A simple and rapid harvesting method for microalgae by in situ magnetic separation

► A simple and rapid magnetic separation method for microalgae harvesting has been developed by using Fe3O4 nanoparticles. ► The recovery efficiency of both Botryococcus braunii and Chlorella ellipsoidea reached above 98% within 1 min. ► This magnetic separation technology provides a great potential to save time and energy for improving algal harvesting.