title: Transformation of cellulose and its derived carbohydrates into formic and lactic acids catalyzed by vanadyl cations.
abstract: The transformation of cellulose or cellulose-derived carbohydrates into platform chemicals is the key to establish biomass-based sustainable chemical processes. The systems able to catalyze the conversion of cellulose into key chemicals in water without the consumption of hydrogen are limited. We report that simple vanadyl (VO(2+)) cations catalyze the conversions of cellulose and its monomer, glucose, into lactic acid and formic acid in water. We have discovered an interesting shift of the major product from formic acid to lactic acid on switching the reaction atmosphere from oxygen to nitrogen. Our studies suggest that VO(2+) catalyzes the isomerization of glucose to fructose, the retro-aldol fragmentation of fructose to two trioses, and the isomerization of trioses, which leads to the formation of lactic acid under anaerobic conditions. The oxidative cleavage of C-C bonds in the intermediates caused by the redox conversion of VO2(+)/VO(2+) under aerobic conditions results in formic acid and CO2. We demonstrate that the addition of an alcohol suppresses the formation of CO2 and enhances the formic acid yield significantly to 70-75 %.
authors.affiliation: State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (PR China).
authors.forename: Zhenchen
authors.initials: Z
authors.lastname: Tang
authors.forename: Weiping
authors.initials: W
authors.lastname: Deng
authors.forename: Yanliang
authors.initials: Y
authors.lastname: Wang
authors.forename: Enze
authors.initials: E
authors.lastname: Zhu
authors.forename: Xiaoyue
authors.initials: X
authors.lastname: Wan
authors.forename: Qinghong
authors.initials: Q
authors.lastname: Zhang
authors.forename: Ye
authors.initials: Y
authors.lastname: Wang
mesh_terms: D002384:Catalysis; D002482:Cellulose / Q000737:chemistry*; D005561:Formates / Q000737:chemistry*; D005947:Glucose / Q000737:chemistry; D019344:Lactic Acid / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D017968:Vanadium Compounds / Q000737:chemistry*
chemical_list: D005561:Formates; D017968:Vanadium Compounds; C030544:formic acid; D019344:Lactic Acid; C034028:vanadyl sulfate; D002482:Cellulose; D005947:Glucose; D010100:Oxygen
keywords: biomass; carbohydrates; homogeneous catalysis; reaction mechanisms; vanadium