Mechnisms for adsorbent optimization of geogenic arsenic groundwater remediation

这项合作提案的主要目的是优化地下水砷处理技术。该项目旨在为国内市场寻找和优化能够有效修复的中国生产的固定床吸附器(FBA)新材料。研究取得潜在成功的基础是根据私营部门主管机构的互补的先进科学方法和专门知识开展的合作活动。基础研究计划涉及分子形态尺度方法，如EXAFS测量活动，以及表面络合建模(SCM)和分子动力学(DFT)建模。将现有但昂贵的FBA材料(德国GFH)与中国合作伙伴提出的一种新型廉价吸附材料(纳米二氧化钛)进行比较，以预测污染物穿透曲线，对于自来水厂确定和规划未来的运营成本非常重要。不幸的是，考虑到地下水中许多共因子和竞争性共存离子的复杂的拮抗和协同效应，预测FBA的生命周期还不是一件容易的事情。与快速小规模柱试验方法一起，结果将首次用于基于纳米二氧化钛吸附/吸附体系的均相表面扩散模型程序FAST的FBA生命周期预测参数。为了成功地实现这一点，光谱表面物种形成和SCM/FAST建模方法都必须合并在一起，即项目伙伴的互补专业知识必须合并在一起。如今，只有同时汇编对共污染物的固水相互作用的高级微观光谱表征(中国合作伙伴[S任务])和分子物种规模的高级表面络合模型(德国合作伙伴S任务)，才有可能在像《环境科学与技术》这样的高级别期刊上发表游离基丁酸的吸附剂表征结果。这些出版物为采用NSF-国际推荐FBA填料列表上的替代吸附介质提供了一个主要前提，以建立信任，使其在饮用水生产的自来水厂中得到更广泛的接受和使用。

The main purpose of this collaborative proposal is to optimize groundwater arsenic treatment technology. The project is aimed at identifying and optimizing new fixed bed adsorber (FBA) material of Chinese production for the national market capable of effective remediation. The basis of potential success with the research is a collaborative activity according to the complementary advanced scientific methodology and expertise of the PIs. The fundamental research plan involves molecular speciation scale approaches like EXAFS measuring campaigns and both surface complexation modeling (SCM) and molecular dynamics (DFT) modeling. A comparison between established, but expensive, FBA material (German GFH) with a new cheaper adsorbent material proposed by the Chinese partner (nano-TiO2) to predict contaminant breakthrough curves is important for waterworks to determine and plan their future operating costs. Unfortunately, prediction of FBA life cycle time is not yet a trivial task given the quite complex antagonistic and synergistic effects of many co-factors and competitive co-existing ions in groundwater. Together with the rapid small scale column test approach, the results will be used for the first time to derive at parameters for the FBA life cycle prediction based on the homogeneous surface diffusion model code FAST for the nano-TiO2 adsorbate/adsorbent system. For this to achieve in a successful manner, both a spectroscopic surface speciation and the SCM/FAST modeling approaches, i.e. both the complementary expertise of the project partners have to be merged together. Publication of the results of FBA adsorbent characterization in such high-ranking journals as Environmental Science & Technology is nowadays only possible if to compile both advanced micro-spectroscopic characterization of the solid-water interaction of the co-contaminants (the China partner¿s task) with an advanced surface complexation modelling on a molecular speciation scale (the German partner¿s task). These publications provide a major prerequisite to adopt the alternative adsorptive media on the NSF-International list of recommended FBA fillings to build trust for their wider acceptance and use in waterworks for drinking water production.