CA@CS-MMT复合纳米纤维的制备及对Cr(Ⅲ)的吸附  

Fabrication of cellulose acetate@chitosan-montmorillonite composite nanofibers and its adsorption of Cr(Ⅲ)

作　　者：张静 薛朝华 马宏瑞 高静 苏哲 ZHANG Jing;XUE Chaohua;MA Hongrui;GAO Jing;SU Zhe(School of Environmental Science and Engineering,Shaanxi University of Science&Technology,Xi'an 710021,Shaanxi,China;College of Bioresources Chemical and Materials Engineering,Shaanxi University of Science&Technology,Xi'an 710021,Shaanxi,China;National Demonstration Center for Experimental Light Chemistry Engineering Education,Shaanxi University of Science&Technology,Xi'an 710021,Shaanxi,China)

机构地区：[1]陕西科技大学环境科学与工程学院,陕西西安710021 [2]陕西科技大学轻工科学与工程学院,陕西西安710021 [3]陕西科技大学轻化工程国家级实验教学示范中心,陕西西安710021

出　　处：《精细化工》2021年第3期504-511,共8页Fine Chemicals

基　　金：国家自然科学基金(51372146,51572161);水污染控制重大专项(2017ZX07602-001)。

摘　　要：采用静电纺丝结合溶液插层法制备了醋酸纤维素@壳聚糖改性蒙脱土(CA@CS-MMT)复合纳米纤维,并用于水中Cr(Ⅲ)的吸附。通过SEM、TEM、FTIR及XRD对复合纳米纤维的结构与性能进行了表征,考察了CS-MMT含量、pH、温度、吸附剂用量及Cr(Ⅲ)初始质量浓度对吸附效果的影响。结果表明,CS-MMT的加入使纳米纤维的平均直径由320 nm下降至180~210 nm,当CS-MMT含量为CA质量的2%时,蒙脱土片层在纤维内部形成连续结构,制备的CA@CS-MMT-2对水中Cr(Ⅲ)具有良好的吸附性能,在25℃,pH为5.5±0.1,Cr(Ⅲ)初始质量浓度为50 mg/L,吸附剂用量为0.2 g/L时,拟合最大吸附量可达144.93 mg/g;吸附剂投加量为0.4~1.0 g/L时,可将水中Cr(Ⅲ)的质量浓度由10或20 mg/L降低至1.5 mg/L以下。该吸附过程符合Langmuir等温吸附和准二级动力学方程,循环3次后Cr(Ⅲ)吸附量仍可达99.13 mg/g。Cellulose acetate@chitosan modified montmorillonite composite nanofibers(CA@CS-MMT)were prpepared by electrospinning and solution intercalation.The structure and properties of the composite nanofibers were characterized by SEM,TEM,FTIR and XRD.And the adsorption properties of CA@CS-MMT nanofibers for Cr(Ⅲ)in water were studied.The results showed that the average diameter of nanofibers decreased from 320 nm to 180~210 nm with the increase of CS-MMT content.When the content of CS-MMT was 2%of the mass of cellulose acetate(CA),the lamellar structure of CS-MMT was assembled with CA to form the continuous structure in the CA@CS-MMT-2 composite nanofibers.The fitting maximum adsorption capacity of CA@CS-MMT-2 composite nanofiber was 144.93 mg/g under the conditions of pH=5.5±0.1,25℃,initial mass concentration of Cr(Ⅲ)of 50 mg/L and dosage of adsorpbent of 0.2 g/L.Importantly,when the dosage of adsorbent was 0.4~1.0 g/L,the Cr(Ⅲ)mass concentration could decrease from 20 or 10 mg/L to below 1.5 mg/L.The adsorption process was in accordance with Langmuir isothermal adsorption model and the adsorption kinetics conformed to pseudo-second-order kinetics equation.The adsorption capacity was still 99.13 mg/g after three cycles.

关 键 词：静电纺丝 溶液插层 蒙脱土 壳聚糖 醋酸纤维素 三价铬 功能材料 

分 类 号：X703[环境科学与工程—环境工程] TQ340.64[化学工程—化纤工业]