Amidotrizoic Acid

Iodinated contrast medias (ICMs) can act as an iodine source to react with dissolved organic matter (DOM) in the chlorination process to form toxic iodinated disinfection byproducts (I-DBPs). In this study, a coupled process of electrically activated PMS and electrocoagulation (EO-PMS/EC) was constructed to simultaneously remove iopamidol (IPM) and DOM, which has a dual control effect on the formation of I-DBPs. This system achieved a 90.1 % degradation rate of IPM, as well as remarkable removal of DOM. Firstly, the effects of experimental conditions and water matrix on IPM degradation were investigated; ¹O₂, HO^·, SO₄^·-, O₂^·- and Fe (IV) are the main contributors to IPM degradation. Moreover, the transformation pathways of IPM were inferred and most of the intermediates were less toxic compared to I-DBPs. The formation of I-DBPs was reduced by 82.7 % and was effectively inhibited in all three real water samples. Furthermore, the developed QSAR model illustrate that the degradation rate constants of ICMs are positively correlated with the values of their highest occupied molecular orbital energies and dipole moments. This study provided a more effective I-DBPs reduction strategy which reduced the environmental risk of I-DBPs to a certain extent.

Two-dimensional cage-in-cage carbon-coated FeSeS superlattices with varying degrees of sulfidation (FeSeS@C) are developed for activating peroxymonosulfate (PMS) to effectively degrade diatrizoic acid (DTZ), and the intrinsic origin that govern the activity of FeSeS@C are deeply elucidated.Exptl. and theor. analyses manifested that proper sulfidation led to increased surface acidity of FeSeS@C.The high surface acidity can optimize the exposure and spin state of Fe sites for FeSeS@C-4, a high spin state of Fe (6.27μB) not only regulating PMS adsorption for enhancing the charge d., but also expediting interfacial charge deliver to trigger the efficient PMS activation.Therefore, among FeSeS@C, FeSeS@C-4 exhibited the best degradation performance for DTZ, with first-order kinetic rate constants (kobs) of 0.232 min^-1 and degradation rate of 100%.This study demonstrates a novel application of cage-in-cage superlattices in environmental remediation and offers new insights into the mechanism of PMS activation by sulfur modification Fe-based catalysts.