Floating Sponge Could Help Remove HABs

 Seagriculture EU 2024
Floating Sponge Could Help Remove HABs

Researchers coated a floating sponge in charcoal-like powder that, when paired with an oxidizing agent, destroyed over 85% of HAB cells.

C​urrent methods to remove or kill toxin-producing algae and cyanobacteria aren’t efficient or practical for direct applications in waterways. Recently researchers reporting in ACS ES&T Water coated a floating sponge in a charcoal-like powder and, when paired with an oxidizing agent, the technique destroyed over 85% of algal cells from lake and river water samples.

Swaths of electric green and bright orange-red HABs, or the less brilliantly colored cyanobacteria Microcystis aeruginosa, can produce toxins that can sicken humans and animals. Researchers have shown that acids and strong oxidizing agents damage and destroy M. aeruginosa cells but simultaneously generate unwanted, potentially harmful products.

Destruction without damaging the environment

More recently, Jiangfang Yu, Lin Tang, and colleagues suggested that persulfate-based oxidants could control this species’ algal blooms, but these compounds require catalysts, such as powdered biochar — a charcoal-like substance made from carbon-containing waste — to be effective. So, the team set out to develop a floating material containing biochar that would boost the destruction of harmful algal cells without damaging the environment with byproducts.

The researchers started with a porous sponge made of melamine and developed a powdered biochar from shrimp shells. They sandwiched a thin layer of polyvinyl alcohol between the sponge and the biochar, linking the layers together at 572 degrees Fahrenheit. In combination with a persulfate-based oxidizing agent, the floating sponge damaged the membranes of about 90% of the M. aeruginosa cells in lab dishes within five hours.

After the membranes split apart, the cells released their internal contents, which rapidly broke down into smaller components. In addition, the researchers applied the catalyst sponge and persulfate system to real-world lake and water samples and found that it inactivated more than 85% of the algal cells. Based on the results, the team suggests that the new system could be a successful algal remediation technique in environments affected by blooms.

The authors acknowledge funding from the National Natural Science Foundation of China, the China Postdoctoral Science Foundation, the National Key Research and Development Program of China, the Hunan Natural Science Foundation of Hunan Province, and the Changsha Municipal Natural Science Foundation.

Seagriculture USA 2024
AlgaeMetrics

Subscribe

Breaking-News

  • April 22, 2024: New England Kelp Harvest Week, a project started by the Sugar Kelp Collective in 2021, runs from April 20-30 this year. The group of kelp farmers and activists works with restaurants, bakeries, and fish markets to create special dishes and menus that use the sea vegetable, which grows in winter and is harvested in the spring. Across Connecticut, this provides an ideal opportunity for people to explore dishes and cocktails made with kelp. READ MORE...
  • April 19, 2024: Hospitalized COVID-19 patients who took spirulina had a lower risk of death than those who did not, according to results of a randomized controlled trial recently published in Frontiers in Immunology. READ MORE...
  • April 17, 2024: A research team exploring the untapped potential of seaweed farming for carbon sequestration is positioning Taiwan to play a role in offsetting global carbon emissions. READ MORE...
  • April 15, 2024: Somater, a French manufacturer of plastic and polymer primary packaging for cosmetics, pharmaceuticals, food, and industry, has partnered with French start-up Eranova to create a 100% bio-based line of packaging from green algae collected on the banks of a brackish water lagoon near Marseille, in the south of France. READ MORE...

Algae Europe 2024

A Beginner’s Guide