巯基活性碳富集剂对重金属离子的吸附特性

CHARACTERISTICS OF SULFHYDRYL-CONTAINING ADSORBENT BASED ON ACTIVE CARBON

从热力学、动力学及XPS3个方面讨论了巯基活性碳富集剂对重金属离子的吸附机理。结果表明富集剂的吸附过程以化学吸附为主。外表面,内表面对Cu^(2+)的吸附率分别为19%,81%;Pb^(2+)为6%,94%,对Zn^(2+)为17%,83%,而吸附Cd^(2+)完全由内扩散所控制。被吸附的Cu^(2+)还将进一步还原为Cu^o。

The absorption mechanism of a novel separation absorbent containing sulfhydryl group has been studied in terms of thermodynamics and kinetics. The results indicate that the adsorbent is able to absorb heavy metal ions:Cu^(2+) ,Pb^(2+) ,Cd^(2+), and Zn^(2+). The predominant process of the adsorption is a chemical adsorption. The amount of the adsorption on the outer and internal surface of the adsorbent is 19% and 81% for Cu^(2+);6% and 94% for Pb^(2+); 17% and 83% for Zn^(2+), respectively ; while the adsorption of Cd^(2+) is controlled only by internal diffusion. For Cd^(2+) only an outer surface adsorption was observed. The XPS results show that Cd^(2+) , Pb^(2+) and Zn^(2+) are adsorbed and thus enriched by the novel separation adsorbent. The Cu^(2+) adsorbed may be then reduced to Cu^o.