氯甲基化聚苯乙烯-间苯二胺树脂对Pb(Ⅱ)的吸附

Adsorption studies of Pb( Ⅱ) on chelating resin of chloromethylated copolymer of styrene-divinylbenzene modified by m-phenylenediamine

聚氯甲基化苯乙烯(PS-CH2Cl)和间苯二胺(MPA)在相转移催化剂的作用下,合成聚氯甲基化苯乙烯间苯二胺树脂(PS-CH2-MPA),研究了PS-CH2-MPA对Pb(Ⅱ)的吸附性能,通过改变溶液的p H值、吸附温度、Pb(Ⅱ)的初始浓度、吸附时间等因素来探究树脂PS-CH2-MPA对Pb(Ⅱ)的吸附效果,实验结果表明,酸性范围内,吸附量随着p H的增加而增加,p H=6时,吸附效果最佳;PS-CH2-MPA对Pb(Ⅱ)的吸附速率较快,t=60min即可基本达到平衡;吸附过程能较好的吻合Freundlich等温吸附模型,且是放热过程,高温不利于吸附;对PS-CH2-MPA进行吸脱附实验,其吸附性能并未下降,是一种可以重复使用的吸附剂,所有结果表明PS-CH2-MPA在吸附Pb(Ⅱ)方面有着广阔的应用前景.

A novel chelating material （PS-CH2Cl-MPA） was prepared by reacting chloromethylated copolymer of styrene-divinylbenzene （PS-CH2Cl） with m-phenylenediamine （MPA） in the presence of phase transfer catalyst. Adsorption activities of PS-CH2-MPA for Pb （Ⅱ） from sewage were investigated with regard to contact time, pH, the initial Pb （Ⅱ） concentration and temperature. The results revealed that the adsorption capacity of PS-CH2-MPA was effected by the acidity of solution, maximum adsorption was observed at pH=5;Initial rate was very rapid and gradually slowed down, it can be inferred that the equilibrium reached when t = 60min; The adsorption data followed Freundlich model. Moreover, lower temperature was preferable for adsorption since it was exothermic;The adsorption for re-adsorption of PS-CH2-MPA has no degradation, the adsorbent can be reused; Therefore, PS-CH2-MPA is an effective adsorbent for the removal of Pb （Ⅱ） from sewage.