铝酸钠溶液中草酸钠溶解度计算模型的建立及应用.pdf

第24卷第10期
中国有色金属学报
2014年10
Volume 24 Number 10
The Chinese ournal of Nonferrous Metals
October 2014
文章编号:1004-0609(2014)10-2652-06
铝酸钠溶液中草酸钠溶解度计算模型的建立及应用
李小斌,2,徐旺2,张玉通2,齐天责,2
(1.中南大学治金与环境学院,长沙410083
2.中南大学难治有色金属资源高效利用国家工程实验室,长沙410083
摘要:应用 Bromley方程,结合草酸钠溶解热力学理论及其在水溶液、氢氧化溶液中的溶解度数据,得出草
酸钠的 Bromley参数为-0.045,并以此为基础建立铝酸钠溶液中草酸钠的溶解度计算模型。应用该模型计算纯铝
酸钠溶液体系中草酸钠的溶解度,结果与文献数据吻合较好。在此基础上,模拟计算了拜耳法氧化铝生产过程中
草酸钠平衡浓度的变化规律。结果表明:碱浓度越高、温度越低、苛性比越高,铝酸钠溶液中草酸钠平衡浓度越
低;铝酸钠溶液体系中,碳酸钠、硫酸钠对草酸钠溶解度的影响很小。这些结果可以解释草酸钠在生产氧化铝过
程中的积累和析出规律,有助于生产过程铝酸钠溶液中草酸钠含暈的控制。
关键词:草酸钠;溶解度;计算模型;铝酸钠溶液
中图分类号:TF821
文献标志码:A
Establishment and application of calculation model of
sodium oxalate solubility in sodium aluminate solution
LI Xiao-bin, 2, XU Wang2, ZHANG Yu-tong,, Q] Tian-gui, 2
(1. School of Metallurgy and Environment, Central South University, Changsha 410083, China
2, National Engineering Laboratory for Efficient Utilization of Refractory Non-ferrous Metals Resources,
Central South University, Changsha 410083, China
Abstract: The calculation model of sodium oxalates solubility in sodium aluminate solution was established by Bromle
equation with the solubility values of sodium oxalate in the aqueous and sodium hydroxide solution, and Bromley
parameter of sodium oxalate calculated by this model is-0.045. Using this calculation model, the solubility values of
sodium oxalate in sodium aluminate solution were calculated and a high degree of agreement can be reached compared
with the data in literatures. On this basis, the equilibrium concentration values of sodium oxalate in Bayer liquors were
calculated. The results show that, the higher the alkali concentration and caustic ratio are or the lower the temperature is,
the lower the equilibrium concentration of sodium oxalate is. The concentration of sodium carbonate or sodium sulfate
has little effect on the solubility of sodium oxalate. These results can explain the law of the accumulation and
precipitation of sodium oxalate in alumina production process, and contribute to controlling the concentration of sodium
oxalate in the process
Key words: sodium oxalate; solubility; calculation model; sodium aluminate solution
拜耳法氧化铝生产过程中,多种有机物通过氧化稳定运行和产品质量?,尤其使晶种分解得到的产品
分解并与NaOH反应生成草酸钠,草酸钠随着溶液的严重细化。在铝酸钠溶液中加入有机添加剂,以抑制
循环而不断积累,直至过饱和析出,从而影响生产的草酸根对种分过程产生的不利影响是工业上常用的手
收稿日期:2014-03-05;修订日期:2014-07-10
通倍作者:齐天贵,讲师,博士;电话:0731-88877830:E-mail:qtgcsu@163.com