Intensified Ethylene Production via Chemical Looping through an Exergetically Efficient Redox Scheme

Ethylene production via steam cracking of ethane and naphtha is one of the most energy and emission-intensive processes in the chemical industry. High operating temperatures, significant reaction endothermicity, and complex separations create hefty energy demands and result in substantial CO₂ and NO_x emissions. Meanwhile, decades of optimization have led to a thermally efficient, near-"perfect" process with ∼95% first law energy efficiency, leaving little room for further reduction in energy consumption and CO₂ emissions. In this study, we demonstrate a transformational chemical looping-oxidative dehydrogenation (CL-ODH) process that offers 60%-87% emission reduction through exergy optimization. Through detailed exergy analyses, we show that CL-ODH leads to exergy savings of up to 58% in the upstream reactors and 26% in downstream separations. The feasibility of CL-ODH is supported by a robust redox catalyst that demonstrates stable activity and selectivity for over 1,400 redox cycles in a laboratory-scale fluidized bed reactor.