核壳结构Fe3O4@C粒子在UV-Fenton氧化去除VOCs过程中的吸附-催化作用

采用一步水热法制备核壳结构Fe3O4@C微米粒子,通过比表面积及孔径分析仪、X射线衍射仪、透射电子显微镜、傅里叶变换红外光谱仪等对粒子结构和形貌进行表征,并研究了粒子作为非均相催化剂在UV-Fenton氧化去除挥发性有机物(VOCs)中的作用机制.结果表明,核壳结构Fe3O4@C粒子由于包覆了孔隙状碳层而具有较强的吸附能力,可显著增加VOCs气体分子与Fenton试剂的接触几率,有助于提高VOCs的去除效率.通过计算反应速率常数及协同因子,证实在核壳结构Fe3O4@C粒子去除VOCs的过程中存在吸附-催化氧化协同作用.

Fabrication of Fe3O4@ C core-shell particles and its application in UV-Fenton oxidize removal of VOCs

ABSTRACT The solvothermal method was used to prepare Fe3O4@ C core-shell microspheres. The structure and morphology of the nanocomposite powders were characterized by X-ray diffraction, transmission electron microscopy, and Fourier transform infrared spec-troscopy, and then the particles were used as heterogeneous catalysts in the UV-Fenton removal of VOCs in gas. The results show that the Fe3O4@ C core-shell microspheres have a strong adsorption capacity for VOCs due to the outer layer of Fe3O4 being coated with a carbon layer of uniform thickness and pore structure. For sparingly soluble organic gases such as octane, the adsorption of these parti-cles could increase the total concentration of VOCs in the liquid phase. Therefore, the opportunity for the Fenton reagent to be in contact with the VOCs gas increases, causing a significant improvement in the gas removal efficiency. Moreover, the cooperation factorβ was introduced to evaluate the synergistic effects in the integrated process of the adsorption-catalytic oxidation by the core-shell struc-ture particles.