Removal behavior of sericite for Cu(II) and Pb(II) from aqueous solutions: Batch and column studies

Applicability of naturally and abundantly available sericite was assessed for the removal of two important heavy metal toxic ions viz., Cu(II) and Pb(II) from aqueous solutions. The present investigation is an attempt for cleaner/greener cost effective technologies in waste/effluent water treatment. The batch type experiments showed, sericite was found to be useful sorbent for the removal of these two cations from aqueous solutions. It is to be observed that with the increase in sorptive concentration, the amount of metal uptake increased and the concentration dependence data were fitted well for the Langmuir adsorption isotherm than Freundlich adsorption model. Langmuir monolayer adsorption capacity was found to be 1.674 mg g−1 for Cu(II) and 4.697 mg g−1 for Pb(II). Kinetic studies enabled, a rapid equilibria was established between the soild/solution interface as within ca. 10 min for Cu(II) and ca. 90 min for Pb(II). Moreover, the removal behavior of sericite for these two metal ions was greatly influenced by the solution pH. Further, the column data were explained with the Thomas model hence to optimize the Thomas constants for these two ions, i.e., Cu(II) and Pb(II) for sericite.