(135a) Development of Unique Trimetallic Copper Iron Manganese Oxygen Carrier for Chemical Looping Combustion

Development of Unique Trimetallic Copper Iron Manganese Oxygen Carrier for Chemical Looping Combustion

William Benincosa^1,2,3 Ranjani Siriwardane¹* Hanjing Tian^1,2 Jarrett Riley^1,2

¹U.S. Department of Energy, National Energy Technology Laboratory, 3610 Collins Ferry Road, P.O. Box 880, Morgantown, WV 26507-0880, USA

²Department of Chemical Engineering, West Virginia University, Morgantown, WV 26505, USA

³Oak Ridge Institute for Science and Education, P.O. Box 117, Oak Ridge, TN 37831, USA

*Corresponding Author: Ranjani.Siriwardane@netl.doe.gov

Chemical looping combustion (CLC) is a novel combustion method that uses oxygen from an oxygen carrier (OC), or metal oxide, to react with a fuel source and produce power/heat and a sequestration ready stream of carbon dioxide. It requires the use of a reactive, robust, inexpensive, and environmentally benign OC. As a result, synthetic OC development has gained interest to improve performance by increasing reactivity while maintaining chemical and mechanical stability.

In our previous studies, a synergetic effect among copper, iron, and manganese mixed metal oxides has demonstrated improved reactivity compared with pure single metal oxides for chemical looping combustion. This observed synergy led to the discovery and development of trimetallic copper iron manganese oxide (CuFeMnO₄). This unique oxygen carrier has demonstrated excellent reactivity and stability during multi-cycle reduction and oxidation experiments using thermogravimetric analysis with online mass spectrometry (TGA-MS). It also possesses excellent resistance to attrition. In addition, this oxygen carrier was synthesized from metal oxide precursors, which is the most economical route to commercialization, and the formation of the dominant reactive phase has been distinguished from its single and bimetallic counterparts. Thus, CuFeMnO₄is an excellent OC candidate for CLC. To gain a deeper understanding of the enhanced reactivity due to the formation of this unique phase, a comprehensive study was conducted to determine the oxygen carrier’s reduction behavior. Experimental TGA-MS data was evaluated with conventional solid-state modeling approaches to identify and compare the reduction mechanism that is attributing to the enhanced performance of the trimetallic OC with its single and bi-metallic counterparts. The kinetic parameters and reduction model obtained from this study were also evaluated in process simulations to obtain information for process scale-up. This work aims to highlight the important milestones that were achieved in the design and development of the novel trimetallic oxygen carrier.