羧甲基纤维素/蒙脱土纳米复合材料对刚果红染料的吸附及解吸性能

Adsorption and desorption properties for Congo red dye of carboxymethylcellulose/montmorillonite nanocomposites

用X射线衍射、透射电镜和扫描电镜对羧甲基纤维素/蒙脱土纳米复合材料的结构进行表征。采用溶液插层复合法制备纳米复合材料,探讨不同羧甲基纤维素与蒙脱土质量比、反应时间和反应温度对纳米复合材料吸附刚果红染料吸附量的影响,并初步研究了纳米复合材料的解吸性能。亚微观观察表明:羧甲基纤维素通过破坏蒙脱土的晶体结构插层进入蒙脱土层间,形成插层-剥离型纳米复合材料;当羧甲基纤维素与蒙脱土质量比为1∶1,反应时间为6h,反应温度为60℃时,纳米复合材料对刚果红染料的吸附量最大,可达50.42mg·g-1;当解吸试剂氢氧化钠浓度为0.01mol.L-1时,超声波解吸50min的纳米复合材料脱附率可达80.17%。

The structure of carboxymethylcellulose/montmorillonite（CMC/MMT）nanocomposites was characterized by X-ray diffraction（XRD）,transmission electron microscope（TEM）and scanning electron microscope（SEM）.The nanocomposites were prepared with a solution intercalation technique and the effects of mass ratio of carboxymethylcellulose to montmorillonite,reaction time and reaction temperature on adsorption capacity were investigated.The desorption properties were also investigated.Microscopic observation showed that carboxymethylcellulose intercalated into montmorillonite interlayer via destroying the crystalline structure of montmorillonite,and intercalated-exfoliated structure was formed in carboxymethylcellulose/montmorillonite nanocomposites.The maximum adsorption capacity of the nanocomposite for Congo red dye was as high as 50.42 mg·g-1 using the mass ratio of carboxymethylcellulose to montmorillonite of 1∶1 after being treated at 60℃ for 6 h.The desorption efficiency of the nanocomposite was 80.17% using desorption agent of 0.01 mol·L-1 NaOH after being treated by ultrasonic wave for 50 min.