Optimisation of flax rove bleaching using Box-Behnken design of experiments

Abstract

This study aims to optimise the flax rove bleaching process using Box Behnken design in combination with response surface methodology. The effects of hydrogen peroxide concentration, sodium hydroxide concentration, bleaching time, and temperature on whiteness index and weight loss are evaluated for their individual and interaction effects. Statistical analysis reveals that all process variables significantly affect the whiteness index, while sodium hydroxide concentration and temperature predominantly influence weight loss. Multi-response optimisation using a desirability function identified the optimum conditions as 0.09 kg/kg H₂O₂, 0.02 kg/kg NaOH, 60 min, and 91.3 °C, achieving a whiteness index of 70.4 and weight loss of 8.88%. The findings demonstrate the potential for attaining high whiteness with minimal fibre damage under optimised bleaching parameters.