Carbothermal reduction, of iron

Carbothermic Reduction of Iron from Iron Titanium Oxide Concentrates in a Thermal Plasma Fluidized Bed... 

The carbothermal synthetic route may also have undesirable side effects. Thus, the carbothermal reduction of iron could yield iron phosphide contaminants, which are difficult to separate and compromise the4V capacity of the material. At this point, MS has been shown to be particularly effective in detecting and quantifying iron phosphide impurities and monitoring changes in the oxidation state of iron. The difference profiles of the Mossbauer spectra provide unequivocal identification of FeP and FezP phases (Fig. 28.4a) and their relative contributions depending on the temperature and other experimental conditions in which the synthetic work is carried out [11,12]. 

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