Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of Environments, University of South Australia, Mawson Lakes, SA 5095, Australia.
Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of Environments, University of South Australia, Mawson Lakes, SA 5095, Australia.
J Hazard Mater. 2015 Oct 15;296:37-45. doi: 10.1016/j.jhazmat.2015.04.027. Epub 2015 Apr 13.
Biomolecules taken from plant extracts have often been used in the single-step synthesis of iron-based nanoparticles (Fe NPs) due to their low cost, environmental safety and sustainable properties. However, the composition of Fe NPs and the degradation mechanism of organic contaminants by them are limited because these are linked to the reactivity of Fe NPs. In this study, Fe NPs synthesized by grape leaf extract served to remove Orange II. Batch experiments showed that more than 92% of Orange II was removed by Fe NPs at high temperature based on adsorption and reduction and confirmed by kinetic studies. To understand the role of Fe NPs in the removal process of azo dye, surface analysis via X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) were employed, showing that the Fe NPs were composed of biomolecules, hydrous iron oxides and Fe(0), thus providing evidence for the adsorption of Orange II onto hydrous iron oxides and its reduction by Fe(0). Degraded products such as 2-naphthol were identified using LC-MS analysis. A degradation mechanism based on asymmetrical azo bond cleavage for the removal of Orange II was proposed.
由于成本低、环境安全和可持续性，植物提取物中的生物分子常被用于一步法合成铁基纳米粒子 (Fe NPs)。然而，由于 Fe NPs 的反应性与其组成和有机污染物的降解机制有关，因此对 Fe NPs 和有机污染物的降解机制的了解有限。在这项研究中，葡萄叶提取物合成的 Fe NPs 用于去除橙色 II。批实验表明，基于吸附和还原，在高温下 Fe NPs 可去除超过 92%的橙色 II，动力学研究也证实了这一点。为了了解 Fe NPs 在偶氮染料去除过程中的作用，通过 X 射线光电子能谱 (XPS) 和透射电子显微镜 (TEM) 进行了表面分析，表明 Fe NPs 由生物分子、水合氧化铁和 Fe(0)组成，从而为橙色 II 吸附到水合氧化铁及其被 Fe(0)还原提供了证据。使用 LC-MS 分析鉴定了降解产物，如 2-萘酚。提出了一种基于不对称偶氮键断裂的橙色 II 去除降解机制。
