Flexible cellulose foams with a high loading of attapulgite nanorods for Cu2+ ions removal
Hong Ma, Xiong‐Fei Zhang, Zhongguo Wang, Lian Song, Jianfeng Yao
Abstract
This work proposed a facile and effective method to fabricate attapulgite (ATP)@cellulose composite foams. ATP nanorods were integrated into cellulosic matrix via mixing and freeze-drying process. The carboxylated nanocellulose served as skeleton for supporting and dispersing ATP. Moreover, the addition of CaCl2 could improve the mechanical stability of the composites and ultrahigh ATP loadings (> 80 wt%) could be achieved. In the adsorption test, a high metal ion removal efficiency was observed and the hybrid foams can be easily recycled and regenerated. The adsorption equilibrium data were well described by Langmuir isotherm model with a maximum adsorption capacity of 116.5 mg/g. There are three reasons to the good adsorption performance: 1) the hierarchal pore structure, 2) the good dispersion of ATP, and 3) the presence of abundant surface carboxyl groups. Such ATP@cellulose foams are biodegradable, facile to recover, flame-retardant and non-toxic, with great potential for water purification.