Experimental removal of Alexandrium tamarense cells using sulfobetaines and their modified clays

To find new chemical modifiers and new modified clays with excellent algae removal efficiency, the removal effects of betaine and five sulfobetaines including octyl sulfobetaine, caprylyl sulfobetaine, lauryl sulfobetaine, myristyl sulfobetaine, and palmityl sulfobetaine (SB3-16) against the harmful alga Alexandrium tamarense were observed. Betaine and the five sulfobetaines exhibited certain removal effects against A. tamarense with the highest removal efficiency by SB3-16. Hence, a series of modified clay, montmorillonite (MMT) intercalated by SB3-16 were prepared, and their removal efficiencies were evaluated. The organo-clay with 11 wt% of SB3-16 exhibited the highest removal efficiency against A. tamarense cells. Combining the environmentally benign nature of SB3-16 and the high efficiency of SB3-16 modified clay against A. tamarense , SB3-16 modified clay could be a favorable choice to control harmful algal blooms (HABs) of this species.