How Discarded LCD Panels can Solve the Wastewater Treatment Challenge?

The dual challenge of mounting electronic waste and rising industrial pollution requires innovative, sustainable solutions. Textile industries, a key part of India’s economic landscape, generate wastewater laden with persistent dyes, such as methylene blue, which are difficult to remove, contribute significantly to water pollution, and require advanced treatment methods. Simultaneously, discarded electronic devices continue to add to an ever-growing e-waste burden. Addressing these interconnected challenges requires rethinking how resources are used and reused.

In response to this challenge, the research led by Professor Ramya Srinivasan, along with students Anjali Dubey and Shyam Thakrar from the School of Engineering and Applied Science, proposes a solution that brings together environmental sustainability, cost efficiency, and technological innovation. It adopts a circular economy approach by repurposing discarded Liquid Crystal Display (LCD) panels as anodes, paired with Reticulated Vitreous Carbon (RVC) cathodes, to serve as electrodes in an electro-peroxone wastewater treatment process. By transforming obsolete LCD screens into active electrodes, the research not only reduces e-waste but also enhances pollutant degradation, enabling the treatment of real textile effluent.

Several electrochemical advanced oxidation systems use platinum-based electrodes. However, these electrodes are highly expensive, entail significant environmental costs due to resource-intensive extraction and processing, and are subject to supply constraints because production is geographically concentrated. The approach's ability to achieve near-parity with conventional platinum-based systems without the associated economic and environmental costs makes it unique. It exemplifies how waste materials can be re-engineered into valuable resources, addressing both environmental pollution and economic constraints in wastewater treatment technologies.

The system operates through the electro-peroxone process, using repurposed LCD electrodes. Hydrogen peroxide generated at the cathode reacts with externally added ozone to produce hydroxyl radicals (•OH), which are highly reactive oxidants capable of non-selectively degrading complex dye molecules. The system’s performance is further evaluated against conventional platinum-coated titanium electrodes, using different electrolytes such as sodium sulphate, sodium chloride, and potassium sulphate to assess efficiency under varying conditions.

The results revealed that this alternative system closely matches the conventional platinum-based setups. The LCD–RVC system achieved up to 99.46 per cent removal of methylene blue within just 20 minutes, compared to 99.99 per cent achieved by the platinum-based system, indicating only a marginal difference in performance. Among the electrolytes tested, potassium sulphate (K₂SO₄) delivered the best results, while sodium chloride and sodium sulphate showed slightly lower but still strong efficiencies of around 97 per cent and 96 per cent, respectively.

Beyond the laboratory, the research offers a promising alternative to addressing real-world challenges. The system’s effectiveness extends beyond controlled laboratory conditions, exhibiting strong performance in real textile wastewater treatment, with significant reductions in COD (75 per cent), turbidity (80 per cent), total suspended solids (57 per cent), and total organic carbon (30 per cent).

The work exemplifies how scientific inquiry, fuelled by experimentation and critical thinking, can lead to effective and accessible solutions. This is where Ahmedabad University’s philosophy becomes evident. The University’s emphasis on research thinking as a core pedagogical pillar encourages faculty and students to engage deeply with complex problems, question existing systems, and explore interdisciplinary solutions.

The study, “Degradation of methylene blue using inutile LCD panels as novel anodes: A potential replacement for platinum-based electrodes,” published in the Journal of Environmental Management, presents a strong case for rethinking waste as a valuable resource in environmental engineering. By developing a cost-effective electrode system from discarded LCD panels and rigorously validating its performance against conventional platinum-based technologies, the research shows that sustainable alternatives can deliver near-equivalent efficiency without the associated economic and ecological burden. More than a technical advancement, the study pushes the boundaries of knowledge and innovation, offering practical pathways toward cleaner technologies, sustainable industrial practices, and more responsible use of resources in society.