基于铁循环调控的地下水化学氧化修复新方法

我国地下水污染日趋严重，发展绿色经济、可操作性强的地下水有机污染修复新技术迫在眉睫。原位药剂注入化学修复已成为地下水污染修复的研究热点，但面临着药剂无法精准注入和稳定传输的瓶颈问题。鉴于铁矿物广泛存在于地下水沉积物中，铁循环直接影响到碳、硫、磷等元素的循环，本项目利用现代表征技术结合密度泛函理论计算手段，研究地下水典型有机污染物分子在铁矿物不同晶面上吸/脱附和氧化还原及电子转移过程，揭示铁矿物表面铁循环机制及环境效应，进一步探讨铁循环与地下水典型有机污染物迁移转化之间非生物耦合过程以及天然小分子配体等对这些非生物耦合过程的影响，筛选出天然小分子配体有效调控地下水沉积物中天然矿物表面铁循环，进而活化氧化剂，发展基于相互不反应的氧化剂和铁循环调节剂同时注入的地下水氧化修复新方法，实现地下水中有机污染物的高效氧化降解，突破传统地下水原位注入面临的瓶颈，发展高效地下水原位注入化学氧化修复新技术。

Groundwater pollution becomes more and more serious in China, so it is urgent to develop green, economic, and easy-handling organic polluted groundwater remediation technique. Development of in-situ injection chemical oxidation methods is a hot topic in the fields of groundwater remediation, but suffers from bottleneck problems of non-precise injection and instable transportation. Regarding that iron minerals widely exist in sediments of groundwater, and Fe(II)/Fe(III) redox (iron cycle) directly influences the cycles of C, N, S, and P elements, this project will utilize modern characterization techniques in combination with density of functional theory calculation to investigate the adsorption, the desorption, the redox, and electron transfer processes of typical groundwater organic pollutant molecules on the different facets of iron mineral nanocrystals, aiming to clarify the molecular mechanisms of iron cycles on the surface of iron minerals and the environmental effects of iron minerals in sediments and soils of groundwater. Next, we will check the abiotic coupling of iron cycle and the migration and transformation processes of typical groundwater organic pollutant molecules, as well as the influences of natural small molecule ligands on the abiotic coupling, and then screen out natural small molecule ligands to effectively tune iron cycle of iron minerals in sediments and soils of groundwater for the activation of oxidants, realizing the high efficient oxidation degradation of typical groundwater organic pollutants. This study will break the bottleneck problems of non-precise injection and instable transportation faced by the traditional in-situ injection chemical oxidation techniques, and develop iron cycle based in-situ injection chemical oxidation method for groundwater remediation, and then carry out field test of in-situ injection chemical oxidation within typical zones, and finally advances groundwater remediation techniques.