2.3. Mass transfer within the particle
The study of mass transfer within the particle was conducted to
determine that extraction of oil using soxhlet extractor or batch
reactor was not controlled or limited by the internal diffusion. Thiele
modulus was used to investigate the mass transfer within the
particle. To determine the value of Thiele modulus, effective diffusivity
(Deff), m2 s1 was calculated. Fick’s second law was used to
determine effective diffusivity by assuming Deff is constant with
the Y, yield at time, t and initial yield of the oil. Pinelo et al.
(2006) calculated effective diffusivity using following equation