Laboratory of Microbial Ecology and Technology (LabMET), Ghent University, Coupure Links 653, B-9000 Gent, Belgium.
Water Res. 2010 Mar;44(5):1498-506. doi: 10.1016/j.watres.2009.10.041. Epub 2009 Nov 3.
There is an increasing concern about the fate of iodinated contrast media (ICM) in the environment. Limited removal efficiencies of currently applied techniques such as advanced oxidation processes require more performant strategies. The aim of this study was to establish an innovative degradation process for diatrizoate, a highly recalcitrant ICM, by using biogenic Pd nanoparticles as free suspension or immobilized in polyvinylidene fluoride (PVDF) and polysulfone (PSf) membranes. As measured by HPLC-UV, the removal of 20mg L(-1) diatrizoate by a 10mg L(-1) Pd suspension was completed after 4h at a pH of 10. LC-MS analysis provided evidence for the sequential hydrodeiodination of diatrizoate. Pd did not lose its activity after incorporation in the PVDF and PSf matrix and the highest activity (k(cat)=30.0+/-0.4h(-1) L g(-1) Pd) was obtained with a casting solution of 10% PSf and 500mg L(-1) Pd. Subsequently, water containing 20mg L(-1) diatrizoate was treated in a membrane contactor, in which the water was supplied at one side of the membrane while hydrogen was provided at the other side. In a fed batch configuration, a removal efficiency of 77% after a time period of 48h was obtained. This work showed that membrane contactors with encapsulated biogenic nanoparticles can be instrumental for treatment of water contaminated with diatrizoate.
人们越来越关注环境中碘造影剂（ICM）的命运。目前应用的高级氧化工艺等技术的去除效率有限，因此需要更高效的策略。本研究的目的是通过使用生物合成的钯纳米颗粒作为游离悬浮体或固定在聚偏二氟乙烯（PVDF）和聚砜（PSf）膜中，为高度难降解的碘曲仑建立一种创新的降解工艺。通过 HPLC-UV 测定，在 pH 值为 10 时，10mg/L 的钯悬浮液在 4 小时内即可去除 20mg/L 的碘曲仑。LC-MS 分析为碘曲仑的顺序氢脱碘提供了证据。钯在掺入 PVDF 和 PSf 基质后并未失去其活性，在 10% PSf 和 500mg/L Pd 的铸膜液中获得了最高的活性（k(cat)=30.0+/-0.4h(-1) L g(-1) Pd）。随后，在膜接触器中处理含有 20mg/L 碘曲仑的水，其中水在膜的一侧供应，氢气在另一侧供应。在分批进料配置中，经过 48 小时后，去除效率达到 77%。这项工作表明，含有封装生物合成纳米颗粒的膜接触器可用于处理受碘曲仑污染的水。
