Université européenne de Bretagne, Université de Bretagne Occidentale, UMR CNRS 6521, Département de Chimie, 6 Av. Le Gorgeu, C.S. 93837, 29238 Brest Cedex 3, France.
J Colloid Interface Sci. 2010 May 15;345(2):496-504. doi: 10.1016/j.jcis.2010.01.090. Epub 2010 Feb 6.
This laboratory study mimicked the pollution of a suspension of silica beads, used as a crude model of sand, by naphthalene in mixture with carbofuran at first, and then by this mixture in association with a metal salt, Pb(NO(3))(2). The silica properties and the working conditions were such that they allowed us to only observe physisorption, which is the first and essential step of any adsorption mechanism. Naphthalene and carbofuran were, respectively, chosen as hydrocarbon and pesticide. Naphthalene adsorption from simple solutions is rather large compared to other organic adsorptions, and carbofuran seems to adsorb on a layer of naphthalene when the latter is mixed in solution with carbofuran. Like other organics, naphthalene favours the adsorption of lead ions, but ionic adsorption is considerably increased by the combination of naphthalene and carbofuran. The Wagner-Onsager-Samaras theory shows that the result implies a special organization of organic molecules at the interface. Conclusions about some environmental mechanisms of fixation, or release, of ions on sands in the case of simple physisorption are drawn from the study.
本实验室研究模拟了沙粒的悬浮液被萘和克百威污染的情况，首先是这两种物质的混合物，然后是这种混合物与金属盐 Pb(NO3)2 的混合物。二氧化硅的性质和工作条件使得我们只能观察到物理吸附，这是任何吸附机制的第一步和关键步骤。萘和克百威分别被选为碳氢化合物和农药。与其他有机物相比，萘从简单溶液中的吸附量相当大，而当萘与克百威混合在溶液中时，克百威似乎会吸附在萘层上。与其他有机物一样，萘有利于铅离子的吸附，但萘和克百威的结合大大增加了离子的吸附。Wagner-Onsager-Samaras 理论表明，这一结果意味着在界面处有机分子的特殊组织。从这项研究中得出了关于在简单物理吸附的情况下，沙粒上离子固定或释放的一些环境机制的结论。
