尖晶石铁氧体催化过硫酸盐分解水中有机物效能与机理

The cost of persulfate was low and it produced S04-o with strong oxidation ability after being catalyzed. The advanced oxidation technology of catalyzed persulfate would have better practical application than that of ozonation oxidation with high cost in drinking water treatment.The reaction of present persulfat catalyzed mode was very low. How to activate peroxydisulfate to produce S04-o effectively,rapidly and with low energy was the key to decide if this technology could be widely used in drinking water treatment. Our recent studies showed that magnetic ferrospinel with versatility catalyst structure could induce peroxydisulfate degradation rapidly in water.The high-performance heterogeneous oxidation system of ferrospinel/peroxydisulfate were set up to decompose organic pollutants in the water. Series of magnetic ferrospinel catalysts were prepared, the rules between different water conditions,micro structure of the catalysts and the activation of peroxydisulfate to produce S04-o were studied deeply. The induced mechanism of S04-o by the catalysts were investigated combining the rules of peroxydisulfate change and the production of S04-o. And this provided the theory support for practical application of peroxydisulfate catalyzed using ferrospinel in drinking water treatment.

过硫酸盐成本低、无需现场制备、经催化后能够产生强氧化性硫酸自由基（S04-o），催化过硫酸盐高级氧化技术在饮用水有机污染物去除方面将会比成本较高的臭氧氧化技术更具备应用前景。但现有的过硫酸盐催化方式反应慢，如何高效、快速、无能耗地催化过硫酸盐产生S04-o是决定其是否能在饮用水处理中大规模应用的技术难点。申请者前期研究发现具有磁性和多变微观界面特性的尖晶石铁氧体能快速催化水中过硫酸盐分解，由此构建高效、无能耗的尖晶石铁氧体/过硫酸盐非均相催化氧化体系分解水中有机物。制备物相及元素组成可控的磁性尖晶石系列催化剂，深入研究其微观结构、不同水质条件与催化过硫酸盐产生S04-o活性间的规律，探讨提高过硫酸盐分解率和S04-o利用率的方法，结合水中硫酸盐变化及S04-o生成规律，揭示催化剂催化过硫酸盐机制。为尖晶石铁氧体催化过硫酸盐在饮用水深度处理的实际应用提供理论支持。

过硫酸盐具有方便保存、成本低、反应不受pH影响等特点，活化后能产生氧化性强、寿命比•OH更长的SO4-•。本研究构建高效、磁性尖晶石铁氧体/过硫酸盐非均相催化氧化体系去除水中有机物。首先，采用溶胶-凝胶法制备不同A位的尖晶石铁氧体系列催化剂(MFe2O4)、不同元素掺杂尖晶石铁氧体催化剂(NxN1-xFe2O4)及共沉淀法制备石墨烯负载尖晶石铁氧体催化剂，水热法制备铜铁矿型CuFeO2催化剂，催化过硫酸盐降解水中有机物，并利用现代分析测试技术对催化剂进行表征。然后，研究不同催化体系中催化剂与有机物分解性能关系，筛选效率最高的催化剂；考察不同实验因素对过硫酸盐分解反应影响；测定不同催化过硫酸盐体系中自由基种类，研究自由基产生的过程；通过探究尖晶石铁氧体催化前后体系中催化剂表面官能团、氧化还原电位、元素化合价态变化等，研究催化剂微观结构、催化过硫酸盐分解产生SO4-•机理；所有催化体系中金属离子溶出量均低于国家规定标准，且循环使用5次以上仍能保持较好的催化性能。