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

Highly effective CuO catalysts synthesized by various routes for discoloration of methylene blue

Qian Liu, Qingwen Wang, Wenyong Deng, Lei Gong, Aiqin Dong, Changxiang Liu, Runying Dai, Xigen Huang, and Zhong Huang

College of Science, Jiangxi Agricultural University, Nanchang, People’s Republic of China

E-mail: lchxiang@126.com

Received: 7 June 2019  Accepted: 1 October 2019

Abstract:

A series of CuO catalysts were fabricated through hydrothermal process, thermal decomposition of the precursors of CuC₂O₄ synthesized by soft reactive grinding route and oxalate-gel co-precipitation method, respectively. The discoloration of methylene blue in the presence of H₂O₂ was selected as the activity test model reaction. The as-prepared catalysts were characterized by powder X-ray diffraction, scanning electron microscopy, infrared diffuse reflectance spectrum, and N₂-adsorption analysis. The CuO obtained from calcination of dry-grinding-derived oxalate precursor has better catalytic performance than those prepared by conventional wet-chemical method. Examination of the structural characterization shows that the small particle size and relatively high surface area are the main reasons for its excellent activity. Moreover, the pseudo-first-order kinetics model was also employed to understand the discoloration behavior of grinding-derived CuO and the activation energy was calculated to be 56.5 kJ mol⁻¹. The current preparation mechanism of solid-state synthetic technique was also proposed by tracking the precursor structure.

Keywords: CuO; Soft reactive grinding route; Methylene blue; Kinetics

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-019-00950-3

Chemical Papers 74 (4) 1113–1121 (2020)