氨基化丙烯酸基磁性树脂对Cu^2＋的吸附特性

以N，N-亚甲基双丙烯酰胺为交联剂，利用悬浮聚合法制备聚丙烯酸甲酯磁性树脂（RM），并经乙二胺改性后制得一种新型磁性吸附剂（RMA）。采用差热／热重分析（DTA／TGA）以及红外光谱等对其进行了表征，并考察了它对Cu^2＋的吸附性能。结果表明，RMA树脂粒径30～60btm，FesOt质量分数为6．7％，对Cu^2＋的吸附等温线符合Langmuir模型，饱和吸附容量2．13mmol／g，高于未改性树脂（RM，1．15mmol／g）。吸附动力学可用拟二级反应模型拟合。热力学分析表明RMA对Cu^2＋的吸附过程能自发进行，焓变为-17．88kJ／mol，熵变为-2．06J／（mol·K），Bibbs自由能为-17．26～-17．19kJ／mol。吸附剂用1mol／LHCl洗脱再生，脱附率高于97％。

Adsorption Properties of Amine Chelating Acrylate-Based Magnetic Resin Toward Cu~(2+) Ions

Magnetic poly （acrylate methyl ester） resin （RM） was prepared by suspension polymerization using N, N＇- methylenebisacrylamide as a crosslinker. Then RM was modified with ethylenediamine to give a novel amine- chelating magnetic resin（RMA）. This adsorbent was characterized by thermal analysis （DTA/TGA） and FT--IR. The adsorption behaviour of the adsorbent toward Cu^2＋ ions was investigated. The results show that the diameter of RMA is 30-60μm and the mass fraction of Fe3O4 is 6.7%. The isotherm adsorption data obeyed the Langmuir model. In the aspect of maximum adsorptiom capacity, RMA displayed higher （2. 13 mmol/g） for Cu^2＋ than that of RM （1. 15 mmol/g）. Kinetics studies indicate that the adsorption reaction followed the pseudo-- second order kinetics. Thermodynamic analysis indicates that the adsorption process was spontaneous, and that the value of enthalpy changes was --17.88 kJ/mol, the entropy changes was - 2.06 J/（mol · K） and the Gibbs free energy was -- 17.26 - -- 17.19 kJ/mol. Regeneration of the adsorbent was achieved using 1 mol/L HC1 with the desorption ratio of more than 97%.