天然含Fe(II)矿物结合多孔生物炭强化修复氯代烃污染的河道底泥及非生物脱氯机理研究

河道底泥中的氯代烃污染对水生态环境和人体健康造成严重威胁。采用天然含Fe(II)矿物结合多孔生物炭对氯代烃污染河道底泥进行原位修复具有广阔的应用前景，但目前尚无应用于实际河道底泥的报道，且相关过程和脱氯降解机理尚不清楚。因此，本项目针对湘江河道底泥中氯代烃的污染问题，拟将天然含Fe(II)矿物和多孔生物炭结合制备反应性复合材料，并利用该复合材料构建原位修复体系来强化底泥中氯代烃的脱氯降解。在考察不同修复体系结构、成分配比和环境因子对复合材料降解底泥中氯代烃影响的基础上，探究含Fe(II)矿物和生物炭的协同修复行为及对不同氯代烃的降解转化效率，阐明修复过程中氯代烃的非生物脱氯机理和降解途径。进一步分析底泥中氯代烃迁移性的变化、沉水植物和微生物群落的响应，探索能反馈评价底泥修复效果的生态安全指标。本项目有望为发展一种环境友好且成本低廉的氯代烃污染河道底泥修复新方法提供理论依据和技术参考。

The pollution of chlorinated hydrocarbons in river sediment poses a serious threat to the aquatic environment and human health. The in-situ remediation of chlorinated hydrocarbon contaminated river sediment by using natural Fe(II)-bearing minerals combined with porous biochar has showed broad application prospects, but there are no reports on real river sediments and the related processes and dechlorination degradation mechanisms remain unclear. Therefore, this project focuses on the pollution of chlorinated hydrocarbons in the sediment of the Xiangjiang River, and plans to combine natural Fe(II)-bearing minerals and porous biochar to prepare reactive composites and use the composites to construct an in-situ remediation system for the dechlorination degradation of chlorinated hydrocarbons in sediment. After the investigation of the effects of different remediation system structures, component ratios, and environmental factors on the degradation of chlorinated hydrocarbons in sediment, the synergetic remediation behavior of Fe(II)-bearing minerals and biochar and the degradation efficiency of different chlorinated hydrocarbons will be explored, and the abiotic dechlorination mechanisms and degradation pathway of chlorinated hydrocarbons in the remediation process will be clarified. Then, the changes in the mobility of chlorinated hydrocarbons in sediment and the responses of benthophytes and microbial communities will be further analyzed in order to explore possible ecological safety indicators that in turn can evaluate the remediation effects of the sediment. This project is expected to provide a theoretical basis and technical reference for the development of a new environmentally friendly and low-cost method for the remediation of river sediment contaminated with chlorinated hydrocarbons.