by MIAO YU, M.S. Washington State University August 2010 Chair: Richard J. Watts In situ chemical oxidation (ISCO) using persulfate is a promising technique for the remediation of soil and groundwater contaminants. Persulfate activated by iron (III)-EDTA or sodium hydroxide can accelerate the degradation of contaminants. However, in previous studies of ISCO remediation processes, the applicatio...

The feasibility of total petroleum hydrocarbon-contaminated (TPH) soil remediation was studied using persulfate oxidation. Factors tested included type of activator, persulfate concentration, number of persulfate applications, and reaction time. Probe chemicals were used to study effi ciency of the persulfate oxidation mechanism. The best activation method used Fe2+, which achieved 40.8% TPH de...

The degradation of 2-chlorophenol (2-CP) by persulfate was investigated. The kinetics of persulfate oxidation of 2-chlorophenol in aqueous solutions at various pH, oxidant concentration, temperature, Fe2+ and Cu2+ ions content was studied. Maximum of 2-CP degradation occurred at pH 8. The oxidation rate of 2-CP increased with increasing the persulfate molar excess. The degradation process was s...

Occupational allergic contact eczema and asthma caused by bleaching agents is seen in hairdressers. Bleaching agents contain persulfate salts, which are known to induce immediate reactions such as rhinitis, asthma, contact urticaria, and anaphylaxis. The immunologic mechanism is not, however, fully understood. The specific inhalation challenge test is considered to be the gold standard for diag...

Persulfate (S2O8(2-)) is being used increasingly for in situ chemical oxidation (ISCO) of organic contaminants in groundwater, despite an incomplete understanding of the mechanism through which it is converted into reactive species. In particular, the decomposition of persulfate by naturally occurring mineral surfaces has not been studied in detail. To gain insight into the reaction rates and m...

by MARISSA C. MERKER, M.S.C.E. Washington State University August 2010 Chair: Richard J. Watts Persulfate is a promising in situ chemical oxidation treatment (ISCO) for the remediation of low-permeability strata because it is more stable in the subsurface and can rapidly degrade recalcitrant contaminants compared to other technologies. ISCO technologies include catalyzed hydrogen peroxide propa...

In situ chemical oxidation (ISCO) has been widely used in recent years for the remediation of VOC contaminated soil and groundwater. Among several chemical oxidizing agents injected into the subsurface for ISCO, persulfate has often been selected due to the advantage of being less reactive and longer-lived in the subsurface environment. Through this research, the effect of side reactions occurr...

Biochar (BC) supported nanoscale zerovalent iron (nZVI) composite was synthesized and used as an activator for persulfate to enhance the trichloroethylene (TCE) removal in aqueous solutions. The degradation efficiency of TCE (0.15mmolL(-1)) was 99.4% in the presence of nZVI/BC (4.5mmolL(-1), nZVI to BC mass ratio was 1:5) and persulfate (4.5mmolL(-1)) within 5min, which was significantly higher...

Perfluorooctanoic acid (PFOA) is an emerging contaminant of concern due to its toxicity for human health and ecosystems. However, successful degradation of PFOA in aqueous solutions with a cost-effective method remains a challenge, especially for groundwater. In this study, the degradation of PFOA using activated persulfate under mild conditions was investigated. The impact of different factors...

Photocatalytic water oxidation by persulfate (Na2 S2 O8 ) with [Ru(bpy)3 ](2+) (bpy=2,2'-bipyridine) as a photocatalyst provides a standard protocol to study the catalytic reactivity of water oxidation catalysts. The yield of evolved oxygen per persulfate is regarded as a good index for the catalytic reactivity because the oxidation of bpy of [Ru(bpy)3 ](2+) and organic ligands of catalysts com...