Center of Excellence for Membrane Science and Technology, Department of Chemical, Petroleum and Gas Engineering, Iran University of Science and Technology (IUST), Narmak, Tehran, Iran.
Center of Excellence for Membrane Science and Technology, Department of Chemical, Petroleum and Gas Engineering, Iran University of Science and Technology (IUST), Narmak, Tehran, Iran.
Chemosphere. 2020 Aug;253:126647. doi: 10.1016/j.chemosphere.2020.126647. Epub 2020 Apr 4.
There is a knowledge gap for the application of one-dimensional graphene in the adsorption process. Our hypothesis was based on the fact that graphene oxide nanoribbons (GONRs) as one-dimensional graphene with more desired edges and specific surface area than other carbonaceous nanomaterials have more oxygen containing functional groups (active sites) on their edges and basal planes and therefore are more capable in adsorption of pollutants. In this regard, we synthesized GONRs by unzipping of multi-walled carbon nanotubes (MWCNTs) and investigated the adsorption behavior of GONRs by ultrasonic-assisted adsorptive removal of As(V) and Hg(II) ions from aqueous solution. The obtained results showed that As(V) ions are more favorably adsorbed onto the GONRs than Hg(II) ions and with increasing initial As(V) and Hg(II) ions concentration to 300 ppm, the equilibrium adsorption uptake of the synthesized GONRs increases to 155.61 and 33.02 mg/g for As(V) and Hg(II) ions, respectively through a rapid separation process in just 12 min. Also, three kinetic models and Freundlich and Langmuir adsorption isotherms were applied to evaluate the obtained experimental results. Our findings highlight the potential application of GONRs as one-dimensional graphene adsorbent with more desired edges than MWCNTs and graphene oxide (GO) and high adsorption capacity for selective removal of heavy metals.
在吸附过程中，一维石墨烯的应用存在知识空白。我们的假设基于以下事实：氧化石墨烯纳米带（GONRs）作为一维石墨烯，具有比其他碳质纳米材料更多的理想边缘和比表面积，因此在边缘和基面具有更多含氧官能团（活性位点），因此更能吸附污染物。在这方面，我们通过多壁碳纳米管（MWCNTs）的解卷合成了 GONRs，并通过超声辅助吸附去除水溶液中的 As(V)和 Hg(II)离子来研究 GONRs 的吸附行为。所得结果表明，与 Hg(II)离子相比，GONRs 更有利于吸附 As(V)离子，并且随着初始 As(V)和 Hg(II)离子浓度增加到 300 ppm，合成的 GONRs 的平衡吸附量分别增加到 155.61 和 33.02 mg/g ，对于 As(V)和 Hg(II)离子，通过仅 12 分钟的快速分离过程。此外，还应用了三种动力学模型和 Freundlich 和 Langmuir 吸附等温线来评估获得的实验结果。我们的研究结果强调了 GONRs 作为一维石墨烯吸附剂的潜在应用，其边缘比 MWCNTs 和氧化石墨烯（GO）更理想，并且具有选择性去除重金属的高吸附能力。
