SusChEM: Non-precious metal substitution into hydrogenation metal alloy catalysts deposited onto redox active supports for facile nitrate destruction in drinking water

美国公司每年花费近30亿美元购买和制造还原催化剂，以帮助生产燃料，肥料和药物。鉴于这种投资和已证明的成功，这些催化剂不用于生产饮用水可能令人惊讶。相反，目前的饮用水处理方法成本高昂，并有可能损害环境。还原催化剂不用于清洁水的主要原因是因为它们是由贵金属制成的，成本也很高，而水是一种低价值产品。 这项工作的研究目标是通过用廉价的金属还原催化剂取代贵金属来推进水处理科学，以最低的成本和对环境的危害最小的方式实现处理目标。这些催化剂将用于处理硝酸盐，硝酸盐是世界上最常见的地下水污染物，主要来自农业肥料。 学生研究人员将接受培训，成为该技术的未来领导者，因此他们可以培训其他人设计更有效的水处理厂。拟议工作的主要目标是推进支持金属合金催化科学，用于处理无处不在的水污染物硝酸盐。具体目标是：1）开发新的金属合金纳米颗粒催化剂，具有显着更高的催化活性，用于硝酸盐还原; 2）确定电子活性载体，提高催化活性和稳定性的合金金属纳米颗粒的水处理;和3）使用生命周期评估新催化剂的环境影响和成本。为了解决这些问题，一套铂族金属为基础的合金纳米粒子与晶格取代的半和非贵金属将使用一种新的微波辅助方法合成。催化剂将负载在一系列氧化还原活性载体上，并使用先进的显微镜/光谱技术进行表征。新的催化剂将进行评估与/不修改铟硝酸盐和亚硝酸盐还原动力学，和氨的选择性。 将结果与催化剂性质进行比较，并用密度泛函理论进行解释，以确定控制机制。将在实际水处理条件下评价催化剂的长期稳定性，并将结果用于进行经济和环境生命周期评估。 本论文的工作将为以下方面提供新的基础知识：1）氢化惰性金属对催化的影响; 2）氧化还原活性载体对合金金属合金纳米颗粒活性和稳定性的影响;和3）定量评估金属合金对饮用水催化处理的成本和可持续性的影响。该奖项反映了NSF的法定使命，并被认为值得支持通过使用基金会的知识价值和更广泛的影响审查标准进行评估。

United States companies spend almost $3 billion a year buying and making reduction catalysts to help create fuel, fertilizers, and medicines. Given this investment and proven success, it is perhaps surprising that these catalysts are not used to produce potable drinking water. Instead, current drinking water treatment methods are costly and have potential to harm the environment. The main reason reduction catalysts are not used to clean water is because they are made from precious metals that also have a high cost, and water is a low value product. The research goal of this work is to advance the science of water treatment by replacing precious metals with inexpensive metal reduction catalysts to achieve treatment goals at the lowest cost and with the least harm to the environment. The catalysts will be used to treat nitrate, the most common groundwater pollutant in the world that results primarily from agricultural fertilizer. Student researchers will be trained to become future leaders in this technology, so they can train others to design more effective water treatment plants.The primary goal of the proposed work is to advance the science of supported metal-alloy catalysis for the treatment of the ubiquitous water pollutant nitrate. The specific objectives are to 1) develop new metal alloy nanoparticle catalysts with markedly higher catalytic activity for nitrate reduction; 2) identify electronically active supports that enhance catalytic activity and stability of alloy metal nanoparticles for water treatment; and 3) evaluate the environmental impacts and costs of the new catalysts using life cycle assessment. To address these objectives, a suite of platinum group metal-based alloy nanoparticles with lattice substituted semi- and non-precious metals will be synthesized using a novel microwave-assisted method. The catalysts will be supported on a series of redox active supports and characterized using advanced microscopic/spectroscopic techniques. The new catalysts will be evaluated with/without amended indium for nitrate and nitrite reduction kinetics, and selectivity for ammonia. The results will be compared to catalyst properties and interpreted with density functional theory to identify controlling mechanisms. Long-term catalyst stability will be evaluated under realistic water treatment conditions, and the results used to perform economic and environmental life cycle assessments. The proposed work will result in new fundamental knowledge regarding 1) the effects of hydrogenation-inactive metals on catalysis; 2) the influence of redox active supports on alloy metal alloy nanoparticle activity and stability; and 3) a quantitative assessment of the effects of metal alloys on cost and sustainability of catalytic treatment of drinking water.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.