Researchers have found an eco-friendly approach that can eliminate the use of toxic chemicals in silk processing.
Traditionally, toxic chemicals like sodium carbonate, sodium hydroxide, sulfuric acid, and lithium bromide have been used to extract silk proteins, fibroin and sericin from various types of raw silk fibres, an important step in the process of making silk from cocoons.
A team at the Institute of Advanced Study in Science and Technology (IASST) Guwahati has identified Ionic Liquids (ILs) which can be promising sustainable alternatives to the toxic chemicals currently in use for the silk protein extraction process, according to a press release from the Department of Science and Technology, Government of India.
The team, led by Dr Kamatchi Sankaranarayan, has identified 4 different ILs that can be effective in extracting silk proteins from raw fibres.
This new research, published in Chemistry Select by Wiley Publishers, has potential for use in sericin extraction from both mulberry (Bombyx mori) and non-mulberry silks, such as Muga (Antheraea assamensis) and Eri (Philosamia ricini), indigenous to Northeast India.
The researchers explored six different ILs and found some of them were particularly effective in removing sericin without damaging the silk protein structure. The ones showing the greatest promise included 1-Butyl-3-methylimidazolium chloride (BMIM.Cl), 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIM.BF4), and Tetraethylammonium bromide (TEAB). TEAB appeared to be highly effective due to its ability to destabilize sericin proteins.
The research holds great significance for the silk industry. Not only does it offer a more environmentally friendly alternative to traditional chemical methods, but it also paves the way for efficient sericin extraction from non-mulberry silks, potentially leading to new applications for these unique fibres. This is the first instance of using ILs for sericin extraction from non-mulberry silks, highlighting the potential of this new approach for a more sustainable and diverse silk industry.
