r2 = 0.8530.
The results showed that an effective diffusion coefficient relatively depended on drying temperature. The Arrhenius factor (D0) and the Ea =R values of 69.365 m2 /s and
2,246.601 kJ=kmol are insignificantly related to the initial moisture content ranging of 40–50 % dry basis (p < 0.05). Additionally, the effective diffusion coefficient of crumb rubber ranged from 1.0 109 to 2.15 105 m2 =s corresponding to drying temperatures between 40 and 150C, respectively.