摘要
测定分析蒙脱石的孔隙结构及化学组成,采用批量平衡实验研究了改性后蒙脱石对硝基苯(NB)的吸附特性,并从动力学及热力学角度探讨了NB的强化吸附作用机理。研究结果表明,吸附过程符合伪二级动力学方程,反应经过快速吸附、减速吸附和平衡吸附3个阶段,12 h达到吸附平衡。K+-蒙脱石对NB的吸附符合Henry方程,吸附过程主要由分配作用所致,随着改性的K+浓度越高,离子强度增强,EDA作用效果显著。另外,K+-蒙脱石对NB的吸附是一个放热过程,在303～323 K范围内,反应的吉布斯自由能变小,吸附反应为自发过程。
Pore structure and chemical composition of montmorillonite were determined and analyzed in this study. A batch adsorption study was carried out to investigate the properties, kinetics and thermodynamics of adsorption process of NB on KC1 modified montmorillonite. The research results show that the adsorption followed pseudo-second-order kinetics, including rapid adsorption, slow adsorption and equilibrium adsorption. After adsorbing for twelve hours, the adsorption reactions can reach equilibrium. The experimental data display excellent fitting with the Henry equation, resulted from NB partition into KC1 modified montmorillonite. With the higher concentration of K＋, the ionic strength increases and the effect of EDA is remarkable The adsorption of NB is exothermic in nature and is accompanied with increasing entropy and decreasing Gibbs energy in the temperature range from 303 to＇323 K, suggesting that the adsorption behaviour may be the spontaneous nature of the interaction without requiring large activation elaergies of adsorption.
出处
《矿物学报》
CAS
CSCD
北大核心
2012年第4期555-562,共8页
Acta Mineralogica Sinica
基金
国家自然科学基金项目(批准号:41072034
40773080)
广东省自然科学基金项目(1015106
3101000028)
关键词
硝基苯
蒙脱石
改性
吸附
nitrobenzene
montmorillonite
modified
adsorption
