Co-Ni/Al₂O₃ oxygen carrier for fluidized bed chemical-looping combustion

Chemical-looping combustion (CLC) has received growing interest as an efficient combustion technology for the capture of CO₂ and the substantial reduction of NO_x emissions from fossil fuel based power generation. The development of a bimetallic Co-Ni/Al₂O₃ oxygen carrier suitable for fluidized bed CLC was presented. The addition of Co enhanced the reducibility of the oxygen carrier by influencing the state of the surface minimizing the formation of nickel aluminate. The Co-Ni/Al₂O₃ particles were highly reactive and stable over multiple reduction/oxidation cycles. The addition of Co also inhibited metal particle agglomeration by maintaining consistent metal dispersion during the cyclic reduction/oxidation processes. The SEM images of a fresh and a used carrier sample evidences similar distribution of the metal crystallites suggesting minimum agglomeration of the nickel species at high temperature CLC processes. This is an abstract of a paper presented at the AIChE Annual Meeting (Salt Lake City, UT 11/4-9/2007).