Optimization of Adsorption of 5-Amino-4-Hydroxy-3-[(E)-(5-Nitro-2-Thienyl) Dizenyl]-2,7- Naphthalenedisulfonic Acid Mono Sodium from Aqueous Solution Using Activated Telfairia Occidentalis Seed Waste.

Abstract

The potential of activated carbon, prepared from fluted pumpkin seed waste for the adsorption of an azo dye: 5-amino-4-hydroxy-3-[(E)-(5-nitro-2-thienyl)diazenyl]-2,7-naphthalenedisulfonic acid mono sodium, from aqueous solution was investigated. Chemical activation method was adopted for the preparation of the adsorbent, using ZnCl2 as the activating agent. The adsorbent prepared was characterized on the basis of activated carbon yield, ash content, iodine sorption capacity and surface area. The activated carbon yield was found to be 50.40%; ash content was 0.18%, iodine sorption capacity of 92.68% and a surface area of 625.00 m²/g. The effect of pH, adsorbent dose, initial dye concentration and contact time on removal efficiency of the dye by the adsorbent was studied. Full factorial design (FFD) of experiment was employed to optimize the adsorption process. The result obtained indicated that the optimum condition of pH 5.00, adsorbent dose of 0.10 g, initial dye concentration of 5.00 ppm and contact time of 20.00 minutes, gave 99.50% removal efficiency. This value obtained falls within the recommended value of ≥80% for good adsorbents. The experimental removal efficiency value of 99.50% observed was in good agreement with the value predicted of 99.94% by the FFD.