无机盐杂质对铝酸钠溶液晶种分解率的影响  

Influence of Inorganic Salt Impurities on Seed Decomposition Rate in Sodium Aluminate Solutions

作　　者：彭志宏[1] 邓永春[1] 周秋生[1] 刘桂华[1] 李小斌[1] 

机构地区：[1]中南大学冶金科学与工程学院,湖南长沙410083

出　　处：《矿冶工程》2010年第1期57-61,共5页Mining and Metallurgical Engineering

基　　金：国家重点基础研究发展规划项目(2005CB6237-02)

摘　　要：采用对比实验法,研究了不同类型、不同浓度的无机盐杂质对铝酸钠溶液晶种分解的影响,并探讨了其影响机理。结果表明,铝酸钠溶液中氯化钠、碳酸钠、硫酸钠等杂质的存在对晶种分解会产生不利影响,当NaC l浓度大于10 g/L、Na2Os浓度大于5g/L、Na2Oc浓度大于10 g/L时,均将对铝酸钠溶液晶种分解产生明显的抑制作用。无机盐杂质的存在会影响铝酸钠溶液中氢氧化铝颗粒表面的Zeta电位值,使Zeta电位变得更负,不利于氢氧化铝晶体颗粒对铝酸根离子的吸附,从而对铝酸钠溶液晶种分解产生抑制作用。无机盐杂质使铝酸钠溶液表面张力增大,也阻碍铝酸根离子在晶体表面的吸附,对晶种分解产生不利影响。Influence of different concentrations and types of inorganic salt impurities on seed decomposition in synthetic sodium aluminate solutions has been studied by comparison tests, and the influence mechanisms are discussed. Results show that the seed decomposition could be affected by the presence of sodium chloride, sodium sulfate and sodium carbonate in the solutions, in which the seed decomposition would be significantly restrained when the concentrations of NaCl, Na2Os and Na2Oc are more than 10, 5 and 10 g/L respectively. The impurities can make the zeta potential of aluminum hydroxide particles in the solutions more negative, which would cause difficulty for the crystal particles to adsorb aluminate anions. Moreover, the impurities can bring about increase of the solution surface tension, which would do harm to adsorption of the aluminate anions on the crystal surface and produce a negative influence on crystallization of the aluminum hydroxide from the solutions.

关 键 词：拜耳法 铝酸钠溶液 晶种分解 无机盐 机理 

分 类 号：TF821[冶金工程—有色金属冶金]