Bleach catalysts: more sustainable compact laundry bleaching systems and the impact on fabrics

Oxidative bleaches are one of the main technology classes that deliver strong cleaning performance in powder laundry detergents. They also make up a large proportion of a typical powder detergent, delivered in the form of percarbonate and tetraacetylethylenediamine (TAED). As the laundry detergent industry transitions to Net Zero carbon footprint formulations, in line with the urgent need to maintain global warming within 1.5 degrees C, formulation strategies will shift to a reduction in the total chemistry per dose, relying more on catalytic chemistry. In the case of bleach, this will mean more focus on metal oxidation catalysts. These technologies deliver efficient cleaning in a mass-efficient fashion but can have a negative impact on fabrics. The aim of this PhD will be to deepen our understanding of catalyst impact on fabrics, providing comprehensive evaluation of the factors leading to any negative impacts (dye interactions, impact of soil, water quality, wash temperature, laundry additive usage (oxygen- or chlorine-based bleaches)). The research will take into account the change in fabric and dye landscape since metal catalysts were previously considered for use in laundry detergents in the mid-1990s.