Chemically treated eggshell wastes as a heterogeneous and eco-friendly catalyst for oximes preparation

The synthesis of oximes from aldehydes and ketones was successfully carried out in ethanol under refluxing conditions using the Chemically Treated Eggshell (CTE) waste and its analog Chemically Treated then Calcined waste at 800 °C (CTEC800) as eco-friendly catalysts. After preparation and characterization of these catalysts by several methods including TGA/TDA, X-ray diffraction, SEM, EDX, and FTIR, they gave satisfactory results. These results show that 100 mg was found as optimum quantity for oximes synthesis. This amount can lead to the corresponding oximes in good yields (60% and 69% using CTE and CTEC800 respectively) to excellent yields (87% and 96% using CTE and CTEC800 respectively). The remarkable features of this new approach are very good yields, short reaction times, and mild conditions. Catalytic activities and the ability to reuse up to 7 times are demonstrated.