Catalytic activity of Co-Mg mixed oxides in the VOC oxidation: Effects of ultrasonic assisted in the synthesis

Ultrasound effect in the synthesis of catalysts of cobalt oxides prepared starting from the coprecipitation method of a hydrotalcite structure was evaluated in this work and characterized by DRX, FRX, BET, TPR and TPO. It is found that catalytic conversion of butanol on the Co-Mg-Al mixed oxides prepared by ultrasound method (10 min) is higher than that on the Co-Mg-Al mixed oxides prepared by conventional treatment (24 h). The surface area and the butanol oxidation are linearly related to the content of the hydrotalcite-like phase in the precursor, which resulted in highly dispersed Co (Co²⁺), MgO and A1₂O₃ particles in the final catalyst. Similarly, the use of ultrasound in the synthesis reveals a benefic effect in so far as similar solids are obtained in much less time. The catalysts show greater activity and selectivity to CO₂ and H₂O than the commercial ones.