The family of alkenyl benzene molecules, including styrene and its heavier derivatives, serves as important monomers for rubber and plastic production. The current method of alkenyl benzene production, catalytic dehydrogenation of alkyl benzenes, is burdened by high energy usage and equilibrium limitations, leading to significant CO2 emissions and high operating costs. Our research introduces a chemical looping oxidative dehydrogenation (CL-ODH) approach, using a multifunctional mixed metal oxide redox catalyst, which features higher yields and substantial emissions reduction compared to conventional catalytic dehydrogenation. We report a detailed technoeconomic comparison between CL-ODH and conventional dehydrogenation processes for multiple alkyl benzene feedstocks. This comprehensive analysis, based on laboratory-scale experimental data, evaluates energy consumption, CO2 emissions, capital and operating costs, and projected gross margins for both approaches. The study reveals that for each feedstock analyzed CL-ODH could reduce energy consumption by at least 40% and cut CO2 emissions by the same margin compared to current methods, while giving a more than 120% increase in gross margin. Relative to styrene, greater improvements are seen in single-pass yields for the challenging-to-produce heavier alkenyl benzene monomers for CL-ODH. This suggests even higher potential energy savings for these materials. Meanwhile, catalyst optimizations were conducted which include selectivity improvement via a promoted catalyst shell and tailorable heats of reaction using different mixed metal oxides.
