Instituto de Investigación e Ingeniería Ambiental, and Escuela de Ciencia y Tecnología, Universidad Nacional de San Martín, Campus Miguelete 25 de Mayo y Francia, San Martín, Provincia de Buenos Aires, Argentina.
Consejo Nacional de Investigaciones Científicas y Técnicas, Rivadavia, 1917, Buenos Aires, Argentina.
Environ Sci Pollut Res Int. 2018 Aug;25(22):21368-21384. doi: 10.1007/s11356-017-0484-2. Epub 2017 Oct 31.
In this work, we report on the structural and textural changes in fluvial sediments from Reconquista River´s basin, Argentina, due to processes of contamination with organic matter and remediation by bioleaching. The original uncontaminated matrix showed quartz and phyllosilicates as the main primary mineral constituents and phases of interstratified illite-montmorillonite as secondary minerals. It was found that in contaminated sediments, the presence of organic matter in high concentration causes changes in the specific surface area, particle size distribution, size and distribution of micro and meso, and the morphology of the particles with respect to the uncontaminated sediment. After the bioleaching process, there were even greater changes in these parameters at the level of secondary mineral formation and the appearance of nanoparticles, which were confirmed by SEM. Especially, we found the formation of cementing substances such as gypsum, promoting the formation of macroporous aggregates and the weathering of clay components. Our results indicate that the bioleaching not only decreases the content of metals but also favors the formation of a material with improved characteristics for potential future applications.
在这项工作中，我们报告了阿根廷雷孔基斯塔河盆地河流沉积物由于有机物污染和生物浸出修复过程而发生的结构和质地变化。原始未受污染的基质显示出石英和层状硅酸盐作为主要的原生矿物成分，以及层间伊利石-蒙脱石作为次生矿物。研究发现，在受污染的沉积物中，高浓度有机物的存在会导致比表面积、颗粒尺寸分布、微尺寸和中尺寸的大小和分布以及颗粒形态相对于未受污染的沉积物发生变化。生物浸出后，在次生矿物形成和纳米颗粒出现的水平上，这些参数甚至发生了更大的变化，这一点通过 SEM 得到了证实。特别是，我们发现了石膏等胶结物质的形成，促进了大孔团聚体的形成和粘土成分的风化。我们的结果表明，生物浸出不仅降低了金属含量，而且有利于形成具有潜在未来应用的改进特性的材料。
