A research team of Indian Institute of Technology (IIT) Mandi has developed a fibrous membrane filter using a biopolymer-based material to remove heavy metals from water.
Results of the research have been published in the journal Polymer. The paper has been co-authored by Dr Sinha Ray and his research scholar, Mr Ashish Kakoria, along with Dr Suman Sinha Ray, Adjunct Assistant Professor, University of Illinois at Chicago.
Heavy metals in water could lead to several neurological problems in humans including Alzheimer's disease, Parkinson’s disease, and multiple sclerosis.
These adsorbents contain a large amount of a biopolymer, Chitosan, derived from crab shells that is mixed with a well-known polymer, Nylon.
The researchers found that while normally adsorbent fibres bind to the target metal only at their surface, in their nanofiber membranes, the adsorption was seen to happen at the sub-surface scale as well, which translates to higher metal removal efficiency as per the researchers’ hypothesis.
Solution blowing is an innovative process for spinning micro-/nano-fibers from polymer solutions using high-velocity gas flow as fiber forming driving force.
Solution blowing produces fibres that are nanometres in diameter, a hundred thousand times thinner than a single human hair. Finer than those produced through the process of Melt Blowing. This increases the surface area of fibers tremendously, resulting in better adsorption of heavy metals.
This method also enables blending of higher concentration of natural polymers like chitosan and lignin with synthetic polymers like Nylon.
Heavy Metals are micronutrients which the human body requires in trace amounts. These metals resemble each other and apart from their physiological significance, they also have medical effects, which are both positive as well as negative. Each metal exhibits a number of different effects on the health of the human body. The heavy metals are a diverse group of chemical elements and have no common structural feature or properties.
The heavy metals found in drinking water such as lead, mercury, arsenic, and cadmium have no beneficial effects on our body. Human exposure to heavy metals has been associated with many health problems, from asthma to kidney disease. Consequently, it is an important public health issue to control the sources of contamination and reduce human exposure.