Chang Ming C, Kang Hung Y
Department of Safety, Health and Environmental Engineering, Hungkuang University, Taichung County, Taiwan.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2009 May;44(6):576-82. doi: 10.1080/10934520902784609.
Laboratory experiments were conducted to assess pyrene removal from soil using synthesized nanoscale zero-valent iron (nZVI) particles. Batch experiments indicated that nZVI particles were more efficient in removing pyrene than commercially available microscale ZVI (mZVI, < 10 microm) particles. Reaction kinetics of pyrene removal were dominated by the iron dosage and approximated by a pseudo-first-order model. The reaction rate constants (k) were 0.135 +/- 0.030 and 0.103 +/- 0.023 min(-1) when 0.01 g nZVI and mZVI particles were amended to batch vessels containing one gram of pyrene-spiked soil (100 mg pyrene per kg dried soil), respectively. The pH and oxidation-reduction potential (ORP) did not change significantly in experiments with mZVI particles. In experiments with nZVI particles, however, pH slowly increased from 4.8 to 8.5 due to hydroxide production, and ORP rapidly decreased from +400 to -550 mV. ORP continued to decline to -700 mV when additional nZVI particles were added. The results from this study indicate that nZVI particle addition produced strongly reducing conditions and suggest that remediation of pyrene-contaminated soils using nZVI particles is a promising technology.
开展了实验室实验，以评估使用合成的纳米级零价铁（nZVI）颗粒从土壤中去除芘的效果。批量实验表明，nZVI颗粒比市售的微米级零价铁（mZVI，<10微米）颗粒在去除芘方面更有效。芘去除的反应动力学受铁剂量的主导，并可用准一级模型近似。当向含有一克芘污染土壤（每千克干土含100毫克芘）的批量容器中分别添加0.01克nZVI和mZVI颗粒时，反应速率常数（k）分别为0.135±0.030和0.103±0.023分钟-1。在使用mZVI颗粒的实验中，pH值和氧化还原电位（ORP）没有显著变化。然而，在使用nZVI颗粒的实验中，由于产生氢氧化物，pH值从4.8缓慢增加到8.5，ORP从+400迅速下降到-550毫伏。当添加额外的nZVI颗粒时，ORP继续下降至-700毫伏。本研究结果表明，添加nZVI颗粒会产生强还原条件，并表明使用nZVI颗粒修复芘污染土壤是一项有前景的技术。
