ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Synthesizing nanoporous carbon from palm kernel shell as a newly designed green absorbent for removing mercury

Abubakar Lawal, Nor Azah Yusof, Abdul Halim Abdullah, Mohd Hanif Wahid, Suhainie Ismail, and Siti Fatimah Abd Rahman

Chemistry Department, Universiti Putra Malaysia, Serdang, Malaysia

E-mail: azahy@upm.edu.my

Received: 23 June 2023  Accepted: 15 November 2023

Abstract:

Nanoporous carbons (NCs) derived from palm kernel shell (PKS) have excellent properties allowing them to be used in globally challenging fields such as water treatment, pollutant and pesticide removal, catalysis, and heavy metal adsorption. In this study, PKS was chemically activated using H₃PO_4, and the effects of temperature (500 °C) and impregnation ratio on the process were investigated. The optimal conditions for the synthesis of NC with a large surface area (1280 m² g⁻¹) were a medium temperature (500 °C), an impregnation ratio of 1:1, and a carbonization time of 1 h. Various parameters including the surface area, porosity, and thermal stability of the synthesized NC were investigated. The results confirmed the potential of NC for various applications, with NC–PKS 1:1 exhibiting the best mercury (II) [Hg (II)] adsorption among the tested samples at the optimal pH, adsorbent dosage, initial concentration, and contact time. Finally, by employing a pseudo-second-order kinetic model, the Freundlich model exhibited the best adsorption isotherm fit with a maximum Hg (II) adsorption capacity of 55.3 mg/g. Therefore, the synthesized NC is a promising candidate for wastewater treatment because it is efficient and is made of an inexpensive and environmentally friendly carbon source.

Keywords: Nanoporous carbon; Palm kernel shells; Temperature; Mercury

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-023-03219-y

Chemical Papers 78 (3) 1959–1974 (2024)