Distribution of Silver Thiourea Complexes in Thiourea Leaching Solution

The dependence diagrams of mole fractions of the silver thiourea complexes on thiourea concentration are presented based on the calculation results of thermodynamic equilibrium principle.The main silver thiourea complexes in the acidic thiourea leaching solution are in the forms of [Ag(TU) ]+,[Ag(TU) 2 ]+,[Ag(TU) 3 ]+and [Ag(TU) 4 ]+.Silver ions and thiourea mainly form [Ag(TU) 3 ]+and [Ag(TU) 4 ]+in the solution with 0.066 mol / L thiourea and 0.000 19 mol / L silver ions,whose mole fractions are 0.727 8 and 0.237 5 respectively,with [Ag(TU) 3 ]+being the dominant species;Silver ions and thiourea also mainly form [Ag(TU) 3 ]+and [Ag(TU) 4 ]+in the solution with 0.66 mol / L thiourea and 0.097 2 mol / L silver ions,but the mole fractions of them are respectively 0.392 4 and 0.603 7,with [Ag(TU) 4 ]+being the dominant species.