removal by the combination of ultrasound and TiO/biochar.

Harmful cyanobacteria blooms are increasing. They call for novel removal technology, since the required doses of algaecides may cause further environmental pollution or damage treatment facilities. Undesirable intracellular compounds can be released in the water when cyanobacterial cells are damaged. For the first time, ultrasound irradiation was combined with TiO/biochar (TiO/BC) at relatively low dosage and tested as an alternative for promoting the coagulation of in water treatment. This pre-oxidation process removed 92% of cyanobacterial cells after coagulation. With the combination of ultrasound and TiO/BC treatment, the dissolved organic carbon and microcystins levels did not increase significantly. The oxidative treatments enhanced the permeability of the cyanobacterial cell membranes, which may be due to the various active species generated from the ultrasound and TiO/BC process. The results showed that the TiO/BC hybrid catalyst could be a potential candidate for cyanobacterial cells removal in water.