Phycoremediation of heavy metals

Paper in proceeding, 2016

Increasing amounts of heavy metals is a growing societal problem. By using ion exchangers, heavy metals can be captured and thereby their environmental impact can be decreased. Microalgae have been shown to adsorb metals; the algal cell wall contains functional groups, such as amino-, carboxyl-, hydroxyl- and sulphate groups, to which the various metal ions could bind [1]. This makes them suitable as a sustainable alternative for environmental remediation. Removal of pollutants with algae is called phycoremediation and is well studied for e.g. waste water [2]. Within this project, we study the potential of microalgae for remediating heavy metals in low concentration originating from leaching of combustion ashes, by measuring the metal binding capacity by three phytoplankton species: Chlorella sauna, Dunaliella sauna and Scendesmus obliquus. The heavy metals assessed are divalent ions of copper (Cu), cadmium (Cd), zinc (Zn), mercury (Hg) and lead (Pb). The effect of pH has been determined, as well as binding over time.