摘要
本研究選用HCl、 HNO3及H2SO4三種單酸及其混酸進行實際光電業鉻蝕刻廢液處理所產出鈰污泥酸提之研究。實驗結果顯示，不論使用單酸或混酸進行酸提，定溫70℃下，較佳之反應時間為60分鐘。在70℃、酸提60分鐘及固液比(鈰污泥重/酸體積)50 g/L下，以4N HCl為酸提液時，Ce(質量)溶出率達96.7%，速率常數為0.104 min-1；若改用4N HNO3，則其Ce溶出率相似(96.3%)，速率常數為0.081 min-1。H2SO4較不適用於鈰污泥之鈰酸提。使用體積比1：1而HCl及HNO3單酸濃度皆為4N混酸(A酸)為酸提液時，在溫度70℃及固液比50 g/L下，反應時間至60分鐘，其Ce溶出率已達100%，因此，混酸比單酸有助於Ce之溶出；在相同條件下，將混酸中兩種單酸之濃度皆提高至8N (B酸)、甚至於12N (C酸)，無助於增加Ce溶出率。對混酸於定溫70℃酸提鈰污泥之鈰而言，在固液比10~100 g/L範圍內，混酸A及混酸B較佳之固液比均為50 g/L，混酸C則為30 g/L，其速率常數為分別為0.067、0.109及0.136 min-1。本研究可做為光電業鉻蝕刻廢液處理產出鈰污泥鈰回收之實際應用參考。 關鍵字：鈰回收、鈰污泥、酸提（酸溶）、鉻蝕刻廢液、TFT-LCD。
並列摘要
This study investigates the cerium acid-leaching of cerium-containing sludge generated from practical spent thin-film transistor liquid-crystal display (TFT-LCD) Cr-etching solutions using HCl, HNO3 and H2SO4 and their mixtures. Despite the use of single or mixed acids, the best leaching time for Ce leaching was 60 min at 70°C. When operated under the solid/liquid (sludge weight/acid volume) ratio of 50 g/L at 70°C for 60 min, the 4 N HCl and 4 N HNO3 exhibited similar Ce (mass) leaching ratios (96.7% and 96.3%, respectively) (with rate constants of 0.104 and 0.081 min-1, respectively). It is not suitable for H2SO4 to be used for the acid-leaching of Ce from the sludge. Under the same leaching conditions, the use of 4 N HCl/HNO3 (v/v = 1:1) (A acid) two-acid mixture achieved 100% Ce leaching, so the two-acid mixture is better than the single acids for Ce leaching form the sludge; however, using higher concentrations (8 and 12 N) of two-acid mixtures (B acid and C acid, respectively) did not raise the Ce leaching ratio. At 70°C, the best solid/liquid ratio for A, B, and C acids were 50, 50, and 30 g/L, respectively (with rate constants of 0.067, 0.109, and 0.136 min-1, respectively) within the tested range of 10–100 g/L. The data obtained from this study are useful for the Ce recovery from cerium-containing sludge generated from practical spent TFT-LCD Cr-etching solutions. Keywords: Ce recovery; Ce sludge; Acid-leaching; Spent Cr-etching solution; TFT-LCD