有机污染土壤的纳米材料-微生物联合修复技术研究

With the economic growth and industrial restructuring, there have been increasing amounts of abandoned sites and obsolete buildings called "brownfield" in some urban districts of China. Some of these lands are contaminated by high concentration of hazardous organic pollutants and have the potential to threat the ecological environments and human beings，which require to be remediated before they are reused. The use of nanomaterials to degrade a range of environmental contaminants has gained increasing amounts of attention in recent years, primarily due to its larger range of application options and high degrees of reactivity. In this research, we are intended to use iron nanoparticles and degrading microorganisms for the remediation of organic contaminated soil. The nanomaterials-microorganisms combined remediation system will be constructed to investigate the effects, function and relationships of the nanomaterials-microorganisms system in the soil remediation processes. The impact of the nanomaterials-microorganisms combined remediation on the soil characteristics will be further assessed.

随着城市布局调整，很多化工、农药、石油加工企业被搬出市区，遗留下大量有机污染土壤，不仅给人体健康和生态安全带来潜在威胁，还影响了我国的城市化进程，因此亟需对有机污染土壤进行修复。目前，国际上将纳米材料应用于有机污染土壤修复的研究刚处于起步阶段。本课题拟针对我国部分土壤被有机物严重污染的现实情况，将纳米铁修复材料与微生物修复技术相结合，用于有机污染土壤的联合修复。通过构建适用于有机污染土壤修复的纳米铁-微生物联合修复体系，重点研究纳米铁-微生物联合修复有机污染土壤的过程与机理，开发适用于我国有机污染土壤修复的快速、高效、安全、低成本的纳米铁-微生物联合修复技术，为丰富土壤修复的理论和技术体系作出贡献。

本项目主要研究纳米铁修复材料及微生物对有机污染物的降解和修复效应，以及纳米铁-微生物对有机污染土壤的联合修复效应及环境影响。.我们进行了纳米零价铁颗粒的合成、修饰及表征，所制得的纳米零价铁颗粒物直径在80-150nm之间。然后将纳米材料应用于有机污染物的还原脱氯研究，发现纳米镁颗粒比微米镁颗粒具有更强的还原效果，并且具有在好氧条件下快速还原脱氯的能力，是一种新型的、具有巨大发展潜力新型纳米修复材料。.在微生物对有机污染物的降解及修复方面，筛选到一株具有较强降解能力的真菌菌株4-Z，通过基因测序及分析，确定该真菌为短帚霉（Scopulariopsis brevicaulis）。4-Z能够在30天内去除溶液中的菲（60%）、荧蒽（62%）、芘（64%）和苯并(a)芘（82%）。将4-Z应用到PAHs污染土壤的修复中，28天后PAHs的去除率达到77%，其中菲 (89%) 和苯并(a)芘 (75%)的去除率最高。说明4-Z在有机污染物降解及修复方面具有较好的应用前景。.纳米零价铁和微米零价铁对DDT污染土壤都有较好的还原脱氯效果，但是两者之间没有显著差异。将纳米零价铁与4-Z进行PAHs污染土壤的联合修复，促进了微生物修复的效果。