Hierarchical fluoride-containing zeolite Y supported Ru for catalytic conversion of xylose to xylitol.

Hierarchical fluoride-containing zeolite HY (Hie-HY(F)) is an interesting material because it tunes both a high mesoporosity and a moderate acid property, which could benefit the transformation of xylose to xylitol. Herein, we synthesized a new Hie-HY(F) by etching NH 4 Y with ammonium fluoride (NH 4 F) under ultrasonication at 60 °C for 20, 40, and 60 min. After etching with NH 4 F solution, the Hie-HY(F)s contained fluoride in the zeolite frameworks with high mesoporosity and moderate acid properties. The sonication time longer than 20 min caused the structure to collapse rather than the creation of mesoporosity. The Hie-HY(F)s were further used as supports for the Ru catalyst. When loaded with Ru precursor and calcined in air, RuO 2 phase was formed in all catalysts. The RuO 2 supported on Hie-HY(F)s had a lower reduction temperature than that on HY. Ru supported on Hie-HY(F)-20 gave the reactivity of xylose conversion to xylitol, the highest yield of 80.1 %, providing the reusability up to four cycles. [Display omitted] • Synthesis of hierarchical fluoride-containing zeolite Y (Hie-HY(F)s) was disclosed. • Hie-HY(F)s was done by etching in NH 4 F solution under sonication at various times. • Dealumination and fluorination played a crucial role in mesoporosity and acidity. • Hie-HY(F)s was used as a novel support for Ru in xylose conversion to xylitol. • Ru/Hie-HY(F)-20 gave the highest xylitol productivity, 80.1 % yield. [ABSTRACT FROM AUTHOR]