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The suitability of the charcoal obtained from woody biomass pyrolysis in a continuous screw reactor at 573, 773, 973, 1173 K temperature profile as fuel and reducing agent in metallurgical applications has been evaluated, in order to reduce the CO2 emissions in these processes. On the one hand, a comparative study between charcoal and commercial reducers has been carried out. On the other hand, different proportions of this charcoal have been added to an industrial coking coal blend and carbonized together in a semi-pilot movable wall oven, to study the influence in the plastic and mechanical properties of the produced biocoke. The charcoal obtained fulfills the requirements to be used as fuel and reducer in non-ferrous processes where no mechanical strength is required, like rotary kilns, in substitution of fossil reducers. Its higher heating value (>32 MJ kg−1) is in the range or over those of fossil coals, with the advantage of not containing polluting elements (S, N) and having less ash. The addition of up to 0.9 wt.% almost does not affect the quality of the biocoke; but the addition of ³2 wt.% degrades the biocoke mechanical and plastic properties below the demanded requirements. Moreover, biocoke reactivity seems independent of the amount of charcoal added.

Recycling carbon fiber from residual carbon fiber reinforced plastics (CFRP) is one of the key aspects of the future in the field of waste management. This work presents the possibility of recovering chemical compounds through the thermo-catalytic treatment of the gases and vapors produced from the decomposition of the polymeric resin that takes place in the recycling of CFRP by pyrolysis. A lab-scale installation consisting of two reactors placed in series has been used for the experiments. In the first reactor, pyrolysis of poly(benzoxazine)-based composite waste has been carried out at 500 °C. In the second reactor, the thermo-catalytic treatment of gases and vapors has been performed at 900 °C in the presence of a commercial and a lab-prepared reforming catalyst. The thermal treatment of gases and vapors leads to a significant reduction in the collected liquids and a H2-rich gas fraction. When reforming catalysts are used, the organic fraction of the liquids is virtually eliminated and gas fractions containing more than 50% H2 in volume are generated. The results obtained show that it is possible to valorize the material content of the polymer resin, which represents an important advance in the recycling of CFRP by pyrolysis.

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