Aung Myat Thandar, Shimabuku Kyle K, Soares-Quinete Natalia, Kearns Joshua P
Aqueous Solutions, Yangon, Myanmar (Burma).
Gonzaga University, Spokane WA, United States.
Water Res. 2022 Apr 15;213:118146. doi: 10.1016/j.watres.2022.118146. Epub 2022 Feb 1.
Carbon adsorbent fouling by dissolved organic matter (DOM) inhibits the ability of the widely-used rapid small-scale column test (RSSCT) to accurately predict the removal of organic micropollutants (OMP) from water by full-scale carbon adsorbers. Here, the adsorption of 11 short-chain per-/poly-fluoroalkyl substances (PFAS) from groundwater, surface water, and wastewater was examined in pilot columns as well as RSSCTs using constant diffusivity (CD) and proportional diffusivity (PD) designs. Neither the CD- or PD-RSSCT accurately predicted pilot adsorber breakthrough of PFAS using standard diffusional mass transfer models. However, PFAS breakthrough relative to optical property (e.g., peak C, UV absorbance at 254 nm) breakthrough remained constant between pilot column, CD-RSSCT, and PD-RSSCT designs. This finding permitted accurate breakthrough predictions for the sum of PFAS and for 9 of the 11 PFAS on an individual basis in pilot columns using RSSCTs. Multiple linear regressions incorporating influent and treated water optical parameters enabled the modeling approach to be applied to water sources with heterogeneous DOM characteristics. It is hypothesized that this methodology was successful because (i) optical parameters adequately quantified the competitive nature of DOM and their adsorption behaved similar to OMP and (ii) competitive adsorption by low-molecular weight DOM was the predominant fouling mechanism. An OMP monitoring approach was developed for waters containing DOM with heterogenous characteristics that also relied on raw and treated water optical properties. UVA and fluorescence monitoring could therefore enable water treatment to remove PFAS in a variety of scenarios that face inhibitory cost and analytical limitations, such as decentralized and low-resource settings.
溶解有机物（DOM）导致的碳吸附剂污染会抑制广泛使用的快速小尺度柱试验（RSSCT）准确预测全尺寸碳吸附器从水中去除有机微污染物（OMP）的能力。在此，使用恒定扩散率（CD）和比例扩散率（PD）设计，在中试柱以及RSSCT中研究了从地下水、地表水和废水中吸附11种短链全氟/多氟烷基物质（PFAS）的情况。使用标准扩散传质模型时，CD - RSSCT或PD - RSSCT均无法准确预测中试吸附器中PFAS的穿透。然而，在中试柱、CD - RSSCT和PD - RSSCT设计之间，PFAS相对于光学性质（例如，峰值C、254nm处的紫外吸光度）穿透的情况保持恒定。这一发现使得能够在中试柱中使用RSSCT准确预测PFAS总量以及11种PFAS中9种的个体穿透情况。纳入进水和处理后水光学参数的多元线性回归使得该建模方法能够应用于具有异质DOM特征的水源。据推测，该方法之所以成功，是因为（i）光学参数充分量化了DOM的竞争性质，且其吸附行为与OMP相似，以及（ii）低分子量DOM的竞争吸附是主要的污染机制。针对含有异质特征DOM的水体开发了一种OMP监测方法，该方法同样依赖于原水和处理后水的光学性质。因此，在面临抑制成本和分析限制的各种场景中，如分散式和资源匮乏的环境中，紫外光A和荧光监测能够使水处理去除PFAS。
