添加NaHCO_3强化铝酸钠溶液分解析出一水软铝石  

Boehmite precipitation from sodium aluminate solution intensified by adding NaHCO_3

作　　者：张娟[1,2] 王志[1] 郭占成[1,3] 

机构地区：[1]中国科学院过程工程研究所湿法冶金清洁生产技术国家工程实验室,北京100190 [2]中国科学院研究生院,北京100049 [3]北京科技大学循环与生态冶金教育部重点实验室,北京100083

出　　处：《中国有色金属学报》2010年第12期2445-2452,共8页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(50704030);中国科学院知识创新工程重要方向资助项目(KGCX2-YW-321-2)

摘　　要：在铝酸钠溶液中添加晶种制备一水软铝石的过程中,利用NaHCO3强化分解,研究一水软铝石晶种和NaHCO3添加方式对分解过程和产物的影响。结果表明:添加NaHCO3可以促进铝酸钠溶液的分解,使相同条件下的分解率提高3倍,晶种系数SR在0～1.0范围内铝酸钠溶液中NaHCO3添加量为151.2g/L时,分解率均高于80%。XRD和热重结果表明:添加NaHCO3时,分解产物为一水软铝石和三水铝石,SR越大或NaHCO3起始添加速率越慢,一水软铝石含量越高;当SR=1.0且NaHCO3添加速率为0.21g/(L·min)时,其含量可达到80.4%(质量分数);SR为0～1.0时,添加NaHCO3的产物是由一水软铝石和三水铝石相互镶嵌构成的附聚体,分解过程采用逐步加快NaHCO3添加速率的方式有利于得到砂状产物。Boehmite was precipitated with seeds from sodium aluminate solution intensified by NaHCO3,and the influence of seed ratio （SR） and adding NaHCO3 methods on precipitation process and products was studied. The results show that NaHCO3 can intensify the precipitation process of sodium aluminate solution and the precipitation ratio can be enhanced by 3 times under the same condition. When SR is 0-1.0 and the amount of adding NaHCO3 comes to 151.2 g/L,the precipitation ratio is all higher than 80%. XRD and TG results indicate that the products consist of boehmite and gibbsite,and increasing SR or slowing down the initial rate of adding NaHCO3 can improve the mass fraction of boehmite,which gets the value of 80.4% with SR=1.0 and adding amount of NaHCO3 of 0.21 g/（L·min）. The boehmite and gibbsite particles are inlaid together to form aggregates with SR of 0？1.0 and NaHCO3. The sand products can be got by gradually increasing the amount of adding NaHCO3 in the precipitation process.

关 键 词：NAHCO3 铝酸钠溶液 分解 一水软铝石 

分 类 号：TF111.3[冶金工程—冶金物理化学]