【摘要】 研究了胺型腰果酚醛树脂对Ni 2+、Co2+、Zn2+的吸附行为,考察了溶液pH值、吸附时间、初始离子浓度、温度等条件的影响以及吸附动力学和热力学特征,并经结构分析(FTIR、XPS、DSC-TG)探讨了其吸附机理。结果表明,树脂对Ni 2+、Co2+、Zn2+均有较高的吸附量,吸附选择性Ni 2+>Co2+>Zn2+;溶液pH值为5.5时吸附效果最佳,100min内吸附基本平衡,提高浓度和温度均有利于吸附的进行;吸附动力学特征可用Lagergren二级吸附动力学方程描述;吸附热力学特征符合Langmuir吸附等温方程,吸附为吸热熵增的自发过程;推测其吸附机理是树脂中胺基、羟基与金属离子发生较强的配位作用和较弱的离子交换作用的化学吸附为主;吸附后的树脂用稀硝酸处理后易脱附再生。更多还原

【Abstract】 Adsorption behaviors of Ni 2+,Co2+,and Zn2+ in cardanol aldehyde-amine resin were investigated.Then effects of pH values,initial concentration of metal ions,adsorption time and adsorption temperature were studied,and adsorption kinetics-thermodynamics characteristics were also discussed.Moreover,its adsorption mechanisms of metal ions in water were studied by structure analysis using FTIR,XPS,and DSC-TG.The experimental results indicated that cardanol aldehyde-amine resin had high adsorption capacity of metal ions.The order of adsorption selectivity for metal ions was Ni 2+>Co2+>Zn2+.Specifically,the adsorption capacities of metal ions reached an optimum at pH 5.5,adsorption equilibriums were attained within 100 minutes,and the increasing concentration and temperature were advantageous to adsorption process.Additionally,the adsorption kinetics characteristics could be well described using the pseudo-second-order kinetic model.Further results showed that the adsorption thermodynamics characteristics was well fitted with the langmuir isotherm.And thermodynamic studies revealed that the adsorption processes of metal ions were endothermic(ΔH>0),entropy favored(ΔS>0),and spontaneous(ΔG <0)in nature.The adsorption mechanisms of metal ions could be mainly attributed to chemical adsorption,that is,metal ions would coordinate strongly with amino group or hydroxyl group,and exchange weakly with amino group in resin.In addition,the desorption and regeneration processes were easy to carry out using a dilute nitric acid solution.更多还原