A Study on Equilibria of the Quaternary System Na+ K+//Br-, SO42--H2O at 323 K

作者：Sang Shi-Hua^*; Sun Ming-Liang; Li Heng; Zhang Xiao; Zhang Kai-Jie

来源：Chinese Journal of Inorganic Chemistry, 2011, 27(5): 845-849.

• salt-water system
• phase equilibrium
• solubility
• glaserite
• sulfate

An experimental study on equilibria at 323 K in the quaternary system Na+, K+//Br-, SO42--H2O was done by isothermal equilibrium method. The equilibrium solubilities and densities of the solution were determined experimentally.Using the experimental data, the equilibrium phase diagrams were plotted, respectively. The experimental results of the equilibria show that the double salt Na2SO4 center dot 3K(2)SO(4) forms in the quaternary system Na+, K+//Br, SO42--H2O at 323 K. In the phase diagram,the quaternary system at 323 K has three invariant points, seven univariant curves, and five crystallization fields corresponding to NaBr center dot 2H(2)O, NaSO4, K2SO4, KBr and Na2SO4 center dot 3K(2)SO(4). The double salt Na2SO4 center dot 3K(2)SO(4) and sulfates (Na2SO4 and K2SO4) have larger crystallization fields, but bromides (NaBr center dot 2H(2)O and KBr) have smaller crystallization fields. The experimental results of Na+, K+//Cl-, SO42-H2O quaternary system were compared with the quaternary system Na+,K+//Br-, SO42--H2O at 323 K. It is also found that bromide has the salting-out effect on sulfates in the quaternary system Na+,K+//Br-, SO42--H2O at 323 K.

• 出版日期2011-5
• 单位成都理工大学