竹炭对硝基苯吸附的热力学与动力学参数

摘要

The adsorption property, thermodynamic parameters and kinetic parameters of nitrobenzene with bamboo-charcoal were studied in this paper. The result shows that adsorption equilibrium time is 540 rain and the bamboo-charcoal shows high adsorption ability for nitrobenzene at the pH of 5.6. Langmuir isotherm model is well obeyed. The studying kinetics shows that the adsorption kinetics of bamboo-charcoal on nitrobenzene can be described by pseudo first-order kinetics. The adsorption 298 K. The studying thermodynamic shows that the adsorption process of hamboo-charcoal on nitrobenzene is an exothermic adsorbate from solution to adsorbent surface is a spontaneous process.%研究竹炭对硝基苯的吸附性能及吸附的热力学与动力学参数.吸附试验表明:竹炭对硝基苯吸附的最佳酸度为pH=5.6;吸附平衡时间为540 min;竹炭对硝基苯的吸附遵守Langmuir吸附等温方程.动力学研究表明:竹炭对硝基苯的吸附动力学拟用准一级动力学进行描述,298 K时,吸附的速率常数为k298=2.42×10-4s-1,吸附活化能Ea=23.5 kJ·mol-1.热力学研究表明:竹炭对硝基苯的吸附是放热过程,吸附热为△H=-16.8 kJ·mol-1;△S=37.9 J·K-1 mol-1;△G=-28.1 kJ·mol-1,负的吸附自由能变化值体现了吸附质从溶液到吸附剂表面的吸附过程是自发过程.