Synthesis of Zeolitic Imidazolate Framework-8 Using Glycerol Carbonate

Glycerolcarbonate can be used as a green solvent for synthesizingzeolitic imidazole framework-8, which can be also recycled for severalcycles. In this study, we show that glycerol carbonate (GlyC),a bio-basedderivative of glycerol, can be used as a suitable green solvent forthe synthesis of metal-organic frameworks (MOFs). In particular,a zinc-based zeolitic imidazolate framework-8 (ZIF-8) was synthesizedby exploring several different experimental conditions (in terms oftemperature, reaction time, and reactants' concentrations)to find that the yield of the reaction and the quality of the products,measured in terms of crystallinity, surface area, and porosity, werein line with those obtained in the most commonly (non-green) usedsolvents. GlyC was also found to be reusable for several cycles, maintainingthe same original quality as a solvent for the synthesis. Finally,some indicators for the assessment of the greenness of a process (E-factorand PMI) revealed a milder environmental impact of GlyC with respectto other solvents.