Abstract

The conditions of chemical modification of the surface of synthetic magnetic iron oxides (magnetite Fe₃O₄, maghemite γ-Fe₂O₃) by phosphonic complexones (PBTC, HEDP, HEIDPH, NTMP, EDTMP) are studied. It is shown that the maximum concentration of grafted groups is observed upon treating iron oxides with aqueous solutions of complexones containing two or three phosphonic groups at pH 2–3 and temperature of 50–60°C for 2–6 h. To characterize the grafted layer, various physicochemical research methods (XRD, FTIR spectroscopy, the BET method, thermal analysis, acid–base titration, sorption from solutions) were used. It is found that the modifying coating significantly increases the sorption ability of magnetic iron oxides towards metal cations (Cu(II), Cd(II)). A mechanism for binding of metal ions by modified sorbents is proposed.

中文翻译：

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膦酸配合物对磁性氧化铁表面的改性

摘要

合成的磁性氧化铁的表面的化学改性的条件（磁铁矿的Fe ₃ ö ₄，磁赤铁矿γ-的Fe ₂ ö ₃）通过膦酸络合物（PBTC，HEDP，HEIDPH，NTMP，EDTMP）进行了研究。结果表明，在pH 2-3的温度和50-60°C的温度下，用含有两个或三个膦酸基的络合物的水溶液处理氧化铁，可以观察到最大的接枝基团浓度。为了表征接枝层，使用了各种物理化学研究方法（XRD，FTIR光谱，BET法，热分析，酸碱滴定，溶液吸附）。发现改性涂层显着增加了磁性氧化铁对金属阳离子（Cu（II），Cd（II））的吸附能力。提出了通过改性吸附剂与金属离子结合的机理。