Monosodium glutamate-mediated hierarchical porous formation in LTA zeolite to enhance CO2 adsorption performance

This study evaluated the CO2 adsorption capacity of microporous and hierarchical LTA zeolites at different temperatures (10, 20, 30, 40, and 50 °C) and atmospheric pressure. Monosodium glutamate was employed as a mesoporosity agent, which unlike other mesopore-generating templates such as surfactants or polymers, can be easily removed by washing with water, eliminating the calcination step. The samples were characterized by X-ray diffraction, thermal analyzes, temperature-programmed desorption of CO2, adsorption-desorption of nitrogen, infrared spectroscopy by Fourier transform and scanning electron microscopy. In both syntheses, the crystalline structure of the LTA zeolite was obtained. The sample synthesized with monosodium glutamate (LTA-Glut) showed a bimodal pore system (micro-mesopores), which favored the increase in CO2 adsorption capacity, improving the diffusional effect and stability in several CO2 adsorption-desorption cycles compared to the microporous LTA zeolite (LTA-Conv).