title: Microwave-assisted hydrolysis of polysaccharides over polyoxometalate clusters.
abstract: Polyoxometalate (POM) clusters were utilized as recyclable acid catalysts and microwave-absorbing agents for the microwave-assisted hydrolysis of corn starch and crystalline cellulose. Phosphotungstic (PW) and silicotungstic (SiW) acids showed high hydrolyzing activity, while phosphomolybdic acid (PMo) showed lower glucose stability. The PW catalyst could be recycled by ether extraction at least 4 times without changing its catalytic activity. The addition of PW could reduce the energy demand required for running the hydrolysis by 17-23%. The dielectric property of the aqueous PW solution was important for increasing the microwave-absorption capability of the reaction system and reducing the energy consumption.
authors.affiliation: Oceanography Section, Science Research Center, Kochi University, Kochi, Japan. stsubaki@kochi-u.ac.jp
authors.forename: Shuntaro
authors.initials: S
authors.lastname: Tsubaki
authors.forename: Kiriyo
authors.initials: K
authors.lastname: Oono
authors.forename: Tadaharu
authors.initials: T
authors.lastname: Ueda
authors.forename: Ayumu
authors.initials: A
authors.lastname: Onda
authors.forename: Kazumichi
authors.initials: K
authors.lastname: Yanagisawa
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Mitani
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Azuma
mesh_terms: D000042:Absorption; D002482:Cellulose / Q000378:metabolism; D003460:Crystallization; D004553:Electric Conductivity; D006361:Heating; D006868:Hydrolysis / Q000187:drug effects; D008872:Microwaves; D010772:Phosphotungstic Acid / Q000494:pharmacology; D011134:Polysaccharides / Q000378:metabolism*; D059027:Recycling; D012996:Solutions; D013213:Starch / Q000378:metabolism; D013696:Temperature; D017973:Tungsten Compounds / Q000494:pharmacology*; D014867:Water / Q000494:pharmacology; D003313:Zea mays / Q000737:chemistry; D000099294:Polyoxometalates
chemical_list: D002482:Cellulose; D010772:Phosphotungstic Acid; D011134:Polysaccharides; D012996:Solutions; D013213:Starch; D017973:Tungsten Compounds; D014867:Water; C102296:polyoxometalate I; D000099294:Polyoxometalates
keywords: Corn starch; Crystalline cellulose; Dielectric property; Microwave-assisted hydrolysis; Polyoxometalate