草鱼鱼鳞对刚果红的吸附性能及其机理

以草鱼鱼鳞为原料制备生物吸附剂,比较了该鱼鳞吸附剂对几种不同化学染料的吸附效果,研究了其对刚果红的最佳吸附条件及相关影响因素,并通过吸附动力学和吸附热力学分析以及吸附前后的红外光谱分析,初步探讨了鱼鳞吸附剂对刚果红的吸附机理。实验结果表明,鱼鳞吸附剂对含有磺酸根基团的染料具有良好的吸附能力,其对不同染料的吸附效果依次为:刚果红＞胭脂红＞亮蓝＞日落黄＞亚甲基蓝;在室温条件下,鱼鳞吸附剂吸附刚果红的最佳吸附条件为:吸附剂用量0.2 g/L、体系pH 7.0、刚果红初始浓度为14 μg/mL;吸附热力学和动力学分析表明,鱼鳞吸附剂对刚果红的吸附是一种以不可逆方式自发进行的吸热过程,准二级动力学模型可以较好地反映这种动态吸附行为。红外光谱分析表明,鱼鳞吸附剂中参与吸附刚果红的功能性官能团主要包括氨基、羧基、磷酸根和碳酸根等,其分别归属于鱼鳞中的蛋白质和羟基磷灰石类成分。

Absorption ability and mechanism of fish scales from grass carp to Congo red

In this study,the sorbent was prepared from fish scale of grass carp and the absorption capability of this sorbent to different chemical dyes was determined.At the same time,the best absorption conditions and the absorption mechanism of this sorbent were studied by use of kinetic and thermodynamic analysis and FTIR assay.The results show that the adsorbent from fish scales has good absorption capacity for the dyes which have sulfonic acid group and the order of adsorbent capabilities to different dyes is:Congo red>carmine>brilliant blue>sunset yellow>methylene blue.While the temperature was 25 ℃,the absorbent dosages was 0.2 g/L,the potential of hydrogen was 7,the concentration of Congo red was 14 μg/mL,and the effect of fish scales sorbent on Congo red was the best.The quasi secondary dynamic model could reflect the isothermal absorption dynamics of different dosage of fish scales sorbent.The results of kinetic and thermodynamic analysis showed that the endothermic process of this adsorbent was spontaneous and irreversible.The infrared analysis showed that the functional groups of fish scales on Congo red absorption were composed of amino,carboxyl,phosphate groups and so on,which belonged to protein and hydroxyapatite of fish scales.