U.S. flag

An official website of the United States government


Main content area

Fabrication of porous chitosan membranes composed of nanofibers by low temperature thermally induced phase separation, and their adsorption behavior for Cu2+

Qin, Wang, Li, Jixiang, Tu, Jianbing, Yang, Hongqin, Chen, Qinhui, Liu, Haiqing
Carbohydrate polymers 2017 v.178 pp. 338-346
acetic acid, adsorbents, adsorption, chitosan, coagulants, copper, ethanol, nanofibers, sodium carbonate, solvents, temperature
Low temperature thermally induced phase separation (LT-TIPS) of chitosan solution was developed to fabricate porous chitosan membranes (p-CSMs), which were composed of short nanofibers with diameter of 40–60nm. Compared to the conventional acetic acid/water solvent, a mixed solvent of acetic acid/ethanol/water was used to prepare chitosan solution. The effect of solvent composition, quenching temperature and time, and coagulant on the p-CSM morphology were systematically explored. The optimum conditions for fabricating p-CSM was to quench 2% chitosan/2% acetic acid in water/ethanol (70/30) at −20°C for 12h, followed by coagulating in 1% Na2CO3 in water/ethanol (50/50). The p-CSM was an effective adsorbent for Cu2+ and had a Langmuir adsorption capacity of 2.57mmol/g, which is close to the adsorption capacity of natural and electrospun chitosan nanofibers. The p-CSM maintained 90% adsorption efficiency for Cu2+ even after six cycles.