ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Nanoscale lanthanum oxide catalysts for self-condensation of acetone: preparation via self-assembly on anodic aluminum oxide, structure, and properties

Lin Wang, Zhe Chen, Xiao-Yue Wang, and Chang-Hai Du

School of Chemical Engineering, Changchun University of Technology, Changchun 130012, Jilin, China

E-mail: duchanghai@ccut.edu.cn

Abstract: A novel structured La₂O₃/AAO solid base catalyst was prepared by supporting lanthanum oxide (La₂O₃) on the surface of anodic aluminum oxide (AAO) under hydrothermal conditions. Catalytic activity of the catalyst was tested using self-condensation of acetone to diacetone alcohol as a probe reaction. The conversion of acetone reached 4.14 % with the diacetone alcohol selectivity of 98 %. The catalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy disperse spectroscopy (EDS), thermogravimetric analysis (TGA), N₂ adsorption- desorption (BET), and temperature programmed desorption (CO₂-TPD). XRD patterns and SEM images indicated that La₂O₃ nanoscale particles with high crystallinity were uniformly distributed over the AAO surface. The results of CO₂-TPD showed that the calcination temperature led to the formation of medium-strength basic sites, strong basic sites, and to an increase of the basic strength. The strong basic sites and large basic strength are an important factor that influences the catalytic activity in the self-condensation of acetone to diacetone alcohol.

Keywords: La2O3/Al2O3 catalyst – anodic aluminum oxide – self-condensation – acetone – diacetone alcohol – catalytic distillation

Full paper is available at www.springerlink.com.

DOI: 10.1515/chempap-2015-0186

Chemical Papers 70 (2) 137–143 (2016)