新型MOFs材料的制备及其对青海藏毯印染废水的处理性能研究

Tibetan carpet industry is a new and promising industry based on resource characteristic of Qinghai province. However, studies on its pollution treatment have not been reported till date, which seriously hampered the industrial development. Metal-organic frameworks (MOFs),is a new class of nanoporous materials that can quickly adsorp and/or photocatalytic degrade dyeing wastewater. But its stability and visible light response is still relatively low, limited the application of this technology, thus presenting a greater challenge in MOFs design. The present project intends to design new types of MOFs with specific configuration by using two-step modular approach which exploits preformed trigonal prisms, and then by optimizing the organic ligands configuration or designing interspersed structural to increase the material stability, by modifying the organic linker through different groups to tune the optical response of MOFs. In addition, through combination of the TiO2 photocatalysts with MOFs aims to develop Ti-MOFs. And then using these obtained materials to study their adsorption and photocatalytic degradation properties on the Qinghai Tibetan carpet wastewater treatment, including investigates the adsorption capacity of organic dyes, heavy metal ions and inorganic ions on MOFs, study their desorption properties and establish the adsorption kinetics models. Moreover, their photocatalytic performance and the influence factors will be tested, which finally helps to explore the reaction mechanism. These experiments are aiming to explore the structure-property relationship of MOFs and their optimize conditions. The work planned in the present project will provide theoretical basis for Qinghai Tibetan carpet dyeing wastewater treatment, which has great significance to achieve sustainable development of the Tibetan carpet industry and the HuangShui river environment protection.

藏毯产业是青海省充分利用资源优势而着力培育的新兴产业。关于其难处理印染污水问题，却鲜有研究报道，严重制约了产业发展。金属-有机骨架(MOFs)是一类新型染料废水处理材料,但是其稳定性和可将光响应能力还比较低，影响了该技术的推广应用。本项目以三棱柱构筑单元两步法，制备新颖构型MOFs材料。通过优化有机配体构型、设计穿插结构，增加材料稳定性；利用不同基团修饰，拓宽材料可见光响应能力；结合钛半导体光催化剂，设计制备钛基有机框架材料，并研究所得MOFs材料对藏毯印染废水的吸附和光催化处理性能。内容包括：研究材料对废水中染料分子、重金属离子和非金属离子的吸附能力；考察材料的脱附性能；建立吸附动力学模型；研究材料对废水的光催化性能；考察催化性能影响因素；探索反应机理。通过吸附动力学表征和光催化降解实验，揭示出材料的构效关系及优化条件，为实现藏毯印染废水实际处理奠定理论基础。

金属有机框架（MOFs）是一类新型的窄带隙能光催化材料。具有吸附容量大，选择性高，再生回收容易等诸多优点，可被用作为光催化剂，催化降解处理污染水体中的染料分子。.然而，将MOFs材料应用于废水处理的研究，目前还主要存在4大关键问题：1）材料的化学稳定性不够高；2）材料的可见光响应范围还比较窄；3）同钛半导体光催化技术的有机结合研究还很少；4）材料在水处理应用中的构效关系还不明确。因此，设计合成新型MOFs材料，研究其对藏毯印染废水的处理性能，探明材料催化性能的影响因素和优化方案，对于本地水体保护及产业发展，具有重要的研究意义和诱人的应用前景。 .本项目主要研究内容有：（1）基于稀土金属离子构筑多孔MOFs材料，并研究材料对染料废水的吸附和催化能力；（2）基于共轭柔性有机配体和过渡金属离子构筑多孔MOFs材料，并研究材料对染料废水的吸附和催化能力；（3）基于大共轭刚性有机配体和过渡金属离子构筑MOFs材料，并研究材料的结构特点和光吸收能力；（4）基于小分子有机配体构筑金属有机框架材料，并表征了材料的结构和催化降解染料废水的性能。（5）进行了其它一维、二维材料的制备及性质研究。成功合成得到了五个系列，29种金属有机配合物和1种 MOFs-14/量子点复合材料。其中20种材料表现出三维有机框架结构，9种材料表现出零维，一维或者二维结构特点。催化实验结果表明，所得材料对MB具有较好的催化降解效果，能被重复使用5次以上而保持催化效果基本不变。说明材料具有较好的应用前景。最后，初步探明了材料性能的影响因素，并提出了相应的优化方案。