Ru-Containing Magnetically Recoverable Catalysts: A Sustainable Pathway from Cellulose to Ethylene and Propylene Glycols

Abstract

Biomass processing to value-added chemicals and biofuels received considerable attention due to the renewable nature of the precursors. Here, we report the development of Ru-containing magnetically recoverable catalysts for cellulose hydrogenolysis to low alcohols, ethylene glycol (EG) and propylene glycol (PG). The catalysts are synthesized by incorporation of magnetite nanoparticles (NPs) in mesoporous silica pores followed by formation of 2 nm Ru NPs. The latter are obtained by thermal decomposition of ruthenium acetylacetonate in the pores. The catalysts showed excellent activities and selectivities at 100% cellulose conversion, exceeding those for the commercial Ru/C. High selectivities as well as activities are attributed to the influence of Fe3O4 on the Ru(0)/Ru(4+) NPs. A facile synthetic protocol, easy magnetic separation, and stability of the catalyst performance after magnetic recovery make these catalysts promising for industrial applications.

Functionalised heterogeneous catalysts for sustainable biomass valorisation

“…Biomass-derived polyols, such as ethylene glycol and propylene glycol are important building blocks for the production of liquid fuels, emulsifiers, surfactants, and pharmaceuticals. 371 A promising pathway to produce these polyols is cascade hydrogenolysis of cellulose over magnetic catalysts. In view of this, Manaenkov et al 371 developed finely dispersed Ru NPs (average particle size of 2 nm) on Fe 3 O 4 -SiO 2 with various Ru nominal loadings of 1, 3, and 5 wt% for the one-pot hydrogenolysis of cellulose in subcritical water.…”

“…371 A promising pathway to produce these polyols is cascade hydrogenolysis of cellulose over magnetic catalysts. In view of this, Manaenkov et al 371 developed finely dispersed Ru NPs (average particle size of 2 nm) on Fe 3 O 4 -SiO 2 with various Ru nominal loadings of 1, 3, and 5 wt% for the one-pot hydrogenolysis of cellulose in subcritical water. The developed catalysts (especially 5 wt% Ru loaded catalyst) showed good cellulose conversions and product selectivities, hereby outperforming a commercial Ru/C catalyst, ascribed to the constructive effect of Fe 3 O 4 on the redox couple of Ru 0 /Ru 4+ .…”

Hydrogenation of bio-oil into higher alcohols over Ru/Fe3O4-SiO2 catalysts

“…In this respect, magnetic recovery of the catalysts seems particularly promising [33]. Magnetic catalyst recovery generates more environmentally friendly processes, cheaper products, and conserved energy for a range of processes [34][35][36][37]. In the majority of cases, catalytic complexes or nanoparticles (NPs) are placed on the surface of magnetic NPs [33,38,39], but for efficient magnetic separation, the NP aggregation is required [40,41].…”

Hydrothermal Stability of Ru/SiO2–C: A Promising Catalyst for Biomass Processing through Liquid-Phase Reactions

“…The dehydrogenation (that produces ketone), in absence of metals, is catalyzed by acid and basic sites through a concerted mechanism and serves as a basicity measure of materials analyzed. Table 3 shows the results of the catalytic decomposition reaction of isopropanol for SiO 2 …”

“…The results offered proof that the addition of Fe 3 O 4 to the mesoporous SiO 2 promotes the hydrogenolysis reaction. When the ruthenium nanoparticles are deposited on Fe 3 O 4 , there is an interaction and transference of electrons from the surface of Fe 3 O 4 to the ruthenium that facilitates hydrogenolysis, and this is reflected in higher catalytic activity and selectivity [2].…”