Thermodynamic optimization of bromine-mediated propane dehydrogenation system for efficient propylene and hydrogen production

Abstract

Conventional propane dehydrogenation processes face critical limitations in energy intensity and byproduct valorization. This study proposes an innovative bromine-mediated oxidative dehydrogenation system for synergistic propylene and hydrogen coproduction, addressing these challenges through thermochemical integration and waste heat recovery. A multi-stage reaction pathway coupled with electrothermal activation of hydrogen bromide regeneration enables efficient energy cascading and byproduct utilization. Rigorous thermodynamic modeling, validated via Aspen Plus simulations, systematically evaluates system performance under design and off-design conditions using multi-dimensional metrics. The optimized configuration achieves 82.69% propane conversion with 76.68% hydrogen recovery efficiency, attaining 9.52% overall energy efficiency - a 2.63 percentage-point enhancement through thermal recovery integration. Off-design analysis indicates that elevated pressure and increased bromine-to-propane molar ratio enhance propylene selectivity and energy efficiency, while higher bromination temperatures reduce propane conversion rates and energy performance. Solar power-assisted operation demonstrates economic viability, lowering propylene production costs by $0.03/kg compared to conventional methods. This study fills critical research gaps by providing thermodynamic analysis and valuable insights into energy performance, thereby demonstrating considerable theoretical and practical significance.