Determination of the diffusion coefficient and the activation energy of water desorption in IROKO wood (Chlorophora excelsa), during a conductive drying

Abstract

Five temperatures steps 40, 45, 50, 60 and 70 ° C in an approach that is both experimental and analytical helped the study of the kinetic drying of Iroko wood in calm atmosphere. Increasing the temperature significantly reduces drying time and shows a high absorption of water by heated air. The reduced moisture content of tropical biomaterial is evaluated, the model of Lahsasni, M.Kouhila Mr. Mahrouz and Kechaou is established in correlation with experimental points for subsequent exploitation, the solution of Fick’s second equation, allowed us to determine the diffusion coefficient of water in these experimental conditions whose values ranges from 1.66741x10-6 to 2.5924 x 10-6 x 10-6 (m2.s-1) depending on the applied temperatures. We also estimated the activation energy of water (20.23877 kJ / mol) during drying by analyzing the Arrhenius relation.