在硝酸系統下模擬砷化鎵溶液,嘗試以萃取劑D2EHPA和陰離子交換樹脂分離鎵和砷二種物質,並探討其萃取方程式和吸附模式。然後將實驗數據,應用於實際分離純化廠商所提供的砷化鎵下腳料。 研究結果表明,鎵在硝酸系統、pH 0 ~ 1的情況下,是以三價陽離子的形式存於水溶液當中,其萃取方程式如下所示: 〖"Ga" 〗^"3+" " + 2 " ("H" _"2" "R" _"2" ) ‾" ⇋ " (〖"GaR" 〗_"3" "(HR)" ) ‾" + " 〖"3H" 〗^"+" 〖"Ga" 〗^"3+" " + " "5" /"2" ("H" _"2" "R" _"2" ) ‾" ⇋ " (〖"GaR" 〗_"3" 〖"(HR)" 〗_"2" ) ‾" + " 〖"3H" 〗^"+" 以陰離子交換樹脂做為吸附劑,去除水溶液所含的砷,探討樹脂克數及初始砷濃度對於吸附行為的影響,結果顯示該吸附行為符合Langmuir等溫吸附模式。 最後對砷化鎵下腳料進行回收,廢料經硝酸溶解後,以D2EHPA萃取鎵,再經反萃、中和沉澱和鍛燒等程序,可得回收產物β-Ga_2 O_3。再以陰離子交換樹脂進行砷的吸附,經脫附和硫化沉澱等程序,可得回收產物As_2 S_3。
Try to separate Gallium and Arsenic by extractant D2EHPA and anion exchange resin from GaAs solution simulated on the nitric acid system, and discuss its extraction equation and the adsorption model. Then, use these experimental data to separate and rarefy the GaAs waste solid. The results show that, Gallium presents in the form of trivalent cation when pH 0 ~ 1 in the nitric acid system. The extraction equations are that: 〖"Ga" 〗^"3+" " + 2 " ("H" _"2" "R" _"2" ) ‾" ⇋ " (〖"GaR" 〗_"3" "(HR)" ) ‾" + " 〖"3H" 〗^"+" 〖"Ga" 〗^"3+" " + " "5" /"2" ("H" _"2" "R" _"2" ) ‾" ⇋ " (〖"GaR" 〗_"3" 〖"(HR)" 〗_"2" ) ‾" + " 〖"3H" 〗^"+" Remove Arsenic by the anion exchange resin and discuss the effects of the weight of resin and the initial concentration of As, and the adsorption behavior is in accordance with the Langmuir isothermal adsorption model. Finally, about the recovery of the GaAs waste, we could obtain the products of Ga_2 O_3 and As_2 S_3.