Understanding Ta as an Efficient Promoter of MgO-SiO2 Catalyst for Conversion of the Ethanol-Acetaldehyde Mixture into 1,3-Butadiene

In this work, Ta was firstly reported as an efficient promoter of MgO-SiO2 for the conversion of ethanol and acetaldehyde to 1,3-butadiene. The doping of Ta into MgO-SiO2 forms Ta-O-Si bonds and generates more strong Lewis acid sites, which not only promote the aldol condensation reaction but also significantly facilitate the Meerwein-Ponndorf-Verley reduction, the total conversion around 80% which drops to 65% after 24 h. In addition, the catalyst showed desirable stability in 24 h long-term stability evaluation, the selectivity remained stable at 80%. Graphic Abstract