催化学报

催化学报 ›› 2011, Vol. 32 ›› Issue (1): 172-178.DOI: 10.3724/SP.J.1088.2011.00632

• 研究论文 • 上一篇    下一篇

多金属 ZSM-5 催化剂的制备及其催化氨化合成 2,6-二甲基吡啶

文彦珑, 张月成, 冯成, 张頔, 徐卫华, 赵继全   

  1. 河北工业大学化工学院, 天津 300130
  • 收稿日期:2010-07-24 修回日期:2010-10-22 出版日期:2011-01-13 发布日期:2014-05-22

Preparation of Polymetallic ZSM-5 Catalysts and Their Catalytic Performance for 2,6-Lutidine Synthesis

WEN Yanlong , ZHANG Yuecheng*, FENG Cheng, ZHANG Di , XU Weihua, ZHAO Jiquan   

  1. School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China
  • Received:2010-07-24 Revised:2010-10-22 Online:2011-01-13 Published:2014-05-22

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摘要： 通过掺杂制备了一系列多金属改性的 ZSM-5 催化剂, 并用于丙酮和甲醇氨化合成 2,6-二甲基吡啶的反应中. 在固定床反应器上筛选出催化性能良好的催化剂 6%Pb-0.5%Fe-0.5%Co/ZSM-5(200), 探讨了过渡金属掺杂的促进作用, 并考察了反应温度、氨醇比、酮醇比、水含量和停留时间对反应性能的影响. 结果表明, 该催化剂在常压、450 °C、氨醇摩尔比 2:1、丙酮与甲醇摩尔比 2:1、水含量 40% 和停留时间 5.5 s 的条件下, 反应 20 h 时, 丙酮转化率为 67.6%, 2,6-二甲基吡啶收率可达 40.3%. 在上述条件下连续反应 42 h 后, 催化剂性能有所下降, 此时 2,6-二甲基吡啶收率降至 23%. 利用空气氧化法对催化剂进行在线再生, 可使催化剂性能基本得到恢复. 同时采用 X 射线衍射、N2 吸附和吡啶吸附红外光谱等方法对催化剂失活原因进行了分析.

关键词: 2,6-二甲基吡啶, 甲醇, 丙酮, 氨化, 铅, 铁, 钴, ZSM-5 分子筛

Abstract: A series of modified ZSM-5 catalysts for 2,6-lutidine synthesis through catalytic amination of acetone and methanol were prepared by a transition metal doping method. The catalyst 6%Pb-0.5%Fe-0.5%Co/ZSM-5(200) with good performance in the reaction was selected on a fixed-bed reactor. The reasons for the improvement of the catalyst performance by doping transition metals into ZSM-5 were discussed. The effects of reaction temperature, molar ratio of ammonia to methanol, composition of raw materials, and residence time on the catalytic performance of the catalyst were studied. Acetone conversion and 2,6-lutidine yield reached 67.6% and 40.3%, respectively, when the reaction was run at 450 °C for 20 h under the conditions of atmospheric pressure, the molar ratio of ammonia to acetone to methanol of 2:2:1, the volume content of water of 40%, and the residence time of 5.5 s. With the time extension, the performance of the catalyst got deterioration gradually and the yield of 2,6-lutidine dropped to 23% after a time on stream of 42 h. The catalyst activity could be recovered largely by air oxidation on line. The possible reasons for the deterioration of the catalyst performance were discussed.

Key words: 2,6-lutidine, methanol, acetone, ammoniation, lead, iron, cobalt, ZSM-5 zeolite