Alkali etching-free synthesis of hierarchical Zr-BEA zeolite as a robust catalyst for the efficient production of lactic acid from carbohydrates

Abstract

Constructing hierarchical Zr-BEA zeolites via an alkali etching-free route is still of challenge. Here, we have prepared a hierarchical HR-Zr-BEA from a mesoporous Al-BEA which can be facilely synthesized using commercial chemicals as the structure-directing agent. The structure of HR-Zr-BEA was systematically characterized by XPS, XRD, DRIFTS, and UV–Vis DRS, and its acidic properties was tested by NH3-TPD and pyridine-adsorbed DRIFTS. We found that the hierarchical structure of HR-Zr-BEA could expose more amount of acid sites and then promote the selective conversion of xylose to the active intermediates, resulting in a higher yield of lactic acid (LaA) from xylose. Besides, HR-Zr-BEA also exhibited excellent reusability and substrate-generality.