Hajeeth T, Sudha P N, Vijayalakshmi K, Gomathi T
Department of Chemistry, Sathyabama University, Chennai, Tamilnadu, India.
PG & Research Department of Chemistry, DKM College for Women, Vellore, Tamilnadu, India.
Int J Biol Macromol. 2014 May;66:295-301. doi: 10.1016/j.ijbiomac.2014.02.027. Epub 2014 Feb 20.
Graft copolymerization of acrylonitrile on to cellulosic material derived from sisal fiber can be initiated effectively with ceric ammonium nitrate. The grafting conditions were optimized by changing the concentration of initiator and monomer. The change in crystallinity of the grafted polymeric samples was concluded from the XRD patterns. The prepared cellulose grafted acrylonitrile copolymer was used as an adsorbent to remove Cr (VI) ions from aqueous solutions. The efficiency of the adsorbent was identified from the variation in the percentage of adsorption with contact time, adsorbent dose and pH. From the observed results it was evident that the adsorption of metal ions increases with the increase in contact time and metal ion concentration. An optimum pH was found to be 5.0 for the removal of Cr (VI) from the aqueous solution. The results of the Langmuir, Freundlich, and pseudo first- and second-order studies revealed that the adsorption was found to fit well with Freundlich isotherm and follows pseudo second-order kinetics. From the above results, it was concluded that the cellulose-g-acrylonitrile copolymer was found to be an efficient adsorbent for the removal of Cr (VI) from aqueous waste generated from industries.
硝酸铈铵可有效地引发丙烯腈在剑麻纤维衍生的纤维素材料上的接枝共聚反应。通过改变引发剂和单体的浓度对接枝条件进行了优化。从X射线衍射图谱得出接枝聚合物样品结晶度的变化。制备的纤维素接枝丙烯腈共聚物用作吸附剂，以从水溶液中去除Cr（VI）离子。根据吸附百分比随接触时间、吸附剂剂量和pH值的变化来确定吸附剂的效率。从观察结果可以明显看出，金属离子的吸附量随着接触时间和金属离子浓度的增加而增加。发现从水溶液中去除Cr（VI）的最佳pH值为5.0。朗缪尔、弗伦德利希以及准一级和二级研究的结果表明，吸附符合弗伦德利希等温线且遵循准二级动力学。从上述结果得出结论，纤维素接枝丙烯腈共聚物是从工业产生的废水去除Cr（VI）的有效吸附剂。
