7 h, the conversion of cyclohexane to the target products was higher than 11%; meanwhile, the total selectivity to cyclohexanol and cyclohexanone satisfactorily reached ca. 80%.