孔道限域Fenton体系的构建及降解微污染物研究

Micro-pollutants in water have low concentrations while have raised serious concerns about their adverse effects on aquatic ecology and public health. For the degradation of micro-pollutants, a problem arises from the low density of pollutants in the reaction system, which results in low contact possibility between the hydroxyl radicals and the micro-pollutants, leading to the simple quenching of radicals and consequently a low degradation rate. This project aims to design a novel pore-confined Fenton system, which not only accumulates the micro-pollutants but also reduces the scale of reaction domain with reactive pores. This design is expected to degrade the micro-pollutants effectively. This project includes the fabrication of pore materials employing the hydro-thermal method and the following characterization, the construction of the micro-environment of pores through the solution chemical means, and the investigation of the reaction mechanism within the pores. This project has fundamental and applied significance by serving to enrich the family of Fenton processes for water treatment, and to add novel approach for the treatment of micro-pollutants in water.

水中有机微污染物含量低，危害大。Fenton试剂(Fe(II)+H2O2)法降解有机物多在溶液整体范围发生反应，但微污染物浓度很低，导致oOH与污染物接触反应几率小，而简单猝灭几率高，反应效率低。本项目旨在构建孔道限域Fenton(PC-Fenton)反应体系，改变Fe(II)供给方式，将Fe(II)限制在孔道内，进而限制Fenton反应的范围，同时孔道内吸附富集污染物，增加微污染物的局部浓度，提高oOH与有机微污染物的接触几率，达到提高Fenton反应效率的目的。研究通过双模板水热法制备多孔材料，通过浸渍法将Fe(II)贮藏于多孔材料内，通过电化学方法供给H2O2，构建PC-Fenton反应体系降解邻苯二甲酸酯类有机微污染物，研究PC-Fenton反应体系的影响因素，阐明反应规律。本项目可以丰富Fenton水处理工艺的种类，为水中有机微污染物的处理提供新方法，有重要的理论价值和实际意义。

水中有机微污染物含量低，但对生态环境及公共健康危害大。Fenton反应降解微污染物在溶液整体范围发生，羟基自由基与微污染物的接触几率小，简单猝灭几率高，反应效率低。本项目以提高Fenton反应效率为目标，通过不同铁催化材料的制备，构建限域Fenton反应体系。将Fenton反应限制在材料表面进行，提升过氧化氢利用率。提出“吸附-降解-脱附”反应机制，通过对Fe催化材料Zeta电位的调控，有选择性地将有机物吸附于Fe催化材料之上，Fenton反应在材料界面上进行，反应能在中性pH条件下发生，且中性pH条件下的反应速率和酸性条件下反应速率相当。由此而衍生出的“电子效率概念”应用于零价铁修复地下水体系，另一方面，将限域Fenton反应概念拓展到E-Fenton体系，通过制备多效阴极反应材料使阴极电极同时具有吸附微量有机物及高效产H2O2的双重功能，相对于普通E-Fenton体系具更好的有机物去除效率。并基于此提出了“氧抑制”的概念，用于电化学回收二氧化碳，并将该阴极反应材料用于烟道气脱碳除硫装置。