Testing of minerals and industrial by-products as oxygen carriers for chemical-looping combustion in a circulating fluidized-bed 300Â W laboratory reactor

► Over 85 h of continuous operation with ilmenite oxygen carrier; high but incomplete fuel conversion. ► Iron oxide scale (IOS) oxygen-carrier experiments were conducted for 37 h with moderate fuel conversion. ► Problems with IOS particles were particle agglomeration and high attrition rate. ► Both tested oxygen carriers are suitable for use in chemical-looping combustion though with some drawbacks.