Phenol adsorption in immobilized activated carbon with alginate gels

Calcium alginate-activated carbon composites were used for phenol adsorption from aqueous solutions. These composites were prepared by mixing different amounts of powdered activated carbon with a 3% (w/v) sodium alginate solution, and then dripping the mix into a calcium solution. Spherical beads were obtained with different amounts of powder-activated carbon immobilized inside the calcium alginate matrix. The adsorption on immobilized adsorbents modified the distribution equilibrium. A modified Langmuir equation was considered for analyzing adsorption isotherms and solid phase interactions. The kinetic of phenol adsorption on mixed gels is controlled by the diffusion of phenol in the particle over the gel phase, so the process can be described by one diffusional parameter: the effective diffusion coefficient of phenol in the gel phase.