Synthesis of porous magnesium oxide by thermal decomposition of basic magnesium carbonate

Abstract

On calcination of basic magnesium carbonate at 20-800°C, an induction period was observed in the initial stage of thermal decomposition. At the decomposition degree higher than 20% of the weight loss, the specific surface area varied in proportion with the decomposition degree, which points to equal rates of gas liberation and recrystallization of intermediate products into an active oxide. The individual phase of magnesium oxide alone is identified at the minimal temperature of 500°C. As the calcination temperature and time increase, the MgO phase is structured further, which decreases in its specific surface area and basicity.