GOALI: Cationic Inorganic Materials for Perchlorate Remediation

[1603754]高氯酸橄榄离子是一种高流动性的天然水体，很难处理。由于其相似的分子大小，它会阻碍甲状腺对碘的吸收，并会破坏正常生长、代谢和发育所需激素的产生能力，被认为是内分泌干扰物，对儿童和孕妇尤其危险。这项GOALI提案将在加州大学圣克鲁斯分校的PI小组和Aerojet Rocketdyne之间建立重要的合作关系。该项目将研究一种处理高氯酸盐污染的水的新方法，并产生比目前的单一使用方法更有效、更经济的高氯酸盐修复方法。PI发现了slg -n阳离子材料，它可以在无限循环中将硝酸盐交换为高氯酸盐。这一重要进展可能会取代Aerojet Rocketdyne公司目前使用的一次性离子交换树脂。Aerojet Rocketdyne工地的地下水中含有高达6000 ppb的高氯酸盐。加州高氯酸盐的最大污染物水平（MCL）为4ppb，而EPA规定硝酸盐的MCL为10ppm。因此，6 ppm的硝酸盐释放量是可以接受的。然而，PIs实验室最近的一项突破是用醋酸盐代替硝酸盐，这对环境无害。通过将固体放入含有进入的阴离子的溶液中，阴离子很容易交换。该工艺比广泛研究的离子交换树脂层状和双氢氧化物具有更强的选择性、快速和更高的容量。SLUG-n固体可以无限重复使用（进行了7次循环，作为概念验证）。研究将集中在几个方面：(1)阴离子交换化学的研究：当前材料的交换容量、动力学和循环寿命的表征和优化。竞争阴离子，如硫酸盐，硝酸盐和碳酸盐将被引入远高于污染地下水的典型水平，以验证高氯酸盐的选择性；（ii）在公司进行试点测试？地下水提取和处理设施：最有前途的高氯酸盐交换器将在Aerojet Rocketdynes处理设施的侧流中进行研究。批和柱测试将并行进行，并由现场专家进行日常监控。流动柱将被材料填充，由于主体材料可以在室温下以99%的收率合成，因此合成的放大将是直接的；（iii）改进阴离子交换剂的设计：模板阴离子、有机连接剂和宿主材料的金属构件将会改变，以隔离具有改进交换性能的结构，降低成本，降低传出阴离子的毒性，并可能针对其他阴离子污染物。Aerojet Rocketdyne有兴趣与加州大学圣克鲁斯分校合作，推进创新技术，提高捕获和处理受污染地下水中高氯酸盐的能力。公司将为学生提供实践经验，这些学生的职业道路将继承并朝着长期治疗目标取得重大进展。位于Aerojet Rocketdyne萨克拉门托基地的高度安全的地下水提取和处理设施将为这些有前途的新材料提供侧流和日常测试监测。Aerojet Rocketdyne拥有专业知识和基础设施，可以帮助指导研究，并在这项为期三年的GOALI研究显示商业可行性潜力时为商业化提供帮助。除高氯酸盐外，开发铬酸盐和砷酸盐等处理氧阴离子的新材料是实现更有效、更低成本的修复和水处理目标的重要一步。

1603754OliverPerchlorate ion is highly mobile natural waters and is difficult to treat. Due to its similar molecular size, it blocks the uptake of iodine by the thyroid gland and can disrupt the ability to produce hormones needed for normal growth, metabolism and development, and, is considered an endocrine disrupter, especially dangerous to children and pregnant women. This GOALI proposal will establish an important collaboration between the PI's group at UC Santa Cruz and Aerojet Rocketdyne. The project will examine a new approach to treating perchlorate contaminated waters and result in a more effective, economical perchlorate remediation than the current single-use processes.The PI has discovered SLUG-n cationic materials that can exchange nitrate for perchlorate over indefinite cycles. This important advance could lead to the replacement of the single-use ion exchange resins currently used at Aerojet Rocketdyne. The groundwater plume at the Aerojet Rocketdyne site has perchlorate at levels up to 6,000 ppb. The Maximum Contaminant Level (MCL) for perchlorate in California is 4 ppb while the EPA mandates a nitrate MCL of 10 ppm. Release of nitrate is therefore acceptable at 6 ppm. However, a recent breakthrough in the PIs laboratory has been to replace nitrate by acetate, which is environmentally benign. The anions are easily swapped by placing the solid into a solution containing the incoming anion. The process is far more selective, rapid and higher capacity than the extensively studied ion exchange resins layered and double hydroxides. The SLUG-n solids can be reused indefinitely (seven cycles performed as proof-of-concept). The research will focus on several aims: (i) investigation of the anion exchange chemistry: characterization and optimization of the exchange capacity, kinetics and cycling lifetime for the current materials. Competing anions such as sulfate, nitrate and carbonate will be introduced way above the levels typical of the contaminated groundwater to verify the selectivity for perchlorate; (ii) pilot testing at the company?s Groundwater Extraction and Treatment facilities: the most promising perchlorate exchangers will be studied at Aerojet Rocketdynes treatment facility side streams. Both batch and column testing will be conducted in parallel and monitored daily by field specialists. Flow columns will be packed with material and scaling up of the synthesis will be straightforward since the host materials can be synthesized with 99% yield at room temperature; (iii) design of improved anion exchangers: the templating anion, organic linkers and metal building block of the host materials will be varied for isolating structures with improved exchange properties, reduced cost, lower toxicity of the outgoing anion and possible targeting of other anionic pollutants. Aerojet Rocketdyne is interested in partnering with UC Santa Cruz to advance innovative technologies that will improve the ability to capture and treat perchlorate in contaminated groundwater. The company will provide practical experience to students whose career paths will inherit and make significant advance towards a long-term treatment goal. The Groundwater Extraction and Treatment facilities under high security at the Aerojet Rocketdyne Sacramento site will provide a side stream and daily test monitoring of these promising new materials. Aerojet Rocketdyne has the expertise and infrastructure to help guide the research and aid in commercialization when this three-year GOALI study demonstrates the potential of commercial viability. The development of new materials for treatment of oxyanion including chromate and arsenate, in addition to perchlorate, is an important step in achieving remediation and water treatment goals more effectively and at lower cost.