title: Organic Carbonates: Efficient Extraction Solvents for the Synthesis of HMF in Aqueous Media with Cerium Phosphates as Catalysts.
abstract: We describe a process for the selective conversion of C6 -polyols into 5-hydroxymethylfurfural (5-HMF) in biphasic systems of organic carbonate/water (OC/W), with cerium(IV) phosphates as catalysts. Different reaction parameters such as the OC/W ratio, catalyst loading, reaction time, and temperature, were investigated for the dehydration of fructose. Under the best reaction conditions, a yield of 67.7 % with a selectivity of 93.2 % was achieved at 423 K after 6 h of reaction using [(Ce(PO4)1.5 (H2 O)(H3 O)0.5 (H2 O)0.5)] as the catalyst. A maximum yield of 70 % with the same selectivity was achieved after 12 h. At the end of the reaction, the catalyst was removed by centrifugation, the organic phase was separated from water and evaporated in vacuo (with solvent recovery), and solid 5-HMF was isolated (purity >99 %). The recovery and reuse of the catalyst and the relationship between the structure of the OC and the efficiency of the extraction are discussed. The OC/W system influences the lifetime of the catalysts positively compared to only water.
authors.affiliation: Department of Chemistry, University of Bari, Via Orabona n. 4, 70126, Bari, Italy. angela.dibenedetto@uniba.it.|CIRCC, Via Celso Ulpiani n. 27, 70126, Bari, Italy. angela.dibenedetto@uniba.it.
authors.forename: Angela
authors.initials: A
authors.lastname: Dibenedetto
authors.affiliation: CIRCC, Via Celso Ulpiani n. 27, 70126, Bari, Italy.|Department of Chemical and Biomolecular Engineering, NUS, 4 Engineering Drive 4, Singapore, 117585, Singapore.
authors.forename: Michele
authors.initials: M
authors.lastname: Aresta
authors.affiliation: CIRCC, Via Celso Ulpiani n. 27, 70126, Bari, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: di Bitonto
authors.affiliation: CIRCC, Via Celso Ulpiani n. 27, 70126, Bari, Italy.|Water Research Institute (IRSA-CNR), National Research Council, Via de Blasio 5, 70132, Bari, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Pastore
mesh_terms: D002384:Catalysis; D002563:Cerium / Q000737:chemistry*; D003890:Desiccation; D005561:Formates / Q000737:chemistry*; D005632:Fructose / Q000737:chemistry*; D005662:Furaldehyde / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D059625:Liquid-Liquid Extraction; D015394:Molecular Structure; D010710:Phosphates / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D005561:Formates; D010710:Phosphates; D012997:Solvents; D014867:Water; D005632:Fructose; D002563:Cerium; C008046:5-hydroxymethylfurfural; D005662:Furaldehyde; C023025:methyl carbonate; C048083:cerium phosphate
keywords: biphasic catalysis; carbohydrates; cerium; solvent effects; structure-activity relationships