包埋类脂的吸附剂制备及吸附POPs性能

用丙酮作溶剂将三油酸甘油酯分散到醋酸纤维(CA)基体中,采用悬浮聚合的方法制备出了一种兼具亲水性,又能高倍富集持久性有机污染物的球形复合吸附剂。通过对分散剂的种类及其用量、悬浮介质的种类及其用量的研究,获得了球形复合吸附剂的最佳合成路线与工艺.球形吸附剂粒径为1～2mm。通过荧光分析和电镜扫描分析,表明三油酸甘油酯已被包埋到醋酸纤维基体中,并得到了均匀分散。采用七氯、狄氏剂、异狄氏剂、灭蚁灵为代表性的持久性有机污染物(POPs)。动力学吸附实验表明,当初始浓度为1μg/L时,在快速吸附阶段,溶液中80%的氯、狄氏剂、异狄氏剂可得到有效去除,但并没有达到吸附平衡。快速吸附完后,还在持续地进行慢速吸附。而对于灭蚁灵,吸附速度远远低于其他几种POPs。实验证明了吸附速度不仅与辛醇/水系数有关,而且还与有机污染物的分子结构有关。

Preparation of Triolein/CA Sorbent and Its Adsorption for POPs in Water

After triolein was dispersed into cellulose acetate (CA)matrix by using acetone as solvent,a novel hydrophilic composite sorbent that could effectively accumulate persistent organic pollutants (POPs) in water was developed by the method of suspension polymerization. Different dispersants and suspended medium and their dosage were studied. Diameter of spherical sorbent was about 1～2mm. Sorbent structure analyzed by scanning electron microscope indicated that triolein was perfectly dispersed into CA matrix. Taking heptachlor,diedrin,endrin and metrix as representative compounds of POPs, kinetic experiments results indicated that about 80% POPs could be removed in fast adsorption stage,but adsorptive equilibrium was not obtained and slow adsorption still carried through. Adsorptive rate for metrix was far lower than other POPs. Kinetic experiments identified that adsorptive rate was not only related to octanol/water coefficient but related to molecular structure of POPs.