Thermodynamics of Zn(Ⅱ)-NH3-NH4Cl-H2O system①
(Department of Metallurgy Science and Engineering, Central South University,
Changsha 410083, P.R.China)
Changsha 410083, P.R.China)
Abstract: According to the principles of simultaneous equilibrium and aqueous electronic charge neutrality, the complex equilibrium of zinc-ammonia and zinc-chloride in the system of Zn(Ⅱ)-NH3-NH4Cl-H2O existing zinc oxide has been studied. The solubility rule and high solubility area of zinc oxide were discovered in the system whose zinc solubility is higher than other two ammonium systems, ammonium sulfate and ammonium carbonate. The absolute average error between the experimental values and the theoretically calculated values of zinc equilibrium concentration is 10.77% in aqueous solution of ammonia and ammonium chloride except in pure ammonium chloride solution. It shows that the critical stability constants and the thermodynamic data are believable.
Key words: zinc; ammonia; complex; thermodynamic