Chen Chih-Feng, Binh Nguyen Thanh, Chen Chiu-Wen, Dong Cheng-Di
a Department of Marine Environmental Engineering , National Kaohsiung Marine University , Kaohsiung , Taiwan , Republic of China.
J Air Waste Manag Assoc. 2015 Apr;65(4):375-83. doi: 10.1080/10962247.2014.996266.
The oxidation of 16 polycyclic aromatic hydrocarbons (PAHs) compounds in sediments by sodium persulfate (Na2S2O8) simultaneously activated by temperature and nano zero-valent iron (nZVI) as the source of catalytic ferrous iron was investigated. The effect of various controlling factors, including S2O8(2-) (0.017-170 g/L), nZVI (0.01-1 g/L), and temperature (50-70 °C) were performed. The efficiency to remove PAHs was 10.7-39.1% for unactivated persulfate. The treated sample had over 50% of the persulfate still remaining from an initial persulfate dose of 170 g/L, whereas less than 1% of the persulfate remained from an initial persulfate dose of 0.017, 0.17, and 1.7 g/L. Adequate persulfate (170 g/L) must be present because it is the source of the sulfate radicals responsible for the degradation of PAHs. Results indicated that increasing temperature and the addition of nZVI into a persulfate-slurry system could enhance the persulfate oxidation process. The best removal efficiency (90%) was achieved after 24 hr while adding nZVI (0.01 g/L) to persulfate (170 g/L) at temperature of 70 °C. The results suggested that nZVI assisted persulfate oxidation without elevating temperature may be a suitable and economic alternative for the ex situ treatment of PAH-contaminated sediments.
Nano zero-valent iron (nZVI) has been successfully applied to transform/degrade contaminants in soils and water. Additionally, nZVI has been used as a catalyst to activate persulfate for the treatment of various contaminants. In this study, with the support of temperature, nZVI-persulfate oxidation system for treatment of PAH-contaminated sediments was improved significantly and the treated sediment could meet remediation goals.
研究了以温度和纳米零价铁（nZVI）作为催化亚铁源同时活化过硫酸钠（Na₂S₂O₈）对沉积物中16种多环芳烃（PAHs）化合物的氧化作用。考察了各种控制因素的影响，包括S₂O₈²⁻（0.017 - 170 g/L）、nZVI（0.01 - 1 g/L）和温度（50 - 70℃）。未活化过硫酸盐去除PAHs的效率为10.7 - 39.1%。对于初始过硫酸盐剂量为170 g/L的处理样品，仍有超过50%的过硫酸盐残留，而对于初始过硫酸盐剂量为0.017、0.17和1.7 g/L的样品，过硫酸盐残留量不到1%。必须存在足够的过硫酸盐（170 g/L），因为它是负责PAHs降解的硫酸根自由基的来源。结果表明，提高温度以及向过硫酸盐浆液体系中添加nZVI可以增强过硫酸盐氧化过程。在70℃下向过硫酸盐（170 g/L）中添加nZVI（0.01 g/L）24小时后，实现了最佳去除效率（90%）。结果表明，nZVI辅助过硫酸盐氧化且不升高温度可能是原位处理PAH污染沉积物的一种合适且经济的替代方法。
纳米零价铁（nZVI）已成功应用于转化/降解土壤和水中的污染物。此外，nZVI已被用作催化剂来活化过硫酸盐以处理各种污染物。在本研究中，在温度的支持下，用于处理PAH污染沉积物的nZVI - 过硫酸盐氧化系统得到了显著改进，处理后的沉积物能够达到修复目标。
