Keywords: ionic exchange, LECA zeolite, heavy metals, plug flow reactor, breakthrough curves, lead removal, copper removal, cobalt removal, nickel removal, environmental pollution, water pollution
Lead, copper, cobalt and nickel removal from water solutions by dynamic ionic exchange in LECA zeolite beds
LECA zeolite, a novel material containing zeolite crystallised on light expanded clay aggregates (LECA) substrates with the aid of a hydrothermal process, was used in ionic exchange applications. LECA zeolite combines the porosity, low density and good mechanical properties of LECA substrates with the microporosity and ion-exchange properties of zeolites. In the present work, the dynamic ionic exchange of heavy metals was studied in a bed reactor filled with well-characterised LECA zeolite. Measurements were carried out of the parameters that describe the performance of the plug flow ionic exchange bed reactors (PFIEBR) during dynamic ionic exchange in LECA zeolite columns, removing Pb2+, Cu2+, Co2+ and Ni2+ from water solutions. The results indicated that Pb2+ is particularly selectively exchanged in comparison with Cu2+, Co2+ and Ni2. The selectivity decreased in the following order Pb2+ > Cu2+ > Co2+ ≅ Ni2+. The results indicated that LECA zeolite could be effectively used in heavy metal removal from wastewater.