Low-Temperature Propylene Epoxidation Activity of CuO–CeO2 Catalyst with CO + O2: Role of Metal–Support Interaction on the Reducibility and Catalytic Property of CuOx Species | Sciact - CRIS-system of Boreskov Institute of Catalysis

Low-Temperature Propylene Epoxidation Activity of CuO–CeO2 Catalyst with CO + O2: Role of Metal–Support Interaction on the Reducibility and Catalytic Property of CuOx Species Full article

Journal

The Journal of Physical Chemistry C
ISSN: 1932-7447 , E-ISSN: 1932-7455

Output data

Year: 2020, Volume: 124, Number: 26, Pages: 14131-14146 Pages count : 16 DOI: 10.1021/acs.jpcc.0c00777

Tags

Mixtures, Catalysts, Redox reactions, Alkyls, Organic reactions

Authors

Baidya Tinku ¹ , Mazumder Tanmoy ¹ , Koltunov Konstantin Yu. ^2,3 , Likhar Pravin R. ¹ , Clark Adam H. ⁴ , Tiwari Khushubo ⁵ , Sobolev Vladimir I. ² , Payra Soumitra ⁶ , Murayama Toru ⁷ , Lin Mingyue ⁷ , Bera Parthasarathi ⁸ , Roy Sounak ⁶ , Biswas Krishanu ⁵ , Safonova Olga ⁴ , Srinivasa Rao Bolla ¹ , Haruta Masatake ⁷

Affiliations

1	Catalysis & Fine Chemicals Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India
2	Boreskov Institute of Catalysis, Novosibirsk 630090, Russia
3	Novosibirsk State University, Novosibirsk 630090, Russia
4	Paul Scherrer Institute, 5253 Villigen, Switzerland
5	Department of Materials Science and Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
6	Birla Institute of Technology and Science Pilani, Hyderabad Campus, Hyderabad 500078, India
7	Department of Applied Chemistry, Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan
8	Surface Engineering Division, CSIR-National Aerospace Laboratories, Bengaluru 560017, India

Funding (2)

1	Federal Agency for Scientific Organizations	0303-2016-0006 (V.44.1.6)
2	Department of Science and Technology

Epoxidation of propylene into propylene oxide (PO) in the gas phase is a highly challenging reaction. Cu-based catalysts have been active for this reaction, but the state of Cu as an active species is still debatable. In this paper, we report the propylene epoxidation activity of solution combustion synthesized Cu/CeO2 catalysts with the CO + O2 mixture at low temperatures (50–100 °C) peaking at ∼80 °C. The highest PO yield was obtained with 20–25% Cu loading in CeO2. In contrast, the reaction over the catalyst containing nonreducible support such as Cu/SiO2 occurred above 170 °C. Detailed structural characterization indicated two types of Cu species such as Cu2+ partly (∼3%) dissolved in CeO2 forming a CuxCe1–xO2−δ phase and the remaining amount formed highly dispersed CuO as a separate phase. Thus, the highest activity relates to the optimum presence of CuO along with Ce1–xCuxO2−δ. The reducibility of the Cu species in two phases was significantly shifted toward lower temperatures, indicating strong electronic interaction between the two phases. The substituted Cu2+ was reduced first, and then, the bulk CuO reduction was initiated. In situ spectroscopic studies showed Cu+ formation from Cu2+ over Cu/CeO2 catalysts even at room temperature unlike in CeO2 or CuO + CeO2 physical mixtures, indicating strong electronic interaction between Ce1–xCuxO2−δ and CuO phases on CO adsorption in the Cu/CeO2 catalyst. It is proposed that substituted Cu2+ along with Ce4+ is reduced easily, and then, Ce3+ promotes the reduction of the interfacial CuO phase that might donate active oxygen species for epoxidation reaction.

Baidya T. , Mazumder T. , Koltunov K.Y. , Likhar P.R. , Clark A.H. , Tiwari K. , Sobolev V.I. , Payra S. , Murayama T. , Lin M. , Bera P. , Roy S. , Biswas K. , Safonova O. , Srinivasa Rao B. , Haruta M.
Low-Temperature Propylene Epoxidation Activity of CuO–CeO2 Catalyst with CO + O2: Role of Metal–Support Interaction on the Reducibility and Catalytic Property of CuOx Species
The Journal of Physical Chemistry C. 2020. V.124. N26. P.14131-14146. DOI: 10.1021/acs.jpcc.0c00777 WOS Scopus РИНЦ AN OpenAlex

Submitted:	Jan 28, 2020
Accepted:	Jun 3, 2020
Published online:	Jun 4, 2020
Published print:	Jul 2, 2020

Web of science:	WOS:000547455300008
Scopus:	2-s2.0-85089935305
Elibrary:	45338657
Chemical Abstracts:	2020:1081218
OpenAlex:	W3033018888

DB	Citing
Web of science	25
Scopus	26
Elibrary	24
OpenAlex	26