Dye adsorption on unburned carbon: kinetics and equilibrium.
Dye adsorption on unburned carbon: kinetics and equilibrium.
复制标题
DOI：
10.1016/j.jhazmat.2005.05.049
复制
发表时间：
2005-11
影响因子：
13.6
通讯作者：
Shaobin Wang;Huiting Li
中科院分区：
文献类型：
--
作者：
Shaobin Wang;Huiting Li
飞灰中的未燃碳是煤燃烧的重要副产物。从粉煤灰中分离出未燃炭，并将其作为一种低成本的吸附剂用于碱性染料罗丹明B的吸附。吸附等温线和吸附动力学进行了研究，采用间歇实验。结果表明，染料的吸附量与溶液的初始浓度、pH值和温度有关。吸附等温线可用Langmuir模型描述，在30、40和50°C下对罗丹明B的吸附量分别为9.7×10−5、1.14×10−4和1.5×10−4molg−1。采用准一级和二级动力学模型对吸附过程进行了拟合。结果表明，吸附过程符合准二级动力学模型。热力学计算表明，吸附为吸热反应，ΔH°为25kJmol−1。
Unburned carbon in fly ash is an important by-product from coal combustion. In this investigation, unburned carbon has been separated from fly ash and been employed as a low cost adsorbent for a basic dye adsorption (Rhodamine B) in aqueous solution. Adsorption isotherm and kinetics of adsorption have been investigated using batch experiments. It is found that dye adsorption capacity depends on initial concentration, pH of solution, and temperature. The adsorption isotherm can be described by Langmuir model and the adsorption capacity of Rhodamine B at 30, 40, and 50°C can reach 9.7×10−5, 1.14×10−4, and 1.5×10−4molg−1, respectively. The pseudo first- and second-order kinetic models have been employed to fit the dynamic adsorption. It is found that the dynamic adsorption follows the pseudo second-order model. Thermodynamic calculations indicate that the adsorption is endothermic reaction with ΔH° at 25kJmol−1.