Natural gas purification and the mitigation of carbon dioxide (CO2) emissions from flue gases are critical steps in alleviating the greenhouse effect and significantly mitigate multiple environmental challenges associated with global warming. Hypercrosslinked polymers (HCPs) have become a hot topic as prospective adsorbents for gas purification and separation, owing to their low cost and scalability. Hence, TPB-Ben, TPB-Nap, and TPB-Ant were synthesized through a solvent knitting strategy, with the modification in the size of the monomers serving as a distinctive feature. This alteration aimed to explore the impact of phenyl ring quantity on the polymers' gas adsorption and separation efficiency. All HCPs showed outstanding selective separation capability of CO2 from CO2/CH4 and CO2/N2 mixtures, such as TPB-Ben-3-2 (CO2/CH4: 10.77; CO2/N2: 59.72), TPB-Nap-3-2 (CO2/CH4: 9.12; CO2/N2: 61.31), and TPB-Ant-3-2 (CO2/CH4: 10.00; CO2/N2: 62.89), which could be potential candidate adsorbents for natural gas purification and CO2 capture. Considering the mild reaction conditions, low cost, efficient gas adsorption, and the potential for scalable production, these polymers are considered ideal selective solid adsorbents for capturing CO2. This further highlights the significance of the solvent knitting strategy.
Keywords: CO2 purification; Friedel–Crafts reaction; gas separation; hypercrosslinked polymers; solvent knitting.