In-silico screening of Pt-based bimetallic alloy catalysts using ab initio microkinetic modeling for non-oxidative dehyd
- PDF / 624,678 Bytes
- 7 Pages / 612 x 792 pts (letter) Page_size
- 24 Downloads / 162 Views
Research Letter
In-silico screening of Pt-based bimetallic alloy catalysts using ab initio microkinetic modeling for non-oxidative dehydrogenation of ethanol to produce acetaldehyde Fatima Jalid*, Renewable Energy and Chemicals Laboratory, Department of Chemical Engineering, Indian Institute of Technology Delhi, Hauz Khas, Delhi, 110016, India; Department of Chemical Engineering, National Institute of Technology Srinagar, Srinagar, Jammu and Kashmir 190006, India Tuhin S. Khan*, and M. Ali Haider, Renewable Energy and Chemicals Laboratory, Department of Chemical Engineering, Indian Institute of Technology Delhi, Hauz Khas, Delhi, 110016, India Address all correspondence to Tuhin S. Khan and M. Ali Haider at [email protected] and [email protected] (Received 31 October 2018; accepted 9 January 2019)
Abstract Ab initio microkinetic modeling was performed to study ethanol conversion to acetaldehyde on Pt-based bimetallic alloys in a non-oxidative environment. Alloying Pt with Au, Ag, Cu, Co, Ni, Zn, Cd, Al, Ga, In, Tl, Ge, Sn, Pb, As, and Sb showed an increase in product turnover by at least an order of magnitude compared with Pt at 423 K. This was correlated to the increased stabilization of CH3CHO species over these alloys. Among the alloy candidates; Pt3Cu, Pt3Zn, Pt3Ga, Pt3Ge, Pt3Sb, and Pt3Pb were found to be more active than Pt.
Introduction Non-oxidative dehydrogenation (NODH) of alcohols to produce aldehydes and ketones is considered to be an efficient and safer process as compared with its oxidative counterpart. With less propensity for catalyst deactivation,[1] the process may be adapted for new applications in biorenewable transformations. NODH of ethanol to acetaldehyde was first experimented on Cu-based alloy catalysts using Cr and Co as promoters at 573 K.[2] Shan et al.[3] utilized Pt along with Cu to synthesize PtCu alloys for the dehydrogenation of methanol in a non-oxidative manner at a relatively low temperature (T = 523 K). Wang et al.[4] have conducted experimental as well as theoretical studies to explain the increase in the activity of 1% Pt-Cu single atom alloy catalysts as compared with pure Cu for the NODH reaction. In a recent study on ethanol NODH over the bimetallic NiCu, Shan et al.[1] observed a significant increase in the activity as well as stability of the Cu catalyst on adding Ni, owing to the lesser Cu sintering in the presence of Ni and lower apparent activation barrier over NiCu catalyst as compared with pure Cu. For the NODH of secondary alcohols, Kon et al.[5] studied dehydrogenation of 2-octenol over 11 different transition metals; Ag, Cu, Pt, Pd, Rh, Ru, Ni, Au, Re, Ir, and Co, where alumina-supported Pt metal nanoclusters were found to be the most efficient catalyst. In a similar work, an array of transition metal catalysts on different supports were tested for the dehydrogenation and coupling of 1-octanol
* Equal first author contribution.
and Pt/SnO2 exhibited the maximum activity,[6] wherein SnO2 aided the activation of the carbonyl group of aldehyde for coupling. In anothe
