(235g) Effect of CO2 Source and Concentration on the Catalyst Performance and Economics of Ethane Oxidative Dehydrogenation to Ethylene

Southern Research, in partnership with DOE/NETL is developing a novel, low-cost mixed oxide catalyst for low temperature ethylene production process using CO₂, notably from coal-fired flue gas and readily available, low cost ethane as raw materials. The proprietary catalyst has been screened from a series of rationally synthesized catalysts and exploits CO₂ as a ‘soft’ oxidant to dehydrogenate ethane to ethylene at high selectivity (oxidative dehydrogenation). The catalyst has been tested using two different CO₂ concentration levels in the feed: (a) diluted flue gas (12-14% CO₂) and (b) captured CO₂ (95%). Multiple cycle laboratory scale catalytic runs have been conducted using pure ethane and CO₂ at these two concentration levels. Each cycle constituted 7 hr of continuous run and 1 hr of regeneration. The catalyst has also been tested using several flue gas impurities, such as, SO_x, NO_x, O₂, H₂O at levels present in environmentally regulated coal fired flue gas. A techno-economic and life cycle assessment has been conducted using the laboratory scale results and considering two CO₂ concentration levels mentioned above. The economics looks competitive even with partial co-product (CO) credit. CO₂ cost was found to be one of the major drivers in the captured CO₂ case. The LCA study showed up to 57% reduction in GHG emission compared to the state-of-the-art alternative case. The presentation will highlight the impacts of CO₂ source/concentration on catalyst performance, economics and life cycle assessment.