固定床式织物催化剂协同表面浸润性的调节促进吸附-光催化法去除VOCs机制研究

Adsorption-photocatalysis has a broad application prospect for degradation of volatile organic compounds (VOCs). However, this technology is still faced with the problems that hydrophobic VOCs are difficult to infiltrate on the surface of hydrophilic TiO2 catalysts and the contact between VOCs and solid catalysts is insufficient during gas-solid reaction. In this project, a graphene@TiO2/MOF composite textile with controllable composition, content, and size would be constructed as a photocatalyst, and the hydrophobic graphene would be used to improve the wettability of VOCs on the TiO2 surface. The influence of the infiltration of the photocatalysts on the photocatalytic degradation VOCs would be studied. The composite textile catalyst would be placed into the photoreactor perpendicular to the gas flow in the form of a fixed bed to increase the contact between photocatalysts and VOCs. The macro and micro kinetic models of the movement of VOCs in the reactor would be study. The synergies of adjusting the infiltration and using fixed bed catalysts are used to enhance the mass transfer and reaction processes of adsorption-photocatalytic degradation of VOCs, and ultimately increase the efficiency for removal of VOCs. The implementation of this project will clarify the key factors affecting the efficiency of the adsorption-photocatalytic removal of VOCs, clarify the mechanism of the catalyst adsorption capacity and surface infiltration on the photocatalytic efficiency, establish the motion model of VOCs molecules in fixed bed composite textile photocatalysts, and provide experimental support and theoretical basis for the efficient removal of indoor VOCs.

吸附-光催化法去除挥发性有机化合物(VOCs)有广阔的应用前景，但这一技术仍面临着疏水性VOCs在亲水性TiO2催化剂表面难以浸润和气-固反应过程中VOCs气体与固相催化剂接触不充分的难题。本项目拟构筑成分、含量、尺寸可控的石墨烯@TiO2/MOF复合织物作为光催化剂，利用石墨烯疏水亲油的特性改善VOCs在TiO2表面的浸润性，并研究浸润性对光催化降解VOCs反应过程的影响机制；将复合织物催化剂以固定床形式垂直于气流方向放入光反应器中，研究VOCs在反应器中运动的宏、微观动力学模型；协同固定床式催化剂与表面浸润性的调节，最终提高这一方法去除VOCs的效率。本项目的实施将会明确影响吸附-光催化法去除VOCs效率的关键因素，阐明催化剂表面浸润性对光催化效率的影响机制，建立VOCs分子在固定床式复合织物光催化剂间的运动模型，为实现室内VOCs的高效去除提供实验支持与理论依据。

本项目围绕解决吸附-光催化法去除挥发性有机化合物(VOCs)面临的疏水性VOCs在亲水性TiO2催化剂表面难以浸润和气-固反应过程中VOCs气体与固相催化剂接触不充分这两个核心难题开展工作，取得了一系列重要研究成果。如1)：基于能带工程原理、静电纺丝、水热、冷冻干燥等技术，构筑了3D/TiO2/RGO、TiO2/RGO/HKUST-1、FL-Ti3C2/BiOCl/SnO2等高活性的复合织物光催化剂，并研究了反应过程中催化剂放置量、初始浓度、空气湿度等参数，明确了影响吸附-光催化法去除VOCs效率的关键因素。2) 利用MOF材料提高了织物光催化剂的吸附效果；利用石墨烯、Ti3C2 MXene等改善VOCs在无机材料表面的浸润性，阐明了浸润性对光催化降解不同种类VOCs反应过程的影响机制；3）研究了固定床式催化剂对气-固反应中VOCs向催化剂表面传质的增益作用；协同固定床式催化剂与表面浸润性的调节，最终有效提高了这一方法去除VOCs的效率。本研究共发表高水平SCI论文11篇（第一标注），高被引用论文1篇，待发表的论文1篇，申请专利2项。项目负责人培养研究生4名，其中2名已毕业；在国内学术会议上做口头报告3次。