Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL, USA.
Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL, USA.
Sci Total Environ. 2022 May 1;819:152886. doi: 10.1016/j.scitotenv.2021.152886. Epub 2022 Jan 6.
This study investigated the removal of selected per- and polyfluoroalkyl substances (PFAS) from water via two green sorption media (IFGEM-7 and AGEM-2). Both selected green sorption media recipes contain sand (85-91%) and clay (3-4%), in addition to recycled iron (Fe) (5-7.5%) or aluminum (Al) (4.5% in AGEM-2 only). Batch and column studies were integrated and performed using the prescribed green sorption media recipes to determine their efficiencies in removing two most targeted PFAS, including perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA). In the batch test, while the removal efficiencies of PFOS ranged from 27 to 46% and 23 to 42%, those for PFOA ranged from 6 to 16% and 5 to 18% when using IFGEM-7 and AGEM-2, respectively. The higher removal of PFOS than PFOA observed in both IFGEM-7 and AGEM-2 batch tests could be attributed to higher media affinity for sulfonate groups of PFOS when compared to the carboxylate groups of PFOA. In the column study, the initial removal (within 1 h) by IFGEM-7 was greater than 99% for PFOS and 28% for PFOA. When comparing different dynamic adsorption models, it appears that the non-linear equations could better describe the trend of experimental data compared to the linear forms of the Modified Dose Response model. Life expectancy calculations, performed for demonstration purposes of field applications, suggested that if IFGEM-7 were to be applied in a downflow filter box to treat a hypothetical volume of 60,000 L of water during an emergency response, and it may last for 1506 h (62.8 d) and 4.2 h for a target removal of 80% of PFOS and PFOA, respectively.
本研究通过两种绿色吸附介质（IFGEM-7 和 AGEM-2）研究了从水中去除选定的全氟和多氟烷基物质（PFAS）。两种选定的绿色吸附介质配方均包含 85-91%的沙子和 3-4%的粘土，以及 5-7.5%的回收铁（Fe）（仅在 AGEM-2 中为 4.5%）或铝（Al）。综合使用规定的绿色吸附介质配方进行了批处理和柱处理研究，以确定它们在去除两种最受关注的 PFAS（包括全氟辛烷磺酸（PFOS）和全氟辛酸（PFOA））方面的效率。在批处理测试中，当使用 IFGEM-7 和 AGEM-2 时，PFOS 的去除效率分别为 27-46%和 23-42%，而 PFOA 的去除效率分别为 6-16%和 5-18%。在 IFGEM-7 和 AGEM-2 的批处理测试中观察到 PFOS 的去除率高于 PFOA，这可能是由于与 PFOA 的羧酸盐基团相比，PFOS 的磺酸盐基团对介质具有更高的亲和力。在柱研究中，IFGEM-7 在 1 小时内对 PFOS 的初始去除率大于 99%，对 PFOA 的初始去除率为 28%。在比较不同的动态吸附模型时，似乎非线性方程比修正剂量响应模型的线性形式更能描述实验数据的趋势。为了展示现场应用的目的而进行的预期寿命计算表明，如果 IFGEM-7 应用于下行流过滤器盒中以处理应急响应期间假设的 60000L 水，则其可持续 1506 小时（62.8 天），对于 80%的 PFOS 和 PFOA 目标去除率，分别可持续 4.2 小时。
