煤基碳气凝胶的结构设计、可控制备与应用基础研究

Aiming at the low-carbon and high value-added utilization of the coal resources from Shanxi province and environmental protection, this proposal constructs macroscopic coal-based carbon materials with novel nanostructure and unique properties by using coal molecular tailoring and step conversion strategies, applying in the field of deep purification of coking waste water. The small molecule organic compounds in coal are taken as carbon source to prepare onion-like carbon by microwave-assisted solvothermal method; the graphite crystallites in coal are used as precursor to prepare coal-based graphene through oxidation stripping method; and the self-supported coal-based monolithic carbon aerogels are controllably assembled from onion-like carbon and coal-based graphene by wet chemistry. Molecular recognition and heteroatomic doping methods are adopted to realize the resource recovering and harmless removal of orgagic pollutants in coking waste water by the carbon aerogel-based molecularly imprinted material and 3D electrocatalytical oxidation electrode, respectively. The surface chemistry and porosity evolution during the application of the materials are investigated, so as to elucidate the relationship between coal-based aerogel structure and its molecular recognition and electrocatalytic oxidation performance. The implementation of this project will forge the preparation theory and technology of coal-based functionalized carbon aerogel, as well as the theoretical guidance and technological support for the green and high value-added utilization of coal resources in Shanxi province.

针对山西丰富煤炭资源的低碳高附加值利用和环境保护，申请项目采用煤的分子裁剪和分级转化策略，构筑具有新颖纳米结构和独特性能的煤基宏观碳材料并用于焦化废水深度净化。以煤中小分子有机物为碳源，微波辅助溶剂热法制备洋葱碳；以煤中石墨微晶为前驱体，氧化剥离法制备煤基石墨烯。通过表面化学性质调控，实现洋葱碳和石墨烯片的可控组装，获得煤基碳气凝胶自支撑宏观体结构。采用分子识别和杂原子掺杂技术，以碳气凝胶构筑煤基分子印迹块体材料和电催化氧化三维电极，实现焦化废水中有机污染物的资源化回收和无害化脱除，研究材料使用过程中表面化学性质和孔隙结构演变规律，揭示煤基碳气凝胶结构与分子识别和电化学催化氧化性能之间的构效关系。项目的实施将形成煤基功能化碳气凝胶的制备理论和技术，为山西煤炭资源绿色高值利用提供理论指导和技术支持。

本项目针对山西丰富煤炭资源的低碳高附加值利用和环境保护需求，围绕煤基纳米碳球、石墨烯及碳气凝胶的结构设计、可控制备和功能化应用展开研究，取得的主要进展如下：1）以脂肪性和芳香性煤基小分子为碳源，实现碳量子点以及多种结构和特性的煤基纳米碳球的可控制备；2）以不同变质程度的山西煤为碳源，探究煤中微晶石墨结晶程度与石墨烯产物结构之间的关联，制备了大小、层数、表面官能度和缺陷度可调控的煤基石墨烯；3）通过液相自组装构筑了超轻（4.56 mg cm-3）、高弹性（高达95%的压缩率）、高比表面积（787.92 m2 g-1）、高导电性和优良表面反应性的煤基三维梯级孔结构复合气凝胶；4）设计并制备负载FeOOH的煤基电催化氧化三维材料，并建立了石墨烯组装体光热转化材料，实现焦化废水有机污染物氧化降解；5）设计并制备了一系列煤基碳纳米球基与煤基碳气凝胶基分子/离子印迹材料，实现了对焦化废水中苯酚（106.23 mg g-1）、喹啉（131.22 mg g-1）等杂原子芳烃以及对重金属铜离子（45.46 mg g-1）以及粉煤灰中锂离子（57.67 mg g-1）等的选择性优先识别与深度分离。本项目的研究成果为煤基碳材料应用于焦化废水中杂原子芳烃的资源化回收和无害化处理，为山西煤炭资源绿色高值利用提供了充分的理论基础和实践经验。