Seafood Waste-Based 'Sponge' Could Help Clear the Sea
A new material arose from a chemistry lab in Canada that has surprising properties: A new form of calcite that can absorb water as well as oil and dyes.
Scientists from the Memorial University of Newfoundland in St John’s discovered this new sponge-like calcium carbonate after treating discarded mussel shells with dilute acetic acid. The team was looking to create a de-icer for treating roads in winter, and instead came across this new material.
Their findings were published in the Cell Press journal Matter on November 5.
The incredible material can absorb up to 10 times its own mass in liquids, which means it can also absorb contaminants such as oil and dyes.
It's an exciting new prospect for marine clean-up projects, however, the material can't yet be made en-masse. So the team has suggested it may be useful in drug delivery or for biomedical uses.
The team came upon the new material by grinding up disused blue mussel shells into dilute acetic acid. After leaving them overnight, the scientists noticed it had turned into spongey white pads when they were wet, and turned into some sort of cotton-ball when dry.
"I knew the water-soaked material had to be calcium carbonate – based on what I had put in the flask, there was nothing else chemically it could have been. However, I had no idea why it was forming with a sponge-like texture," said Dr. Jennifer Murphy, who worked on the project at Memorial University and who first discovered the material.
By using X-ray diffraction and scanning electron microscopy, the team discovered the material was made up of a nest-like "formation of calcite crystals," as Chemistry World explained.
"It’s difficult to replicate inorganic materials the same way as many organisms, like mussels do," said Dr. Murphy.
"That is how we realized the prisms were coming free of the shell and recombining to make the soft calcite material."