纳米ZrO2-SRB颗粒对酸性铬和氟污染地下水的修复

Repair of chromium and fluorine contaminated groundwater by nanoparticles ZrO2-SRB

为使北京某地区地下水中超标污染物F-、Cr(Ⅵ)、Cr(Ⅲ)、SO42-等离子得到有效处理,基于微生物固定化技术,将所合成的纳米ZrO2-聚丙烯酰胺杂化材料作为包埋剂,对硫酸盐还原菌(SRB)进行固定化处理形成纳米ZrO2-SRB颗粒,通过单因素实验优化了纳米ZrO2-SRB颗粒对污染地下水的最佳反应条件。结果表明:当SRB投加量为35%、杂化材料投加量为300 mL、温度为35℃时,对地下水中F-、Cr(Ⅵ)、Cr(Ⅲ)、SO42-的去除率分别为92.4%、99.8%、99.7%、70.4%。还原和吸附动力学拟合结果表明:SRB对Cr(Ⅵ)、SO42-的还原过程符合一级还原动力学;杂化材料对F-、Cr(Ⅵ)、Cr(Ⅲ)、SO42-的吸附过程符合二级吸附动力学。以上结果为处理铬和氟污染地下水提供重要的参考依据。

In order to effectively treat the excessive pollutants in groundwater,such as F-,Cr(Ⅵ),Cr(Ⅲ),SO42- in a certain area of Beijing,based on microbial immobilization technology,the nano-ZrO2-SRB particles were prepared through immobilization of sulfate reducing bacteria(SRB) with the embedding agent of a type of nano ZrO2-polyacrylamide hybrid material made in laboratory.The optimum reaction conditions of nano-ZrO2-SRB particles reparing polluted groundwater were determined through single factor test.The experimental results showed that at SRB dosage of 35%,the hybrid material dosage of 300 m L,and the reaction temperature of 35 ℃,the removal rate of F-,Cr(Ⅵ),Cr(Ⅲ),SO42- in groundwater reached 92.4%,99.8%,99.7% and 70.4%,respectively.The fitting results of reduction and adsorption kinetics showed that the reduction process of Cr(Ⅵ),SO42- by SRB was in accordance with the first-order reduction kinetics,and the adsorption process of F-,Cr(Ⅵ),Cr(Ⅲ),SO42- by hybrid materials was in accordance with the second-order adsorption kinetics.It provides an important reference for the treatment of groundwater polluted by chromium and fluorine.