Tuning acid and basic features on MgxAlOy-SiO2 impacted ethanol upgrading to 1,3-butadiene

Abstract

Ethanol has captured a lot of interest from the industry in recent years due to its sustainable appeal, being obtained through the process of biomass fermentation. Not only its application in the energy sector as a potent fuel, but its conversion to higher added value products has been a commercial highlight. In this work, we sought to synthesize a new mixed catalyst Mg_xAlO_y-SiO₂ to investigate its performance in the upgrading of ethanol to a product of significant relevance, particularly for the plastics and polymers industry, namely1,3-butadiene. The molar ratio of Mg:Al:Si in the catalyst was tuned, revealing a remarkable impact on the selectivity of the reaction products. For the production of 1,3-butadiene, the optimal catalyst composition was determined to be 3:1:1, exhibiting a selectivity of 23 % at 723 K. This composition offered a favorable amount of acid and basic active sites, indicated by the acid to basic sites density ratio of 0.109, with medium basic sites predominantly represented. This arrangement is believed to have facilitated dehydrogenation, condensation, and dehydration reactions, each playing a crucial role in the overall process.