Oxidative degradation of clindamycin in aqueous solution using nanoscale zero-valent iron/H2O2/US

Abstract

In this study, we investigated clindamycin (CLM) removal efficiency by using nanoscale zero-valent iron (nZVI) particles in the presence of hydrogen peroxide and sonolysis process. Laboratory experiments were performed at 21 ± 2˚C. Also, the effects of initial CLM concentration (45, 80, and 100 mg/L), the molar ratio of H 2 O 2 (0.1, 0.5, and 1 mM), nZVI (0.06, 0.1, and 0.2 g/L), pH (3, 7, and 10), in the presence of ultrasonic waves (35 and 130 kHz with 500 W power) were studied. The results demonstrated that the sonolysis process combined with nZVI and H 2 O 2 in nZVI/H 2 O 2 /US system improved the degradation efficiency. Results indicate that the CLM degradation rate increased with decreasing pH and increasing contact time, temperature, nZVI concentration (0.2 g/L), H 2 O 2 concentration (to 180 mM), and ultrasound frequency (130 kHz/500 W). The optimal concentration of the H 2 O 2 , according to the extent of the Å OH scavenging reaction with these reagents, was demonstrated for CLM removal.

Degradation Reactive Black 5 dye from aqueous solutions using ozonation with pumices and pumices modified by nanoscale zero valent iron (nZVI)

“…The aqueous ozone concentration was determined by spectrophotometry using the indigo method (Clesceri et al, 1996). The COD was measured by Open reflex methods (Gholami et al, 2016).…”

“…Advanced oxidation processes (AOPs) are alternative methods for the elimination of types of refractory compounds, principally due to the formation of hydroxyl radicals (HO•). During advanced oxidation processes (AOPs), additional reactions occur in the presence of light that produce hydroxyl radicals or increase the production rate of hydroxyl radicals that are capable of rapidly oxidizing organic contaminants and converting them into harmless end-products, such as H 2 O and CO 2 , and inorganic ions from atoms, which have been successfully used for the treatment of wastewaters from petrochemical, textile, and pharmaceutical industries (Dimoglo et al, 2004;Tekin et al, 2006;Chakinala et al, 2009;Nachiappan and Muthukumar, 2010;Oller et al, 2011;Farzadkia et al, 2014;Wang et al, 2014;Gholami et al, 2016). Previous studies have documented the removal/degradation of benzotriazole with advanced techniques in recent years (e.g., ferrate (VI) oxidation, ultrasonic, adsorption,…”

A Novel Green Synthesis of Zero Valent Iron Nanoparticles (Nzvi) using Walnut Green Skin Characterization, Catalytic Degradation and Toxicity Studies

“…6. Because pH is the most effective parameter in the performance of chemical processes and it has a great effect on the reactions [38], in this study, the effect of pH changes from 3 to 11 was investigated. At pHs above 4, Fe 2 + ions are converted to Fe 3 + , which has little ability to activate PS and produce SO 4…”

“…That is why the process e ciency is high in acidic conditions. Also, in neutral pH, sulfate and hydroxyl radicals react with each other so that the reactor is free of radicals and, in turn, the process e ciency declines [39].The results of other studies also show that, in Fenton and Fenton-like processes (PS/nZVI process), the highest e ciency is reached in acidic conditions at a pH of 2 to 4 [5,38,40]. Particularly, acidic conditions are favorable for the formation and maintenance of ferrous ions (Fe 2+ ) that play an important role in producing sulfate radicals [18].…”

Degradation of 4-chlorophenol in aqueous solution by dielectric barrier discharge system: effect of fed gases

“…Although the advanced oxidation processes have been successfully used to remediate different organic pollutants or disinfection purposes, they are commonly require the addition of chemical agents [5][6][7][8][9]. and the full scale application of other methods such as adsorption processes require high contact time and limited by the slow rate of process [10][11][12]. Meanwhile, the advanced oxidation processes based on plasma discharges are novel and promising alternatives.…”