Coupling Ion Exchange and Biosorption for Copper(II) Removal From Wastewaters

A coupled process of ion exchange and biosorption for recovery of copper(II) from wastewater has been proposed. In this process a cation exchanger has been used as a carrier for the biofilm formation. Two different types of microorganisms capable for copper biosorption have been selected for immobilization, i.e, effective microorganisms and activated sludge microorganisms. As a regenerating agent solutions of sodium bicarbonate with aqueous ammonia as an additive have been used, which allowed operating the column under mild pH conditions. The activity of biofilm was preserved after the cyclic process of ion exchange and regeneration. The effect of biofilm on the mass transfer kinetics and the ion exchange equilibrium was quantified by comparing the efficiency of ion exchange on the fresh bed and that covered by biofilm. The linear driving force model was used for simulations of the process dynamics.