PP-g-AO织物制备及其铀酰离子吸附性能

Preparation of PP-g-AO fabric and its adsorption properties of uranyl ions

为了有效处理含铀废水以防止其污染环境,通过对聚丙烯织物进行预辐射接枝引入环氧基团,待1,3-丙二胺开环后,再通过氮杂迈克尔加成和胺肟化制备了PP-g-AO织物;利用扫描电镜、红外光谱和热重分析对PP-g-AO织物进行了表征,研究了pH值、铀酰离子平衡浓度、反应时间和反应温度对PP-g-AO织物的吸附性能的影响,并进行了等温吸附模型、动力学和热力学分析。结果表明:PP-g-AO织物的吸附容量随铀酰离子平衡浓度的增大而增大;在pH为6时,吸附容量达到峰值;当反应时间为4 h时,吸附容量接近饱和;PP-g-AO织物吸附铀酰离子过程更符合Langmuir模型,属于单分子层吸附;吸附过程较符合准二级动力学模型,是由材料表面活性位点数目和结构共同决定的;吸附过程为自发的吸热过程,提高温度有利于吸附铀酰离子。

In order to effectively treat the wastewater containing uranium to prevent its pollution to the environment,PP-g-AO fabric was prepared by introducing the epoxy group through the pre-radiation grafting of polypropylene fabric,and after the ring was opened by 1,3-propylene diamine,the PP-g-AO fabric was prepared by the addition of aza-Mike and amine oxime.PP-g-AO fabric was characterized by scanning electron microscopy,infrared spectroscopy and thermogravimetric analysis.The effects of pH value,uranyl ion equilibrium concentration,reaction time and temperature on the adsorption properties of PP-g-AO fabric were studied.The results show that the adsorption capacity of PP-g-AO fabric increases with the increase of uranyl ion equilibrium concentration.When the pH value is 6,the adsorption capacity reaches the peak.When the reaction time is 4 h,the adsorption capacity isclose to saturation.The uranyl ion adsorption process of PP-g-AO fabric is more consistent with the Langmuir model and belongs to single molecular layer adsorption.The adsorption process conforms to the quasi-secondary kinetic model,which is determined by the number and structure of active sites on the surface of the materialsurface.The adsorption process is a spontaneous endothermic process.Increasing the temperature is beneficial to the adsorption of uranyl ions.