活性炭吸附正丁烷动力学性能研究

Dynamic Analysis of Adsorption Behaviour of n-Butane in Granular Activated Carbon

研究了木质颗粒活性炭对正丁烷的吸附动力学,考察了吸附温度,正丁烷含量和正丁烷流量对活性炭吸附正丁烷过程的影响,并用准一级、准二级、Elovich和班厄姆4种动力学模型进行了拟合。结果表明:随着温度的升高活性炭对正丁烷的饱和吸附量降低,表明活性炭吸附正丁烷为放热反应;随着正丁烷体积分数的增大,吸附饱和时间不变,但正丁烷吸附量不断增大;正丁烷流量显著影响活性炭的吸附速率和吸附时间,但活性炭的饱和吸附量保持不变。在不同条件下班厄姆方程计算得到的相关系数R2均大于0.99,远高于其他3个动力学方程。因此,活性炭对正丁烷的吸附动力学行为遵循班厄姆动力学方程。

In this paper, wood-based granular activated carbon was used to study adsorption kinetics of n-butane. The effects of the adsorption temperature, the n-butane concentration and the n-butane flow rate were investigated. Then the date was fit by first order kinetics model, pseudo-second order kinetic model, Elovich kinetic model and Ben nahum kinetic model. The results showed that with the increasing of temperature, the adsorption amount of n-butane decreased. This indicated that adsorption of n- butane in activated carbon was an exothermic reaction. With the increasing of the n-butane concentration, n-butane adsorption performance also increased, but the adsorption time did not reduce. The flow rate of n-butane significantly influenced adsorption rate and adsorption time, but it had minor influence on the amount of n-butane adsorbed at equilibrium. It is also found that the R2 of Bangham equation is more than 0.99, which is much higher than the other three kinetic equation. Therefore the absorption kinetics is well satisfied with Bangham equation.