Factorial experimental design for biosorption of iron and zinc using Typha domingensis phytomass

Typha domingensis phytomass was used as a biosorbent for metal ions removal from wastewater. A full 23 factorial design of experiments was used to obtain the best conditions of biosorption of Fe3+ and Zn2+ from water solutions. The three factors considered were temperature, pH, and biosorbent dosage. Two levels for each factor were used; pH (2.5 and 6.0), temperature (25 and 45 °C), and phytomass loading weight (0.5 and 1 g/50 ml). Batch experiments were carried out using 50 ml solutions containing 10 mg/l Fe3+ and 4 mg/l Zn2+ simulating the concentration of those metals in a real wastewater effluent. The removal percentages of iron and zinc after 120 min of contact time were then evaluated. The results were analyzed statistically using the Minitab 15 statistical software to determine the most important factors affecting the metals removal efficiency. The pH was found to be the most significant factor for the two studied metal ions.