β-CD/Al2O3/ATP复合材料对乙腈/正丙醇的吸附分离性能的影响

Study on the adsorption performance of β-CD/Al_2O_3/ATP composites for separation of acetonitrile and n-propanol

以β-CD/Al_2O_3/ATP复合材料为吸附剂,对乙腈和正丙醇体系进行静态和动态吸附实验,考察吸附条件对吸附分离性能的影响。实验结果显示,β-CD/Al_2O_3/ATP对体系具有较好的吸附效果。吸附时间的延长、吸附温度的降低和振荡速率的增大均使得静态饱和吸附量增大。利用Langmuir方程拟合吸附数据,呈现良好的线性关系。伪二级动力学方程较好地描述了乙腈和正丙醇在复合材料上的吸附动力学过程。动态吸附实验结果表明,适当地减小流速和增加柱高,有利于提高吸附分离效果。当流速为0.05L/min,柱高为10cm,β-CD/Al_2O_3/ATP复合材料对乙腈和正丙醇的饱和吸附量分别为182.6mg/g和69.76mg/g,乙腈的选择性达到0.73。

The static and dynamic adsorption experiments were carried out on the system of acetonitrile and n-propanol withβ-CD/Al2O3/ATP composites as adsorbent.The effect of the adsorption conditions on separation of the mixture was investigated.The result showed thatβ-CD/Al2O3/ATP composite had good adsorption separation effect to the system.The saturate adsorption capacity of the adsorbent was increased with the extension of adsorption time,the decreasing of adsorption temperature and the increasing of oscillation rate.The experimental data were fitted by the Langmuir equation,showing a good linear relationship.The kinetics of the adsorption of acetonitrile and n-propanol on the composite was well described by the pseudo secondary dynamics equation.The dynamic adsorption experiment showed that appropriate reduction of flow rate and increase of column height was beneficial to improve adsorption and separation efficiency.The saturate adsorption capacities of theβ-CD/Al2O3/ATP composite material for acetonitrile and n-propanol were182.6mg/g and69.76mg/g,respectively.The adsorptive selectivity of acetonitrile was0.73with the flow rate of0.05L/min and the column height of10cm.