【摘要】 以棉浆纤维素（CF）为原料,利用漆酶/TEMPO体系选择性将其C6伯羟基氧化成醛基,得到氧化纤维素（OCF）,再将天冬氨酸通过Schiff碱反应接枝到氧化纤维素上,制得一种新型的重金属离子吸附材料。采用傅里叶红外光谱（FT-IR）和扫描电子显微镜（SEM）等表征手段证实了天冬氨酸成功引入到纤维素的表面,且利用凯氏定氮法检测得到接枝产物中天冬氨酸含量为5.28%。以重金属镍离子(Ni²⁺)为模型物,研究了天冬氨酸-纤维素吸附剂（Asp-OCF）对镍离子溶液的吸附性能,探讨了镍离子初始浓度和吸附时间对吸附过程的影响。结果表明,与纤维素相比,制备的新型吸附剂Asp-OCF对Ni²⁺的吸附能力大幅提高,平衡吸附量达到9.48 mg/g,相比CF提高了8倍。吸附等温线拟合结果较好的符合Langmuir模型;动力学研究结果表明Asp-OCF对Ni²⁺的吸附过程符合准二级动力学模型。更多还原

【Abstract】 A novel heavy metal ion adsorbing material was prepared by grafting Aspartic acid onto oxidized cotton fiber（OCF） which could be obtained by oxidizing C-6-hydroxyl groups of cotton fiber（CF） into aldehyde groups with laccase/TEMPO system. The properties of obtained product were characterized by Fourier Transform Infrared（FTIR） and Scanning Electron Microscope（SEM）. The results indicated that Aspartic acid was successfully introduced into the surface of cellulose. Besides, the content of aspartic acid in product was 5.28%, resulting from kjeldahl method. The adsorption performance of Aspartic acid-cellulose adsorbent（Asp-OCF） for nickel ion were studied by using heavy metal nickel ion(Ni²⁺) as a model. The effects of initial concentration of nickel ion and adsorption time on the adsorption process were discussed. Compared with cellulose, the adsorption capacity of the Asp-OCF for Ni²⁺ was significantly improved, and the equilibrium adsorption amount could reach 9.48 mg/g, which was 8 times higher than that of CF. The results of adsorption isotherm indicated that the adsorption process of Asp-OCF was in good agreement with Langmuir model. Meanwhile, the kinetic results showed that the adsorption process of Ni²⁺ by Asp-OCF conformed to the quasi-second order kinetic model.更多还原