Ilmenite-type natural ore which is constituted mainly of iron-titanium oxide is an interesting candidate as an oxygen carrier in chemical looping combustion (CLC) process. Its reactivity was investigated using methane as reducing gas and air as oxidizing gas. Experiments were carried out in a coupled thermogravimetric-thermo differential analyzer (TGA-DTA). When temperature increases from 700˚C to 1000˚C, the reaction rate increases by 50 times while the oxygen transfer capacity passes from 1.8% to 12%. TG-DT analyses showed that the overall mass loss due to ilmenite reduction reached at most 12%. It corresponds to 87% of theoretical mass loss due to the transformation of Fe 2 TiO 5 into Fe and TiO 2. It is established that the reduction for the iron-titanium oxides occurs in two steps: Fe 2 TiO 5  FeTiO 3  Fe + TiO 2. The titanium reduction from the state TiO 2 to the stage Ti 3 O 5 was observed as well. This behavior is supported by XRD analysis. Subsequent oxidation of the reduced mineral led to recover the starting oxide. The stability of iron-titanium oxides was established over 35 looping cycles of oxidation-reduction, with an increase of 5% of oxygen transfer capacity and reactivity in the first 5 cycles and after that, ilmenite reactivity remained constant. At high temperatures, catalytic effect of ilmenite on methane decomposition leading to carbon deposition is observed. The deposited carbon participates in the reactivity of the oxide.

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Selective oil agglomeration is used as a physical method to reduce impurities in coal fines. The efficiency of the process depends on many factors. The effects of many operating variables have been examined for different coals and tailings, and the efficiency of the process in coal cleaning has been demonstrated. This study summarizes the work carried out in order to develop coal oil agglomeration as a technique for a cleaner coal-water-fuel slurry production.

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