NEW DELHI — Researchers at the National Institute of Technology Rourkela on Thursday announced an innovative process for efficiently treating industrial wastewater contaminated with persistent dyes that can cause cancer.
The research, supported by Anusandhan National Research Foundation, showed that combining nanocomposite-based ceramic membranes with microbubble technology can help enhance dye removal efficiency.
Wastewater from industries like textiles and dye manufacturing often contains harmful dyes that are difficult to remove with traditional filtration methods. Dyes such as Bismarck Brown R are small enough to pass through microfiltration membranes, making them particularly challenging to treat. These dyes can cause significant environmental and health issues due to their intense colour and potential carcinogenic properties.
Conventional treatment methods, such as those relying on Ultraviolet (UV) light, often struggle with large-scale applications, especially when separating dye particles from water. To address these challenges, the team developed a cutting-edge treatment system that combines two advanced technologies.
The first is a ceramic membrane coated with an industrial-waste-derived Zeolite and Zinc Oxide nanocomposite. This photocatalyst can break down dye molecules when exposed to light.
The second technology incorporates microbubbles, generated via a simple air diffuser, to enhance mass transfer and improve the breakdown process.
A continuous tangential flow membrane photoreactor was designed and tested using both simulated and real wastewater from a local dyeing factory.
"Our hybrid system successfully achieved 95.4 per cent decolourisation of Bismarck Brown R and 94 per cent removal of chemical oxygen demand (COD) in just 90 minutes," said Prof. Sujit Sen, Department of Chemical Engineering at NIT.
“The nanocomposite performed well under visible light, making this approach suitable for practical wastewater treatment applications,” he added.
The potential applications of this hybrid system are vast. It offers a more efficient and cost-effective alternative to conventional oxidation methods, which often rely on expensive chemicals and complex equipment.
The technology could also be applied across industries such as textile manufacturing, and chemical industries such as steel, petrochemicals, and pharmaceuticals, where robust wastewater treatment is required.
The research has been published in the Journal of Environmental Chemical Engineering.