Graphene oxide-based dendritic adsorbent for the excellent capturing of platinum group elements

Haribandhu Chaudhuri; Xiaoyu Lin; Yeoung-Sang Yun

doi:10.1016/j.jhazmat.2023.131206

Graphene oxide-based dendritic adsorbent for the excellent capturing of platinum group elements

J Hazard Mater. 2023 Jun 5:451:131206. doi: 10.1016/j.jhazmat.2023.131206. Epub 2023 Mar 13.

Authors

Haribandhu Chaudhuri¹, Xiaoyu Lin², Yeoung-Sang Yun³

Affiliations

¹ School of Chemical Engineering, Jeonbuk National University, 567 Beakje-dearo, Deokjin-gu, Jeonju, Jeonbuk 54896, Republic of Korea.
² Division of Semiconductor and Chemical Engineering, Jeonbuk National University, 567 Beakje-dearo, Deokjin-gu, Jeonju, Jeonbuk 54896, Republic of Korea.
³ School of Chemical Engineering, Jeonbuk National University, 567 Beakje-dearo, Deokjin-gu, Jeonju, Jeonbuk 54896, Republic of Korea; Division of Semiconductor and Chemical Engineering, Jeonbuk National University, 567 Beakje-dearo, Deokjin-gu, Jeonju, Jeonbuk 54896, Republic of Korea. Electronic address: ysyun@jbnu.ac.kr.

PMID: 36931220
DOI: 10.1016/j.jhazmat.2023.131206

Abstract

Herein, we report amino functionalized thermally stable graphene oxide-based dendritic adsorbent (GODA) with the highest sorption capacity ever recorded for platinum group elements (PGEs), including platinum (Pt(IV), PtCl₆^2-) and palladium (Pd(II), PdCl₄^2-), from highly acidic aqueous solutions. The GODA was designed and synthesized to have fully ionized amine binding sites and was characterized in detail. The detail batch adsorption experiment along with kinetic, isotherm, and thermodynamic studies were carried out to investigate the adsorption efficacy of GODA. For both Pt(IV) and Pd(II), the experimental data are more accurately fitted with the pseudo-second-order and the intraparticle diffusion kinetic models and Langmuir isotherm model as compared to the pseudo-first-order kinetic model and Freundlich and Temkin isotherm models, respectively. The material showed the highest ever adsorption capacities of 827.8 ± 27.7 mg/g (4.24 ± 0.00 mmol/g) and 890.7 ± 29.1 mg/g (8.37 ± 0.00 mmol/g) for Pt(IV) and Pd(II), respectively, at pH 1. The adsorption equilibriums were achieved within 70 min and 65 min for Pt(IV) and Pd(II), respectively. The thermodynamic parameters indicate that the adsorptions of both metals are spontaneous. The binding mechanisms are considered to be electrostatic interactions, hydrogen bonding, cationic-π bonding, and surface complexation between the sorbent and the sorbates. Furthermore, the as-prepared GODA exhibited high thermal stability and significant acid-resistance at pH 1. The GODA demonstrated excellent regeneration and reusability for Pt(IV) and Pd(II) over five adsorption/desorption cycles, indicating its excellence in practical applications.

Keywords: Dendritic adsorbent; Excellent adsorptions and regenerations; Graphene oxide-based adsorbent; High acid resistance and thermal stability; Platinum group elements.