Equilibrium and kinetic modeling on the removal of Reactive Red 120 using positively charged Hydrilla verticillata

In the present study, the effect of biosorbent dosage (0.2-1.6 g/L), pH (1-7) and initial dye concentration (30-90 mg/L) on Reactive Red 120 removal from an aqueous medium using Hydrilla verticillata biomass has been investigated. The equilibrium sorption isotherms have been analyzed by the Freundlich and Langmuir models. The Freundlich isotherms have the highest coefficient of determination. The effect of temperature on the biosoption capacity of sorbent was studied. The kinetic data of the biosorption was analyzed using the Pseudo-first order and Pseudo-second order kinetic models. The data showed that the Pseudo-second order equation was the more appropriate. The optimum conditions for maximum removal of Reactive Red 120 dye from an aqueous solution was observed as 0.2 g/L for biosorbent dosage, as two for pH value, as 90 mg/L for initial dye concentration and as 50 °C for temperature.