Project 5: Novel Filtration Devices for Arsenic Reduction

摘要：项目5 在美国，14%的美国人依赖私人威尔斯井作为饮用水源。在北卡罗来纳州， 人为污染物（例如，无机砷（iAs）、锰、铬和钒）渗透 私人威尔斯井，使居民面临健康后果的风险（例如，与iAs暴露相关的糖尿病）。一个 据估计，约有300万人（占北卡罗来纳州人口的三分之一）饮用私人威尔斯井中的水 iAs浓度高达800 µg/L。美国EPA和NC-DHHS推荐反渗透膜 过滤和固体介质来去除井水中的iAs，因为这些技术需要最少的化学品 和步骤，以消除iA和易于实施。然而，这两个重要的挑战 在这种情况下的技术是：（i）不充分地去除As（III）（即，最危险的iAs种类）， 和（ii）产生富含砷的废物。在这两种技术中，膜技术最适合处理地下水 因为与固体介质相比，它们在去除As（III）方面更有效，更容易操作， 紧凑，并提供更快的清洁用水。然而，膜系统允许富含砷的盐水重新 进入水循环，并且不是专门设计用于去除iAs和共存污染物（CC）的。 可以说，固体介质相对于膜的最有价值的优点是， 更容易处理。我们假设，一个集成的膜吸附剂系统将去除iAs和 地下水中的氯化碳比现有的家庭水处理系统具有更好的功效， 最大限度地减少iAs重新进入环境。因此，项目5与UNC-SRP的主题相一致 中心，“确定减少iAs暴露的新方法并阐明iAs的潜在机制- 诱发的代谢功能障碍，并着眼于预防疾病”， 利用假设驱动的研究，为受暴露影响的社区开发面向产品的解决方案 到iA和CC。项目5将填补研究空白，以便：（一）开发有效去除砷的技术（三） （ii）优化膜去除iAs，特别是As（III）的能力， 不损害水的生产率;（iii）开发吸附剂来处理含砷的膜盐水;（iv） 引入去除地质和人为CC的概念（即，Mn（II），Cr，V） 主要关注污染物（iAs）;以及（v）引入生物医学指标来评估iAs的性能 膜过滤系统我们将通过三个具体目标来实现我们的目标：第一，我们将发展和 通过将聚酰胺、磺化聚醚、聚乙烯醇 第二，我们将优化聚乙烯亚胺（PEI）， 第三，我们将部署一个集成的颗粒吸附剂，用于从膜盐水中去除iAs和CCs; 膜吸附剂系统原型，并评估其在受影响的NC社区的性能稳定性。

ABSTRACT: PROJECT 5 In the US, 14% of Americans rely on private wells as their drinking water source. In NC, geogenic and anthropogenic contaminants (e.g., inorganic arsenic (iAs), manganese, chromium, and vanadium) infiltrate private wells, placing residents at risk for health outcomes (e.g., diabetes associated with iAs exposure). An estimated ~3 million individuals representing one-third of the population in NC drink water from private wells with iAs concentrations up to 800 µg/L. The US EPA and NC-DHHS recommend reverse osmosis membrane filtration and solid media to remove iAs from well water because these technologies require the fewest chemicals and steps to remove iAs and are easy to implement. However, two important challenges to these two technologies in this context are that both: (i) inadequately remove As(III) (i.e., the most hazardous iAs species), and (ii) produce iAs-enriched waste. Of the two technologies, membranes are best suited to treat groundwater because compared to solid media, they are more effective at removing As(III), are easier to operate, are more compact, and afford faster access to clean water. However, membrane systems allow iAs-enriched brines to re- enter into the water cycle and are not designed specifically to remove iAs and co-occurring contaminants (CCs). Arguably, the most valuable advantage solid media has over membranes is that the resulting iAs-enriched waste is easier to dispose. We hypothesize that an integrated membrane-sorbent system will remove iAs and CCs from groundwater with better efficacy than existing in-home water treatment systems, while minimizing iAs re-entry into the environment. Project 5 therefore aligns with the theme of the UNC-SRP Center, “Identifying novel methods to reduce iAs exposure and elucidating mechanisms underlying iAs- induced metabolic dysfunction with a vision for disease prevention” and addresses SRP Mandate 4 in using hypothesis-driven research to develop a product-oriented solution for communities affected by exposure to iAs and CCs. Project 5 will address research gaps to: (i) develop technologies that effectively remove As(III) from water without chemical pretreatment; (ii) optimize the ability of membranes to remove iAs, especially As(III), without compromising water productivity; (iii) develop sorbents to treat iAs-containing membrane brines; (iv) introduce the concept of removing geogenic and anthropogenic CCs (i.e., Mn(II), Cr, V) from waters in addition to the primary contaminant of concern (iAs); and (v) introduce biomedical metrics to assess performance of iAs membrane filtration systems. We will accomplish our goals with three specific aims: First, we will develop and optimize membranes to remove iAs and CCs from groundwater by combining polyamide, sulfonated poly(ether ether ketone) (sPEEK), and/or mixed-matrix chemistries; Second, we will optimize a polyethylenimine (PEI)- based granular sorbent for iAs and CCs removal from membrane brine; Third, we will deploy an integrated membrane-sorbent system prototype and evaluate it for performance stability in impacted NC communities.