Journal
ENVIRONMENTAL POLLUTION
Volume 270, Issue -, Pages -Publisher
ELSEVIER SCI LTD
DOI: 10.1016/j.envpol.2020.116239
Keywords
Commercial activated carbon; Surface modification strategies; Benzene vapor adsorption; Breakthrough analysis; Kinetic modeling
Categories
Funding
- National Research Foundation of Korea (NRF) - Ministry of Science, ICT & Future Planning [2016R1E1A1A01940995]
Ask authors/readers for more resources
Facile modification of activated carbon with different functional groups showed varying adsorption performance in capturing benzene, with surface chemistry and textural properties playing a critical role in upgrading air/gas purification systems.
Facile modification is a common, but effective, option to improve the uptake removal capacity of of activated carbon (AC) against diverse target volatile organic compounds (VOCs; e.g., benzene) in gaseous streams. To help design the routes for such modification, this research built strategies to generate three types of modified ACs by incorporating amine/sulfur/amino-silane groups under solvothermal or microwave (MW) thermal conditions. The adsorption performance has been tested using a total of six types of AC sorbents (three modified + three pristine forms) for the capture of 1 Pa benzene (1 atm and 298 K). The obtained results are evaluated in relation to their textural properties and surface functionalities. Accordingly, the enhancement of AC surface basicity (e.g., point of zero charge (PZC) = 10.25), attained via the silylation process, is accompanied by the reduced adsorption of benzene (a weak base). In contrast, ACs amended with amine/sulfur (electron-donating) groups using the MW technique are found to acquire high surface acidity (PZC of 5.99-6.05) to exhibit significantly improved benzene capturing capability (relative to all others). Their uplifted performance is demonstrated in terms of key performance metrics such as breakthrough volume (BTV10%: 163 -> 443 L g(-1)), adsorption capacity (Q10%: 4.82 -> 13.6 mg g(-1)), and partition coefficient (PC10%: 0.516 -> 1.67 mol kg(-1) Pa-1). Based on the kinetic analysis, the overall adsorption process is found to be governed by pore diffusion as the main rate-determining step, along with surface interaction mechanisms. The results of this research clearly support the critical role of surface chemistry of AC adsorbents and their textural properties in upgrading air/gas purification systems. (C) 2020 Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available