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Indexed by:Journal Papers

Date of Publication:2020-03-01

Journal:JOURNAL OF ENERGY CHEMISTRY

Included Journals:EI、SCIE

Volume:42

Page Number:56-61

ISSN No.:2095-4956

Key Words:Carbon monoliths; High mechanical strength; Adsorption; Gas separation

Abstract:Porous carbon materials with developed porosity, high surface area and good thermal- and chemical-resistance are advantageous for gas adsorption and separation. However, most carbon adsorbents are in powder form which exhibit high pressure drop when deployed in practical separation bed. While monolithic carbons have largely addressed the pulverization problem and preserved kinetics and usually suffer from abrasion during multiple adsorption-desorption cycles. Herein, we proposed the designed synthesis of mechanically robust carbon monoliths with hierarchical pores, solid nitrogen-containing framework. The synthesis started with the polymerization of resorcinol and formaldehyde under weakly acidic conditions generated from cyanuric acid, and then an appropriate amount of hexamethylenetetramine (HMTA) was added as a crosslinker to prompt the formation of three dimensional frameworks. After carbonization process, the as-obtained porous carbon monoliths have a high radial compressive strength of 886 N/cm as well as a BET specific surface area of up to 683 m(2)/g. At approximately 1 bar, the CO2 equilibrium capacities of the monoliths are in the range of 3.1-4.0 mmol/g at 273 K and of 2.3-3.0 mmol/g at 298 K, exhibiting high selectivity for the capture of CO2 over N-2 from a stream which consists of 16.7% (v%) CO2 in N-2. Meanwhile, they undergo a facile CO2 release in an argon stream at 298 K, indicating a good regeneration capacity. After cycle testing, sieving and regeneration, the adsorbent has no mass loss, compared to that of its fresh counterpart. (C) 2019 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.