One-pot conversion of cellobiose to mannose using a hybrid phosphotungstic acid–cerium oxide catalyst

Abstract

A hybrid catalyst composed of phosphotungstic acid coated cerium oxide nanoparticles was demonstrated to catalyze the one-pot conversion of cellobiose, the disaccharide unit of cellulose, to a monosaccharide mixture of glucose and mannose. A high % conversion of cellobiose (up to 99%) was achieved resulting in a yield of mannose up to 15.8%. The yield of mannose from a glucose starting material was 22.8%, exceeding those of previous ceriumbased glucose epimerization catalysts. The components of the hybrid material were revealed to function synergistically via a two-step process. Cellobiose was hypothesized to be first hydrolyzed to glucose, which was subsequently epimerized to mannose by the cerium ions leached from the catalyst. The 13 C NMR spectroscopic study suggested that the epimerization likely occurred by the way of a 1,2-carbon shift reaction mechanism.

Kinetic and mechanistic investigations of the direct synthesis of dimethyl carbonate from carbon dioxide over ceria nanorod catalysts

“…The methanol and DMC content of our reaction products were analyzed using a high performance liquid chromatography (HPLC) method developed by the National Renewable Energy Laboratory [23,24]. Briefly, 10 lL of filtered analyte was injected into the HPLC instrument (Waters, Milford, MA).…”

Microgel-Catalyzed Hydrolysis of Nonactivated Disaccharides

“…Nonenzymatic methods to hydrolyze cellulose into monosaccharides often involve in the pretreatment steps, the use of acid catalysts, subcritical − and supercritical fluids, − and ionic liquids. − However, the general use of these catalysts remains hampered by low activity and/or selectivity, or by the production of various side products due to the applied harsh reaction conditions . The development of enzyme mimics is another attractive nonenzymatic way to hydrolyze glycosidic bonds of nonactivated saccharide.…”

“…10−12 However, the general use of these catalysts remains hampered by low activity and/or selectivity, 13 or by the production of various side products due to the applied harsh reaction conditions. 14 The development of enzyme mimics is another attractive nonenzymatic way to hydrolyze glycosidic bonds of nonactivated saccharide. Very recently, functional La(III) metallomicelles 13 and histidine-derivatized 15 micelles have been reported to hydrolyze β-glycosidic bonds in alkaline aqueous solution between 80 and 100 °C.…”

Nano Ru catalysts supported on carbon nanotubes for cellobiose conversion to sugar alcohols: effects of CNT channel size

“…Therefore, studies on catalytic conversion of cellobiose are important for the basic understanding of catalyst requirements for the efficient utilization of cellulose. [7][8][9] Supported ruthenium (Ru) catalysts are well known as efficient catalysts for a wide range of hydrogenation reactions, 10 including the hydrogenation of cellobiose. [9][10][11][12] The catalytic support plays an important role in many reaction processes, determining the catalyst structure and catalytic performance.…”