The determination of the surface heterogeneity of a solid is a difficult challenge. The present work proposes a method for the determination of the adsorption energy distribution functions (DF) directly computed from the chromatographic signal acquired at finite concentration conditions. The calculation of the DF calls on the extended Rudzinski and Jagiello’s solution method using discrete Fourier transforms to perform the multiple derivation of the distribution function for the condensation approximation. Because of the "ill-posed" character of the fundamental integral equation describing the adsorption on a heterogeneous surface, the good robustness of the method versus the experimental noise and the regularity of the data sampling was evidenced using a simulation program.