Keggin type heteropoly acid, encapsulated in metal-organic framework: A heterogeneous and recyclable nanocatalyst for selective oxidation of sulfides and deep desulfurization of model fuels

Three hybrid composite materials were prepared by H3PW12O40 (PW), H3PMo12O40 (PMo) and H3SiW12O40 (SiW) into the porous metal-organic framework Cu-3(BTC)(2) (HKUST-1). The catalyst was characterized by various techniques including powder X-ray diffraction, FT-IR, SEM/EDX and successfully used for the selective oxidation of sulfides. Cyclic voltammetry was further used for the investigation of the redox behavior of this catalyst. Catalytic oxidation of the sulfur-containing model oil was also studied under optimized conditions. The oxidation desulfurization (ODS) system containing the catalyst could be recycled at least four times with only a slight decrease in the catalytic performance. The stability of the catalyst after the catalytic cycles was confirmed by several techniques. (C) 2014 Elsevier B.V. All rights reserved.