Carbon anodes for aluminium production are produced from calcined petroleum coke (CPC), recycled anode butts and coal tar pitch (CTP). The CO 2 produced during anode consumption contributes to a substantial amount of the CO 2 footprint of this industrial process. Charcoal from wood has been suggested to partly replace coke in anodes but high porosity, low electrical resistivity and high ash content contributes negatively to final anode properties.In this work, charcoal from Siberian larch and spruce was produced by heat treatment to 800 °C, 1200 °C and 1400 °C and acid-washed with H 2 SO 4 . Acid-washing resulted in reduced metal impurity and the porosity decreased with increasing heat treatment. Pilot anodes were made from CTP, CPC with some additions of spruce and larch charcoal. Another set of pilot anodes were produced using a green binder. Compared to reference anodes, the CO 2 reactivity of anodes containing larch was less affected compared to anodes containing spruce. The green binder was found to be highly detrimental for the anodes' CO 2 reactivity properties. Electrochemical consumption increased for anodes containing both green binder, larch and spruce compared to the reference anode.

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Dimensional and phase changes of four candidate oxygen carrier materials for chemical looping combustion are investigated by dilatometry and high-temperature X-ray diffraction during four redox cycles. NiO/Ni 2 AlO 4 does not exhibit significant dimensional changes during cycling, and it is shown that the support material also contributes to the oxygen carrying capacity. CaMn 0.875 Ti 0.125 O 3 exhibited good chemical stability and small dimensional changes upon redox cycling. Cu 0.95 Fe 1.05 AlO 4 showed a one-dimensional expansion of 9% after the experiments, and significant phase changes were seen. The complex set of reactions occurring during redox cycling of ilmenite (FeTiO 3 ) was shown to be accompanied by dimensional changes, giving non-steady dimensional changes during the oxidation and reduction steps.

The electrochemical de-oxidation process, also called FFC-Cambridge process, has been proposed previously to produce reactive metals and their alloys through reduction of their metal oxides. The process works by introducing metal oxides into a molten salt bath where it is electrolysed to form metal powders offering both economic and environmental benefits over the traditional metal production methods. Within the frame of the EU-financed project SCALE (GA 730105), SINTEF is investigating the optimal parameters of the direct electrolytic reduction of Sc2O3 and Sc2O3-Al2O3 precursors (dross from Al-Sc alloy production), giving Sc and Al-Sc metallic powders, respectively, in a molten CaCl2-based electrolyte at a working temperature of ca. 900 °C. The influence of the applied cathodic potential in the reduction mechanism and in the metal product has been studied.

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