Insight into natural medium remediation through ecotoxicity correlation with clay catalyst selectivity in organic molecule ozonation

Abstract

The oxidative degradation of diazinon (DAZ) and diclofenac sodium (DCF) in aqueous media was comparatively investigated and correlated to the mortality of Artemia salina in the presence of clay catalysts....

Ecotoxicity of Diazinon and Atrazine Mixtures after Ozonation Catalyzed by Na+ and Fe2+ Exchanged Montmorillonites on Lemna minor

“…The latter should be strongly influenced by the unavoidable pH decrease during ozonation. Indeed, various clay–clay, pesticide–clay, pesticide–ozone, clay–ozone, and more particularly those involving silanol groups (-Si-O-H) can take place according to the pH level attained [ 16 , 47 ].…”

“…The specific feature of the exchangeable cations determines the type of clay–clay and clay–reactant interactions. Unlike in dry media, the particle size of both montmorillonites significantly varies according to charge-compensating cations and the chemical composition of the clay suspension concentration and pH [ 16 , 47 , 55 ]. These factors will govern the intensity and pathway of the pesticide degradation process, providing evidence that pesticide persistence in nature depends on the type and chemical composition of the host-medium, in agreement with the targeted objective.…”

“…Fully ion-exchanged Na + and Fe 2+ -montmorillonite-rich materials (NaMt and Fe(II)Mt, respectively) were prepared through purification of a crude bentonite supplied by Sigma-Aldrich (Burlington, MA, USA) according to a procedure described previously [ 16 ]. Preliminary characterization through X-ray diffraction (Siemens D5000, CuKα, λ = 1.54051 Å) of both montmorillonites revealed no crystallinity loss.…”

“…Clay catalysts display expandable structure without pore size limitation and coagulation-flocculation capacity that allow easy recovery after settling. Among clay catalysts, montmorillonite ion-exchanged by alkaline metal and transition metal was found to exhibit high catalytic activity in the ozonation of organic molecules [ 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ].…”

Clay-Catalyzed Ozonation of Hydrotalcite-Extracted Lactic Acid Potential Application for Preventing Milk Fermentation Inhibition

“…LA ozonation was already investigated in the absence [ 34 , 35 ] and presence of solid catalysts [ 36 , 37 , 38 , 39 , 40 , 41 , 42 ], low cost, non-toxic and widely available smectites such as bentonite and derivatives [ 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 ] but scarcely in the presence of hydrotalcite [ 34 , 35 ]. Among smectites, montmorillonite (Mt) can be used as co-catalyst to improve Ht regeneration by ozonation.…”