Surfactant-enhanced in-situ chemical oxidation (S-ISCO) is widely applied in soil and groundwater remediation. However, the role of surfactants in the reactive species (RSs) transformation remains inadequately explored. This work introduced nonionic surfactant Tween-80 (TW-80) into a nano zero-valent iron (nZVI) activated persulfate (PS) system.
View Article and Find Full Text PDFThe application of S(IV) for the regeneration of Fe(II) has been widely investigated. As the common S(IV) sources, sodium sulfite (NaSO) and sodium bisulfite (NaHSO) are soluble in the solution, resulting in excessive SO concentration and redundant radical scavenging problems. In this research, calcium sulfite (CaSO) was applied as the substitution for the enhancement of different oxidant/Fe(II) systems.
View Article and Find Full Text PDFS(IV)-based advanced oxidation process has been applied for contaminants remediation. However, as a traditional source of sulfite (SO), NaSO is extremely soluble in water, resulting in a high concentration of SO to quench the generated reactive oxygen species (ROS). In this work, CaSO was introduced instead of NaSO for its slow-released SO ability and Fe(III)/CaSO system was established for the removal of trichloroethylene (TCE) and other organic contaminants.
View Article and Find Full Text PDFIn this work, the effect of different desorbents (low molecular weight organic acids (LMWOAs), surfactants, and inorganic salts) on naphthalene (NAP) desorption in soil was investigated, and the results showed that NAP desorption pattern fitted the pseudo-second-order kinetics. The addition of LMWOAs, especially citric acid (CA), could stimulate the reactive oxygen species (ROS) generation and NAP degradation in Fe(II) activated persulfate (PS) system, while the presence of surfactants and CaCl could inhibit the NAP removal due to the competitive consumption of ROS. The maximum removal of NAP was 97.
View Article and Find Full Text PDFFew researches have focused on the role of nanoscale zero-valent iron (nZVI) in Fenton-like process for polycyclic aromatic hydrocarbons (PAHs) removal. In this study, the naphthalene (NAP) degradation tests in ultrapure water showed that nZVI addition could enhance NAP degradation from 79.7% to 99.
View Article and Find Full Text PDFThe performance of naphthalene (NAP) degradation in peroxodisulfate (PDS) and peroxymonosulfate (PMS) oxidation systems by nano zero valent iron (nZVI) combined with citric acid (CA) activation was reported in aqueous solution and soil slurry medium. The results in aqueous solution tests indicated that 98.1% and 98.
View Article and Find Full Text PDFIn this study, amorphous boron was employed as a reductant in traditional Fenton system for the first time to accelerate the regeneration of Fe(II). The degradation of 1,2-dichloroethane (DCA) was only 40.0% in Fenton system, while in the presence of amorphous boron, it could reach to 93.
View Article and Find Full Text PDFA novel catalyst of sulfidated iron-nickel supported on biochar (S-FeNi@BC) was synthesized to activate persulfate (PS) for the removal of trichloroethylene (TCE). A number of techniques including XRD, SEM, TEM, FTIR, BET and EDS were employed to characterize S-FeNi@BC. The influence of sulfur to iron ratio (S/F) on TCE removal was investigated by batch experiments and a higher TCE removal (98.
View Article and Find Full Text PDFThe presence of polycyclic aromatic hydrocarbons (PAHs) in groundwater is making a great threat to human health in the world which has received an increasing environmental concern. Among various Fenton oxidation processes, 97.6%, 92.
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