Application of periwinkle shell ash as photocatalyst in the heterogeneous photocatalytic degradation of aniline in aqueous solution

Periwinkle shell ash (psa) was used as a photocatalyst in the photocatalytic degradation of aniline in aqueous solution. the effects of contact time,initial aniline concentration,psa dosage,ph and hydrogen peroxide (h2o2) on the process were investigated. the results show that maximum photocatalytic degradation efficiency was obtained at a contact time of 100 minutes,initial aniline concentration of 50 mg/l,psa dosage of 2 g/l and ph of 8. the addition of h2o2 improved the photocatalytic degradation efficiency to almost 100 percent. the adsorption equilibrium was well described by the langmuir isotherm equation (r2=0.951). the kinetics of the process was well described by the pseudo first order and langmuir-hinshelwood kinetic models while the diffusion mechanism was modelled by the intra particle diffusion model (r2>0.90).