Hydrogenation of 5-Hydroxymethylfurfural to 2,5-Furandimethanol over the Magnetic Nanostructured RuMoO _<i>x</i> /Fe ₃ O ₄ Catalyst

2,5-Furandimethanol (FDM) is a diol compound with significant application potential and can be efficiently synthesized via the hydrogenation of 5-hydroxymethylfurfural (HMF). Due to HMF’s susceptibility to side reactions and the high costs of product separation, a one-step transformation of high-concentration HMF to FDM is highly desirable. In this study, easily separable magnetic RuMoOx/Fe3O4 nanoparticles are synthesized via chemical reduction and exhibit high catalytic performance in the hydrogenation of high-concentration HMF (17 wt %) to FDM. The analytical results indicate that the active metals are uniformly dispersed on the Fe3O4 surface and that an optimal Ru/Mo ratio (1:3.82) significantly enhances HMF conversion and FDM selectivity. Under the optimized reaction conditions (4 MPa H2, 90 °C, and 6 h), the HMF conversion reaches 98.65%, with FDM selectivity as high as 96.46%. Notably, even after seven consecutive catalytic cycles, the FDM yield remains above 83%.