Green chemistry requires concepts and industrial ecology using natural systems to rid industrial water flow from heavy metals, which effects badly on health and environment. For this purpose, the changes in coefficient of distribution of mercury has been studied in system with two phases, liquid (water contaminated with mercury) - solid (metal pyrite) correlation of the following factors: Time of mixing phases, size of the developed steel, change the values of pH, concentration of elemental mercury, the concentration of calcium as a competitor to the occupation of sites available on the solid phase, the ratio V / M presents the water phase size on the mass of phase, which reflects the remaining time of water phase in the solid phase. The results show that pyrite can be proposed as safe environmental solution for purification of water phase of mercury, after controlling for some operation transactions.