The Adsorption of Cadmium(II) and Nickel(II) Ions Using Iminodiacetic Acid Chelating Resins

• Main Authors: Po-Cheng Hsu, 許伯誠
• Other Authors: 蔡德華
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/2aw6dh

碩士 === 國立臺北科技大學 === 化學工程研究所 === 100 === In this study, we examined the adsorption characteristics of Cadmium(II) and Nickel(II) onto Purolite S930Plus from aqueous solution in respect to changes in metal concentration, resin gram and temperature of the reaction environment, while changes in pH value of solutions were observed. The study showed that the lengths of time to achieve adsorption balance for the Cadmium(II) single composition solution system and the Nickel(II) single composition solution system are 600 minutes and 960 minutes respectively, whereas for the binary composition solution system of Cadmium(II) and Nickel(II), it is 1440 minutes. In the binary composition solution system, the selectivity of resin toward Nickel(II) is higher than its selectivity for Cadmium(II). The adsorption amount per resin gram increased as the temperature of the reaction environment rose, but decreased along with rises in resin grams. The results also showed that for the adsorption of both metals, the Freundlich isotherm model fitted the equilibrium data best, compared with the Langmuir isotherm and the BET isotherm models. In addition, we also calculated the thermodynamic functions, enthalpy (ΔH°), free energy (ΔG°), and entropy (ΔS°) changes of adsorption for each metal ion. Single system(Cd2+)：ΔH°= 8824～11089(J/mol),ΔG°= -5226～-7432 (J/mol),ΔS°= 20.36～57.65 (J/mol．K). Single system(Ni2+)：ΔH°=5125～13405(J/mol),ΔG°= -5790～-9773 (J/mol),ΔS°= 39.98～68.06(J/mol．K). Binary system(Cd2+)：ΔH°=13100～13314(J/mol),ΔG°= -5741～-8013(J/mol),ΔS°=21.24～73.31(J/mol．K). Binary system(Ni2+)：ΔH°=9454～11961(J/mol),ΔG°= -5972～-11066(J/mol),ΔS°=54.02～69.45(J/mol．K).