Diephuis William R, Molloy Anna L, Boltz Lindsey L, Porter Tristan B, Aragon Orozco Anthony, Duron Reina, Crespo Destiny, George Luke J, Reiffer Andrew D, Escalera Gabriela, Bohloul Arash, Avendano Carolina, Colvin Vicki L, Gonzalez-Pech Natalia I
Department of Chemistry, Hope College, Holland, MI 49423, USA.
Department of Chemistry, Rice University, Houston, TX 77005, USA.
Nanomaterials (Basel). 2022 May 9;12(9):1598. doi: 10.3390/nano12091598.
The presence of arsenic in groundwater and other drinking water sources presents a notable public health concern. Although the utilization of iron oxide nanomaterials as arsenic adsorbents has shown promising results in batch experiments, few have succeeded in using nanomaterials in filter setups. In this study, the performance of nanomaterials, supported on sand, was first compared for arsenic adsorption by conducting continuous flow experiments. Iron oxide nanoparticles (IONPs) were prepared with different synthetic methodologies to control the degree of agglomeration. IONPs were prepared by thermal decomposition or coprecipitation and compared with commercially available IONPs. Electron microscopy was used to characterize the degree of agglomeration of the pristine materials after deposition onto the sand. The column experiments showed that IONPs that presented less agglomeration and were well dispersed over the sand had a tendency to be released during water treatment. To overcome this implementation challenge, we proposed the use of clusters of iron oxide nanoparticles (cIONPs), synthesized by a solvothermal methodology, which was explored. An isotherm experiment was also conducted to determine the arsenic adsorption capacities of the iron oxide nanomaterials. cIONPs showed higher adsorption capacities (121.4 mg/g) than the other IONPs (11.1, 6.6, and 0.6 mg/g for thermal decomposition, coprecipitation, and commercially available IONPs, respectively), without the implementation issues presented by IONPs. Our results show that the use of clusters of nanoparticles of other compositions opens up the possibilities for multiple water remediation applications.
地下水中以及其他饮用水源中砷的存在引发了显著的公共卫生问题。尽管在批量实验中，利用氧化铁纳米材料作为砷吸附剂已显示出有前景的结果，但很少有研究成功地在过滤装置中使用纳米材料。在本研究中，首先通过进行连续流实验，比较了负载在沙子上的纳米材料对砷的吸附性能。采用不同的合成方法制备氧化铁纳米颗粒（IONPs）以控制团聚程度。通过热分解或共沉淀法制备IONPs，并与市售IONPs进行比较。利用电子显微镜对沉积在沙子上的原始材料的团聚程度进行表征。柱实验表明，团聚较少且在沙子上分散良好的IONPs在水处理过程中容易释放出来。为克服这一应用挑战，我们提出使用通过溶剂热法合成的氧化铁纳米颗粒簇（cIONPs），并对其进行了探索。还进行了等温线实验以确定氧化铁纳米材料对砷的吸附容量。cIONPs显示出比其他IONPs更高的吸附容量（121.4 mg/g，而热分解法、共沉淀法和市售IONPs的吸附容量分别为11.1、6.6和0.6 mg/g），且不存在IONPs所呈现的应用问题。我们的结果表明，使用其他组成的纳米颗粒簇为多种水修复应用开辟了可能性。
