多孔生物质炭/Z型三元TiO2异质结光催化剂的构筑及去除EDCs的机理研究

The hydrophobic endocrine disrupting chemicals (EDCs) with high toxicity in low concentration cause adverse effects on human health and environment, which has become a hotspot issue and difficulty in environmental pollution control. In this project, we propose a new idea that this type of pollutants can be removed by non-polar adsorption and polar degradation and the inhibitory effect of hydrophilic natural organic matter on performance of prepared materials will be eliminated or reduced in complex water matrices. Different types of wood tissues will be utilized to prepare biochar/TiO2 composites via one-step method, based on that, the proper semiconductors with narrow energy band will be introduced and combined with heterojuction of anatase and rutile to form porous biochar/Z-scheme ternary TiO2 heterostructured photocatalysts. The porous biochar with hydrophobic nature preferentially will adsorb the target pollutants coexisted with hydrophilic natural organic matters via π-π interaction strong, which opens the highway that the target pollutants transfer from water body to adsorption sites, and to the decomposition center of photocatalysts, and then the target pollutants will be decomposed polarly by Z-scheme ternary heterostructured photocatalysts with high photocatalytic activity and visible-light response. The relationship between structure and the performance of prepared materials, the degradation mechanism and removal mechanism of target contaminants and estrogenic activity of decomposition intermediates will be investigated to assess possible environmental risk. Research in this project would have significant theoretical value and good application prospect for the removal of other emerging pollutants.

环境中低浓度、高毒性和疏水性内分泌干扰物对人类健康和生态环境带来极大危害，已成为环境治理的热点和难点。本项目拟提出非极性吸附和极性光催化降解的新思路有效去除实际水体中这类污染物，减少或消除共存的极性天然有机质的抑制。拟用不同木质组织为生物质炭源兼作生物模板，一步仿生制备多孔生物质炭/TiO2复合材料，在此基础上，选择合适的窄禁带半导体与锐钛矿/金红石异质结复合，制备多孔生物质炭/Z型三元TiO2异质结光催化剂，利用疏水性多孔生物质炭组分通过π-π作用力优先吸附与大量极性天然有机质共存的目标污染物，打开目标污染物从水相-吸附位点-催化位点的快速迁移通道，再利用高效、可见光响应的Z型三元异质结光催化剂的活性位点，实现极性降解。考察材料结构与性能之间的关系，研究降解机理、目标污染物的去除机制和降解中间体的雌激素活性，探明环境风险，为其它新型有机污染物的治理提供可能的途径。

环境中低浓度、高毒性和疏水性内分泌干扰物对人类健康和生态环境带来极大危害，已成为环境治理的热点和难点。按照项目计划，首先制备了一系列窄禁带半导体/二氧化钛光催化异质结复合材料，再用模板法制备了4种不同孔径活性炭/二氧化钛，在此基础上，进一步制备了2种多孔炭/二氧化钛/BiOI复合光催化剂异质结。其次，把所制材料用于吸附/可见光催化降解协同去除雌激素效应最强的17ɑ-乙炔基雌二醇（EE2），提出降解机理。最后，考察极性天然有机质和无机离子对其催化性能的影响，以及在实际水体中去除效果，检测降解中间体和产物的雌激素活性。结果表明，多孔炭/二氧化钛异质结催化剂基本消除了实际水体中有机质和离子的抑制，不产生具有雌激素活性的中间体，其在实际水体中显示出潜在的应用前景。