胺基修饰高交联聚苯乙烯微球对水中对硝基苯酚的吸附特性

Adsorption removal of p-nitrophenol from wastewater by aminated hyper-cross-linked polystyrene microsphere

通过“傅氏后交联+表面氨基化”的工艺路线制备出一种胺基修饰高交联聚苯乙烯微球A-HPM,考察了A-HPM对溶液中对硝基苯酚(PNP)的吸附特性。结果表明,A-HPM具有比表面积高、纳米孔结构与胺基官能团丰富等特点,能够通过微孔填充、π-π和酸碱作用协同吸附去除溶液中的PNP。溶液pH对A-HPM去除PNP的性能有较大影响,弱酸性条件下(pH为5~6)A-HPM对PNP的最大吸附量可达153.9 mg/g(初始质量浓度为200 mg/L)。A-HPM对PNP的吸附属于放热反应,且吸附性能不受溶液中共存离子的影响。动力学研究表明,A-HPM对PNP的吸附可在1200 min达到平衡。吸附饱和的A-HPM能够通过NaOH溶液进行高效再生,再生后A-HPM的吸附性能保持稳定,从而实现长期循环使用。

A new recyclable aminated hyper-cross-linked polystyrene microsphere(A-HPM)is synthesized for effective removal of p-nitrophenol(PNP)from wastewater.Possibly benefited from its unique structure of polystyrene matrix,sufficient aminated groups and high specific surface area,A-HPM can remove PNP from wastewater through the synergetic effect of micropore filling,π-πinteractions and acid-base interactions.PNP adsorption by A-HPM is a pH-dependent process with the maximum adsorption capacity of 153.88 mg·g-1under weak acid condition and an initial PNP concentration of 200 mg·L^(-1).The adsorption of PNP by A-HPM is an exothermic process,and the removal performance is not affected by the coexisting ions.Kinetic study indicates its adsorption equilibrium can be achieved within 1,200 min.The exhausted A-HPM can be effectively regenerated by sodium hydroxide solution,allowing for long-term cyclic utilization with constant adsorption performance.