Integrating agro-ceramic waste in clay-based porous ceramics for eco-friendly cooling applications

Rising global temperatures emphasize the need for sustainable cooling solutions, especially in regions with limited access to conventional energy. This study develops clay-based porous ceramics incorporating rice husk (RHP) and ceramic waste (CWP) to optimize properties for evaporative cooling. Raw materials were characterized (XRD, ICP-AES, DTA/TGA, particle size), and samples with varied RHP/CWP ratios were shaped and fired (900–1100°C) to assess hydrophilic and mechanical properties. Increasing RHP content enhanced porosity and water uptake but reduced strength, while higher firing temperatures and CWP promoted densification. The optimal composition (85% clay, 15% RHP), fired at 900°C achieved ~36.8% porosity, capillary absorption > 18 g·min⁻¹·m⁻², permeability > 0.004 mm/s, and flexural strength > 2 MPa. Prototype testing confirmed up to 11.6 °C temperature reduction and 0.82 wet-bulb effectiveness. These results demonstrate the potential of agricultural and ceramic waste valorization for producing low-cost, high-performance porous ceramics suitable for evaporative cooling applications.