The potential application of tomato seeds as low-cost industrial waste in the adsorption of organic dye molecules from colored effluents

The objective of current study is to investigate the tomato seeds (TSs) as a low-cost industrial waste material to be employed in the adsorption of two acid dyes (C.I. Acid Red 14 (AR14) and C.I. Acid Blue 92 (AB92)). In this regard, field emission scanning electron microscope images, Fourier transform infrared analysis, and determination of isoelectric pH were used to characterize the surface morphology, functional groups, and surface charge of TS, respectively. Initial dye concentration, pH, and adsorbent dosage were studied as the key parameters that affect the adsorption performance. The isotherm, kinetic, and thermodynamic parameters of removal process were determined. It was found that the experimental data had followed the Langmuir isotherm model. The pseudo-second-order kinetic model described the rate of adsorption process properly. Temperature variation of adsorption process indicated that the removal of AR14 and AB92 by TS was an exothermic and spontaneous procedure. Finally, the cost analysis demonstrated that TS can be suggested as an effective and eco-friendly biosorbent for the removal of organic dyes from colored textile wastewaters.