Toxic heavy metal ion adsorption kinetics of Mg(OH)(2) nanostructures with superb efficacies

Presence of both Cd(II) and Pb(II) ions in water is highly toxic for human health. That is why WHO recommends maximum permissible values of cadmium and lead in drinking water as 0.003 mg.L-1 and 0.01 mg.L-1, respectively. Therefore, here we report for the first time the adsorption kinetics of Mg(OH)(2) for adsorptions of Pb(II) and Cd(II). To the best of our knowledge, this is the very first attempt to evaluate the Langmuir and Freundlich isotherms of Mg(OH)(2) nanostructures with different morphologies for adsorptions of Pb(II) and Cd(II). The changes in adsorption processes with temperature are also studied. The Mg(OH)(2) nanostructures reduce the concentration of Cd(II) ions from as high as 1000 mg.L-1 to as low as 0.001 mg.L-1 and that of Pb(II) ions from as high as 1000 mg.L-1 to as low as 0.009 mg.L-1 . These values are much lower than the permissible limits prescribed by WHO. To attain these very significant achievements the time dependent changes in pore size, pore size distribution and surface area are explored. Finally, the results obtained by XRD, FTIR, Raman, pore size, pore size distribution, BET surface area, FESEM, TEM, EDX and adsoption kinetics studies show that nanoplatelet Mg(OH)(2) powders exhibit the highest respective adsorption efficacies of 3700 mg.g(-1) and 3030 mg.g(-1) for Pb(II) and Cd(II). Thus, the nanoplatelet Mg(OH)(2) powders may possibly find huge usage in near future for water purification applications.