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.
Keywords: Hg (II); M-GO-NH2; TNP; adsorption; isotherm.