ROCHA, Alysson Israel Oliveira.; GOMES, Josileido.; MENEZES, Romualdo Rodrigues.; NEVES, Gelmires de Araújo.; SANTANA, Lisiane Navarro de Lima.
Resumo:
Bentonite clays are aluminium–silicates that when heated turn into mullite. The sintering of mullite obtained
from these mineral clays by quick microwaves heating comes up as an alternative process for mullite
powders synthesis. The use of quick heating on ceramics nanopowders’ synthesis is a recent technology
that is being successfully used on synthesis with microwaves and synthesis process by combustion. The
quick microwaves heating enables adding heat quickly and equally, accelerating the nucleation kinetics and
the development of the mullite stage. Thus, the purpose of this work is to analyze the effect of the
microwaves heating process variables, analyzing the influence of the applied power and of the heating rate
on the mullite powders obtaining from bentonite clays. The clays have been favored and submitted to the
following characterizations: chemical granulometric and mineralogically. Subsequently, the clays have been
delamined aiming deagglomeration and separation of the thinner fractions and submitted to granulometri c
and mineralogical characterization. The synthesis has been realized on a domestic microwaves oven. The
obtained powders have been characterized by X-ray diffraction. The results showed that the applied power
variation and the sintering time are fundamental on the obtaining of mullite powders.
