Synthesis of zeolite Beta containing ultra-small CoO particles for ethylbenzene oxidation

Zeolite Beta containing ultra-small CoO particles was synthesized from a one-step hydrothermal process. The synthesis route involves the pre-mixture of hydrofluoric acid with tetraethylammonium hydroxide (in a molar ratio of 1.3-1.5:1) before the addition of a silicon and cobalt source. Investigations by scanning electron microscopy, X-ray diffraction, UV-Vis spectroscopy, X-ray photoelectron spectroscopy, H-2-temperature-programmed reduction and transmission electron microscopy confirm the presence of ultra-small CoO particles in the zeolite Beta structure. The ultra-small CoO particles in zeolite Beta present high stability against both oxidation and reduction atmospheres at high temperatures. The catalytic performance of the CoO-containing zeolite Beta catalysts was compared with other Co-containing zeolites by evaluating ethylbenzene oxidation reactivity. The CoO-containing zeolite Beta exhibits high ethylbenzene conversion and high selectivity to acetophenone and 1-phenylethanol. The high activity of this catalyst system can be attributed to the high dispersion of the ultra-small CoO particles in the Beta structure. (C) 2017, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.