催化学报

催化学报 ›› 2013, Vol. 34 ›› Issue (1): 200-208.DOI: 10.1016/S1872-2067(11)60512-3

• 研究论文 • 上一篇    下一篇

陶瓷膜分布器强化氧气氧化苯酚羟基化反应

陈日志*, 包耀辉, 邢卫红, 金万勤, 徐南平   

  1. 南京工业大学材料化学国家重点实验室, 江苏南京210009
  • 收稿日期:2012-11-30 修回日期:2012-12-20 出版日期:2013-01-23 发布日期:2013-01-23

Enhanced phenol hydroxylation with oxygen using a ceramic membrane distributor

CHEN Rizhi *, BAO Yaohui, XING Weihong, JIN Wanqin, XU Nanping   

  1. State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing University of Technology, Nanjing 210009, Jiangsu, China
  • Received:2012-11-30 Revised:2012-12-20 Online:2013-01-23 Published:2013-01-23

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583

被引次数

3

摘要： 采用浸渍法制备CuO/TiO2催化剂, 利用X射线衍射、透射电镜、程序升温还原等技术对催化剂进行了表征, 结果表明, CuO以分散态和晶体两种形式存在, 且与载体有强的相互作用. 以陶瓷膜为分布器控制氧气的进料, 进行了CuO/TiO2催化氧气氧化苯酚羟基化反应. 与直接通入氧气方式相比, 采用孔径为0.5µm的陶瓷膜控制进氧, 可使苯二酚收率提高13%, 这主要是由于采用陶瓷膜作为氧气进料分布器可以提供大量具有微小尺寸的氧气气泡, 提高体积溶氧系数, 增强气液传质效果. 在优化的反应条件下, 苯二酚收率达2.5%. 对使用后的陶瓷膜进行扫描电镜表征, 发现陶瓷膜具有良好的稳定性.

关键词: 苯酚, 羟基化, 氧气, 陶瓷膜, 膜分布器

Abstract: A CuO/TiO2 catalyst was prepared by impregnation and characterized by X-ray diffraction, transmission electron microscopy, and temperature-programmed reduction. Two types of dispersed species formed on the TiO2 surface, which were possibly isolated and polymeric CuO species. The CuO catalyst interacted strongly with the TiO2 support. A porous ceramic membrane was used as a distributor to control the supply of oxygen in phenol hydroxylation over the CuO/TiO2 catalyst. Compared to a direct feed of oxygen without a membrane, the yield of dihydroxybenzene (DHB) increased by 13% using a porous ceramic membrane with a pore size of 0.5 µm as an oxygen distributor. This is because the membrane distributor produced numerous small oxygen bubbles, increasing the volumetric oxygen transfer coefficient and gas-liquid mass transfer. Optimizing reaction conditions resulted in a yield of DHB of 2.5%. Scanning electron microscope observation of the used ceramic membrane showed that it possessed excellent thermal and chemical stability.

Key words: Phenol, Hydroxylation, Oxygen, Ceramic membrane, Membrane distributor