The graphene coated iron oxide (GCIO) was used for removal of Pb2+ and As3+ ions from aqueous solution. For characterization of GCIO several techniques (FTIR, XRD, EDX, SEM, TEM, TGA, DSC, and vibrating sample magnetometry) were used to which also indicated interaction of Pb2+ and As3+ with adsorbent. In addition, effects of adsorbate concentration, different composition of adsorbent, temperature, pH of the solution & contact time of adsorbate-adsorbent were studied. After analysis of these experiments it was found that GCIO offered very fast removal of Pb2+ and As3+ with small amount of GCIO (0.09 g) in 100 mg/L adsorbate solution. The maximum removal of Pb2+ ions (up to 97.62%) achieved when treated with 100 mg/L standard solution for 35 min at 450C in weak acidic medium (5 pH). The adsorption of Pb2+ ions followed Freundlich model with high correlation coefficient 0.98 R2. In case of As3+ ion, maximum removal of metal ion (up to 86.62%) attained when 100 mg/L adsorbate solution is treated for 25 minute in slightly acidic medium (6 pH) at 250C temperatures. The adsorption of As3+ ions followed D-R model with 0.98 R2 value. The adsorption of both metal ions (Pb2+ and As3+) follow second-order-kinetic model. The high percentage removal of metal ions with little quantity of GCIO confirmed that GCIO is an excellent, effective and economic adsorbent.

中文翻译：

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用于去除铅和砷离子的高效石墨烯涂层氧化铁 (GCIO) 纳米吸附剂

石墨烯包覆的氧化铁 (GCIO) 用于从水溶液中去除 Pb2+ 和 As3+ 离子。为了表征 GCIO，使用了几种技术（FTIR、XRD、EDX、SEM、TEM、TGA、DSC 和振动样品磁力计），这些技术也表明 Pb2+ 和 As3+ 与吸附剂的相互作用。此外，还研究了吸附质浓度、不同吸附剂组成、温度、溶液pH值和吸附质-吸附剂接触时间的影响。对这些实验进行分析后发现，GCIO 在 100 mg/L 吸附物溶液中使用少量 GCIO (0.09 g) 可以非常快速地去除 Pb2+ 和 As3+。当用 100 mg/L 标准溶液在 450°C 弱酸性介质（5 pH 值）中处理 35 分钟时，可最大程度去除 Pb2+ 离子（高达 97.62%）。Pb2+离子的吸附遵循Freundlich模型，相关系数为0.98 R2。对于 As3+ 离子，当 100 mg/L 吸附质溶液在 250°C 温度下在微酸性介质（6 pH 值）中处理 25 分钟时，金属离子的去除率最高（高达 86.62%）。As3+ 离子的吸附遵循 DR 模型，R2 值为 0.98。两种金属离子（Pb2+ 和 As3+）的吸附遵循二级动力学模型。GCIO 含量低，金属离子去除率高，证明 GCIO 是一种优良、有效和经济的吸附剂。98 R2 值。两种金属离子（Pb2+ 和 As3+）的吸附遵循二级动力学模型。GCIO 含量低，金属离子去除率高，证明 GCIO 是一种优良、有效和经济的吸附剂。98 R2 值。两种金属离子（Pb2+ 和 As3+）的吸附遵循二级动力学模型。GCIO 含量低，金属离子去除率高，证明 GCIO 是一种优良、有效和经济的吸附剂。