Department of Chemical and Materials Engineering, National Kaohsiung University of Applied Sciences, 415 Chien Kung Road, Kaohsiung 807, Taiwan.
Water Sci Technol. 2012;65(3):490-5. doi: 10.2166/wst.2012.878.
In this study, C.I. Reactive Red 2 (RR2) was removed from aqueous solutions by chitin. Exactly how the RR2 concentration, chitin dosage, pH, and temperature affected adsorption of RR2 by chitin was then determined. After reaction for 120 min, the amount of 10 and 20 mg/L RR2 absorbed onto chitin was 5.7 and 7.5 mg/g, respectively. The adsorption percentage increased from 56 to 94% when the chitin dosage was increased from 1.5 to 2.5 g/L. Experimental results indicated that the pseudo-second-order model best represents adsorption kinetics. Adsorption of RR2 increased as the temperature increased; however, it decreased with an increased pH. Experimental results further demonstrated that the Freundlich model is superior to the Langmuir model in fitting experimental isotherms. The ΔH° and ΔS° were 16.34 kJ/mol and 152.10 J/mol K, respectively. ΔH° suggested that adsorption of RR2 onto chitin was via physisorption.
在这项研究中，甲壳素去除了水溶液中的 C.I. 活性红 2（RR2）。然后确定 RR2 浓度、甲壳素用量、pH 值和温度如何影响 RR2 被甲壳素吸附。反应 120 分钟后，10 和 20 mg/L RR2 被甲壳素吸附的量分别为 5.7 和 7.5 mg/g。当甲壳素用量从 1.5 增加到 2.5 g/L 时，吸附百分比从 56%增加到 94%。实验结果表明，伪二阶模型最能代表吸附动力学。RR2 的吸附随着温度的升高而增加；然而，随着 pH 值的增加，吸附量减少。实验结果进一步表明，Freundlich 模型比 Langmuir 模型更适合拟合实验等温线。ΔH°和ΔS°分别为 16.34 kJ/mol 和 152.10 J/mol K。ΔH°表明 RR2 吸附到甲壳素上是通过物理吸附。
