The evolution of effective diffusion coefficients D eff of 13 different impurities in molten tellurium versus temperature T was studied. A new hyperbolic expression D eff = f (T ) for these impurities was established for effective segregation coefficients K eff 1 and for temperatures within the range 730 • K-925 • K. Experimental values of K eff determined by zone melting process were used to calculate a series of 4 effective diffusion coefficients D eff , at four different temperatures, for each impurity. These experimental results of D eff were fitted with the new expression of D eff = f (T ) to confirm its validity. The diffusion mechanism of 13 impurities at the solid-liquid interface was then investigated under our previous experimental conditions (velocity v of interface, the starting concentration C 0 , and number n of passes). These investigations confirmed that the temperature increase of tellurium molten zone was not convenient to reach an optimal purification by zone melting process.