Highly Selective Production of the Biobased Polymeric Monomer Tetrahydrofuran-2,5-dimethanol from 5-Hydroxymethylfurfural over the Ni@U-Silicalite-1 Catalyst

The upgrading and utilization of 5-hydroxymethylfurfural (HMF) as a platform chemical for the manufacture of biofuels and biopolymers have drawn a lot of attention, especially for the selective hydrogenation of HMF to the biobased polymeric monomer tetrahydrofuran-2,5-dimethanol (THFDM). However, the catalytic hydrogenation of HMF with sustainability remains challenging. Herein, we report the synthesis of the Ni@U-Silicalite-1 catalyst, which shows a satisfying selectivity to THFDM (95.6%) under mild reaction conditions (1.5 MPa H2 and 130 °C). Characterization results show that the U-Silicalite-1 zeolite has a short b-axis, a flat reaction surface, and enlarged mesopores, which facilitate the accessibility to active sites of HMF. Meanwhile, the high distribution and small size of Ni nanoparticles contribute to the excellent catalytic efficiency and recyclability. Moreover, the strong interaction between Ni species and U-Silicalite-1 zeolite prevents the aggregation and leaching of Ni nanoparticles and endows the Ni@U-Silicalite-1 catalyst with good stability.