Amine‐modified acid‐activated attapulgite as efficient and stable adsorbents for CO2 capture from flue gas

Abstract

AbstractBACKGROUNDFossil fuel power plants are the primary contributors to carbon dioxide (CO2) emissions, necessitating effective and stable methods for adsorbing CO2 from flue gas under diverse conditions. Achieving this remains challenging due to the complexity of flue gas compositions and the prolonged operation of adsorption processes.RESULTSThis study focuses on enhancing CO2 adsorption in flue gas using attapulgite (ATP), activated by acid and modified with tetraethylenepentamine (TEPA) via an impregnation method. Characterization through X‐ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, and N2 adsorption–desorption revealed that acidic treatment removed impurities, enhancing BET (Brunauer–Emmett–Teller) surface area. TEPA modification significantly increased CO2 adsorption capacity by providing more active sites. Notably, 30TEPA/HATP exhibited the best performance at 3.28 mmol g−1. Optimal CO2 adsorption occurred at 60 °C in simulated flue gas, with water improving amine utilization. Furthermore, 30TEPA/HATP demonstrated consistent CO2 adsorption capacity (3.04 mmol g−1) across concentrations (10–20 vol%) and maintained stability after ten cycles, experiencing only a 7.0% decrease.CONCLUSIONThe findings underscore the success of low‐cost ATP, modified with TEPA, in achieving excellent CO2 capture and stability under diverse flue gas conditions. This material holds promise for practical engineering applications in mitigating carbon emissions from fossil fuel power plants. © 2024 Society of Chemical Industry (SCI).