Mussels, shellfish or naiads can now be used to rid industrial waste water of polluting dyes! Researchers at UAE’s Khalifa University have developed a new nano material made from a polymer called polydopamine and modified with an ionic liquid which creates a new adsorbent material for removal of anionic pollutants from water.
- Anionic pollutants carry a negative charge and are often found in industrial wastewaters from a variety of sources, including metal plating, mining, and textile dyeing.
- The scientists first tested their mussel-inspired solvent on a red-orange dye called Alizarin Red S. The report says that it is effective at cleaning up the dye without leaking any harmful chemicals into the surrounding water.
THE RESEARCH TEAM: The team, led by Professor of Chemical Engineering and Director of the Research and Innovation Center in Graphene and 2D Materials (RIC-2D) Hassan Arafat, Research Associate Rawan Abu Alwan, Research Assistant Botagoz Zhuman, Research Scientist, Dr Mahendra Kumar, and Professor of Chemical Engineering, Prof Enas Nashef, published their work in Chemical Engineering Journal.
HOW MUSSELS CLEAN: Mussels are marine animals that attach themselves to a variety of surfaces using byssus threads, which are made from a protein containing dopamine.
- In humans and mammals, dopamine is a neurotransmitter that plays a role in reward-motivated behaviour, but in mussels, it acts as a natural adhesive.
- Polydopamine is a synthetic polymer that mimics the structure of this dopamine-containing protein. It has the ability to coat a variety of surfaces and provides a versatile platform for surface modifications.
- The polydopamine was modified with an ionic liquid to create a new adsorbent material.
- Ionic liquids have been gaining attention in recent years as potential alternatives to traditional solvents due to their low volatility, thermal stability, and ability to dissolve a wide range of compounds.
- They are also considered eco-friendly and sustainable thanks to their low volatility and ability to be recycled. The ionic liquid in this project was chosen based on its ability to form hydrogen bonds with the anionic pollutants, enhancing their affinity for the modified polydopamine.
- Modifying the polydopamine with the ionic liquid allows for the creation of a material with enhanced adsorption properties for anionic pollutants: The polydopamine provides a versatile platform for surface modifications, while the ionic liquid provides the selectivity and affinity for the pollutants.
- The team’s material is also reusable.
- Methanol was used to wash the material and desorb the dyes used in experimental testing. The team put the material through four cycles of adsorption-desorption without any significant performance deterioration or loss of structural integrity, proving its potential as an adsorbent material for use in industrial wastewater treatment applications.
WHAT THEY SAID:
Surface and groundwater pollution caused by industrial dye-loaded wastewater effluents threatens human health and ecological systems, causing a serious environmental problem in many countries. Several treatment techniques have been applied to remove dyes from wastewater, and among these, adsorption is considered the most economically feasible and easily applied. However, traditional adsorbents offer low selectivity and the process can produce secondary waste products.
— Hassan Arafat (team lead)
Professor of Chemical Engineering
Khalifa University
