The separation of valuable metals from copper based alloys has important implications for treatment of byproducts from the ferrous and nonferrous metallurgical processes as well as for treatment of various copper scraps. To investigate the distribution coefficients of copper, cobalt, and nickel between L₁ and L₂ phase, some fundamental experiments on the metal solvent extraction process were conducted using liquid iron-tin-lead and iron-tin-silicon alloys as solvents. The purpose of these experiments was to investigate a pyrometallurgical process to separate directly cobalt and nickel from liquid copper based alloys or to remove preferentially the copper component from the alloys. The distribution coefficients of cobalt for both solvent systems represented very small values, suggesting the suitability of these solvents for the separation of cobalt from various kinds of copper based alloys. On the other hand, the distribution coefficients for both nickel and copper were not largely different.