(231b) General Descriptors for Steering CO2-Assisted Selective C?H/C?C Bond Scission in Ethane
AIChE Annual Meeting
Tuesday, November 15, 2022 - 8:24am to 8:45am
The selective CâH/CâC bond scission in CO2-assisted alkane activation represents an opportunity for simultaneously upgrading greenhouse gas CO2 and light alkanes for the synthesis of value-added syngas, olefins, aromatics and oxygenates. Here, Pd bimetallic (PdMx)-derived catalysts were investigated for ethane-CO2 reactions by combining kinetic analysis, in situ characterization and density functional theory (DFT) calculations. Two types of catalyst structures were identified under reaction conditions, with the PdCox alloy surface favoring ethoxy formation, a critical precursor for further CâC bond scission, and the reaction-induced InOx/Pd interface promoting CâH bond scission. Our results revealed a general strategy to capture the reaction-induced surface configurations and in turn control the selectivity in CâC/CâH bond scission over PdMx-derived catalysts, featuring the interplay of two general descriptors: formation energy of PdMx surfaces and their binding energy to oxygen. Our study provides insight into the rational design of selective catalysts for light alkane-CO2 reactions.