| 地下环境中Fe2+对硝基苯的还原衰减作用模拟研究 |
| 摘要点击 3814 全文点击 2034 投稿时间：2010-05-18 修订日期：2010-07-12 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 二价铁 硝基苯 还原衰减 还原效率 水化学组成 |
| 英文关键词 ferrous nitrobenzene(NB) reductive attenuation deoxidization efficiency hydrochemical constituents |
|
| 中文摘要 |
| 研究了地下环境中的Fe2+对硝基苯(NB)的还原衰减作用，模拟了Fe2+还原硝基苯的过程及不同硬度、 CO2-3、 SO2-4、 NO-3、 Cl-等地下水化学组成对反应的影响，目的是阐明Fe2+还原硝基苯的机制及水化学组成对反应影响的原因.结果表明，在温度为10℃、 pH为6.8的条件下，Fe2+和硝基苯浓度皆对其还原衰减有影响，当n(Fe2+)∶n(NB)为5.88∶1时硝基苯还原效率最高，48 h后其还原效率为57.63%.镁硬度、 CO2-3对Fe2+还原硝基苯有一定抑制作用，当镁硬度、 CO2-3分别达到150 mg/L和50 mg/L时，48 h后硝基苯还原效率最大为51.05%和49.96%，且随着镁硬度、 CO2-3浓度的增大抑制作用越显著，当Mg2+浓度增至800 mg/L时，48 h后还原效率仅为6.98%；SO2-4、 NO-3、 Cl-对还原反应影响较小，48 h后还原效率＜50%；HCO-3加快了还原反应的进行，8 h后硝基苯的还原效率可达60%.本研究探索了硝基苯污染场地中Fe2+对其自然衰减的贡献，为定量估算污染场地的自然衰减程度提供了一定的理论依据. |
| 英文摘要 |
| Experiments were conducted to investigate reductive attenuation of nitrobenzene (NB) by Fe2+ in subsurface environment and influences of hydrochemical constituents such as water hardness,SO2-4,NO- 3and Cl-.Experimental results indicated that concentration of Fe2+ and NB both had influences on NB reduction. The highest reducing efficiency obtained while n(Fe2+)∶n(NB) was 5.88∶1 under the condition of pH 6.8 and 10℃. The deoxidization efficiency of NB was up to 57.63% over 48 h. Mg2+ and CO2- 3could inhibit the reduction of NB,and the reduction efficiency reached 51.05% and 49.96% in 48 h while Mg2+ was 150 mg/L and CO2- 3was 50 mg/L,respectively;the inhibition was enhanced with increasing of Mg2+and CO2-3 concentration,and the deoxidization efficiency of NB was 6.98% only while Mg2+ was 800 mg/L. SO2-4,NO-3 and Cl- have small influence on NB reduction,the deoxidization efficiency was less than 50% in 48 h. HCO-3 can accelerate the reaction,and the reduction efficiency was up to 60% in 8h. These baseline relationships provide a way to quantitatively evaluate the extent of natural attenuation in contaminated site. |
