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

Liquid phase oxidation of cyclopentanone over metal-free carbon catalysts

Dana Gašparovičová, Milan Králik, Blažej Horváth, Tomáš Soták, and Pavol Hudec

Institute of Organic Chemistry, Catalysis and Petrochemistry, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Bratislava, Slovakia

E-mail: dana.gasparovicova@stuba.sk

Received: 6 July 2023  Accepted: 13 May 2024

Abstract:

Oxidation of cyclopentanone (CPO) was studied over metal-free carbon catalysts in solvent-free conditions. Norit SX plus (900 m² g⁻¹) and Vulcan XC72 (240 m² g⁻¹) were used as pristine materials. Catalysts were prepared by activation in nitrogen and by treatment with urea, calcined in nitrogen at 500 °C and 950 °C. SEM, EDX, XPS, X-ray powder diffraction, nitrogen adsorption–desorption isotherms, acid–base titration, FTIR and Raman techniques were used for characterization. Catalytic tests carried out at 0.45 MPa and 80–110 °C enabled to find the best results: 30% selectivity to glutaric acid (GA) and 3% to succinic acid at 25% conversion of CPO, over Vulcan type catalysts. A low activity, selectivity and strong deactivation of Norit type catalysts can be ascribed to a higher specific surface in a disordered arrangement providing a high concentration of unselective catalytic sites. A higher extent of side reactions can yield in higher molar mass products, which stick on the surface and block catalytic sites. Optimum amount of accessible planar domains, represented by graphene and/or graphitic plates with some disorders present in Vulcan type catalysts classified them superior to Norit catalysts. A redox reaction scheme of oxidation of CPO to GA is also proposed.

Graphical abstract

Keywords: Cyclopentanone; Oxidation; Carbon catalysts; Glutaric acid

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-024-03517-z

Chemical Papers 78 (10) 5943–5960 (2024)