Scientists Develop Nanomaterial from Seaweed to Treat Toxic Wastewater without Chemicals


Treating toxic wastewater produced by industries often involves use of chemicals to release the treated water into sanitary sewers or surface water in the environment. But, because of the use of chemicals in treating this water, they had a negatively impact on the plant and animal life.

As an answer to this, scientists have developed a new nanomaterial that is obtained from a seaweed which has a very high capacity of absorbing chemicals like lead and chromium.

This seems to be a very efficient and environmental-friendly technique to treat wastewater without the use of any chemicals. The team of Indian scientists focused on carbon-based cleaning process as opposed to the membrane based filtration process that cannot filter out heavy metals that contaminate the water.

Together with the processes that use carbon nano tubes, graphene and activated carbon to deal with this problem, these scientists have developed a cleaning process that is carbon based by using a green seaweed as the foremost cleaning material.

In this process, the seaweed Ulva fasciata is used to synthesize a nanocomposite of grapheme-iron sulphide through direct pyrolysis technique. Earlier, the seaweed was also used to absorb zinc and copper ions from contaminated water but the process was not so effective. Scientists have now solved this problem by making thin carbon sheets from the seaweed by subjecting it to high temperatures.

The better part is that these sheets of nanocomposites can be used for as much as eight cleaning cycles as they have much higher adsorption capacity and the sheets can also effectively absorb effective dyes including cationic and anionic dyes. The team claims that this is the highest capacity for any carbon material derived from biomass.

The team, led by Dr. Ramavatar Meena, claimed that the new nanomaterial could effectively remove even highly toxic compounds like hexavalent chromium from wastewater. The study was published in the Journal of Hazardous Materials.

Mr. Meena further added that the nanocomposite was more suitable for the pre-treatment of wastewater that is highly contaminated as the seaweed did not have any negative effect on its adsorption capacity even when treated with the presence of high concentration of salts.

Tests involving the nanocomposite after it was deposited on a filtration paper and then using it in a continuous filtration mode resulted in rendering the black dye solution which is considered highly toxic into colourless water. This means that the configuration can also be used in effective treatment of wastewater treatment for the textile and dye industry.