Absorption of sodium humate on cotton fabric

Sodium humate was applied to the dyeing of cotton fabrics.The effects of pH value,temperature,dosages of sodium chloride and sodium humate,and bath ratio on △E value of the dyeings were investigated,along with the absorption dynamics and thermodynamics of sodium humate on cotton.It was found that pH values had less effect on △E value of the dyed fabrics;the △E value decreased with the increase of temperature and bath ratio.When the dosage of sodium chloride ranged from 0 to 15 g/L,the △E value increased with the increase of sodium chloride,but decreased with the increase of the bath ratio;sodium humate exhibited good building-up on cotton;higher the dyeing temperature,faster the absorption rate of sodium humate on cotton;and shorter the half-dyeing time t1/2,lower the equilibrium uptake C∞.Freundlich equation is fit to describe the absorption of sodium humate on cotton,its absorption on cotton is effected mainly by hydrogen bonding and Van der Waals forces.