engleski

Metal Ion Exchange by Natural and Modified Zeolites

The lead and cadmium removal from waste waters by natural and pretreatment zeolites was examined by using a batch-type method. The results demonstrated that the natural zeolites contained a complement of exchangeable Na, K and Ca ions but exposing them to 2 M NaCl solution at 22 oC and 70 oC, respectively, converted them to a near homoionic state in Na-form. Lead and cadmium removal results using natural zeolites and treated zeolites showed that treatment improved both the exchange capacity and the removal efficiency. The influence of the temperature on ion-exchange process was examined. It was found that the metal uptake was increased with increasing the temperature during the ion-exchange process. Natural and Modified zeolites remove toxic metals from waste waters. Key words: natural zeolites, modified zeolites, ion exchange, removal lead, removal cadmium

natural zeolites; modified zeolites; ion exchange; lead removal; cadmium removal

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