New Functionalized Mesoporous Silicas for Adsorption of Heavy Metal Ions

CTS- 0086512“新型功能化介孔二氧化硅用于重金属离子吸附“Mietek Jaroniec肯特州立大学摘要本研究项目的重点是开发具有高负载能力的重金属离子吸附剂，该吸附剂可以容易地再生和重复使用，而不会有任何明显的负载能力损失。 更具体地说，努力是合成新的介孔二氧化硅基吸附剂，用于从水溶液中去除汞离子和其他重金属离子。多孔二氧化硅表面用配体如1-苯甲酰基-3-[3-（三乙氧基甲硅烷基）丙基]硫脲和1-烯丙基-3-[3-（三乙氧基甲硅烷基）丙基]硫脲官能化，预期它们与汞和其它重金属离子的结合强度低于常用的3-巯基丙基配体。 因此，应该可以在较温和的条件下（即，而不使用浓酸），并因此防止再生时吸附能力的损失。这些吸附剂是通过自组装二氧化硅/表面活性剂介孔结构材料的直接官能化和通过高比表面积、大孔体积和容易获得的多孔结构的无表面活性剂的介孔二氧化硅的官能化来制备的。所得到的重金属离子吸附剂的性能进行了严格的评估，并正在寻求支持，功能化程序和配体的水处理的最佳组合。这项研究的直接影响将是新的、易于再生的吸附剂的可用性，用于选择性吸附沃茨中的有害重金属离子。 这项研究有望提供有价值的洞察到重要的，但在很大程度上尚未解决的问题的影响，有限的几何形状和孔径对吸附的离子和分子物种，并揭示一个潜在的有用的相关性之间的结构和类型的键合层与它们的性能在金属离子吸附。拟议研究的跨学科性质为培训研究生和本科生在学术界和工业界的一系列职业提供了独特的教育机会。此外，学生将有很好的机会参加PI在纳米结构材料的合成，功能化和应用领域建立的国际合作。

CTS- 0086512"New Functionalized Mesoporous Silicas for Adsorption of Heavy Metal Ions"Mietek JaroniecKent State UniversityABSTRACTThis research project is focused on the development of heavy-metal-ion adsorbents that would exhibit high loading capacities and could be readily regenerated and reused without any appreciable loss of the loading capacity. More specifically, the effort is to synthesize new mesoporous silica-based adsorbents for removal of mercury ions and other heavy-metal ions from aqueous solution. The porous silica surface is being functionalized with ligands such as 1-benzoyl-3-[3-(triethoxysilyl)propyl]thiourea and 1-allyl-3-[3-(triethoxysilyl)- propyl] thiourea, which are expected to bind mercury and other heavy metal ions less strongly than in the case of commonly used 3-mercaptopropyl ligands. Thus, it should be possible to regenerate these new adsorbents under milder conditions (i.e., without using concentrated acids), and consequently, to prevent the loss of adsorption capacity upon regeneration. These adsorbents are being prepared by a direct functionalization of self-assembled silica/surfactant mesostructured materials and by functionalization of surfactant-free mesoporous silicas of high specific surface areas, large pore volumes, and readily accessible porous structures. The performance of the resulting heavy-metal- ion adsorbents are critically evaluated, and the best combination of support, functionalization procedure, and ligand for water treatment is being sought. The immediate impact of the proposed research will be the availability of novel, easy-to- regenerate adsorbents for selective adsorption of harmful heavy-metal ions from waters. This study promises to provide valuable insight into important and yet largely unresolved problems of the influence of confined geometry and pore size on adsorption of ionic and molecular species and to reveal a potentially useful correlation between the structure and type of bonded layers with their performance in metal-ion adsorption. The interdisciplinary nature of the proposed research provides a unique educational opportunity for training graduate and undergraduate students for a range of careers in academia and industry. Also, students will have an excellent opportunity to participate in the international collaborations established by PI in the area of synthesis, functionalization, and application of nanostructured materials.