Rapid room temperature synthesis of tin-based mesoporous solids: Influence of the particle size on the production of ethyl lactate

Abstract

A series of tin-based mesoporous catalysts was prepared via a novel straightforward sol-gel procedure leading to an extremely short synthesis time decreased up to 5 min at room temperature. This synthesis, together with the precise control of the selected particle size, represents an advancement compared to the state of the art and can be easily applied to large scale production. Characterization of the materials revealed the presence of MCM-41 like architecture with a high specific surface area, narrow pore size distribution, insertion of tin in tetrahedral coordination and a good balance of Lewis/Brønsted acidity. Moreover, all these characteristics were almost identical for the entire series thus making these solids an ideal case study to investigate the influence of the particle size on the catalytic behavior. The Sn-containing materials were tested as catalysts in the conversion of dihydroxyacetone into ethyl lactate. The excellent correlation between particle size and catalytic performances proves the importance of size control. In addition, the absence of leaching was proved via hot filtration experiments and the materials preserved their activity in multiple catalytic cycles.