POPs Research Center, Department of Environmental Science and Engineering, Tsinghua University, Beijing, PR China.
Bioresour Technol. 2011 Feb;102(3):2265-71. doi: 10.1016/j.biortech.2010.10.040. Epub 2010 Oct 15.
The crosslinked chitosan beads were used as an efficient biosorbent to remove perfluorooctane sulfonate (PFOS) from aqueous solution. The chitosan biosorbent had a sorption capacity up to 5.5 mmol/g for PFOS at the equilibrium concentration of 0.33 mmol/L, much higher than some conventional adsorbents. The sorption kinetics indicated that the sorption equilibrium was reached quickly at high pH and low PFOS concentrations, and the adsorbent size also affected the sorption rate to some extent. The double-exponential model described the kinetic data well, and the sorption of PFOS on the chitosan beads was a diffusion-controlled process. Based on the sorption kinetics and adsorbent characterization, the uptake mechanisms including electrostatic and hydrophobic interactions were identified to be responsible for PFOS sorption, and the hemi-micelles and micelles may form in the porous structure due to high PFOS concentrations within the adsorbent, which had the main contribution to the high sorption capacity.
交联壳聚糖珠被用作一种高效的生物吸附剂，用于从水溶液中去除全氟辛烷磺酸 (PFOS)。在平衡浓度为 0.33 mmol/L 的条件下，壳聚糖生物吸附剂对 PFOS 的吸附容量高达 5.5 mmol/g，远高于一些传统的吸附剂。吸附动力学表明，在高 pH 值和低 PFOS 浓度下，吸附平衡很快达到，吸附剂的粒径也在一定程度上影响吸附速率。双指数模型很好地描述了动力学数据，PFOS 在壳聚糖珠上的吸附是一个扩散控制的过程。基于吸附动力学和吸附剂特性，可以确定吸附 PFOS 的机制包括静电相互作用和疏水相互作用，并且由于吸附剂内 PFOS 浓度较高，可能会在多孔结构中形成部分胶束和胶束，这是高吸附容量的主要原因。
