Response Surface Modeling and Optimization of Effective Parameters for Zn(II) Removal From Aqueous Solution Using Gracilaria Corticata

• Main Authors: Farah Assadian, Ali Niazi, Majid Ramezani
• Format: Article
• Language: English
• Published: Islamic Azad University 2020-07-01
• Series: Journal of Chemical Health Risks
• Subjects: biosorption; box-behnken design; equilibrium isotherms; gracilaria corticata, rsm; zn(ii)
• Online Access: http://www.jchr.org/article_674309_54fb929b36a364c554b91819b63c4dc7.pdf
• ISSN: 2251-6719; 2251-6727

Biosorption of Zn(II) from aqueous solution by biomass marine alga, namely <em>Gracilaria corticata</em> was investigated in this paper. Four independent variables, including initial zinc concentration (50-150 mg L^-1), initial solution pH (3-7), contact time (10-50 min), and biomass amount (1-2 g/100mL) were studied in the biosorption process. Optimization of the process conditions for maximizing Zn(II) removal from aqueous solutions by <em>Gracilaria corticata</em> was carried out using Box-Behnken design, including response surface methodology (RSM) based on 27 different experimental data. The optimal operating conditions for 95.0% removal of Zn(II) were as follows: initial zinc concentration of 100 mg L^-1, initial solution pH of 5, contact time of 30.5 min, and biomass amount of 2 g/100 mL. In addition, the equilibrium isotherms were described by investigation of Langmuir and Freundlich isotherms. The Freundlich adsorption isotherm model well matched the experimental data (R² = 0.981). The kinetic data fitted pseudo-second order model with a correlation coefficient of 0.9953. <em>Gracilaria corticata</em> was found to be well applicable for zinc removal based on the experimental results.