摘要
利用Langmuir等温方程研究了阴离子染料酸性四号橙、酸性耐光橙和二甲酚橙在壳聚糖上的吸附规律,线性回归法统计出吸附等温线参数.结果显示,吸附容量依赖于pH.在酸性范围内,氨基质子化,聚合链带正电荷,壳聚糖对染料的吸附主要是离子交换吸附,也存在范德华力和氢键型吸附.对二甲酚橙,角系数为0.726 L/mg,温度升高,脱附作用增强,壳聚糖吸附容量降低.酸性耐光橙吸附焓ΔH值为-10.9 kJ/mol,酸性四号橙为-28.9 kJ/mol,壳聚糖对染料的吸附是一放热过程.
The absorption of anionic dyes orange Ⅳ, orange G and xylenol orange on chitin was studied with employing the Langmuir isotherm. The absorption parameters were determined by utilizing various linear regressions of the isotherm. The results showed that the absorption capacity is dependent on pH. In acid pH, the polymer amino groups are protonated and the polymer chain is positively charged, with a predominance of absorption through ion exchange. Van der Waals absorption as well as absorption through hydrogen bonding is also likely to occur to some extent. For xylenol orange, the linear regression was found, with an angular coefficient of 0. 726 L/mg. The temperature increases, absorption capacity by chitin reduces due to the enhancement of the desorption step in the mechanism. △H values of - 10.9 kJ/mol for orange G and - 28.9 kJ/mol for orange Ⅳ prove the physical nature of the absorntion by these dyes on the chitin surface.
出处
《北华大学学报(自然科学版)》
CAS
2009年第6期490-493,共4页
Journal of Beihua University(Natural Science)
基金
衡阳市科技发展计划资助项目(2007KJ028)