Sulfur-anchored palm shell waste-based activated carbon for ultrahigh sorption of Hg(II) for in-situ groundwater treatment

So Yeon Yoon; Seok Byum Jang; Kien Tiek Wong; Hyeseong Kim; Min Ji Kim; Choe Earn Choong; Jae-Kyu Yang; Yoon-Young Chang; Sang-Eun Oh; Yeomin Yoon; Min Jang

doi:10.1016/j.jhazmat.2021.125995

Sulfur-anchored palm shell waste-based activated carbon for ultrahigh sorption of Hg(II) for in-situ groundwater treatment

J Hazard Mater. 2021 Sep 5:417:125995. doi: 10.1016/j.jhazmat.2021.125995. Epub 2021 May 7.

Authors

Affiliations

¹ Department of Environmental Engineering, Kwangwoon University, 20 Kwangwoon-Ro, Nowon-Gu, Seoul 01897, Republic of Korea.
² Department of Environmental Engineering, Kwangwoon University, 20 Kwangwoon-Ro, Nowon-Gu, Seoul 01897, Republic of Korea. Electronic address: cce_@live.com.
³ Department of Biological Environment, Kangwon National University, 192-1 Hyoja-dong, Gangwon-do, Chuncheon-si 200-701, Republic of Korea.
⁴ Department of Civil and Environmental Engineering, University of South Carolina, 300 Main Street, Columbia, SC 29208, USA.
⁵ Department of Environmental Engineering, Kwangwoon University, 20 Kwangwoon-Ro, Nowon-Gu, Seoul 01897, Republic of Korea. Electronic address: minjang@kw.ac.kr.

PMID: 34004581
DOI: 10.1016/j.jhazmat.2021.125995

Abstract

This study utilized a facile and scalable one-pot wet impregnation method for Hg(II) adsorption to prepare sulfur-anchored palm shell waste activated carbon powder (PSAC-S). The experimental results revealed that the sulfur precursors promote the surface charge on the PSAC and enhance Hg(II) removal via the Na₂S > Na₂S₂O₄ > CH₃CSNH₂ sequence. PSAC-S prepared using Na₂S had significant Hg(II) sorption efficiencies, achieving a maximum sorption capacity of 136 mg g^-1 from the Freundlich model. Compared to PSAC, PSAC-S had an enhancement in Hg(II) sorption behavior for heterogeneous interactions with sulfur. PSAC-S also demonstrated high Hg(II) sorption capacities over a wide range of solution pH, while ionic strength had an insignificant impact on Hg(II) removal efficiencies. Through various spectroscopic analyses, we identified the mechanisms of Hg(II) removal by PSAC-S as electrostatic interactions, Hg-Cl complexation, and precipitation as HgSO₄. Moreover, PSAC-S unveiled high adsorption affinity and Hg(II) stability in actual groundwater (even in µg L^-1 level). These overall results show the potentials of PSAC-S as an alternative, easily scalable material for in-situ Hg(II) remediation.

Keywords: Adsorption; Mercury; Palm shell activated carbon; Sulfur.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adsorption
Charcoal
Groundwater*
Mercury*
Sulfur

Substances

Charcoal
Sulfur
Mercury