Magnetically Recoverable Bifunctional Catalysts for the Conversion of Cellulose to 1,2-Propylene Glycol

Abstract

The use of cellulose instead of oil to produce 1,2-propylene glycol (1,2-PG) is of great significance for building a sustainable world. Herein, we synthesize Fe3O4@SiO2/Ru-WO x core–shell magnetically recoverable catalysts containing both Lewis acid and metal active sites using well-shaped Fe3O4@SiO2 core–shell magnetic nanospheres as the substrate. We investigated the catalytic performances of the bimetallic catalysts with various metals as well as different metal contents and WO x loadings for the conversion of cellulose to 1,2-PG. The results showed that Fe3O4@SiO2/10%Ru-20%WO x was more favorable for 1,2-PG production, with a 1,2-PG selectivity of 32.4% and a cellulose conversion of 96.8%. Our characterization and activity tests suggested that WO x on the Fe3O4@SiO2 nanospheres produced abundant Lewis acid sites to effectively promote glucose isomerization to fructose before glucose undergoes the retro-aldol condensation reaction. Moreover, the Ru further hydrogenated the C3 intermediate to 1,2-PG. It was notable that the catalyst can be separated through a simple magnetic separation after the end of the reaction, and it still maintained high catalytic activity after 5 uses.

Unidimensional Approximation of the Diffuse Electrical Layer in the Inner Volume of Solid Electrolyte Grains in the Absence of Background Ions

“…E.g., attraction of protonated cellulose to the catalyst surface is theorized to play an important role in its hydrolysis over solid acids. [20] Attraction of the substrate is particularly important for bifunctional catalysis where some of the catalytic sites are unconditionally surface-bound (e. g., the metal in metalaugmented solid acids for combined hydrolysis and hydrogenation of polysachharides [60][61][62][63] ). Another possibility is preferential orientation of polar molecules in the electric field of EDLs.…”

Recyclable Cu Salt-Derived Brønsted Acids for Hydrolytic Hydrogenation of Cellulose on Ru Catalyst

“…Cellulose is the most abundant, non-edible biomass on earth, and represents a reliable carbon-neutral resource for sustainable production of bio-fuels and chemicals. [1][2][3][4][5][6] To this end, as a linear homopolysaccharide of Dglucose units linked by β-1,4-glycosidic bonds, cellulose can be efficiently converted via a hydrolytic hydrogenation route, involving its hydrolysis to glucose and subsequent glucose hydrogenation, to a wide range of products, exemplified by sorbitol, [7][8][9][10][11][12] ethylene glycol, [13][14][15][16][17] propylene glycol [18][19][20][21] , ethanol [22][23][24] and isosorbide. 25,26 The hydrolytic hydrogenation route of cellulose is limited by its hydrolysis, which is conventionally catalyzed by mineral acids, such as H 3 PO 4 and H 2 SO 4 .…”

Synthesis of Novel Azo-Linked 5-Amino-Pyrazole-4-Carbonitrile Derivatives Using Tannic Acid–Functionalized Silica-Coated Fe3O4 Nanoparticles as a Novel, Green, and Magnetically Separable Catalyst

“…Compared to other nanoparticles, magnetite (Fe 3 O 4 ), due to its unique magnetic properties ( Xin et al, 2020 ), easy magnetic separation ( Hamedi et al, 2018 ), low toxicity ( Zhao et al, 2014 ), environmental compatibility ( Eslahi et al, 2021 ), and chemically modifiable surface ( Bai et al, 2013 ), has attracted scientists. Therefore, applications of these magnetic nanoparticles (MNPs) have been developed in drug delivery, cancer treatment, magnetic resonance imaging, tissue repairing, contrast agents, magnetic storage media, biosensing, magnetic inks for jet printing, and catalysis ( Inaloo et al, 2020 ; Eslahi et al, 2021 ).…”