Nuclear Materials Authority, P.O. Box 530, El-Maadi, Cairo, Egypt.
Hosei University, Faculty of Bioscience and Applied Chemistry, Japan.
Carbohydr Polym. 2017 Feb 10;157:1809-1820. doi: 10.1016/j.carbpol.2016.11.064. Epub 2016 Nov 23.
The grafting of amino and carboxylic acid groups on cellulose increased La(III) sorption efficiency of cellulose: maximum sorption capacity increased from 38mgLag for cellulose to 101 and 170mgLag for amino derivative (PAC) and amino-carboxylic derivative (PCMC). Langmuir equation successfully fits sorption isotherms while uptake kinetics are effectively modeled using the pseudo-first order rate equation (though resistance to intraparticle diffusion plays a significant role in the control of metal recovery). Uptake equilibrium occurred within 150-180min. The thermodynamic study shows that the reaction is spontaneous, endothermic and entropic. Nitric acid solutions (0.5M concentration) can be efficiently used for metal recovery and sorbent can be recycled for at least 5 cycles with limited decrease in sorption performance for the three sorbents. The materials were characterized by elemental analysis, acid-base titration, FTIR spectrometry, x-ray diffraction analysis, X-ray photoelectron spectroscopy, SEM-EDX analysis and also by TGA.
将氨基和羧基基团接枝到纤维素上提高了纤维素对镧（III）的吸附效率：吸附容量从纤维素的 38mgLag 增加到氨基衍生物（PAC）和氨基-羧基衍生物（PCMC）的 101 和 170mgLag。Langmuir 方程成功拟合了吸附等温线，而采用拟一级速率方程有效地模拟了吸附动力学（尽管颗粒内扩散阻力在控制金属回收方面起着重要作用）。在 150-180min 内达到吸附平衡。热力学研究表明，该反应是自发的、吸热的和熵增的。硝酸溶液（0.5M 浓度）可有效用于金属回收，并且三种吸附剂的吸附性能在至少 5 次循环中都有一定程度的下降，可重复使用。采用元素分析、酸碱滴定、傅里叶变换红外光谱、X 射线衍射分析、X 射线光电子能谱、SEM-EDX 分析和 TGA 对材料进行了表征。
