IISER new material removes pollutants from water

Subject :Environment

Context:

Researchers at the Indian Institute of Science Education and Research (IISER), Pune came up with a custom-designed unique molecular sponge-like material — macro/microporous ionic organic framework — which can swiftly clean polluted water by soaking up sinister contaminants.

Water contaminants:

Systematic studies have identified various organic (organic dyes, antibiotics, pesticides, etc.) as well as inorganic toxic pollutants such as iodides, and oxo-pollutants like perrhenate that are carcinogenic in freshwater sources and can pose a direct threat to humanity and living organisms.

New material to purify water:

In general, commonly utilised sorbent materials often trap the pollutants through an ion-exchange strategy to purify water but suffer from poor kinetics and specificity.
To mitigate this issue, researchers have prepared a newly engineered material called viologen-unit grafted organic-framework (iVOFm).
The material employs amalgamation of electrostatics driven ion-exchange combined with nanometer-sized macropores and specific binding sites for the targeted pollutants.
The size and number of tunable macropores along with the strong electrostatic interaction of iVOFm can quickly remove various toxic pollutants from water.
Researchers employed a make-and-break strategy to grow a charged porous organic polymer (POP) as a sponge-like infinite framework on silica nanoparticles that is used as a template.
Following this, the silica nanoparticles were strategically removed to create ordered hierarchical interconnected macro/microporosity throughout the material.

Fast diffusion:

This material features inherent cationic nature and macroporosity to allow fast diffusion of pollutants.
When tested for a wide array of water pollutants, it showed ultrafast capture of all the pollutants– both organic and inorganic- with over 93% removal in just 30 seconds.
The engineered material could remove sulfadimethoxine antibiotic with high efficiency.
It can also be used several times to clean contaminated water.