화학공학소재연구정보센터
Journal of Chemical Technology and Biotechnology, Vol.80, No.5, 553-564, 2005
Removal of zinc from dilute aqueous solutions by galvanochemical treatment
The possibility of zinc removal, a common toxic metal, from simulated liquid effluents by the application of a novel treatment method, termed galvanochemical, was investigated. The galvanochemical process is considered as a simple, economic, friendly to the environment, method, which does not create harmful end-products. Synthetic wastewaters were examined, these contained concentrations of zinc commonly found in real wastewaters from small-to-medium size industrial units, such as metal-plating or metal-treatment plants. These liquid wastes pose an important environmental problem, due to the content of heavy metals. The optimization of the main operating parameters was the objective of the study. The galvanic pair scrap ratioiron:coke was used for these investigations. It was found that the use of the galvanic pair mixture of 80 g dm(-3) (weight per solution volume ratio), agitated at 160 rpm for 5h, removed more than 90% of zinc from the initial solution, containing initially 50 mg dm(-3) of zinc. The scanning electron microscopy/energy disperse spectrometry (SENVEDS) analysis performed on the products showed that zinc was adsorbed onto the coke to a small extent and that the zinc removal was mainly based on the adsorption of zinc onto the surface of active iron oxides formed as a result of galvanochernical reactions. (c) 2005 Society of Chemical Industry