(1. 北京科技大學(xué) 材料科學(xué)與工程學(xué)院，北京 100083；
2. 中國(guó)科學(xué)院 過程工程研究所 濕法冶金清潔生產(chǎn)技術(shù)國(guó)家工程實(shí)驗(yàn)室，北京 100190；
3. 中國(guó)科學(xué)院 過程工程研究所 綠色過程與工程院重點(diǎn)實(shí)驗(yàn)室，北京 100190)
摘 要: 主要從固相法和液相法兩個(gè)方面介紹鉻鹽生產(chǎn)工藝中鋁雜質(zhì)的脫除方法，固相法重點(diǎn)介紹無鈣焙燒法，無鈣焙燒熟料中含鋁固相產(chǎn)物有鐵鎂礦(Mg(Fe,Al)2O4)、鋁硅酸鈉(NaAlSiO4)和鋁硅酸鎂鈉(Na4MgAl2Si3O12)。同時(shí)，根據(jù)鉻礦成分的不同，添加含硅或含鋁原料，控制SiO2和Al2O3摩爾比，使鉻鐵礦中的鋁和硅在無鈣焙燒過程中轉(zhuǎn)化成為鋁硅酸鈉和鋁硅酸鎂鈉。鉻酸鹽熟料浸出過程中，液相中鋁化合物主要是鋁酸鹽。液相法脫除鋁雜質(zhì)與體系的堿濃度密切相關(guān)。低堿濃度時(shí)，碳分法有利于得到鉻酸鹽夾帶少、易過濾的氫氧化鋁；高堿濃度時(shí)，首先進(jìn)行萃取脫堿，降低溶液中堿/鋁比例，然后采用種分法得到氫氧化鋁沉淀。綜述了各種除鋁方法的特點(diǎn)，并探討了除鋁方法的發(fā)展方向。
關(guān)鍵字: 鉻鹽；氫氧化鋁；固相法；液相法
（1. School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China;
2. National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology,
Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China;
3. Key Laboratory of Green Process and Engineering, Institute of Process Engineering,
Chinese Academy of Sciences, Beijing 100190, China）
Abstract:The solid phase method and liquid phase method for aluminum removal in the chromium compound production were reviewed. The special emphasis was placed on lime free roasting process. Magnesioferrite (Mg(Fe,Al)2O4), sodium aluminosilicate (NaAlSiO4), silicic acid, aluminum magnesium sodium salt(Na4MgAl2Si3O12) are the major phases of aluminum containing compound. Certain amounts of silica dioxide or aluminum oxide and such additives, depending on the chromium containing material, are added to control the molar ratio of SiO2 and Al2O3 in order to form aluminum containing compound. The liquid phase methods is relative to the alkali concentration. For decomposition of aluminates in low alkali solution, carbonate process benefit for the production of easy filterable aluminum hydroxide with little content of chromate. For decomposition of aluminates in high alkali solution, aluminum hydroxide is obtained by seed composition following by extraction of great amount of alkali metal hydroxide and decrease of alkali/aluminum ratio. Finally, the problems and development of aluminum removal process were pointed out and analyzed.
Key words: chromium compound; aluminium hydroxide; solid phase method; liquid phase method
