Pt/CeO₂ as Catalyst for Nonoxidative Coupling of Methane: Oxidative Regeneration

Abstract

Direct nonoxidative coupling is a promising route for methane upgrading, yet its commercialization is hindered by the lack of efficient catalysts. Pt/CeO2 catalysts with isolated Pt species have attracted an increasing amount of interest in recent years. Herein, we studied the catalytic role and evolution of isolated Pt centers on CeO2 prepared by flame spray pyrolysis under the harsh reaction conditions of nonoxidative methane coupling. During the reaction at 800 °C, the isolated Pt sites sinter, leading to a loss of the ethylene and ethane yield. The agglomerated Pt can be redispersed by using an in situ regeneration strategy in oxygen. We found that isolated Pt centers are able to activate methane only at the initial reaction stage, and the CePt5 alloy acts as the active phase in the prolonged reaction.

Non-Oxidative Coupling of Methane Catalyzed by Heterogeneous Catalysts Containing Singly Dispersed Metal Sites

“…Recently, Emiel and co-workers also synthesized the isolated dispersed Pt/CeO 2 catalyst via flame spray pyrolysis under the harsh conditions of an NOCM reaction [83]. The sintering of isolated Pt sites during the reaction at 800 • C led to a loss in the yield of C 2 products.…”

Role of Oxidizing Conditions in the Dispersion of Supported Platinum Nanoparticles Explored by Ab Initio Modeling

“…The surface properties, stability, and poisoning resistance of platinum make it an exceptional catalyst for a wide variety of industrial processes, including selective hydrogenation and dehydrogenation reactions, , water–gas shift for H 2 production, , nonoxidative coupling of methane, , dealkylation of toluene, , isomerization of hydrocarbons, , oxidation of CO and NO, and electrocatalytic hydrogen evolution and oxygen reduction reactions, among others.…”