高效微波辐射制备Fe-MSB对磷的吸附

Adsorption of Phosphorus Using Fe-MSB Prepared by Efficient Microwave Irradiation

采用高效微波辐射法,以Fe_2(SO_4)_3为改性剂对钠基膨润土进行改性,制得硫酸铁改性钠基膨润土(Ferric sulfate modified sodium bentonite, Fe-MSB)。通过对基本结构和形貌进行表征后,分析试样对吸附剂的吸附性能,探讨反应条件对Fe-MSB吸附磷的影响,运用吸附动力学和热力学对吸附过程进行分析。结果表明:改性后钠基膨润土的吸附性能得到明显提高;当Fe-MSB投加量为20g/L、初始pH为6、温度为303K和振荡时间为120min时,制得的Fe-MSB对磷的吸附效果最佳,磷的去除率高达98.72%;Fe-MSB吸附磷过程用准二级动力学方程表达时相关性最好;吸附规律符合Langmuir等温吸附方程,且Fe-MSB对磷的吸附以化学吸附为主,其吸附过程是一个自发进行、吸热、不可逆的过程。

In order to prepare environmentally friendly phosphorus adsorption materials and explore phosphorus adsorption law,ferric sulfate modified sodium bentonite (Fe-MSB)was prepared using Fez (SO4)3 andsodium bentonite by efficient microwave irradiation method.The product as the adsorbents was characterized in terms of structure and morphology before the investigation.The influence of reaction conditions on Fe-MSB adsorption of phosphorus was first studied.Adsorption kinetics and thermodynamics were employed to analyze the adsorption process.The results showed that adsorption capacity of Fe-MSB is obviously enhanced.The phosphorus adsorption efficiency is 98.72% under the optimal conditions with Fe-MSB dosage of 20g/L,pH of 6,temperature of 303K and reaction time of 120min.An experimental kinetic equation for the adsorption of phosphorus by Fe-MSB was obtained and could be well described by the pseudo-second-order kinetic model.The adsorption behavior accords well to the Langmuir isotherm equation. Moreover,the phosphorus adsorption by the Fe-MSB is mainly chemically adsorbed,spontaneous, endothermic,and irreversible.