Unraveling support effects in Ru-based catalysts for efficient conversion of marine biomass to sugar alcohols

The valorization of marine biomass into high-value chemicals presents both ecological and economic opportunities. This work systematically investigated support-dependent catalytic behavior in ruthenium-based systems for converting Enteromorpha prolifera into sugar alcohols (rhamnitol, sorbitol and xylitol). Through comparative analysis of self-synthesized Ru/TS-1 with Ru/SiO 2 , Ru/TiO 2 and commercial Ru catalysts (Ru/C and Ru/Al 2 O 3 ), we demonstrated that TS-1 supported catalyst exhibit superior performance through three synergistic mechanisms: (1) enhanced metal-support interactions (MSI) yielding optimal Ru 3 + /Ru 0 balance (XPS quantification), (2) maximized metallic surface area (78.3 m²/g) with minimum Ru particle size, and (3) tailored acid-base bifunctionality (NH 3 /CO 2 -TPD characterization). The optimized Ru/TS-1 achieved exceptional sugar alcohol yields (90–95%, productivity=19.1 mol rhamnitol mol Ru − 1 h −1 ) with favorable kinetics (TOF=425.8 h −1 , E a =21.8 kJ·mol −1 ). Combined experimental and density functional theory (DFT) analyses revealed that moderate acidity/basicity facilitated ring-opening of cyclic rhamnose while preventing excessive cleavage of C3-C4 bond (responsible for acetol formation). Mechanistic studies identified Ru 3+ sites as critical for substrate adsorption and Ru 0 domains for H 2 activation. This fundamental understanding of support effects provides a rational design strategy for developing advanced catalysts in marine biomass upgrading. • Ru/TS-1 exhibited outstanding efficiency for sugar alcohols production from E. prolifera . • As high as ∼94 % yield of rhamnitol was achieved in high concentration of substrate. • The key factors of metal and support on the catalytic activity of catalyst were disclosed. • Ru 0 , Ru 3+ and TS-1 cooperative contributed to sugar alcohols production.