Fu Hongbo, Quan Xie
School of Environmental and Biological Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian 116023, PR China.
Chemosphere. 2006 Apr;63(3):403-10. doi: 10.1016/j.chemosphere.2005.08.054. Epub 2005 Nov 15.
The present work extended our knowledge on the binding and complexation of a fulvic acid (FA) derived from leonardite and the iron oxides (hematite, goethite and akaganeite) by Fourier transform infrared spectroscopy (FTIR). As a prerequisite, the iron oxides were firstly prepared and characterized by transmission electron micrograph (TEM). All iron phases were single and well-described crystalloid. The FTIR data obtained by two different sampling preparation methods gave the consisting evidences that under our experimental conditions the interaction mechanism was to the ligand-exchange involving carboxylic functional groups of the FA and the surfaces sites of both hematite and goethite, while no complexation can be evidenced in the case of akaganeite, only surface adsorption. In general, the binding affinities of the iron oxides with the FA was in the order of hematite>goethite>akaganeite. The present method, although associated with some uncertainties, provided an opportunity to increase the knowledge in the field of the humic chemistry.
本研究通过傅里叶变换红外光谱（FTIR）扩展了我们对源自泥煤褐铁矿的富里酸（FA）与铁氧化物（赤铁矿、针铁矿和纤铁矿）之间结合和络合的认识。作为前提条件，首先制备了铁氧化物并用透射电子显微镜（TEM）进行了表征。所有铁相均为单一且描述清晰的晶体。通过两种不同的样品制备方法获得的FTIR数据提供了一致的证据，即在我们的实验条件下，相互作用机制是涉及FA的羧基官能团与赤铁矿和针铁矿表面位点的配体交换，而在纤铁矿的情况下，没有络合现象，只有表面吸附。一般来说，铁氧化物与FA的结合亲和力顺序为赤铁矿>针铁矿>纤铁矿。本方法虽然存在一些不确定性，但为增加腐殖化学领域的知识提供了一个机会。
