Exploration of the Mechanisms Controlling Emulsion-Based Alkalinity Release during Subsurface Remediation

修正物的控制传递和释放是改善地下修复背后的科学和工程的重要概念。目前管理地下水污染的许多方法依赖于在补剂输送方面的进一步进展，以启动和维持污染物的降解或固定化。π吗?S的研究整合了多个尺度的实验室实验，以更好地了解工程师如何在受污染的地下环境中控制修复修正的位置和通量。本项目的重点是利用水包油乳液来增加碱度。利用耦合的物理、化学和生物过程对污染场地进行补救和管理的兴趣，往往需要在处理期间和在某些情况下，在处理后很长时间内控制pH值。本研究的中心假设是，水包油乳液可以有效地调节修复过程中的碱度释放。本项目旨在阐明控制含有纳米或亚微米大小的碳酸盐和金属氧化物颗粒的水包油乳液中碱性释放的机制。项目目标是：(i)评估控制豆油颗粒稳定性的机制；（ii）创建和优化在分散豆油相中含有碱性释放颗粒的乳剂；（三）阐明豆油成分对碱度释放速度的影响；（iv）分析水包油乳剂输送和释放碱度以控制地下水pH值的能力。将开发和部署与过滤理论和地下pH值调整相关的模型引出活动，以激励和吸引学习者参与塔夫茨大学土木工程课程的地球环境工程主题。PI致力于与塔夫茨大学STEM多样性中心（一个协调塔夫茨大学所有STEM多样性工作的伞型组织）合作，以加强研究和学习环境的多样性。项目结果将广泛传播给学生和研究人员。

Controlled delivery and release of amendments is an important concept for improving the science and engineering behind subsurface remediation. Many current approaches to managing groundwater contamination rely on further advances in amendment delivery to initiate and sustain contaminant degradation or immobilization. The PI?s research integrates laboratory experiments across multiple scales to better understand how engineers can control the placement and flux of remedial amendments within the contaminated subsurface environment. Emphasis in this project is placed on the addition of alkalinity using oil-in-water emulsions. Interest in harnessing coupled physical, chemical and biological processes for remediation and stewardship of contaminated sites often necessitates control of pH during treatment and, in some cases, long thereafter. The central hypothesis of this research is that oil-in-water emulsions can be effective tools for modulating alkalinity release during remediation. This project aims to elucidate the mechanisms that control alkalinity release from oil-in-water emulsions designed to contain nano- or submicron-size carbonate and metal oxide particles. Project objectives are: (i) assess mechanisms controlling particle stability within soybean oil; (ii) create and optimize emulsions containing alkalinity release particles within a dispersed soybean oil phase; (iii) elucidate the influence of soybean oil composition on the rate of alkalinity release; and (iv) analyze the ability of oil-in-water emulsions to deliver and release alkalinity for control of groundwater pH. Model Eliciting Activities related to filtration theory and subsurface pH adjustment will be developed and deployed to motivate and engage learners in the geoenvironmental engineering thread of the civil engineering curriculum at Tufts. The PI is committed working with Tufts Center for STEM Diversity - an umbrella organization that coordinates all STEM diversity efforts at Tufts University - to enhance diversity within research and learning environments. Project results will be disseminated to a broad spectrum of students and researchers.