负载Cu^(2+)和Pb^(2+)的蒙脱石对结晶紫吸附的研究

Adsorption of Crystal Violet from Aqueous Solution on Cu^(2+)-and Pb^(2+)-Exchanged Montmorillonite

研究了振荡时间、吸附温度、溶液初始浓度、离子强度等因素对蒙脱石及负载Cu2+和Pb2+的蒙脱石吸附水溶液中结晶紫的影响.结果表明三种吸附剂对结晶紫染料吸附过程用准二级动力学模型拟合较好;蒙脱石对结晶紫的吸附采用Freundlich和Langmuir等温方程拟合效果均较好;染料的吸附量均随初始浓度和温度升高而增大,随离子强度的增大而减小;三种吸附剂对结晶紫的吸附是一个吸热、熵增、自发反应的过程.

In this study,three low-cost adsorbents,i.e.raw montmorillonite,Cu2＋-exchanged montmorillonite and Pb2＋-exchanged montmorillonite,were used to remove crystal violet from aqueous solutions.The effects of contact time,reaction temperature,initial dye concentrations and ionic strength were investigated in detail.The results showed that the process of the three adsorbents absorbing crystal violet followed the pseudo-second-order kinetic expressions,and the equilibrium data of montmorillonite well conformed to the Freundlich and Langmuir isotherm equations.The amount of crystal violet adsorbed increased with increasing initial dye concentration and temperature and decreased with increasing ionic strength.The adsorption of crystal violet on the adsorbents was endothermic,entropy increasing and spontaneous.