RUI: Elucidating interlayer chemistry for design of novel, nontoxic organoclays for contaminant remediation

有了这个奖项，化学系的环境化学科学项目资助了米德尔伯里学院的Molly Constanza-Robinson教授，以澄清有机粘土的化学性质，并将这种理解应用于新型无毒有机粘土的设计和表征，以有效地修复污染物。潜在的有害化学物质，包括杀虫剂和药品，通常在处理过的废水、接收流、地下水和饮用水井中检测到。使用改性粘土矿物（有机粘土）作为吸附剂是一种很有前途的从环境水中去除有害污染物的方法，但基本问题仍然存在。本研究小组利用光谱技术研究有机粘土层间化学环境的细节，以了解粘土的分子水平特性如何影响其吸附效率。除了发展基础知识和促进人类和环境健康的社会效益外，该项目还支持培训和指导不同群体的本科生进行跨学科环境化学研究，并通过相关课程为基础的实验室项目培训更多的学生。用长链烷基铵阳离子表面活性剂改性蒙脱土粘土已被广泛研究，并证明了有效吸附石油烃、酚类、硝基和氯代芳烃以及其他水中有机污染物的能力。虽然人们对有机粘土层间的污染物吸收了解很多，但尚未解决的问题阻碍了有机粘土用于污染物修复的优化。此外，用于有机粘土的传统表面活性剂的潜在毒性尚未得到解决。利用多种光谱技术、吸附等温线和其他表征工具，该项目研究了控制有机粘土层间化学环境的因素，包括其大小、结晶度和水合作用，以及这些特性如何影响有机粘土的吸附效率。然后将这种见解应用于新型、有效和无毒有机粘土的设计和表征。

With this award, the Environmental Chemical Sciences Program of the Division of Chemistry is funding Professor Molly Constanza-Robinson of Middlebury College to clarify the chemistry of organoclays and apply this understanding to the design and characterization of novel, nontoxic organoclays for effective contaminant remediation. Potentially harmful chemicals, including pesticides and pharmaceuticals, are routinely detected in treated wastewater, receiving streams, groundwater, and drinking water wells. Using modified clay mineral (organoclays) as an adsorbent represents a promising approach for removing harmful contaminants from environmental waters, but fundamental questions remain. This research team uses spectroscopic techniques to study the details of the organoclay interlayer chemical environment to understand how the molecular-level properties of the clay influence its sorption efficiency. In addition to developing fundamental knowledge and the societal benefit of promoting human and environmental health, this project supports the training and mentoring of a diverse group of undergraduates in interdisciplinary environmental chemical research and additional students through an associated course-based laboratory project.Montmorillonite clay modified with long-chain alkyl-ammonium cationic surfactants has been extensively studied and demonstrates the ability to effectively sorb petroleum hydrocarbons, phenols, nitro- and chloro-substituted aromatics, and other organic pollutants from water. Although much is known about contaminant uptake into the interlayer of organoclays, unanswered questions hinder optimization of the organoclays for use in contaminant remediation. Moreover, the potential toxicity of conventional surfactants used in organoclays has not been addressed. Using multiple spectroscopic techniques, sorption isotherms, and additional characterization tools, this project investigates factors that govern the organoclay interlayer chemical environment, including its size, crystallinity, and hydration, and how these properties influence the sorption efficiency of the organoclays. This insight is then applied to the design and characterization of novel, effective, and non-toxic organoclays.