Use of NH4Cl for activation of carbon xerogel to prepare a novel efficacious adsorbent for benzene removal from contaminated air streams in a fixed-bed column

Ayoob Rastegar; Mitra Gholami; Ahmad Jonidi Jafari; Ahmad Hosseini-Bandegharaei; Majid Kermani; Yeganeh Kosar Hashemi

doi:10.1007/s40201-020-00533-5

Use of NH₄Cl for activation of carbon xerogel to prepare a novel efficacious adsorbent for benzene removal from contaminated air streams in a fixed-bed column

J Environ Health Sci Eng. 2020 Oct 4;18(2):1141-1149. doi: 10.1007/s40201-020-00533-5. eCollection 2020 Dec.

Authors

Ayoob Rastegar^{1

2}, Mitra Gholami^{2

3}, Ahmad Jonidi Jafari^{2

3}, Ahmad Hosseini-Bandegharaei^{1

4}, Majid Kermani^{2

3}, Yeganeh Kosar Hashemi⁵

Affiliations

¹ Department of Environmental Health Engineering, School of Public Health, Sabzevar University of Medical Sciences, Sabzevar, Iran.
² Department of Environmental Health Engineering, School of Public Health, Iran University of Medical Sciences, Tehran, Iran.
³ Research Center for Environmental Health Technology, Iran University of Medical Sciences, Tehran, Iran.
⁴ Department of Chemistry, Semnan University, Semnan, Iran.
⁵ Department of Natural Resources and Environment, Science and Research Branch, Islamic Azad University, Tehran, Iran.

Abstract

Background: Ammonium chloride as an explosive salt has proved to be a prominent activation agent for adsorbents and increase the specific surface area and volume of cavities. In this work, the ability of this substance was scrutinized for activation of carbon aerogel to prepare an efficient adsorbent for benzene removal from air streams.

Methods: A carbon xerogel was fabricated from Novallac polymer and activated by ammonium chloride.The changes in structure and morphology were considered via Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), Fourier transform infrared (FTIR), Barrett-Joyner-Halenda (BJH), and energy dispersive X-ray (EDX) analyses. Also, comprehensive studies were conducted to vouchsafe the properties of the new adsorbent for benzene removal, using a fixed-bed column mode.

Results: The results showed both the successful synthesis and the suitability of the activation process. ACX possessed a higher specific surface area (1008 g/m³), compared to the parent carbon xerogel (CX; 543.7 g/m³) and organic xerogel (OX; 47 g/m³), as well as a higher adsorption capacity.

Conclusion: NH₄CL is a very beneficial for modifying the structure and morphology of carbon aerogel, and the dynamic behavior of the column with respect inlet benzene concentration can be explained by Yan-Nelson model.

Keywords: Activation; Benzene; Carbon; Modeling; NH4Cl; Xerogel.