High efficient Hg (II) and TNP removal by NH₂ grafted magnetic graphene oxide synthesized from Typha latifolia

ABSTRACT

The present study for the first time manifests the outstanding potential of amine grafted magnetic graphene oxide (m-GO-NH₂) synthesized from Typha latifolia stems for mercury (Hg (II)) and 2,4,6-trinitrophenol (TNP) removal. The adsorption performance of m-GO-NH₂ was apprized by considering the impact of the contact time (0–120 min), pH (2–9), adsorbent dose (5–40 mg), and adsorbate concentration (10–50 mg/L). The maximum Hg (II) and TNP removals (∼ 100%) were obtained using 30 mg adsorbent dose in 90 and 75 min, respectively. The best performance of m-GO-NH₂ was observed at pH of 7, 20 mg/L Hg (II), and pH of 2, 30 mg/L TNP. According to the Brunauer–Emmett–Teller (BET) analysis, the surface area of GO was 34.81 m²/g and the simultaneous micro and mesoporosity was observed. Regarding the thermodynamic studies, the adsorption procedure was spontaneous and endothermic for Hg (II) followed Redlich-Peterson (R-P) and Freundlich isotherm equations while it was exothermic for TNP, well fitted with Langmuir and R-P isotherms. Kinetic data also indicated a good correlation with pseudo-second-order model. The highest adsorption capacity was estimated as 107.33 and 105.2 mg/g for Hg (II) and TNP, respectively. Accordingly, the proposed m-GO-NH₂ can be a promising adsorbent for the elimination of metal and organic contaminants.

GRAPHICAL ABSTRACT

KEYWORDS:

• M-GO-NH₂
• Hg (II)
• TNP
• adsorption
• isotherm

Acknowledgments

The authors are thankful of the University of Zabol. This study was supported by the University of Zabol, office of Research through a research in No. (PR-UOZ98-4). Also, we are cordially thankful to Dr Hajar Abyar for her help during the research and final editing.

Disclosure statement

No potential conflict of interest was reported by the author(s).