Biosorption of Nickel from Electroplating Wastewater using Green Algae Volvox

Of all the forms of water pollution, heavy metal pollution is the most hazardous as the pollutant is present in mobilized form. The ability of green algae volvox to biosorb nickel ions was investigated in batch mode so that it may be applied for the treatment of industrial wastewaters. The batch studies provide significant information regarding biosorption of nickel on green algae volvox in terms of pH and biomass dose for maximum removal of Ni(II) from the aqueous solution. The studies indicated that volvox is an effective biosorbent for Ni(II) removal. The maximum biosorption capacity was found to be 35.71 mg Ni(II)/g at an algal dose of 1g/L in 60 min of contact time with initial Ni(II) concentration of 100 mg/L and optimum pH of 4. The equilibrium studies in batch systems were described by Thomas and Freundlich isotherms. Best fit was obtained for both the isotherm models. It was found that the adsorption equilibrium data fitted well to the Langmuir model. With the advantage of high metal biosorption capacity, the biomass of volvox has the potential to be used as an efficient and economic biosorbent material for the removal of chromium from electroplating industrial wastewater.