Optimization of preparation of activated carbon from Ricinus communis leaves by microwave-Assisted zinc chloride chemical activation: Competitive adsorption of Ni 2+ ions from aqueous solution

The preparation of activated carbon (ac) from ricinus communis leaves was investigated in this paper. orthogonal array experimental design method was used to optimize the preparation of ac using microwave assisted zinc chloride. optimized parameters were radiation power of 100 w,radiation time of 8 min,concentration of zinc chloride of 30 by volume,and impregnation time of 24 h,respectively. the surface characteristics of the ac prepared under optimized conditions were examined by ph zpc,sem-edax,xrd,and ftir. competitive adsorption of ni 2+ ions on ricinus communis leaves by microwave assisted zinc chloride chemical activation (zlrc) present in binary and ternary mixture was compared with the single metal solution. the effects of the presence of one metal ion on the adsorption of the other metal ion were investigated. the experimental results indicated that the uptake capacity of one metal ion was reduced by the presence of the other metal ion. the extent of adsorption capacity of the binary and ternary metal ions tested on zlrc was low (4869) as compared to single metal ions. comparisons with the biosorption of ni 2+ ions by the biomass of zlrc in the binary (48.9868.41-ni-cu and 69.7666.29-ni-cr) and ternary solution (67.3257.07-nicu and cr) could lead to the conclusion that biosorption of ni 2+ ions was reduced by the influence of cu 2+ and cr 3+ ions. the equilibrium data of the adsorption was well fitted to the langmuir isotherm. the adsorption process follows the pseudo-second-order kinetic model. © 2013 m. makeswari and t. santhi.