羧基功能化交联共聚物微球的制备及其对亚甲基蓝的吸附性能

Preparation of Carboxyl-Functionalized Cross-linked Copolymer Microspheresand Their Adsorption Performances for Methylene Blue

以二乙烯苯(DVB)为交联剂,α-甲基苯乙烯(AMS)、马来酸酐(MAH)为单体,通过自稳定沉淀聚合原位制备α-甲基苯乙烯-马来酸酐交联共聚物微球(PAMSM),PAMSM与氢氧化钠反应后,转化为羧基功能化的交联共聚物微球(PAMSM-COOH)。对微球的结构进行了表征,研究了PAMSM-COOH微球对亚甲基蓝(MB)的吸附性能以及吸附剂循环利用效果。扫描式电子显微镜(SEM)分析表明,微球表面光滑,具有良好的球形度并且粒径均一。在MB初始质量浓度为200 mg/L,吸附剂用量为0.50 g/L,溶液pH值为7,吸附温度为313 K,吸附时间为4 h,PAMSM-COOH对MB的最大吸附容量为261 mg/g。微球吸附MB的动力学和等温数据分别符合拟二阶模型和Langmuir等温模型,微球吸附MB为自发进行的吸热过程。5次吸附-脱附循环实验表明微球对MB的去除率保持在85.0%以上。

Taking divinylbenzene(DVB)as the crosslinking agent,α-methylstyrene(AMS)and maleic anhydride(MAH)as monomers,cross-linked copolymer microspheres ofα-methyl styrene and maleic anhydride(PAMSMs)were designed and synthesized via in-situ self-stabilized precipitation polymerization.After reacting with sodium hydroxide,PAMSMs were transformed to carboxyl-functionlalized cross-linked copolymer microspheres(PAMSMs-COOH).The structures of the microspheres were characterized,the adsorption performance and adsorbent recycling experiment of PAMSMs-COOH for MB were investigated.The scanning electron microscope(SEM)analysis results show that the gloss microspheres with spherical morphology and narrow size distribution were obtained.The maximum adsorption capacity of PAMSMs-COOH for MB is up to 261 mg/g when the initial concentration of MB is 200 mg/L,the dosage of adsorbent is 0.50 g/L,the pH of solution is 7,the adsorption temperature is 313 K,and the reaction time is 4 h.The kinetics and isothermal data for the MB adsorption of microspheres respectively fit the pseudo-second-order model and Langmuir isothermal model.The adsorption of MB by PAMSMs-COOH is a spontaneous endothermic process.In addition,the removal rate of MB by PAMSMs-COOH remains more than 85.0%after five adsorption-desorption cycle experiments.