Abstract: Humic acid sodium were applied to dyeing of cotton fabrics. The effects of dyeing value of pH, temperature, dosage of sodium chloride, dyeing bath ratio and dosage of humic acid sodium on △E value of dyeings were analyzed. The absorption dynamics and thermodynamics performance of humic acid sodium on cotton were also investigated. It was found that dyeing pH have less effect on △E value of dyed fabrics, the △E value of dyeings was decreased with the increase in dyeing temperature and dyeing bath ratio. When the dosage of sodium chloride from 0 to 15g/L, the △E value of dyeings was increased with the increase in dosage of sodium chloride, but when the dosage of sodium chloride above 15g/L, the △E value of dyeings was decreased with the increase in dosage of sodium chloride. When the dosage of humic acid sodium from 0 to 15g/L, the building-up performance of humic acid sodium was good. From the result of dynamics, the dyeing rate k was increased with the increase in dyeing temperature, half time of dyeing t1/2 and equilibrium dyeing uptake C∞ was decreased with the increase in dyeing temperature. From the result of thermodynamics, Freundlich equation can better fitted the absorption of humic acid sodium on cotton, humic acid sodium absorption on cotton main by hydrogen bonding and Van der waals forces.

Key words: sodium humate, cotton, &Delta, E value, absorption, kinetics, thermodynamics