Current Affair 1:

News:

Groundwater is an essential source of drinking water across the country. However, heavy metal contamination in groundwater presents a significant health hazard.

Researchers at the Indian Institute of Science (IISc) have developed a nanomaterial-based solution that can effectively reduce the presence of heavy metals like chromium in groundwater.

How chromium enters system?

Chromium typically enters soil and groundwater through effluents from industries such as leather tanning, electroplating, and textile manufacturing. Heavy metals enter the environment because of urbanization and certain mismanagement by industries.

What is the current method?

Presently, most current methods for removing heavy metal contamination rely on pumping out water from the ground, followed by purification using chemical precipitation, adsorption, ion exchange, and reverse osmosis carried out at different locations.

What IISC did do?

The IISc team instead proposes an on-site alternative that involves using iron nanoparticles that can remediate the heavy metals.

1. They did the coating of carboxymethyl cellulose (CMC) over nano zero-valent iron (nZVI).
2. Then they boosted the reactivity of the CMC-nZVI by exposing it to sulphur-containing compounds in anoxic conditions.
3. This enabled the formation of a protective iron sulphide layer on the surface, a process called sulphidation.
4. These modifications improved the stability of the S-CMC-nZVI and maintained its reactivity and efficiency.

S-CMC-nZVI showed nearly 99% efficiency at Cr6+ removal under different conditions such as different pH levels and the presence of other competing ions that might be found in groundwater.

<< Previous Next >>