Chemical Engineering Journal, Vol.316, 15-23, 2017
A facile method for sodium-modified Fe2O3/Al2O3 oxygen carrier by an air atmospheric pressure plasma jet for chemical looping combustion process
The use of seawater as catalytic agents for hematite (Fe2O3) as oxygen carrier in chemical looping combustion process is attractive, because of its abundance and low cost. Unfortunately, seawater itself with major NaCI compound under reactive species accompanying the volatilization of chlorine-containing gases probably lead to the corrosion on reactors during the combustion process. In this study, the feasibility evaluation of sodium dopants extracted from seawater as an effective catalytic agent via an air atmospheric pressure plasma jet (Air-APPJ) is performed, and as such it is combined with Fe2O3/Al2O3 to assess any possible enhancement on the reduction kinetics. The sodium-contained solutions, NaNO3 ((aq)) and NaCh((aq)), as precursors are used to prepare the sodium dopants due to the evaporation decomposition of water and dissolved salts via plasma discharge reaction. The sodium-modified Fe2O3/Al2O3 oxygen carrier can significantly promote the efficiency of the carbon capture efficiency and CO2 yield. Especially for the NaCI(aq) as precursor in an Air-APPJ system, the high carbon capture efficiency, CO2 molar fraction and CO2 yield around 0.96, 0.95 and 0.91 after fifty redox cycle for the sodium modified Fe2O3/Al2O3 oxygen carrier are achieved. It can be anticipated that the sodium-modified Fe2O3/Al2O3 from seawater by an Air-APPJ system as an oxygen carrier candidate in a reversible CLC process would be notably attractive. (C) 2017 Elsevier B.V. All rights reserved.