Up cycling prickly pear peel waste for sustainable wool dyeing using microwave irradiation

This study explores the valorization of prickly pear (Opuntia ficus-indica) peel waste as a sustainable natural dye for wool fabrics. Dyeing was conducted using both conventional mordant-assisted (4% tannic acid) and mordant-free microwave-assisted methods. Key parameters including dyeing time and pH were optimized to enhance color strength. Microwave-assisted dyeing substantially reduced processing time and energy consumption compared to the conventional method. The dyed fabrics were evaluated for mechanical properties, color strength, fastness properties, ultraviolet protection factor (UPF), and antibacterial activity. Microwave-dyed samples exhibited higher color strength, improved fastness ratings, higher UPF values, and better antibacterial activity than conventionally dyed samples. In addition, the microwave process produced effluent with lower BOD, COD, and TDS levels. These findings indicate that prickly pear peel extract combined with microwave technology offers a promising eco-friendly approach for producing colored wool fabrics with added functional properties while reducing environmental impact.