Yi Ju-Zhen, Zhang Li-Ming
School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, PR China.
Bioresour Technol. 2008 May;99(7):2182-6. doi: 10.1016/j.biortech.2007.05.028. Epub 2007 Jun 29.
A type of novel hybrid hydrogels from sodium humate (SH), polyacrylamide (PAM), and hydrophilic laponite clay were prepared using potassium persulfate (KPS) as the initiator and N,N'-methylenebisacrylamide (MBA) as the cross-linker. The morphology of the hydrogels was characterized by field emission scanning electron microscope (FESEM). The adsorption-desorption kinetics of methylene blue (MB) were also investigated. It was shown that SH/PAM/clay hydrogels exhibited excellent performance in MB adsorption. The maximum absorption concentration of MB was 800 mg/l/g of hydrogel. The adsorption concentration of hydrogels increased with increasing SH or clay content. Less MB were desorbed with increasing SH content, while the clay content had no significant influence on the amount of MB desorbed. This effect was attributed to the formation of a ionic complex between the imine groups of MB and the ionized carboxylic groups of SH. MB diffusion process was dominant in MB desorption.
以过硫酸钾（KPS）为引发剂、N,N'-亚甲基双丙烯酰胺（MBA）为交联剂，制备了一种由腐殖酸钠（SH）、聚丙烯酰胺（PAM）和亲水性锂皂石粘土组成的新型杂化水凝胶。用场发射扫描电子显微镜（FESEM）对水凝胶的形态进行了表征。还研究了亚甲基蓝（MB）的吸附-解吸动力学。结果表明，SH/PAM/粘土水凝胶在MB吸附方面表现出优异的性能。MB的最大吸附浓度为800 mg/l/g水凝胶。水凝胶的吸附浓度随SH或粘土含量的增加而增加。随着SH含量的增加，解吸的MB减少，而粘土含量对MB的解吸量没有显著影响。这种效应归因于MB的亚胺基团与SH的离子化羧基之间形成了离子络合物。MB扩散过程在MB解吸中占主导地位。
