Remediation of PAH-Contaminated Soil by Combining Surfactant Enhanced Soil Washing and Iron-Activated Persulfate Oxidation Process

• Published in: International journal of environmental research and public health Vol. 16; no. 3; p. 441
• Main Authors: Qiu, Yanhua, Xu, Meilan, Sun, Zongquan, Li, Helian
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 02.02.2019; MDPI
• Subjects: Alginic acid; Biodegradability; Biodegradation; Cellulose; Efficiency; Effluent treatment; Effluents; Environmental degradation; Environmental Restoration and Remediation - methods; Ethanol; Flasks; Fluoranthene; Guar gum; Hydrophobicity; Industrial pollution; Iron - chemistry; Iron sulfates; Methods; Organic matter; Oxidation; Oxidation process; Oxidation-Reduction; Phenanthrene; Pollutants; Polyacrylic acid; Polycyclic aromatic hydrocarbons; Polycyclic Aromatic Hydrocarbons - chemistry; Polycyclic Aromatic Hydrocarbons - isolation & purification; Polyethylene glycol; Polymers; Potatoes; Pyrene; Sediment pollution; Silica; Silicon dioxide; Silicon Dioxide - chemistry; Sodium; Sodium Dodecyl Sulfate - chemistry; Soil - chemistry; Soil contamination; Soil degradation; Soil Pollutants - chemistry; Soil Pollutants - isolation & purification; Soil pollution; Soil remediation; Soil treatment; Starch; Sulfur Oxides - chemistry; Surface-Active Agents - chemistry; Surfactants; Washing; Wastewater treatment; United States > US; China; Japan; PAHs; SDS; activated persulfate; soil remediation; SiO2/nZVI
• ISSN: 1660-4601; 1661-7827; 1660-4601
• DOI: 10.3390/ijerph16030441

There is increasing concern regarding soils contaminated with polycyclic aromatic hydrocarbons (PAHs) In the present study, the remediation of soil spiked with PAHs was explored by the combination of soil washing with sodium dodecyl sulfate (SDS) and subsequent oxidation through persulfate (PS) activated by Fe , nanoscale zero-valent iron (nZVI), and SiO₂-coated nZVI (SiO₂/nZVI). Results demonstrated that the removal of phenanthrene (PHE), fluoranthene (FLU), and pyrene (PYR) by SDS is an efficient means for soil decontamination. At SDS concentration of 20 g/L, the removal efficiencies of PHE, PYR, and FLU were 37%, 40%, and 44%, respectively. For the degradation of PAHs and SDS in the soil washing effluents, the efficiencies of PS activated with SiO₂/nZVI were not significantly different from those of PS activated with nZVI and Fe ( > 0.05). In practice, SiO₂/nZVI is more preferable due to the improved antioxidation and dispersibility. At the dosage of 2 g/L (in the amount of iron) of SiO₂/nZVI, the removal efficiencies of PHE, FLU, PYR, and SDS within 30 min of treatment were 75%, 85%, 87%, and 34%, respectively. The degradation of SDS was much lower than those of PAHs, which facilitated the recycle of SDS. Our findings suggest that PS activated with SiO₂/nZVI is a promising method for the treatment of soil washing effluents containing SDS and PAHs.