去除水中有机磷阻燃剂的吸附机理及其高效吸附-降解的技术原理研究

Organic phosphorus flame retardants (OPFRs) as emerging contaminants have high solubility in water, and they widely exist in global waters and affect the human health and biological security. Since the removal of OPFRs from waters has not been reported in the world, the efficiency of common adsorbents and their adsorption mechanism are unknown. In this study, the adsorption behavior of typical OPFRs on the conventional adsorbents will be investigated, and the role of phosphorus-containing groups will be clarified. The adsorption mechanism of OPFRs on different materials will be elucidated from the molecular level. Based on the known sorption mechanism, the efficient magnetic 3D-reduced graphene oxide (3D-rGO) will be prepared with high adsorption rate and high adsorption capacity for the chlorinated OPFRs. The regeneration of the spent 3D-rGO will be studied. According to the special property of magnetic components and graphene oxide, some techniques such as the electric Fenton and Fenton-like oxidation as well as zero-valent iron reduction will be used to completely degrade chlorinated OPFRs and fully recover the adsorbent for the stable reuse. Finally, the technical principle of magnetic 3D-rGO regeneration and complete degradation OPFRs simultaneously will be proposed. This study can provide the theoretical and technical support for the environmental process and contamination control of OPFRs in waters, helpful for the efficient removal of micro-pollutants such as OPFRs in water and wastewater treatment.

新兴污染物有机磷阻燃剂（OPFRs）在水中溶解度大，在全球的水环境中普遍存在，直接危害人类健康和生物安全。国际上还没有开展吸附去除水中的OPFRs 的研究，常规吸附剂的有效性和吸附机理还不清楚。本项目拟系统研究常用吸附剂对典型OPFRs的吸附特性，弄清含磷基团在吸附中的作用，从分子水平阐明OPFRs在不同材料上的吸附机理；据此构建适合吸附去除氯代OPFRs的高效磁性三维还原氧化石墨烯（3D-rGO）材料，以期具有吸附量高、吸附速度快等特点；研究突破3D-rGO材料的再生方法，利用负载的磁性组分和石墨烯的特性，通过电芬顿、类芬顿氧化以及零价铁还原等方法，实现氯代OPFRs的完全降解、吸附材料可稳定重复使用的目标，进而提出磁性3D-rGO再生同时完全降解OPFRs的技术原理。本研究能为水中OPFRs的环境过程和污染控制提供理论和技术支持，有助于在给水和污水处理中高效去除OPFRs类微量污染物。

有机磷阻燃剂（OPFRs）污染水环境是近年来全球关注的热点问题，但有关其从水中吸附去除报道较少。本研究系统阐明了不同OPFRs在传统活性炭和树脂上的吸附特性和吸附机理，并通过精确调控共价有机骨架材料（COFs）结构，阐明了材料孔径与吸附性能的关系。研究进一步制备了磁性的粉末碳材料（PC/Fe3O4）和块状磁性还原氧化石墨烯（3DrGO），研究了其吸附和降解典型氯代OPFRs的特性和机理。.粒子内扩散限速模型适用OPFRs在传统多孔材料上的吸附过程。小粒径，适宜孔径和相对疏水性表面的吸附剂有利于OPFRs快速有效吸附。粉末活性炭（PAC）由于更多暴露的吸附位点比GAC具有更强的吸附能力。氧化GAC（O-GAC）和XAD7hP树脂等相对亲水的吸附剂比疏水的GAC和XAD4树脂等具有更低的吸附量。小孔径的COFs会阻止OPFR分子进入孔中，导致吸附量低，而相对大孔径的COFs会降低吸附能，也不利于COFs对OPFR的吸附。研究通过对比实验和统计分析，表明多孔材料对OPFRs的吸附机理包括疏水、静电、氢键、和π-π作用等。通过机械球磨法和水热共沉淀的方法均能成功在碳基材料上负载磁性纳米Fe3O4，所制备的PC/Fe3O4和3DrGO均能在Fenton体系下有效降解氯代OPFRs，优于活化PMS体系。通过DFT计算和LCMS分析，氯代OPFRs上P-O键不稳定且容易在Fenton体系中断开，产生小分子卤代烃；OPFRs也容易在Fenton体系下进行脱氯反应，逐步形成烷烃类次级产物。.本研究能系统认识新兴污染物OPFRs在固液界面的吸附和转化规律，为高效去除水中OPFRs提供理论和技术指导。本项目发表SCI论文4篇，参加学术会议4次。