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9Three different bimetallic Ru:Ni catalysts supported on a mesoporous silica MCM-48 10 were prepared by consecutive wet impregnations, with a total metal loading of ca. 3 % 11(w·w -1 ). Ru:Ni ratios spanned in the range of 0.15 -1.39 (w·w -1 ) and were compared with

The extraction/hydrolysis process of arabinoxylans from destarched wheat bran was studied in this work using different mesoporous silica supports and the corresponding RuCl3-based catalysts. The effects of temperature, time, catalyst supports and ruthenium catalysts were investigated and discussed in terms of the arabinoxylans extraction yield and their polymerization degree. Relatively high temperatures (180 ºC), short extraction times (10 minutes) and RuCl3 supported on Al-MCM-48 led to a high amount of arabinoxylans extracted (78%) with a low molecular weight (9 KDa). Finally, a relation between the operating conditions, the arabinoxylans extraction yield and the molecular weight was stablished based on the obtained results. Abbreviation: AXs, arabinoxylans; DWB, destarched wheat branKeywords: Hemicelluloses fractionation, wheat bran, arabinoxylans, heterogeneous catalysis, hydrothermal process, biomass Chemical compounds studied in this articleXylose (PubChem CID: 135191); Arabinose (PubChem CID: 439195) Highlights:-Effects of ruthenium catalyst, temperature, time and catalyst support are discussed -RuCl3-based catalysts show good activity for the arabinoxylans extraction from wheat bran -Liquid extracts are characterized in terms of sugars, molecular weight and purity

Supercritical water hydrolysis is an effective pretreatment for hexitol synthesis over Ru/MCM-48.

Highlights 1. Crystalline cellulose is hydrolyzed into glucose with a yield of 63.8% 2. The Ag(I) ions exchanged allowed the hydrolysis of cellulose 3. The incorporation of silver produces a redistribution of acid sites 4. Al(III) species which are octahedrically coordinated were detected