Abstract
Polyaniline (PANI)-derived carbon has been applied in various adsorptions because of the presence of nitrogen and relatively high porosity. In this study, melamine/PANI mixture was pyrolyzed at low temperatures (500–650 °C) to derive porous carbons with high nitrogen content because of added melamine. Obtained carbons (Melamine/PANI-derived Carbons, MPCs) were characterized and applied in CO2 adsorption under low pressure, and MPC-550 (prepared at 550 °C) showed much better performance than PC-550, derived from pure PANI, because of high N content (since N leads to polarity and basicity, which are helpful for CO2 adsorption) and narrow pores (even with low porosity). For example, MPC-550 and PC-550 (prepared at 550 °C) had adsorption capacity of 1.2 and 1.0 mmol/g (at 0.15 atm); and isosteric heat of adsorption (IHA) at zero coverage of 46 and 32 kJ/mol, respectively. On the other hand, N2 adsorption relied mainly on porosity; therefore, MPC-550 had lower N2 adsorption than PC-550. Accordingly, MPC-550 and PC-550 showed ideal adsorbed solution theory selectivity (CO2/N2) of 75 and 61, respectively, under 1 atm. MPC-550 had competitive selectivity compared with other carbon-based adsorbents. MPC-500, prepared at 500 °C, showed very high selectivity (110) and IHA (48 kJ/mol); however, had relatively low CO2 adsorption because of low porosity. Based on the advantages of MPC-550, compared with those of PC-550, adding nitrogenous compounds (like melamine) to PANI, before pyrolysis, is one of the recommendable methods for porous carbons, especially with high N content. Finally, MPC-550 was recyclable in CO2 adsorption and can be suggested as a promising adsorbent for CO2 capture from offgas.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.