Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266100, China; College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China.
College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China.
Ecotoxicol Environ Saf. 2019 Mar;169:144-149. doi: 10.1016/j.ecoenv.2018.11.007. Epub 2018 Nov 13.
The surficial sediment samples collected from the Sanggou Bay in China were treated by a sequential extraction procedure. After removal of calcite, organic matter and Fe/Mn oxides, P adsorption onto the sediment residues was then evaluated through kinetic and thermodynamic characteristics. The sorption kinetic curves could be described by a two-compartment first order equation. The sorption isotherms fit well with the Langmuir and Freundlich equations. The HCl-treated sediments with calcite removed showed a rising fraction of the rapid step and a higher P adsorption potential compared with the un-extracted samples. For the clay minerals and silicate residue after NHOH·HCl treatment, the rapid step fraction was dominant, the sorption capability was prohibited, and the process was much more reversible than the original and previously-generated samples. An increase of temperature was favorable for the sorption. Estimation of thermodynamic parameters showed that the process was spontaneous and endothermic, with an increased randomness at the solid-liquid interface. Compared with the un-extracted sediment, the thermodynamic parameters in our case changed slightly after HCl treatment and NHOH·HCl treatment.
从中国桑沟湾采集的表层沉积物样品采用连续提取程序进行处理。在去除方解石、有机质和铁/锰氧化物后，通过动力学和热力学特性评估了磷在沉积物残渣上的吸附。吸附动力学曲线可以用双室一级方程来描述。吸附等温线很好地符合朗缪尔和弗雷德里希方程。与未提取的样品相比，经盐酸处理去除方解石的沉积物显示出快速步骤的上升部分和更高的磷吸附潜力。对于经 NHOH·HCl 处理后的粘土矿物和硅酸盐残渣，快速步骤部分占主导地位，吸附能力受到抑制，且该过程比原始样品和之前生成的样品更具可逆性。升高温度有利于吸附。热力学参数的估算表明，该过程是自发的和吸热的，固-液界面的随机性增加。与未提取的沉积物相比，在盐酸处理和 NHOH·HCl 处理后，我们案例中的热力学参数变化不大。
