A novel carbonized polydopamine (C‐PDA) adsorbent with high CO₂ adsorption capacity and water vapor resistance

Abstract

Novel carbonized polydopamine adsorbents (C‐PDAs) with high surface area, high CO 2 adsorption capacity and superior moisture resistance performance were prepared by one‐step synthesis method using polydopamine as carbon precursor at different KOH/C ratios, and then characterized. CO 2 and water vapor adsorption performances of C‐PDAs were examined separately by static adsorption and fixed‐bed experiments. Results showed that BET area and pore volume of C‐PDA‐4 were up to 3342 m 2 /g and 2.01 cm 3 /g, respectively. Its CO 2 adsorption capacity reached up to 30.5 mmol/g at 25 bar, much higher than many other adsorbents including metal‐organic frameworks (MOFs). C‐PDAs prepared with high KOH/C ratios had low surface element concentrations of O and N resulting in low surface hydrophilic property. H 2 O(g) isotherm of C‐PDA was much lower than those on Mg‐MOF‐74, Cu‐BTC, and MIL‐101(Cr). Fixed‐bed experiments showed that co‐presence of water vapor in feed stream with 30% RH had negligible impact on CO 2 working capacity of C‐PDA. © 2016 American Institute of Chemical Engineers AIChE J , 62: 3730–3738, 2016