高岭土纳米管（片）多级功能矿物材料的构筑用于低浓度气相污染物的去除研究

This project pays attention to the gaseous pollutants with low concentration, high poisonousness and hard degradation, and focuses on the land occupation and environmental pollution caused by coal kaolin in Inner Mongolia and the whole country. On the basis of unique layered structure of coal kaolin and hierarchical construction technique, nano-metal/polyoxometalate/kaolin nanotubes (nanoplates) hierarchical functional mineral materials are designed and constructed under the guidance of density functional theory. The microstructure, electronic structure and surface as well as interface properties are adjusted through controlling the chemical compositions of polyoxometalate and the size, morphology, composition and loading amount of nano-metal particles. The influence of polyoxometalate structure and metal loading on band energy position, redox ability, light absorption efficiency and charge separation efficiency of hierarchical functional mineral materials as well as the support effects of kaolin nanotubes (nanoplates) are studied. The micro-reaction mechanism of gaseous pollutants molecules and kaolin nanotubes (nanoplates) hierarchical functional mineral materials is investigated. This project may provide a new thought for the comprehensive utilization of coal kaolin and a kind of high-performance catalysts for the removal of gaseous pollutants with low concentration, high poisonousness and hard degradation. Moreover, this project possibly contributes a new idea for designing and constructing the hierarchical functional mineral materials.

本项目针对气体环境中低浓度、高毒性、难降解污染物问题，着眼于内蒙古乃至全国因煤系高岭土带来的土地侵占和环境污染问题，基于煤系高岭土独特的层状结构，借助纳米多级构筑手段，以密度泛函理论为指导，设计组装合成纳米金属/杂多酸/高岭土纳米管（片）多级功能矿物材料。通过控制杂多酸的化学组成和结构、纳米金属颗粒的尺寸、形貌、组成及负载量等因素，调控高岭土纳米管（片）多级功能矿物材料的微观结构、电子结构及表界面特性，研究杂多酸结构调变、金属负载对多级功能矿物材料的能级位置、氧化还原能力、光吸收效率和空间电荷分离效率的影响及高岭土纳米管和纳米片的载体效应，探索气体污染物分子与高岭土纳米管（片）多级功能矿物材料的微观反应原理。该项目的实施有望为煤系高岭土的综合利用提供一种新思路，为低浓度、高毒性、难降解气相污染物的去除提供一种高性能催化剂，并为多级功能矿物材料的设计合成提供一种新想法。

煤矸石，又称煤系高岭土，是煤开采过程中的固体废弃物，其主要矿物晶相为高岭石。埃洛石是一种具有管状形貌的天然矿物，与高岭土同属于高岭石族，。本项目以煤矸石为基体，采用二甲基亚砜为插层剂得到了插层率为93%的高岭土纳米片，之后以十六烷基三甲基溴化铵为置换剂得到了高岭土纳米管。. 以煤矸石为基体构建了多个功能复合材料。在酒石酸的存在下， CG可以在20 min内实现对Cr(VI)的完全还原。以三聚氰胺和煤矸石为原料构筑了含有双缺陷的复合型催化剂C3N4-CG，该催化剂在30 min内对BPA的降解及矿化率分别能够达到90%和80%。煤矸石活化过硫酸盐(PS)实现了对抗生素盐酸四环素(TC)的高效降解。改性煤矸石实现了对Cr(VI)的有效吸附。煤矸石负载杂多酸铵(NH4-HPW/CG)实现了对阳离子型污染物的选择性去除。煤矸石表面丰富的羟基以及表面呈负电性是其提高功能复合材料催化活性和吸附特性的关键因素。. 以埃洛石为基体构建了多个功能复合材料。以埃洛石为硬模板制备一维介孔管状g-C3N4，其降解效果是普通g-C3N4的4.6倍。以埃洛石为基体构筑了In2O3/HNTs高效吸附剂，其吸附效率和吸附值分别是In2O3的7倍和10倍，是HNT的10倍。CuO/HNTs通过激活过硫酸盐(PMS)实现对双酚A(BPA)的有效去除，其TOC值可达96%，是CuO的2.2倍。xZIS-HNTs和xZIS-HNTs/Ay半导体复合催化剂在可见光照射下分解水产氢，并可将4-硝基苯酚还原为4-氨基苯酚，实现光催化制氢加氢“一体化”。埃洛石独特的天然管状结构和表面丰富的羟基是埃洛石基功能复合材料性能提升的关键。. 本项目深层挖掘了煤矸石和埃洛石在构筑功能复合材料方面扮演的重要角色，其表面丰富的羟基及微量元素在功能材料的构建以及环境治理领域起到不可估量的作用。