Article courtesy of Tereza Pultarova| July 23, 2015 | Engineering and Technology Magizine | Shared as educational material
A synthetic device in the shape of corals could be used to remove toxic heavy metals from the world’s oceans, a study suggests.
The device, described in the latest issue of the Journal of Colloid and Interface Science, is made of aluminium oxide nanoplates.
The material has been previously tested as a possible pollutant removing agent but with limited results.
Engineers at China’s Anhui Jianzhu University concluded the performance of the material could be improved by changing the shape and structure of the device made of the material.
They drew inspiration from nature and curled the aluminium oxide nanoplates into a coral-like structure. The decision to use the coral shape was prompted by the known ability of the marine invertebrates to absorb and accumulate heavy metals such as mercury, lead or arsenic that escape into the environment from industrial facilities.
For real corals, however, the exceptional ability to absorb heavy metals is frequently fatal.
“Adsorption is an easy way to remove pollutants from water, so developing new products that can do this is a big challenge in environmental remediation,” said Xianbiao Wang, from Anhui Jianzhu University in China. “The chemical and physical structure of such products is very important; it is interesting to design and fabricate adsorbents with different structures to see how they behave. In particular, materials that mimic biological adsorbents like coral have potentially huge applications.”
The researchers tested the coral-like nanoplates in water contaminated with mercury. They found that the coral-like structure removed around 2.5 times more mercury from the water than the traditional aluminium oxide nanoparticles.
“We are very excited about the results, which provide a good example for the production of coral-like adsorbents,” said Wang. “We hope our work provides inspiration for more research into the development of materials that mimic biological organisms.”
Heavy metal contamination of the world’s oceans is a huge problem for the security of the global food chain. Marine fauna and flora accumulate the heavy metals. Especially larger types of fish, popular among human consumers, have been shown to contain substantial levels of the toxic contaminants. As a result, people who consume such fish risk negative health effects related to the toxicity.
According to the WHO, between 1.5 and 17 in every thousand children living in selected subsistence fishing populations showed cognitive impacts caused by the consumption of fish containing mercury.