Aqueous Phase Removal of Tartrazine

In this study, published articles on the adsorptive removal of tartrazine from the aqueous phase were reviewed. Adsorbents sustaining both intercalating and photodegradation characteristics were also assessed. Besides collating available information on adsorbents employed for tartrazine removal, experimental conditions (solution temperature, pH, dosage, initial concentration, and agitation period) relating to the adsorptive removal of tartrazine were discussed. Deduction from kinetic, isotherms and thermodynamics data acquired from different adsorbents were assessed. Granular activated carbon and chitosan adsorbents had the least and highest tartrazine removal capacity. Lower solution pH majorly favoured the adsorption of tartrazine. On the other hand, increased dosage, contact time, initial concentration, and solution temperature generally enhanced the adsorptive uptake of tartrazine. Pseudo-second-order kinetics model was observed to typically describe the kinetic data. Freundlich and Langmuir isotherm models were popularly observed to best describe the tartrazine adsorption equilibrium. The uptake of tartrazine was generally spontaneous with the exception of a few nanocomposites. Meanwhile, π-π stacking, hydrogen bonding, Van der Waals forces and electrostatic interactions were proposed as possible mechanisms for the adsorption of tartrazine from wastewater. Adsorbents demonstrated good regeneration tendency with NaOH. Hence, it was concluded that the batch adsorption technique is economically viable and should be scaled up for industrial applications. Meanwhile, future work on tartrazine adsorption should employ real wastewater samples, regenerate adsorbents for reuse, design and execute a pilot scale assessment, employ column adsorption technique and formulate policy to regulate effluent discharge.