本研究使用螯合樹脂Purolite S930Plus為固體吸附劑,吸附交換水溶液中的重金屬鈷(Ⅱ)和錳(Ⅱ)。藉由改變金屬濃度、樹脂克數及反應溫度並觀察水溶液pH值變化,探討其不同變數下吸附平衡的特性。 實驗顯示,鈷(Ⅱ)、錳(Ⅱ)的單成分溶液系統及鈷(Ⅱ)與錳(Ⅱ)共存的雙成分溶液系統的吸附平衡時間大約在600分鐘;且鈷(Ⅱ)與錳(Ⅱ)金屬共存的雙成分溶液系統下,發現樹脂對鈷(Ⅱ)的選擇性高於錳(Ⅱ)。而反應溫度上升,平衡吸附量隨著增加,但溶液中樹脂克數增加,平衡吸附量卻隨著降低。經離子交換平衡的數據以Freundlich、Langmuir 、BET等溫模式分析下,實驗結果較符合Freundlich等溫模式。最後由金屬離子吸附結果求得焓(ΔH°)、Gibbs能(ΔG°)、熵(ΔS°)值之熱力學參數。 在單成份硫酸鹽水溶液Co2+:ΔH°= 4521∼16231 (J/mol),ΔG°= -6777∼-8383 (J/mol),ΔS°= 40.03∼81.82 (J/mol*K)。 在單成份硫酸鹽水溶液Mn2+:ΔH°= 14546∼30104 (J/mol),ΔG°= -5440∼-7033 (J/mol),ΔS°= 70.91∼126.55 (J/mol*K)。 在雙成份硫酸鹽水溶液Co2+:ΔH°= 6060∼15641 (J/mol),ΔG°= -4280∼-6627 (J/mol),ΔS°= 35.90∼77.32 (J/mol*K)。 在雙成份硫酸鹽水溶液Mn2+:ΔH°= 14915∼19409 (J/mol),ΔG°= -4895∼-6581 (J/mol),ΔS°= 68.84∼87.58 (J/mol*K)。
In this study, we examined the characteristics of adsorption equilibrium of Cobalt(II) and Manganese(II) onto Purolite S930Plus from aqueous solution in respect to changes in metal ion concentration, resin gram and temperature of the reaction environment, while changes in pH value of solutions were observed. This study showed that the durations of time to achieve adsorption equilibrium for Cobalt(II) single composition solution system, Manganese(II) single composition solution system and binary composition solution system of Cobalt(II) and Manganese(II) are 600 minutes. In binary composition solution system, the resin exhibited a higher selectivity towards Cobalt(II) than Manganese(II) while the reaction achieved adsorption equilibrium. The amount of adsorption 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 metal ions, the Freundlich isotherm model fitted the equilibrium data best, compared with the Langmuir isotherm and the BET isotherm models. Finally, according to our results, we calculated the thermodynamic functions, enthalpy (ΔH°), Gibbs energy (ΔG°), and entropy (ΔS°) changes of each metal ion. Single sulfate solutions (Co2+):ΔH°= 4521∼16231 (J/mol),ΔG°= -6777∼-8383 (J/mol),ΔS°= 40.03∼81.82 (J/mol*K). Single sulfate solutions (Mn2+):ΔH°= 14546∼30104 (J/mol),ΔG°= -5440∼-7033 (J/mol),ΔS°= 70.91∼126.55 (J/mol*K). Binary sulfate solutions (Co2+):ΔH°= 6060∼15641 (J/mol),ΔG°= -4280∼-6627 (J/mol),ΔS°= 35.90∼77.32 (J/mol*K). Binary sulfate solutions (Mn2+):ΔH°= 14915∼19409 (J/mol),ΔG°= -4895∼-6581 (J/mol),ΔS°= 68.84∼87.58 (J/mol*K).