Síntese de alumina utilizando ativação química e energia térmica.

Abstract

In the face of great technological importance of alumina, this research aimed to develop a process of synthesis of alpha alumina using chemical activation and thermal energy. This study used as the precursor aluminum acetate, aluminum chloride, aluminum nitrate and aluminum sulfate, which were treated and subjected to chemical activation, varying concentration and duration of exposure to nitric acid solution. The synthesized materials were subjected to conventional furnace annealing, rapid firing cycles and energy microwave then were characterized by differential thermal analysis (DTA) and gravimetric (TGA), X-ray diffraction (XRD) and surface area (SA) . The results showed that the best precursor was aluminum nitrate, which showed for the post activated chemically and calcined in a conventional oven at 1000°C materials consisting of alpha alumina, with specific areas ranging from 4 to 16m2 / g with pore diameters from 213 to 336 nm. The materials synthesized by microwave showed specific areas ranging from 3 to 15m2 / g with pore diameters between 190 to 485 nm. For materials subject to rapid firing cycles, it was found that there was no influence of chemical activation used, since the powders synthesized showed basically consisting of alpha alumina.