Kinetic of nickel (II) removal from aqueous solution using different particle size of water - cooled blast furnace slag

The adsorption of nickel (II) from aqueous solution onto different particle sizes of water-cooled blast furnace slag (WCBFS) was investigated. Batch experiments were performed to study the effect of contact time, initial concentration of nickel ions, initial pH of the solution, and temperature. The data was fitted to Langmuir and Freundlich isotherm models. The results showed that the Langmuir model better fitted the data obtained for the large-sized particles, while that for the finer-sized particles followed the Freundlich model best. Overall, the process was considered a second-order reaction which involved some degree of intraparticle diffusion. The calculated energy of activation indicated that it was a chemisorption process for both fine- and coarse-sized particles. In conclusion, the finest WCBFS particle size (0.3 mm) showed a good potential as an adsorbent to remove this divalent metal ions from solution.