A new nonlinear temperature programmed desorption(TPD)model was proposed. This model was different from the classical TPD model in that the re-adsorption phenomenon of the adsorbate was taken into account. TPD experiments were carried out to determinate the TPD spectra of dibenzofuran desorbed from the Norit RB1

Monolith and Chemviron activated carbons. Based on these experimental spectra the activation energy of dibenzofuran desorption on the three activated carbons was estimated by using the classical TPD model and the new nonlinear TPD model. The results showed that the activation energy calculated by the classical TPD was 8％—12％ higher than that calculated by the nonlinear TPD model

indicating the remarkable effect of the re-adsorption phenomenon on desorption activated energy.