Intensified, High-Rate Reductive Immobilization of Hexavalent Chromium

项目摘要/摘要 六价铬，或称六价铬，是美国水资源中分布最广泛的污染物之一， 环游世界。在1,699份现任或前任国家优先事项清单中，至少有1,127份已发现CR(VI) (NPL)地点，已被美国环境保护局(EPA)确定为最严重的 这是美国最危险的废物地点，也是联邦长期清理活动的最优先目标。 毒理学研究发现，高浓度的铬(VI)可导致胃癌、肾癌 以及肝脏损伤和生殖损伤。因此，供水商和供水商之间的需求很大 超级基金网站的经理为解决铬(VI)污染的创新技术以经济高效和 以环境可持续的方式。 缺乏具有成本效益的技术来降低水中的六价铬水平是由于相关的技术挑战 利用现有的物理/化学方法，包括高成本，需要处置二次废物 河流，以及可能易受进水地球化学影响的性能。具体地说，需要 以更低的成本和更少的浪费可靠地将铬(VI)降低到非常低的百万分之几的水平的新技术 而不是现有的物理或化学处理技术。 该项目试图通过材料科学和细菌还原剂的新组合来解决这一需求 动弹不得。与传统的物理或化学技术不同，这种新技术不 产生危险的二次废物流。此外，建议的技术提供了独特的氧化还原灵活性， 这使得它即使在水文地质特征可能发生变化的情况下也能保持有效。这些和其他 优点有助于将拟议的技术定位为一种高效的异位或原位治疗方法 实现水中低浓度的铬(VI)。 在拟议的项目中，通过综合动力学方法开发了所提议的技术的原型。 在全基因组转录研究的支持下，在各种操作条件下的研究。除了……之外 为处理系统开发最佳参数，该项目还将提供对独特的 用于实现铬(VI)的还原固定的生理学。材料复合材料的发展 部署高密度的目标培养以迭代的方式进行，最终选择一个组合 在连续流动反应堆研究中使用人工和实际污染的地下水进行评估。 该项目的成果将是一项新技术的概念验证，以实现高效、环境友好、 和经济高效的铬(VI)治疗。因此，这个项目具有重大的承诺，将提供一个关键的 保护和修复饮用水供应免受铬污染的必要工具，因此 促进公共安全和环境健康。

Project Summary / Abstract Hexavalent chromium, or Cr(VI), is among the most widespread contaminants in water resources in the U.S. and around the world. Cr(VI) has been found in at least 1,127 of the 1,699 current or former National Priority List (NPL) sites, which have been identified by the U.S. Environmental Protection Agency (EPA) as the most serious hazardous waste sites in the nation and are the highest priority targets for long-term federal cleanup activities. Toxicological research has found that high concentrations of Cr(VI) can contribute to stomach cancers, kidney and liver damage, and reproductive harm. As a result, there is significant demand among water providers and managers of Superfund sites for innovative technologies to address Cr(VI) contamination in a cost-effective and environmentally sustainable manner. The lack of cost-effective technologies to reduce Cr(VI) levels in water are due to technical challenges associated with existing physical/chemical approaches, including high cost, the need for disposal of secondary waste streams, and performance that can be vulnerable to influent water geochemistry. Specifically, there is a need for new technologies to reliably reduce Cr(VI) to very low parts-per-billion levels with lower costs and less waste than existing physical or chemical treatment technologies. This project seeks to address this need through a novel combination of materials science and bacterial reductive immobilization. In contrast to conventional physical or chemical technologies, this new technology does not produce a hazardous secondary waste stream. Moreover, the proposed technology offers unique redox flexibility, which allows it to remain effective even while hydrogeological characteristics may change. These and other advantages help position the proposed technology as a highly effective ex-situ or in-situ treatment approach to achieve low concentrations of Cr(VI) in water. In the proposed project, a prototype of the proposed technology is developed through comprehensive kinetic studies under various operating conditions supported by whole-genome transcriptional studies. In addition to developing optimum parameters for the treatment system, the project will also provide insights into the unique physiology employed to achieve reductive immobilization of Cr(VI). Development of material composites to deploy a high density of the targeted culture proceeds in an iterative manner to ultimately select one composite to evaluate in a continuous-flow reactor study using both synthetic and actual contaminated groundwater. The outcome of this project will be the proof-of-concept of a new technology for efficient, environmentally friendly, and cost-effective Cr(VI) treatment. As a result, this project holds significant promise to provide a critically necessary tool for protecting and remediating drinking water supplies from chromium contamination, thus promoting public safety and environmental health.