| dc.description.abstract | Background: The sources of phenolics pollutants in water are mainly chemical industries and pharmaceutical. They are harmful and toxic even at modest concentrations. Despite substantial achievements for water treatment using adsorption, there is need to search for bio-adsorbent which is user-friendly, ecofriendly and efficient. Materials and Methods: Characterization of raw and modified cornstarch, was done using Fourier Transform Infrared (FT-IR) spectrophotometer. The modulated cornstarch was used in the removal batch experiment on model solutions. The efficiency of modified cornstarch in hydroquinone and 2-naphthol removal at different batch adsorption parameters at room temperature were investigated. Pseudo first and second order kinetic models were used to determine mechanisms involved in both chemisorption and physisorption processes. The Langmuir and Freundlich isotherms were used to determine adsorption capacity of the aminated corn-starch (ACS). Results: The FT-IR spectrum of the ACS showed strong broad band with increased intensity at 3295.44cm-1 which confirmed C-N stretch of amine group and N-H stretch of amine salt were anchored. Batch studies revealed that maximum removal of phenolic compounds (PCs) was realized at a contact time of 10 mins, pH of 5.0-6.0 and constant temperature of 25±1 ℃ for the hydroquinone and 2-naphthol. The uptake increased with increase in the dosage of ACS and initial concentration of phenolics. The rate of adsorption process was best described by the pseudo–second order kinetic model (k2). The maximum uptake of PCs occurred at initial concentration of 10 ppm and then plateaued. The batch experimental data obtained best fitted into the Langmuir isotherm, and monolayer adsorption capacities of 4.585 and 5.048 mg/g for hydroquinone and 2-naphthol respectively. Conclusion: According to this study, the adsorption process was monolayer and homogenous in nature. These adsorption capacities were relatively higher than many reported processes, thus indicating that the ACS an effective adsorbent for removal of hydroquinone and 2-naphthol from aqueous solutions. | en_US |
