石油炼制与化工

• 催化剂 • 上一篇    下一篇

SBA-15铌改性的研究

白向向,沈健,魏田生   

  1. 辽宁石油化工大学石油化工学院
  • 收稿日期:2010-09-10 修回日期:2010-12-15 出版日期:2011-04-12 发布日期:2011-04-12
  • 通讯作者: 沈健

STUDY ON THE NIOBIUM MODIFIED SBA-15

  • Received:2010-09-10 Revised:2010-12-15 Online:2011-04-12 Published:2011-04-12

摘要: 用直接合成和后合成法以及直接合成后草酸处理三种方法制备了铌改性催化剂Nb-SBA-15。采用XRD,BET,FT-IR,DTA方法对样品进行表征。结果表明,直接合成的(Z)-Nb-SBA-15与后合成的 (H)-Nb-SBA-15结构不同。以合成油酸异丙酯为探针反应,对不同方法制备的催化剂及直接合成经草酸处理后催化剂的催化性能进行评价,结果表明,(H)-Nb-SBA-15的活性羟基多,催化活性高,但稳定性差;(Z)-Nb-SBA-15的活性羟基少,催化活性低,但稳定性较好;(Z)-Nb-SBA-15经草酸改性后的催化活性及稳定性均较好。

关键词: 铌, Nb-SBA-15, 酯化, 油酸异丙酯

Abstract: Niobium modified mesoporous molecular sieve catalysts were prepared by three methods: direct synthesis, post-synthesis and direct synthesis-oxalic acid treatment, the prepared catalysts were named as (Z)-Nb-SBA-15, (H)-Nb-SBA-15 and oxalic acid modified (Z)-Nb-SBA-15, respectively. These samples were characterized by XRD, BET, FT-IR and DTA techniques, and the results showed that the structure of (Z)-Nb-SBA-15 was varied from that of (H)-Nb-SBA-15. The catalytic performance of these catalysts was evaluated using synthesis of isopropyl oleate from isopropanol and leic acid as probe reaction. Evaluation results showed that (H)-Nb-SBA-15 had more reactive hydroxyl than (Z)-Nb-SBA-15, thus the catalytic activity of the former was higher than the latter, yet the stability of the latter was better than the former; the catalytic activity and stability of oxalic acid modified (Z)-Nb-SBA-15 were both improved.

Key words: Niobium, Nb-SBA-15, Esterification, isopropyl oleate