Green Global
Foundation   Journal
...an emerging window for scientific research and publication across the globe

EVALUATION OF TEA BIOMASS FOR NICKEL CONTAMINATED WASTE WATER TREATMENT (Pages : 7 - 16)

Industrial effluents loaded with heavy metals are a cause of health hazard to human and other forms of life as a result of their discharge into water bodies. Conventional methods for the removal of heavy metals from waste water are however, often expensive having inadequate efficiencies at low metal concentrations. These constraints have caused the search for alternative technologies for sequestering metals to cost effective and environmentally acceptable level. Waste tea biomass which contain active sites for metal adsorption was evaluated for the treatment of nickel contaminated waste water. Biosorption experiment was performed in a rotary shaker at 180rpm at different reaction time of 20, 30, 40, 120 and 180 minutes. Five levels of nickel solutions were also prepared (10g L-1 , 20g L-1 , 30g L-1 and 50g L-1 ) at different pH (2,3,5, and 7) in order to determine the best pH for optimum nickel adsorption. The generated data were fitted into Elovic, parabolic diffusion, intra-particle diffusion, pseudo-first order and pseudo-second order kinetic models. Langmuir and Freundlich equations were also used to determine which of the models best describe the adsorption process. Result showed that, Langmuir and Freundlich equations gave good fit into the adsorption of nickel on the biomass with correlation coefficients of determination (R2 ) 0.999 and 0.998 respectively. The biomass adsorbed 98% of 10gL-1 nickel (II) solution while 30% of 50g L-1 nickel solution was adsorbed. Adsorption was found to increase as pH of solution increased up to 5 after which adsorption decreased. Pseudo second order best described the adsorption reaction rate with R2 value of 0.99. It can then be concluded that, the best solution pH for optimal removal of nickel from waste water is pH 5 and the appropriate metal concentration for nickel contaminated waste waster treatment is 10gL-1. Hence, it is recommended that, industrial effluent contaminated with nickel Download