Catalytic synthesis of renewable 2-methylfuran from furfural†

Abstract

Biomass energy stands at the forefront of remedial strategies for the current energy deficit and has garnered considerable attention. The deployment of highly efficient catalysts is pivotal to the success of this energy form. Prevailing literature established that high-valent metal presence contributed significantly to the hydrogenation of furfural to prepare 2-methylfuran. In this study, we elucidated the efficacy of a monometallic catalyst consisting solely of cobalt and its oxides, denoted as Co/CoO_x, in the catalytic transformation of furfural derived from lignocellulosic biomass into 2-methylfuran. Leveraging the economical Co/CoO_x catalyst, in conjunction with minimal addition of hydroquinone, we accomplished the selective hydrodeoxygenation of furfural, culminating in an augmented yield of 2-MF up to 73%. This investigation is the inaugural confirmation that minuscule quantities of hydroquinone can efficaciously mitigate side reactions such as the polymerization of furfural within the selective hydrodeoxygenation process. The Co/CoO_x catalyst was characterized through an array of analytical techniques, including XRD, H₂-TPR and N₂-adsorption. These characterization studies unveiled that the optimal selectivity for 2-methylfuran was achieved when the ratio of Co⁰ : Co²⁺ in the catalyst approached approximately 95%.