Neck Height Design for Separation of Copper (II) from Wastewater Using Foam Fractionation

Document Type : Technical Note


Faculty Member, Industrial Chemistry, Group Fars Science & Technology Park


In spite of different water resources available at many locations, adequate supplies of fresh water are rare for human demands due to various sources of pollution. Water pollutants can be classified as 1) suspended pollutants and, 2) dissolved pollutants. Dissolved pollutants consist of acids and heavy metallic ions. Foam fractionation method which is based on differences in surface activity is a new method whereby dissolved solids are adsorbed on the surface of liquid bubbles. Various purposes are served by the separation of metallic ions from water which include removal of metallic ions from water and extraction of precious metals from wastewater. In this method, water is mixed with a surfactant and fed continuously to a column. The supernatant foam thus formed starts to move along the column neck. Finally the foam breaks up into two fractions of heavy metal ions and pure water each leaving the column through separate outlets. In this study, neck height design and optimization is investigated to achieve the best copper ion removal efficiency. Based on our experiments, it was found that increasing neck height up to a certain height increased the enrichment ratio. Also increasing metal ion concentration for a given neck height improved recovery.


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