Bleaching of pearl millet <scp> <i>(Pennisetum glaucum)</i> </scp> fibres with ozone

Abstract This study investigates the bleaching of pearl millet straw fibres, comparing conventional hydrogen peroxide wet processing with an alternative dry ozone treatment. The inherent golden yellow colour of these novel fibres necessitates bleaching before dyeing applications. The research examined critical ozone treatment parameters, including pH, moisture content, exposure time and power settings to optimise whiteness outcomes. Both bleaching methods achieved comparable levels of whiteness and fibre strength retention. Comprehensive characterisation of fibres through SEM–EDX, XRD and FTIR techniques revealed substantial structural modifications after bleaching treatment. Bleaching increased fibre crystallinity from 60.5% to approximately 65.2%. FTIR analysis demonstrated pronounced lignin reduction in ozone‐treated samples, while SEM analysis revealed distinct morphological changes including fibril separation and micropore formation. These structural modifications enhanced the water absorption properties of ozone‐bleached fibres. The findings establish dry ozone bleaching as an effective and environmentally sustainable alternative to conventional peroxide treatment, achieving comparable technical performance while eliminating chemical usage and water consumption. This development presents significant implications for eco‐friendly bleaching of natural fibres at industrial scale.