金属络阴离子在笼形聚氨肟树脂上的吸附行为

Adsorption properties of cage polyamidoxime adsorbents for metal complex anions

研究了Ce（NO3）_6~3-、VO_3^-、Cr2O_7~2-、CrO_4~2-、MoO_4~2-、WO_4~2-、MnO_4^-、Fe（CN）_6~2-、Fe（CN）_6~3-、和PtCl_6~2-等金属络阴离子在笼形聚氨肟树脂（CAO）上的吸附行为。发现Ce（NO3）-6~2-离子在强酸性介质中不被CAO树脂吸附但被还原为Ce3+。其它金属络阴离子被酸处理笼形聚氨肟树脂（ACAO）所吸附，吸附容量顺序是：MnO_4^-＞Fe（CN）_6~2-＞Cr2O_7~2-＞MoO_4~2-＞PtCl_6~2-＞CrO_4~2-＞VO_3^-＞Fe（CN）_6~3-＞WO_4~2-减处理笼形聚氨肟树脂（BCAO）不吸附CrO_4~2-离子，但可吸附Cr2O_7~2-、MnO_4~2-和PtCl_6^-等离子。吸附容量顺序：MnO_4^-＞Cr2O_7~2-＞PtCl_6~2-根据吸附动力学研究结果，认为ACAO树脂通过离聚体的离子场对外来给阴离子进行多层吸附，但金属络阴离子在BCAO树脂大分子场力作用下在树脂表面形成单吸附层。

Adsorption ability of cage polyamidoxime adsorbents (CAO) for the metal comolex anions such as Ce(NO3), VO, Cr2O, CrO, MoO, WO, MnO, Fe (CN),Fe (CN3) and PtCl was investigated. It was found that the Ce(NO3) anion does not adsorbed byCAO adsorbents at pH<1, but it is able to be reduced to Ce (Ⅲ ) under the same conditions. Other metal complex anions can be adsorbed by acid-treated cage polyamidoxime adsorbent (ACAO) in neutral solution, the order of adsorption capacity is MnO > Fe(CN ) >Cr2O >MoO >PtCl > CrO>VO> Fe(CN3) >WO.Excepting CrO anion, all the metal complex anionslisted above can be adsorbed by alkali-treated cage polyamidoxime adsorbent (BCAO) in the following order: MnO4>Cr2O> PtCl. Experimental evidence of adsorptive ki netics is presented that the metal complex anions uptaken by ACAO adsorbent is related to the electrostatic field of the ionomer and approaches the multilayer sorption, however, the metal complex anions attracted by the weaker macromolecular field of BCAO adsorbent result in the formatiom of monolayer sorption.