Antisolvent Precipitation for the Synthesis of Monodisperse Mesoporous Niobium Oxide Spheres as Highly Effective Solid Acid Catalysts

作者：Li Cheng Chao; Dou Jian; Chen Luwei; Lin Jianyi; Zeng Hua Chun^*

来源：ChemCatChem, 2012, 4(10): 1675-1682.

DOI：10.1002/cctc.201100457

• heterogeneous catalysis
• alkylation
• hydrolysis
• mesoporous materials
• niobium

We have developed a low-cost reaction protocol to synthesize mesoporous Nb2O5-based solid acid catalysts with external shape control. In the synthesis, monodisperse glycolated niobium oxide spheres (GNOS) were prepared by means of a simple antisolvent precipitation approach and subsequently converted to mesoporous niobium oxide spheres (MNOS) with a large surface area of 312 m2?g-1 by means of the hydrothermal treatment. The antisolvent acetone used to obtain GNOS was recovered through distillation at high purity. The obtained mesoporous MNOS were functionalized further with sulfate anions at different temperatures or incorporated with tungstophosphoric acid to obtain recyclable solid acid catalysts. These MNOS-based catalysts showed excellent performance in a wide range of acid-catalyzed reactions, such as FriedelCrafts alkylation, esterification, and hydrolysis of acetates. As they are monodisperse spheres with diameters in the submicrometer range, the catalysts can be easily separated and reused.

• 出版日期2012-10
• 单位KAUST