Hierarchical CoOx/TS-1 Catalyst Derived from Sequential Acid-Alkali Treatment for Efficient Selective Oxidation of Ethylbenzene to Acetophenone
摘要
This study addresses the limitations of conventional industrial methods for acetophenone (AP) production by developing a modified TS-1 zeolite catalyst with a predominantly interparticle micro-mesoporous architecture for the selective oxidation of ethylbenzene (EB) under mild and environmentally benign conditions. To overcome the intrinsic pore constraints of TS-1 zeolite that restrict substrate accessibility and mass transfer, a specific sequential acid-then-alkali post-treatment strategy followed by cobalt oxide impregnation was employed. This treatment sequence leads to surface enrichment of framework-like Ti species and the creation of interparticle mesoporosity, resulting in a coexisting micro-mesoporous architecture while preserving the MFI framework. Under optimized reaction conditions, the catalyst achieved 76.2% EB conversion and 74.8% AP selectivity to AP. Systematic evaluation in the EB/H2O2 oxidation system under acidic reaction conditions revealed a synergistic effect between framework titanium active sites and cobalt oxide active species. The developed catalyst offers distinct advantages, including straightforward synthesis procedure, high catalytic activity, and facile recoverability.
Graphical AbstractThis study constructs a micro-mesoporous TS-1 via specific sequential acid-then-alkali modification and loads optimal Co3O4 to create dual active centers. This architecture reduces mass transfer resistance and optimizes active sites, enabling efficient ethylbenzene oxidation to acetophenone under mild conditions. The catalyst is easily recoverable, regenerable, and stable.