摘要
主要从固相法和液相法两个方面介绍铬盐生产工艺中铝杂质的脱除方法,固相法重点介绍无钙焙烧法,无钙焙烧熟料中含铝固相产物有铁镁矿(Mg(Fe,Al)2O4)、铝硅酸钠(NaAlSiO4)和铝硅酸镁钠(Na4MgAl2Si3O12)。同时,根据铬矿成分的不同,添加含硅或含铝原料,控制SiO2和Al2O3摩尔比,使铬铁矿中的铝和硅在无钙焙烧过程中转化成为铝硅酸钠和铝硅酸镁钠。铬酸盐熟料浸出过程中,液相中铝化合物主要是铝酸盐。液相法脱除铝杂质与体系的碱浓度密切相关。低碱浓度时,碳分法有利于得到铬酸盐夹带少、易过滤的氢氧化铝;高碱浓度时,首先进行萃取脱碱,降低溶液中碱/铝比例,然后采用种分法得到氢氧化铝沉淀。综述了各种除铝方法的特点,并探讨了除铝方法的发展方向。
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.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2013年第6期1712-1722,共11页
The Chinese Journal of Nonferrous Metals
基金
国家杰出青年科学基金资助项目(51125018)
国家"十二五"科技支撑计划课题(2011BAC06B07)
国家高技术研究发展计划资助项目(2011AA060704)
关键词
铬盐
氢氧化铝
固相法
液相法
chromium compound
aluminium hydroxide
solid phase method
liquid phase method
