Preparation of gelatin-modified nano-iron and the effect on removing methyl orange

In this paper, the gelatin-modified nano-iron was prepared by the liquid-reduction process. Scanning electron microscopy (SEM), infrared spectrumas well as sedimentation rate were used to characterize the prepared samples. The effect of the gelatin-modified nano-iron on removing methyl orange (MO) was investigated. The results show that the dispersion and stability of the gelatin-modified nano-iron are significantly improved; the combining mechanism between the gelatin and the nano-iron is deduced to be the coordination between the iron and the amino nitrogen of the gelatin; the removal rate of MO by the gelatin-modified nano-iron is higher than that by the non-modified one; the initial concentration of MO, the initial pH value and the content of dissolved oxygen have negative effects on the removal rate, but the amount of the modified nano-iron and temperature have positive effects; NO3– and CO32– inhibit the removal of MO, and the concentration of SO42– determines its effect on the removal is positive or negative.