Study on dye adsorption of grafted cationic cocoon floss in printing and dyeing wastewater

Cationic grafting to cocoon floss with 2,3-epoxypropyl triethylammonium chloride( GTA) for modification,and the absorption effect of the modified cocoon floss to three reactive dyes,two acid dyes and a direct dye were studied. The infrared spectrum analysis shows that 2,3-epoxypropyl triethylammonium chloride is mainly grafted on amino of cocoon floss. The particle surface potential analysis shows that the value of the modified cocoon' s surface potential increases from- 56. 2 m V to- 23. 2 m V. The dye adsorption rate of the modified cocoon floss is very high,and majority of the adsorption is completed in the first 2- 4 min. The decolorization rates of the modified cocoon floss to the acid dyes and the direct dye are higher than the reactive dyes. The cationic grafting rate of the modified cocoon floss is higher,the dye adsorption capacity of the modified cocoon floss is greater. The modified cocoon floss with the grafting rate of 0. 31%- 2. 70% has the equilibrium adsorption values to the acid dyes,the direct dye and the reactive dyes are 16. 0%- 81. 3%, 31. 2%- 50. 6% and5. 16%- 32. 4%,respectively,showing that the modified cocoon floss has a very strong capacity to absorb dyes. And also,this is a potential method for the treatment of printing and dyeing wastewater.