Tong Le, Liu Weiting, Lin Weijia, Guo Chuling, Yang Jing, Wei Yanfu, Xie Yingying, Liu Shasha, Dang Zhi
School of Environment and Energy, South China University of Technology, Guangzhou 510006, China E-mail:
Water Sci Technol. 2017 Sep;76(5-6):1167-1176. doi: 10.2166/wst.2017.281.
The application of modified agricultural wastes for removing polycyclic aromatic hydrocarbons (PAHs) from water is gaining a growing interest. However, most modified methods using synthetic chemicals may cause secondary pollution. To overcome this limitation, in this study, a rhamnolipid modified corn stalk (RL-CS) for the removal of phenanthrene (PHE) from aqueous solution was prepared using a rhamnolipid-enhanced acid modification method. RL-CS with higher surface area and lower polarity exhibited higher PHE removal efficiency than that of raw corn stalk (RCS). The adsorption kinetics of RL-CS fitted well with pseudo-second-order kinetics (R > 0.999). Sorption coefficients and carbon-normalized sorption coefficient of RL-CS were 4.68 and 2.86 times higher than that of RCS. Sorption process of RL-CS was nonlinear. Meanwhile, the sorption was an exothermic process and could occur spontaneously. The present study demonstrated that biosurfactant-modified biosorbent RL-CS may be of great potential for the removal of low concentrations of PAHs from the contaminated waters.
利用改性农业废弃物去除水中多环芳烃（PAHs）的研究正日益受到关注。然而，大多数使用合成化学品的改性方法可能会造成二次污染。为克服这一局限性，本研究采用鼠李糖脂强化酸改性法制备了用于从水溶液中去除菲（PHE）的鼠李糖脂改性玉米秸秆（RL-CS）。具有较高比表面积和较低极性的RL-CS对PHE的去除效率高于原始玉米秸秆（RCS）。RL-CS的吸附动力学与伪二级动力学拟合良好（R>0.999）。RL-CS的吸附系数和碳归一化吸附系数分别比RCS高4.68倍和2.86倍。RL-CS的吸附过程是非线性的。同时，吸附是一个放热过程，且能自发进行。本研究表明，生物表面活性剂改性的生物吸附剂RL-CS在去除受污染水体中低浓度PAHs方面具有巨大潜力。
