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.

 抽象的

本研究首次证明了由香蒲茎合成的胺接枝磁性氧化石墨烯（m-GO-NH ₂ ）在去除汞（Hg（II））和2,4,6-三硝基苯酚（TNP）方面的突出潜力。 m-GO-NH ₂的吸附性能通过考虑接触时间（0-120 分钟）、pH（2-9）、吸附剂剂量（5-40 mg）和吸附物浓度（10-50）的影响来评价。毫克/升）。使用 30 mg 吸附剂剂量分别在 90 分钟和 75 分钟内获得最大 Hg (II) 和 TNP 去除率 (∼ 100%)。 m-GO-NH ₂在pH 7、20 mg/L Hg (II) 和pH 2、30 mg/L TNP 时观察到最佳性能。根据Brunauer-Emmett-Teller (BET)分析，GO的表面积为34.81 m ² /g，同时观察到微孔和中孔。关于热力学研究，Hg (II) 的吸附过程是自发的吸热过程，遵循 Redlich-Peterson (RP) 和 Freundlich 等温方程，而 TNP 的吸附过程是放热的，与 Langmuir 和 RP 等温线拟合良好。动力学数据也表明与伪二阶模型具有良好的相关性。 Hg (II) 和 TNP 的最高吸附容量估计分别为 107.33 和 105.2 mg/g。因此，所提出的m-GO-NH ₂可以成为消除金属和有机污染物的有前途的吸附剂。