L-cysteine doped polypyrrole (PPy@ L-Cyst): A super adsorbent for the rapid removal of Hg+2 and efficient catalytic activity of the spent adsorbent for reuse
L-cysteine doped polypyrrole (PPy@ L-Cyst): A super adsorbent for the rapid removal of Hg+2 and efficient catalytic activity of the spent adsorbent for reuse
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DOI：
10.1016/j.cej.2018.01.093
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发表时间：
2018-08-01
影响因子：
15.1
通讯作者：
Maity, Arjun
中科院分区：
文献类型：
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作者：
Ballav, Niladri;Das, Raghunath;Maity, Arjun
全世界越来越关注检测和去除从各种来源过度释放到水环境中的最有毒的元素Hg 2+。本研究的目的是开发一种新的材料，从水介质中快速，有效地去除汞离子。采用自由基聚合法对聚吡咯进行L-半胱氨酸表面改性（PPy@ L-Cyst），制备了一种新的吸附剂，可有效去除水溶液中的Hg ~（2+）。采用FTIR、FE-SEM、HR-TEM、XRD、TGA、XPS等仪器技术对PPy@ L-Cyst复合材料吸附前和吸附后的Hg 2+离子进行了详细的表征。通过使用ICP-OES技术在不同参数下进行一系列批研究，评价了从水介质中排除Hg 2+的能力。利用不同的吸附动力学和等温线模型对实验结果进行了研究。PPy@ L-Cyst通过伪二级动力学表现出对Hg 2+离子的快速吸附，而在其他模型中，Langmuir是最佳拟合的等温模型，在25 ℃下的最大吸附容量为2042.7 mg/g。提出了吸附剂和吸附质相互作用的合理机制来解释PPy@ L-Cyst吸附行为背后的原因。此外，本研究还强调了负载有毒金属离子的废吸附剂的可重复使用性，用于催化有机转化。在苯乙炔有机转化反应中，载汞催化剂发挥了重要作用，苯乙酮的产率为52%。显然，这是一种新的方法，用于催化应用，这具有很大的环境影响，最大限度地减少废物来自传统的吸附技术的汞吸附材料的再利用。
A growing worldwide concern about the detection and removal of the most toxic element Hg2+ being released excessively into the water environment from various sources. The aim of this study is to develop a new material for rapid and efficient removal of Hg2+ ions from aqueous media. In the present study, a new adsorbent has been developed through the surface modification of polypyrrole with L-cysteine (PPy@ L-Cyst) via radical polymerization method for effectively elimination of Hg2+ from aqueous solutions. The detailed characterization of PPy@ L-Cyst composite before adsorption and together with its adsorbed Hg2+ ions after adsorption were extensively investigated using various instrumental techniques including FTIR, FE-SEM, HR-TEM, XRD, TGA, XPS. The capability of Hg2+ exclusion from aqueous medium was evaluated by performing a series of batch studies under different parameters using ICP-OES technique. The obtained experimental outcomes were investigated with the help of different adsorption kinetic and isotherm models. PPy@ L-Cyst exhibited rapid adsorption of Hg2+ ions through pseudo-second-order kinetics whereas the Langmuir was the best fitted isotherm model among other models with maximum uptake capacity of 2042.7 mg/g at 25 degrees C. A plausible mechanism for the interaction of adsorbent and adsorbate was proposed to explain the reason behind the adsorption behavior of PPy@ L-Cyst. In addition, current study also highlighted the reusability of toxic metal ions loaded spent adsorbent for the catalytic organic transformation. The mercury-laden catalysts played an important role for the organic transformation reaction of phenylacetylene to desired product, acetophenone, with 52% yield. Obviously, this is a new approach for the reuse of Hg2+ adsorbed material for catalytic application, which has a great environment impact for the minimization of waste derived from conventional adsorption techniques.