Facile synthesis of amine-functionalized MIL-53(Al) by ultrasound microwave method and application for CO2 capture

An amine functional MIL-53(Al) material was prepared through a clean, rapid, energy-efficient method of microwave and ultrasound irradiation. The pure phase NH2-MIL-53(Al) can be formed in 25 min, utilizing the synergistic effect of microwave and ultrasound irradiation. The dramatic acceleration in reaction rates suggested that the removal of a passivation coating on the substrate particles and the resultant enhancement in mass and heat transfer. The porous MOFs exhibited a high thermal and chemical stability, decomposing at temperatures above 410 °C in air. The NH2-MIL-53(Al) performed an excellent adsorption for CO2. The CO2 capacities up to 33.86 cm3 g−1 at 298 K at low pressures, which suggests chemisorption between CO2 and pendan amine groups. Measurement of CO2 adsorption cycles proved that the functionalized materials show good regenerability and stability.