Sunlight a Solution For Dye Waste

The scientists have developed a photocatalyst using titanium dioxide doped with red seaweed polymer carrageenan to degrade the dyes. The Central Salt & Marine Chemicals Research Institute Bhavanagar, Gujarat have been able to totally degrade three industrial dyes- methyl orange, methylene blue, and reactive black 5 in the presence of sunlight.

According to the study, more than 500 tonnes of non-degradable textile color wastes are being disposed of in natural water bodies without sufficient treatment. Regardless of strict environmental regulations, a broad technique of treating industrial dyes is not available. The existing methods are expensive and do not completely break down the dye molecules to non-toxic constituents but simply concentrate the contaminants.

The nano composite is an outstanding photocatalyst that helps in degrading the industrial dyes quickly in a single-step procedure. The photocatalyst prepared in the lab was found to degrade the dyes when exposed to direct sunlight between noon and 2 pm during May-July.

Researchers when used the solar concentrator the degradation process was quick. It took only five minutes for reactive black-5 and mathylene blue to degrade and methyl orange degraded completely in 20 minutes.

The study also states that the nanocomposites are thermally stable and are reusable up to six times with its effectiveness at over 97%. These photocatalyst are completely safe and can treat dangerous dyes in an eco-friendly and cost-effective manner