ABSTRACT:
The citrus limonium peel has been known as the potential aid for the adsorption of various metals. The biosorbent prepared from the citrus limonium peel is practically recognized for the rapid evacuation and fast biosorption of chromium ions from the waste water effluents. Batch studies were performed to evaluate the biosorption characteristics of Citrus limonium peel for of Cr+6 from aqueous solutions at various process parameters like pH (1-9), metal ion concentration (20-100 mg/L), the mass of the biosorbent (0.1-0.5 g), average particle size (75-212 Mesh) and solution temperature (303-333 K) at a maximum equilibrium agitation time of 75 minutes in an orbital shaker at 180 RPM. The obtained exploratory results were taken into consideration, the maximum evacuation of chromium onto Citrus limonium peel as biosorbent by 91.81 %. Optimized the biosorption efficiency using Central Composite Design (CCD) at pH = 5.08, Initial concentration 23.3 mg/L, the mass of the biosorbent is 0.35 grams and temperature of the metal solution is 307.09. Experimentation led above optimum conditions, the value of 2.93 % deviation is obtained with proposed value. Adsorption isothermal data were easily interpreted by Freundlich, Langmuir, Temkin and Dubinin–Radushkevich (D–R), a Freundlich model with maximum biosorption capacity of 19.6 mg/g of chromium ions on Citrus limonium peel. The kinetic data were appropriately equipped with the pseudo-second-order kinetic model.