金属基树脂对含盐氨氮废水的吸附研究

Adsorption of saline ammonia-nitrogen wastewater by metal-based resin

盐分的存在使得氨氮废水的处理难度大大增加。在含盐条件下,利用负载过渡金属(Co^(2+)、Ni^(2+)、Cu^(2+)、Zn^(2+))的D001树脂和D751树脂对氨氮废水进行了吸附实验。与负载前树脂相比,金属基D001(D751)树脂比表面积增大,且吸附氨氮后树脂形貌更为有序;5次循环吸附氨氮后各金属离子依然牢固地固定在树脂上,说明金属基D001(D751)树脂稳定性较好。吸附动力学研究发现,金属基D001(D751)树脂对氨氮的吸附过程符合准二级动力学,且在吸附氨氮过程中吸附剂与吸附质之间存在由电子转移或共享产生的化学作用力。对金属基树脂对含盐氨氮废水吸附机理进行了剖析,结果表明金属基树脂与溶液中的氨氮存在配位吸附作用,通过配位共价键键合形成配体络合物。

The existence of salt makes it much more difficult to treat ammonia nitrogen wastewater.The adsorption of ammonia nitrogen wastewater by D001 resin and D751 resin,which were loaded with transition metals(Co^(2+),Ni^(2+),Cu^(2+),Zn^(2+)),was carried out under salt-containing conditions.Compared with the resin before loading,the specific surface areas of the metal base D001(D751)resin increase and the resin morphology is more orderly after the adsorption of ammonia nitrogen.After the absorption of ammonia nitrogen for five cycles,the metal ions are still firmly fixed on the resin,indication that metal base D001(D751)resin has good stability.It is found by adsorption kinetic study that the adsorption process of ammonia nitrogen by metal-based D001(D751)resin complies with the quasi-secondary dynamics.Meanwhile,there are chemical forces generated by electron transfer or sharing between the adsorbent and the adsorbate in the adsorption process of ammonia nitrogen.The adsorption mechanism of metal-based resin on salt-containing ammonia-nitrogen wastewater was analyzed,showing that there is coordination adsorption between the metal-based resin and the ammonia nitrogen in the solution,which forms a ligand complex by coordination covalent bonds.