复合过渡金属氧化物纳滤膜微结构调控及协同催化机制研究

Petrochemical, printing and dyeing and other industries produced a large number of organic wastewater, that have brought a serious water pollution problem and restricted the sustainable development of the industries. Application of the technology integrating ceramic membrane and ozone shows a good prospect in this field, however, the separation and decomposition properties for organic matter of the membrane used in the technology is too low to satisfy the actual requirements. Thus, this proposal aims to prepare coordinated catalytic ozone functional composite transition metal oxide nanofiltration membranes to increase the utilization of ozone by enriching the organic matter and inhibit the decrease of the membrane flux by improving the catalytic performances. The proposal would focus on three parts works: (1) Adopting nanocatalyst as toughening agent to prepare the compostie transition metal oxide nanofiltion membranes, and investigate the matching behavior of the interparticle and assembled pores, and explore the membranes pore formation mechanism and precision construction method.(2) Discussing the effects of proportion of the composite transition metal oxide on the valence, crystalline phase and catalytic activity, and revealing the coordinated catalytic ozonation mechanism of the composite metal oxides. (3)Investigating the rule of the concentration polarizationon the membrane surface, further, a reaction kinetics model of the membranes would be established for the design and optimization of the catalytic fuctional membranes based on the film theory and the catalytic reaction kinetics equation, which would provide some supports for designing and exploring the composite transition metal oxide nanofiltration membranes.

陶瓷膜与臭氧化耦合技术在低浓度、难降解有机废水处理中已展现出重要的应用前景。然而，目前该技术存在的关键问题是缺乏高分离精度、高催化活性的膜材料。为此，本项目拟通过微结构调控和协同催化作用机制的研究，开发具有协同催化效应的复合过渡金属氧化物纳滤膜，借助复合过渡金属氧化物的协同催化作用抑制浓差极化造成的膜通量衰减，并利用纳滤膜浓差极化界面富集效应提高臭氧利用率。主要开展以下三个方面的研究：一是以纳米催化剂作为增韧剂，通过异相纳米增韧技术制备复合过渡金属氧化物纳滤膜，系统研究颗粒堆积孔和模板组装孔的匹配行为及调控方法；二是研究过渡金属氧化物复配对价态、晶相和催化活性的影响，揭示复合过渡金属氧化物的协同催化作用机制；三是考察臭氧环境下纳滤膜表面的浓差极化演变过程，基于浓差极化模型中的薄膜理论和催化反应动力学，构建膜反应动力学方程，初步建立复合过渡金属氧化物纳滤膜材料设计的理论方法。

面向高浓有机废水处理，以实现小分子有机物高效分离和分解为目标，探索了催化功能纳滤膜的制备方法。本项目执行期间提出了二维纳米增韧制备陶瓷复合纳滤膜的方法，有效解决了溶胶凝胶法制备陶瓷膜过程中膜开裂的问题。通过对催化机理的研究，发现催化材料高的电子迁移速率有助于催化效率的提升；在膜制备过程中引入高导电性的石墨烯、Mxene等材料，制备出了多种孔径小于3nm具有协同催化臭氧化功能的复合陶瓷纳滤膜，多种复合膜材料染料降解率为100%，染料截留率〉95%；开发出系列高级氧化膜反应器，实现了反应和分离过程的耦合。项目执行期间，累计发表文章20篇，其中SCI论文19篇，影响因子大于5的文章9篇，累计被引90余次。在膜领域顶级期刊J.Memebran.Sci（IF=7.01）发表论文4篇，在化工领域顶级期刊Chem. Eng. J(IF=10.04) 上发表文章2篇。申请专利6件，3件获授权。培养研究生10名，参加国内外学术会议9次。全面完成了计划任务的各项指标。