Gold catalyst recycling study in base-free glucose oxidation reaction

This work is devoted to the study of viability of immobilized gold colloids on carbon as catalysts for the base-free glucose oxidation reaction with a special emphasis made on catalysts' recycling, operational life and possible routes for deactivation/reactivation under batch conditions. The observed catalytic behavior is related to all possible manners of deactivation, like gold metal state changes (particle size agglomeration or leaching), support modifications or active sites blocking by intermediates. In an attempt to recover the initial catalytic activity, the samples are subjected to different treatments such as H2O and NaOH washings and calcination. The failure of the regeneration procedures to recover the initial activity and after detailed catalyst' characterization allows us to find out the main cause of deactivation. (C) 2017 Elsevier B.V. All rights reserved.