CO2 Adsorption on Modified Mg-Al-Layered Double Hydroxides

Because of increases in the burning of fossil fuels, there is an increased emission of pollutant gases (e.g. CO2) into the atmosphere. An alternative to minimize these emissions is to capture these gases using porous materials, such as layered double hydroxides (LDHs). In this study, LDHs were synthesized by co-precipitation of ion salts of Mg2+ and Al3+. After the synthesis, the materials were treated with a template to expand the layers. The samples were then characterized by X-ray diffraction, thermogravimetric analysis/derivative thermogravimetry, adsorption/desorption of nitrogen, scanning electron microscopy/energy-dispersive X-ray spectroscopy and transmission electron microscopy. A CO2 adsorption study was then performed to determine the adsorption capacity of the material in accordance with the contact time between the gas and the adsorbent. The adsorption capacities of LDHs and LDHs-P123 for CO2 were 0.72 and 1.36 mmol/g, respectively, showing satisfactory results post-treatment.