MnCo2O4 spinel supported ruthenium catalyst for air-oxidation of HMF to FDCA under aqueous phase and base-free conditionsElectronic supplementary information (ESI) available: Catalyst preparation, characterization - figures (NH3-TPD, TEM, TEM-EDS, XPS, and XRD) and tables (EDS, BET, CO chemisorption, and ICP-AES), & FDCA purification - 1H- and 13C-NMR of purified FDCA. See DOI: 10.1039/c7gc00027h

A new class of MnCo 2 O 4 spinel supported Ru catalyst, Ru/MnCo 2 O 4 , was exploited to afford the highest yield of FDCA (99.1%) from base-free air-oxidation of HMF in water. The catalyst Ru/MnCo 2 O 4 having both Lewis and Brønsted acidic active sites greatly enhanced the FDCA yield. The catalyst was recyclable up to five successive runs without considerable loss of its original activity. A new class of MnCo 2 O 4 spinel supported Ru catalyst, Ru/MnCo 2 O 4 , was exploited to afford the highest yield of FDCA (99.1%) from base-free air-oxidation of HMF in water.