Yantasee Wassana, Warner Cynthia L, Sangvanich Thanapon, Addleman R Shane, Carter Timothy G, Wiacek Robert J, Fryxell Glen E, Timchalk Charles, Warner Marvin G
Pacific Northwest National Laboratory, Richland, Washington 99352, USA.
Environ Sci Technol. 2007 Jul 15;41(14):5114-9. doi: 10.1021/es0705238.
We have shown that superparamagnetic iron oxide (Fe3O4) nanoparticles with a surface functionalization of dimercaptosuccinic acid (DMSA) are an effective sorbent material for toxic soft metals such as Hg, Ag, Pb, Cd, and Tl, which effectively bind to the DMSA ligands and for As, which binds to the iron oxide lattices. The nanoparticles are highly dispersible and stable in solutions, have a large surface area (114 m2/g), and have a high functional group content (1.8 mmol thiols/g). They are attracted to a magnetic field and can be separated from solution within a minute with a 1.2 T magnet. The chemical affinity, capacity, kinetics, and stability of the magnetic nanoparticles were compared to those of conventional resin based sorbents (GT-73), activated carbon, and nanoporous silica (SAMMS) of similar surface chemistries in river water, groundwater, seawater, and human blood and plasma. DMSA-Fe3O4 had a capacity of 227 mg of Hg/g, a 30-fold larger value than GT-73. The nanoparticles removed 99 wt% of 1 mg/L Pb within a minute, while it took over 10 and 120 min for Chelex-100 and GT-73 to remove 96% of Pb.
我们已经表明，表面用二巯基琥珀酸（DMSA）功能化的超顺磁性氧化铁（Fe3O4）纳米颗粒是一种有效的吸附剂材料，可用于吸附汞、银、铅、镉和铊等有毒软金属，这些金属能有效结合到DMSA配体上，同时也可吸附与氧化铁晶格结合的砷。这些纳米颗粒在溶液中具有高度分散性和稳定性，具有较大的表面积（114平方米/克），且官能团含量高（1.8毫摩尔硫醇/克）。它们会被磁场吸引，用1.2特斯拉的磁体可在一分钟内从溶液中分离出来。在河水、地下水、海水以及人体血液和血浆中，将磁性纳米颗粒的化学亲和力、容量、动力学和稳定性与具有相似表面化学性质的传统树脂基吸附剂（GT - 73）、活性炭和纳米多孔二氧化硅（SAMMS）进行了比较。DMSA - Fe3O4对汞的吸附容量为227毫克/克，是GT - 73的30倍。这些纳米颗粒在一分钟内可去除1毫克/升铅中的99%（重量），而Chelex - 100和GT - 73去除96%的铅则分别需要10分钟以上和120分钟。
