• CuO/Al2O3 based oxygen carrier was tested in a 0.5 kWth CLC/CLG plant with swine manure. • Oxygen carrier showed stable reactivity and no agglomeration both in CLC and CLG. • High attrition rate was observed during CLG operation with swine manure. • Ash-alumina interaction was responsible for an accelerated degradation of the oxygen carrier. Chemical Looping (CL) technologies emerge as promising candidates for the thermochemical conversion of organic wastes due to its high operation versatility and inherent CO 2 capture. In CL processes, the oxygen carrier performance is a key aspect, which may be affected by its interaction with ash from the fuel. This work evaluates the evolution of the physico-chemical properties of a CuO/Al 2 O 3 oxygen carrier after being tested for 45 h in a 0.5 kW th unit in both combustion (CLC) and gasification (CLG) modes when feeding swine manure as fuel, which has a high ash content. Minor loss of copper was observed, as well as the oxygen carrier’s reactivity was maintained. In addition, no presence of agglomeration was detected. However, the presence of ash-derived elements inside and outside the oxygen carrier particles contributed to reduce the material’s lifetime and promoted the support degradation. This type of degradation was not previously reported with other fuels, as the CuO/Al 2 O 3 material showed a high stability in different chemical looping processes with methane, syngas, or woody biomass. Therefore, the significant influence of swine manure ash composition on oxygen carrier durability was highlighted, raising the question of whether prolonged operation with other fuels with lower ash content could generate this type of problem. Eventually, the use of an alternative support to Al 2 O 3 was suggested.
Domingos et al. (2026) studied this question.