采用有核一步法,通过控制AB2型单体和三羟甲基丙烷的摩尔比,一次性投料反应合成端羟基超支化聚合物(HPAE)。利用红外光谱对HPAE的配位结构进行表征,并研究了其在水溶液中对Fe^3+吸附过程的热力学和动力学特征。结果表明,在293~313K条件下,HPAE对Fe^3+的吸附量为50.8-84mg/g时,Langmuir等温方程呈现较好的拟合,且HPAE对Fe^3+的吸附量随Fe^3+浓度和温度的升高而增加;不同温度下的ΔH〉0、ΔG〈0、ΔS〉0,表明该吸附反应是吸热、自发、熵增的过程;动力学研究表明该吸附过程符合准二级动力学方程,吸附反应速率是液膜扩散和颗粒内扩散共同作用的结果。
Using one step method with core,the molar ratio of AB2 type molecule was controlled,and hyperbranched polymer with terminal hydroxyl(HPAE) was synthesized by disposable batch feeding.The coordination structure of HPAE was characterized by FTIR,and the thermodynamics and kinetics characteristics that HPAE adsorbed Fe^3+ in aqueous solution were studied.The results showed that in the condition of 293~313K and the adsorption of HPAE on Fe^3+ was 50.8~84mg/g,the fitting of Langmuir isotherm equation was good,and the adsorption of Fe^3+ on HPAE was increase following the concentration of Fe^3+ and temperature.ΔH0,ΔG0 and ΔS0 at different temperature,it indicated that the adsorption reaction was endothermic and spontaneous,and its entropy was increase.The kinetics showed that the adsorption process accorded with two order reaction kinetics equation.The adsorption reaction was the result of an effect on liquid film diffusion and intra-particle diffusion.