Nanoqam, Department of Chemistry, University of Quebec at Montreal, QC H3C 3P8, Canada.
Dalton Trans. 2020 Dec 8;49(46):16693-16706. doi: 10.1039/d0dt02776f.
An original approach never tackled so far allowed correlating the basicity and hydrophilic character of clay catalysts to surface interaction with 17α-Ethinylestradiol (EE2) during ozonation in water. The clay catalysts were found to behave specifically according to their silica/alumina ratio like soils in natural oxidative processes. Acid-activated bentonites (HMt) and ion-exchanged montmorillonite (NaMt and Fe(ii)Mt) showed catalytic activity in the ozonation of 17α-ethinylestradiol (EE2) in aqueous media. In the absence of catalysts, the degradation of (EE2) reached 72% after one minute of ozonation and 99.5% after 60 minutes. In the presence of Fe(ii)Mt, EE2 degradation (96%) was achieved after only one minute of ozonation. Under similar conditions, almost total degradation to 99.99% was registered in 15 minutes of ozonation but without total mineralization of the intermediates. Moderately acid-activated bentonites exhibited higher activity affording total mineralization within a short period of ozonation. The catalytic activity of clay catalysts was found to correlate with their surface basicity and hydrophilic character. The results obtained herein allow understanding soil behavior in natural oxidative degradation of organic molecules and envisaging effective soil-based catalysts with surface properties judiciously tailored according to the nature of organic pollutants in solvent free media.
一种迄今为止从未被采用过的创新方法使得可以将粘土催化剂的碱性和亲水性与臭氧氧化过程中与 17α-乙炔基雌二醇（EE2）的表面相互作用相关联。研究发现，粘土催化剂的行为与天然氧化过程中的土壤相似，具体取决于其二氧化硅/氧化铝的比例。酸活化膨润土（HMt）和离子交换蒙脱石（NaMt 和 Fe(ii)Mt）在水介质中对 17α-乙炔基雌二醇（EE2）的臭氧氧化表现出催化活性。在没有催化剂的情况下，EE2 在臭氧氧化一分钟后降解了 72%，六十分钟后降解了 99.5%。在 Fe(ii)Mt 的存在下，仅在臭氧氧化一分钟后，EE2 的降解率达到 96%。在相似的条件下，在 15 分钟的臭氧氧化过程中登记到几乎完全降解至 99.99%，但中间体没有完全矿化。适度酸活化的膨润土表现出更高的活性，在短时间内提供完全矿化。粘土催化剂的催化活性与它们的表面碱性和亲水性有关。本文的结果使得可以理解土壤在有机分子的天然氧化降解中的行为，并可以设想在无溶剂介质中根据有机污染物的性质合理调整表面特性的有效基于土壤的催化剂。
