Comparison between UVA- and zero-valent iron-activated persulfate processes for degrading propylparaben

Conventional wastewater treatments are not efficient in removing parabens, which may thus end up in surface waters, posing a threat to aquatic biota and hu     

Phenol degradation using combined effects of hydrodynamic cavitation and oxidant: Doehlert matrix

Hydrodynamic cavitation (HC)-based treatments have been proposed for the degradation of phenol as a toxic pollutant. The present work aimed to optimize the degradation of phenol using HC by means of Doehlert experimental design, which has not been previously addressed. Initially, operational parameters of hydraulic characteristics of the pump, inlet pressure, solution pH, and initial concentration were optimized; later, the effects of pH solution and H₂O₂ loading or initial pollutant concentration on phenol degradation were explored using the Doehlert experimental design. It was observed that phenol degradation is strongly dependent on the pH of the solution. Also, the acidic condition favors the formation of hydroxyl radicals and thus, the degradation of phenol. Based on the Doehlert matrix, the 94.1% phenol degradation and 68.60% total organic carbon (TOC) were obtained in 180 min at 304.5 mg/L of hydrogen peroxide at an initial concentration of 20 mg/L, 2.0 pH, and 90 psi inlet pressure, providing a cavitational yield of 6.33 × 10⁻⁶ mg/J and minimum treatment cost of US$/L 0.13. Overall, it has been observed that HC can be a promising route for the removal of pollutants (phenol) effectively using hydrogen peroxide as an additive.     

Enhancing the visible-light photoactivity of silica-supported TiO2 for the photocatalytic treatment of pharmaceuticals in water

Environmental Science and Pollution Research - Catalyst samples based on SiO2-supported TiO2 were prepared with the incorporation of Ag (metal), S (nonmetal), and ZnO@S (semiconductor and...