甲基丙烯酸接枝纳米纤维素水凝胶的制备及吸附性能研究

Preparation and adsorption properties of methacrylic acid grafted nano cellulose hydrogel

本文通过酸解法制备纳米纤维素(nCE),再利用自由基聚合法将甲基丙烯酸(MAA)接枝到纳米纤维素上,得到含有多孔结构的纤维素基水凝胶,并以制备的水凝胶作为吸附剂处理染料废水。用傅里叶变换红外光谱仪(FTIR)、和扫描电镜(SEM)技术对其进行了表征。讨论了吸附时间、pH、染料初始浓度、吸附剂用量对染料去除率的影响,优化了吸附条件。并对吸附机理进行了探讨,吸附动力学符合准二级动力学模型,平衡吸附等温线与Langmuir吸附等温方程拟合。通过对吸附等温线的拟合,计算得到了吸附剂对亚甲基蓝(MB)的最大吸附量为1250.00 mg·g^(-1)。

The nano cellulose(nCE)was prepared by acid hydrolysis method,methacrylic acid(MAA)grafted nano cellulose hydrogel was prepared by using the free radical polymerization.Cellulose-based hydrogels with porous structure was applied to treat dye wastewater.The products were characterized by Fourier transform infrared spectroscopy(FTIR)and scanning electron microscopy(SEM).The influences of adsorption time,pH,initial dye concentration and adsorbent dosage on the dye removal efficiency were discussed.The adsorption mechanism was also discussed,and the pseudo-second-order model fitted MB adsorption better than the pseudo-first-order.The equilibrium adsorption isotherm was fitted to the Langmuir adsorption.The Langmuir isotherm model revealed that the maximum theoretical adsorption capacity of this hydrogel was 1250 mg·g^-1.