Development of zeolite adsorbent efficiency using amine solution for carbon dioxide capture technology

NaA zeolites were developed to support amine-based adsorbents for CO2 capture in fixed-bed adsorption. Through surface functional group analysis, crystal phase identification, and specific surface area measurements, it was determined that NaA zeolite with an average pore size of 25.94 nm had the highest amine loading capacity. Four amines (MEA, PEI, and TEA) were loaded onto NaA zeolites, with the 3% PEI-modified powdered zeolite showing the highest CO2 adsorption capacity of 5.82 mmol/g. However, when the samples were converted to bead form, the CO2 adsorption capacity decreased to 3.50 mmol/g, representing a 39.86% reduction. This decrease suggests that the binder may have partially obstructed the mesopores within the NaA zeolite structure. Despite this, the bead form exhibited the highest CO2/N2 selectivity of 70 among all samples, indicating enhanced gas separation performance. The PEI-loaded NaA zeolite was identified as a highly effective CO2 adsorbent, with amine functional groups acting as active sites for chemical adsorption. The CO2 adsorption data followed the Langmuir adsorption model, suggesting a monolayer adsorption mechanism. The low PEI concentration in NaA zeolite provides a cost-effective approach for CO2 capture, showing promise for future applications in gas mixture separation.