School of Civil and Environmental Engineering, Georgia Institute of Technology, 311 Ferst Drive NW, Atlanta, Georgia 30332-0512, United States.
Environ Sci Technol. 2010 Dec 15;44(24):9445-50. doi: 10.1021/es100997a. Epub 2010 Nov 11.
Batch reactor experiments were performed to determine the effects of solids on the oxidation of tetracholoroethylene (PCE) by sodium persulfate in aqueous solution. Based on the rates of PCE degradation and chloride formation, PCE oxidation by heat-activated sodium persulfate at 50 °C in the presence of solids ranged from no detectable oxidation of PCE to the levels observed in water-only reactors. Repeated doses of sodium persulfate, undertaken to overcome the inherent solids oxidant demand, improved the rate and extent of PCE oxidation in reactors containing reference solids; however, no improvement was observed in reactors containing field soils. Additionally, no improvements in PCE oxidation were observed after pretreating Great Lakes and Appling soils with ca. 15 g/kg of sodium persulfate or 30% hydrogen peroxide to remove oxidizable fractions, or acetic acid to remove the carbonate fraction. Based on these results, in situ treatment of Great Lakes and Appling soils with heat-activated sodium persulfate is not anticipated to result in substantial PCE oxidation, while in situ treatment of Fort Lewis soils is anticipated to result in PCE oxidation. This work demonstrates the need to perform soil-specific contaminant treatability tests rather than soil oxidant demand tests when determining oxidant dosage requirements.
进行了批式反应器实验，以确定固体对四氯乙烯（PCE）在水溶液中被过硫酸钠氧化的影响。基于 PCE 降解和氯离子形成的速率，在 50°C 下热激活过硫酸钠存在固体时的 PCE 氧化范围从无法检测到 PCE 的氧化到仅在水中反应器中观察到的水平。为了克服固体内在的氧化剂需求，重复投加过硫酸钠，提高了含有参考固体的反应器中 PCE 氧化的速率和程度；然而，在含有田间土壤的反应器中没有观察到任何改进。此外，在用约 15 g/kg 的过硫酸钠或 30%的过氧化氢预处理大湖和阿普林土壤以去除可氧化部分，或用乙酸去除碳酸盐部分后，PCE 氧化没有观察到任何改善。基于这些结果，预计在原位处理大湖和阿普林土壤时，热激活过硫酸钠不会导致大量的 PCE 氧化，而预计在原位处理路易斯堡土壤时会导致 PCE 氧化。这项工作表明，在确定氧化剂剂量要求时，需要进行特定土壤污染物可处理性测试，而不是土壤氧化剂需求测试。
