Graphene-Based Material for Desalination Developed
Context:
Recently, a new hydrophobic graphene-based material capable of efficient water desalination was developed by the Indian scientists to address the global freshwater crisis.
Relevance:
GS-03 (Science and technology)
Key Highlights:
The Freshwater Challenge:
- Despite 71% of Earth’s surface being water, only 3% is freshwater.
- Out of this, only 0.06% is easily accessible, with the rest locked in glaciers, polar caps, and deep underground sources.
About the Innovation:
- The graphene-based hydrophobic material enables advanced desalination by filtering salts more effectively.
- It has the potential to enhance access to clean drinking water globally, especially in water-stressed regions.
Desalination Technologies in Use:
- Thermal Desalination:
- Involves heating saline water and collecting condensed vapor.
- Examples: Multi-Stage Flash Distillation (MSF), Multi-Effect Distillation (MED).
- Used for seawater; energy-intensive and prone to corrosion.
- Example: LTTD plants in Lakshadweep.
- Membrane Desalination:
- Uses semi-permeable membranes to remove salts.
- Types: Reverse Osmosis (RO), Electrodialysis (ED/EDR).
- More space-efficient and eco-friendly (in ED), but fouling and waste disposal remain challenges.
- Example: Nemmeli RO Plant, Tamil Nadu (South India’s largest plant).
Prelims Question:
Q. Which of the following technologies is used in membrane-based water desalination?
A. Multi-Stage Flash Distillation
B. Multi-Effect Distillation
C. Vapor Compression Distillation
D. Reverse Osmosis
Answer: D
