Ultrasonic power improvement of flumequine degradation effectiveness in aqueous solution via direct and indirect action of mechanical acoustic wave

The current research work aimed to describe the roles of ultrasonic power under sono-Fenton process in the degradation of flumequine (FLU) in water. For this purpose, the effects of some parameters including temperature, ferrous ion concentration, chemical oxidant concentration (S₂O₈^2- and Cl^-) and the initial pH value of the reaction kinetics were investigated. Results showed that the degradation of FLU antibiotic was accelerated by ultrasonic irradiation and the presence of an inorganic oxidant. The sono-generation of active species such as hydroxyl radicals (HO and HOO) and sulfate radicals (SO₄^-) as strong oxidizing agents improved the FLU degradation. In fact, the peroxydisulfate anion (S₂O₈^2-) has been identified as among parameters that enhanced the degradation process. Under optimal conditions, 98% of the flumequine removal was carried out within 80 min at 60 °C.

Spatial distribution and contamination assessment of heavy metals in marine sediments of the southern coast of Sfax, Gabes Gulf, Tunisia

In order to investigate the current distribution of metal concentrations in surface marine sediments of the southern coast of Sfax (Tunisia), thirty-nine samples were collected in the vicinity of a mixed industrial and domestic wastewater effluent discharge. In comparison with the threshold effect level and probable effect level, the majority of metals had high ecological and biological risks. Enrichment factor and geoaccumulation Index showed that the majority of sediments are unpolluted by As, Ni and Pb, moderately polluted by Cr and Cu and moderately to strongly polluted by P, Y, Zn. Besides, all sites are extremely polluted by Cd. Principal component analysis indicates that As, Cu and Ni were mainly from lithogenic sources, whereas Cd, Cr, F, P, Pb, Y and Zn were mainly derived from anthropogenic source. Findings of this research can be used as suitable reference for future studies and environmental management plans in the region.