单宁的疏水修饰及对亚甲基蓝的吸附特性

Hydrophobic Modification of Tannin and Its Adsorption Properties for Methylene Blue

将乙胺通过Michael加成反应引入单宁分子结构中对单宁进行疏水修饰,单宁经疏水修饰后表面变得粗糙,其水溶性降低,对紫外光的吸收波长范围变宽。疏水单宁能较好的吸附亚甲基蓝,疏水单宁对180 mg/L亚甲基蓝的吸附量达158.13 mg/g;疏水单宁用量为0.8 g/L时,其对20 mg/L亚甲基蓝可达97.67%的吸附率。疏水单宁对亚甲基蓝的吸附遵循Langmuir等温模型和准二级动力学模型。

Hydrophobic tannin was prepared by the Michael addition reaction of ethylamine and tannin.The surface of hydrophobic tannin became rough,its water solubility decreased,and the absorption wavelength range for ultraviolet light became wider.The adsorption capacity of hydrophobic tannin for 180 mg/L methylene blue was 158.13 mg/g;when the amount of hydrophobic tannin was 0.8 g/L,the adsorption rate of hydrophobic tannin for 20 mg/L methylene blue reached 97.67%.The adsorption of methylene blue on hydrophobic tannin conforms to Langmuir isotherm model and quasi second order kinetic model.