Abstract: Dimethyl-butyl-sulfonated lignin ammonium chloride (DBSLAC) amphoteric surfactant was synthesized through Mannich and Sulfonating reaction using wheat straw alkali lignin as a raw material. Its structure was characterized by FT-IR, and the solubility in different pH solutions was evaluated. The effects of dimethyl-butyl-sulfonated lignin ammonium chloride on the adsorption performance was investigated with copper ions as simulate wastewater, while its flocculation performance was investigated with acid black ATT and methylene blue wastewater as the simulation dyes. The results showed that sulfonic group and quaternary amine group were successfully grafed, and nitrogen content of DBSLAC was 2.34%. DBSLAC amphoteric surfactant on the adsorption isotherms of copper ions could be fitted well by Freundlich equation, when the optimum adsorption conditions for Cu²⁺ were the dosage of 0.002 g(the initial mass concentration of Cu²⁺ 100 mg/L, solution volume 20 mL), pH 5.5 and adsorption time of 2 h. Under this condition, the maximum adsorption capacity was 262.34 mg/g. The maximum removal rate of 20 mL Acid black ATT (anionic dye) was 75.41% when the optimum flocculation conditions were the dosage of 0.03 g, pH 2 and mass concentration of dye of 0.1 g/L. The maximum removal rate of 20 mL methylene blue (cationic dye) was 97.87%, when the optimum flocculation conditions were the dosage of 0.3 g, pH 9 and mass concentration of dye of 0.1 g/L. The result shows that DBSLAC amphoteric surfactant will be expected to a novel adsorbent for heavy metal ion and flocculants of dyes.

Key words: alkali lignin, dimethyl-butyl-sulfonated lignin ammonium chloride, amphoteric surfactants, adsorbents, flocculants