Diffusional mass transfer model for the adsorption of food dyes on chitosan films

- The adsorption of food dyes on chitosan films was studied by a diffusional model.
- The proposed model agreed very well with the experimental curves.
- The surface diffusion coefficient ranged from 0.41 × 10−14 to 22.90 × 10−14 m2 s−1.
- The surface diffusion was the rate limiting step.