Development of low-cost, high-efficiency, and environmentally benign adsorbents for mercury removal is of significant importance for environmental remediation. Herein, we report a novel porous puffed rice carbon (PRC) with co-implanted metal iron and sulfur, forming a high-quality PRC/Fe@S composite as a high-efficiency adsorbent for mercury removal from aqueous solution. The in situ-formed Fe nanoparticles in PRC are strongly coupled with sulfur via a supercritical CO2 fluid approach and dispersed homogeneously in the cross-linked hierarchical porous architecture. The pore formation mechanism of Fe on PRC is also proposed. The optimized PRC/Fe@S composite offers superior selective affinity, high removal efficiency, and ultrahigh adsorption capacity of up to 738.0 mg g-1. It is demonstrated that the hierarchical porous carbon in the PRC/Fe@S composite not only acts as a framework to stabilize and disperse Fe nanoparticles but also provides abundant pores and voids for absorbing Hg(II) from aqueous solution. More importantly, the absorbed Hg(II) can be reduced to Hg(0) by Fe and further chemically immobilized by sulfur. The enhanced coupled effect is discussed and proposed. Therefore, an innovative adsorption mechanism of adsorption-reduction-immobilization is proposed, which offers a new prospect in developing high-efficiency carbon-based adsorbents in environmental remediation.

中文翻译：

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膨化稻米碳与硫和金属铁的混合物，用于高效去除水溶液中的汞。

开发用于去除汞的低成本，高效和环境友好型吸附剂对于环境修复具有重要意义。在本文中，我们报道了一种新型的多孔膨化稻米碳（PRC），其与金属铁和硫共注入，形成了高质量的PRC / Fe @ S复合材料，作为从水溶液中去除汞的高效吸附剂。PRC中原位形成的Fe纳米粒子通过超临界CO2流体方法与硫牢固结合，并均匀地分散在交联的分层多孔结构中。还提出了Fe在PRC上的成孔机理。经过优化的PRC / Fe @ S复合材料具有出色的选择性亲和力，高去除效率和高达738.0 mg g-1的超高吸附能力。结果表明，PRC / Fe @ S复合材料中的分层多孔碳不仅起到稳定和分散Fe纳米粒子的骨架的作用，而且还提供了丰富的孔隙和空隙，可以从水溶液中吸收Hg（II）。更重要的是，被吸收的Hg（II）可以被Fe还原为Hg（0），并被硫进一步化学固定。讨论并提出了增强的耦合效应。因此，提出了一种新颖的吸附还原固定化吸附机理，为开发高效的碳基吸附剂进行环境修复提供了新的前景。Fe可以将吸收的Hg（II）还原为Hg（0），并通过硫进一步化学固定。讨论并提出了增强的耦合效应。因此，提出了一种新颖的吸附还原固定化吸附机理，为开发高效的碳基吸附剂进行环境修复提供了新的前景。Fe可以将吸收的Hg（II）还原为Hg（0），并通过硫进一步化学固定。讨论并提出了增强的耦合效应。因此，提出了一种新颖的吸附还原固定化吸附机理，为开发高效的碳基吸附剂进行环境修复提供了新的前景。