dichloromethane to n-heptane promotes the amine adducts formation and the modification of the interfacial equilibrium expression. For this reason, the structure of interfacial hydrophobic compound formed by pantothenic acid and aminic extractant was changed from HAE for dichloromethane to HAE2 for butyl acetate and HAE4 for n-heptane, respectively. When 1-octanol is added in the extraction system, due to an increase in organic phase polarity, the formation of aminic adducts is hindered, the structure of the interfacial complexes becoming HAE for dichloromethane and butyl acetate, and HAE2 for n-heptane.