Organic precursor synthesis of Al–Mg mixed oxides and hydrotalcites

Mixed Al–Mg oxides have been synthesized using three different methods: thermal decomposition of Al–Mg nitrate mixture in presence of citric acid, Al- and Mg-formates, and usual co-precipitation. These methods give oxide samples with similar crystal structures, but with different pore size distributions. The transformation of mixed Al–Mg oxides into hydrotalcite layered structure as result of their hydration with ultrasonic treatment was studied. The prepared Al–Mg oxides and hydrotalcite are characterized by the same basicity (H− ⩽ +17.2) and activity in MBOH decomposition test reaction.